Richard Lyon

Professor Richard Lyon MBE


Professor in Pre-Hospital Emergency Medicine

Academic and research departments

School of Health Sciences.

About

Publications

Richard M Lyon (2011)Time for a national register, In: BMJ342(7792)d478pp. 298-298
R.M. Lyon, S. Clarke, D. Milligan, G.R. Clegg (2012)Resuscitation feedback and targeted education improves quality of pre-hospital resuscitation in Scotland, In: Resuscitation83(1)pp. 70-75 Elsevier Ireland Ltd

Out-of-hospital cardiac arrest (OHCA) is a leading cause of mortality and serious neurological morbidity in Europe. Recent studies have demonstrated the adverse physiological consequences of poor resuscitation technique and have shown that quality of cardiopulmonary resuscitation (CPR) is a critical determinant of outcome from OHCA. Telemetry of the defibrillator transthoracic impedance (TTI) trace can objectively measure quality of pre-hospital resuscitation. This study aims to analyse the impact of targeted resuscitation feedback and training on quality of pre-hospital resuscitation. Prospective, single centre, cohort study over 13 months (1st December 2009–31st December 2010). Baseline pre-hospital resuscitation data was gathered over a 3-month period. Modems (n=40) were fitted to defibrillators on ambulance vehicles. Following a resuscitation attempt, the event was sent via telemetry and the TTI trace analysed. Outcome measures were time spent performing chest compressions, compression rate, the interval required to deliver a defibrillator shock and use of automatic or manual cardiac rhythm analysis. Targeted resuscitation classes were introduced and all ambulance crews received feedback following a resuscitation attempt. Pre-hospital resuscitation quality pre and post intervention were compared. 111 resuscitation traces were analysed. Mean hands-on-chest time improved significantly following feedback and targeted resuscitation training (73.0% vs 79.3%, p=0.007). There was no significant change in compression rate during the study period. There was a significant reduction in median time-to-shock interval from 20.25s (IQR 15.50–25.50s) to 13.45s (IQR 2.25–22.00s) (p=0.006). Automatic rhythm recognition fell from 50% to 28.6% (p=0.03) following intervention. Telemetry and analysis of the TTI trace following OHCA allows objective evaluation of the quality of pre-hospital resuscitation. Targeted resuscitation training and ambulance feedback improves the quality of pre-hospital resuscitation. Further studies are required to establish possible survival benefit from this technique.

Richard M. Lyon, John Shepherd, Gareth R. Clegg (2011)Early in-hospital management of out-of-hospital cardiac arrest in Scotland: a national survey, In: European journal of emergency medicine18(2)pp. 102-104 Lippincott Williams & Wilkins

Guidelines recommend the use of mild therapeutic hypothermia (MTH) and percutaneous coronary intervention (PCI) in the early post-resuscitation management of select out-of-hospital cardiac arrest (OHCA) cases. This study aims to assess the current use of MTH and PCI in Scottish Emergency Departments (ED) and Intensive Care Units (ICU). We conducted a questionnaire survey of all the Scottish Emergency Medicine Consultants, EDs and ICUs. MTH was more commonly initiated in ICU than in the ED (19; 91 vs. 7; 37%, P

R Lyon, M Hawkins, M Mackinnon, S J McNally (2008)Surviving sepsis in Scotland: is the emergency department ready?, In: Critical care (London, England)12(Suppl 2)pp. P416-P416 BioMed Central
Richard Lyon (2011)Therapeutic hypothermia post out-of-hospital cardiac arrest - more questions than answers?, In: Critical care (London, England)15(2)151pp. 151-151

Nearly a decade since the introduction of therapeutic hypothermia to the ICU for cooling out-of-hospital cardiac arrest patients, key questions remain unanswered: when should cooling be initiated, how rapidly should the patient be cooled and using which device? The Time to Target Temperature study group provides important baseline data on the striking direct relationship between body temperature and survival from out-of-hospital cardiac arrest.

R. M. Lyon, G. R. Clegg (2011)Pre-hospital cooling for out-of-hospital cardiac arrest-More research required, In: Resuscitation82(8)1108pp. 1108-1109 Elsevier
R.M. Lyon, S.E. Richardson, A.W. Hay, P.J.D. Andrews, C.E. Robertson, G.R. Clegg (2010)Esophageal temperature after out-of-hospital cardiac arrest: An observational study, In: Resuscitation81(7)867pp. 867-871 Elsevier Ireland Ltd

Out-of-hospital cardiac arrest (OHCA) is a significant cause of death and severe neurological disability. The only post-return of spontaneous circulation (ROSC) therapy shown to increase survival is mild therapeutic hypothermia (MTH). The relationship between esophageal temperature post OHCA and outcome is still poorly defined. Prospective observational study of all OHCA patients admitted to a single centre for a 14-month period (1/08/2008 to 31/09/2009). Esophageal temperature was measured in the Emergency Department and Intensive Care Unit (ICU). Selected patients had pre-hospital temperature monitoring. Time taken to reach target temperature after ROSC was recorded, together with time to admission to the Emergency Department and ICU. 164 OHCA patients were included in the study. 105 (64.0%) were pronounced dead in the Emergency Department. 59 (36.0%) were admitted to ICU for cooling; 40 (24.4%) died in ICU and 19 (11.6%) survived to hospital discharge. Patients who achieved ROSC and had esophageal temperature measured pre-hospital ( n = 29) had a mean pre-hospital temperature of 33.9 °C (95% CI 33.2–34.5). All patients arriving in the ED post OHCA had a relatively low esophageal temperature (34.3 °C, 95% CI 34.1–34.6). Patients surviving to hospital discharge were warmer on admission to ICU than patients who died in hospital (35.7 °C vs 34.3 °C, p< 0.05). Patients surviving to hospital discharge also took longer to reach T targ than non-survivors (2 h 48 min vs 1 h 32 min, p< 0.05). Following OHCA all patients have esophageal temperatures below normal in the pre-hospital phase and on arrival in the Emergency Department. Patients who achieve ROSC following OHCA and survive to hospital discharge are warmer on arrival in ICU and take longer to reach target MTH temperatures compared to patients who die in hospital. The mechanisms of action underlying esophageal temperature and survival from OHCA remain unclear and further research is warranted to clarify this relationship.

Richard M. Lyon, Jerry Van Antwerp, Charles Henderson, Anne Weaver, Gareth Davies, David Lockey (2014)Prehospital intranasal evaporative cooling for out-of-hospital cardiac arrest: a pilot, feasibility study, In: European journal of emergency medicine21(5)pp. 368-370 Lippincott Williams & Wilkins

Intranasal evaporative cooling presents a novel means of initiating therapeutic hypothermia after an out-of-hospital cardiac arrest (OHCA). Few studies have evaluated the use of intranasal therapeutic hypothermia using the Rhinochill device in the prehospital setting. We sought to evaluate the use of Rhinochill in the Physician Response Unit of London's Air Ambulance, aiming to describe the feasibility of employing it during prehospital resuscitation for OHCA. We prospectively evaluated the Rhinochill device over a 7-month period. Inclusion criteria for deployment included: age above 18 years, Physician Response Unit on-scene within maximum of 10 min after return-of-spontaneous circulation (ROSC), witnessed OHCA or unwitnessed downtime of less than 10 min, pregnancy not suspected, normal nasal anatomy, and likely ICU candidate if ROSC were to be achieved. Thirteen patients were included in the evaluation. The average time from the 999 call to initiation of cooling was 39.5 min (range 22-61 min). The average prehospital temperature change in patients who achieved ROSC was -1.9 degrees C. Patients were cooled for an average of 38 min prehospital. In all cases, the doctor and paramedic involved with the resuscitation reported that the Rhinochill was easy to set up and use during resuscitation and that it did not interfere with standard resuscitation practice. Intranasal evaporative cooling using the Rhinochill system is feasible in an urban, prehospital, doctor/paramedic response unit. Cooling with Rhinochill was not found to interfere with prehospital resuscitation and resulted in significant core body temperature reduction. Further research on the potential benefit of intra-arrest and early initiation of intranasal evaporative cooling is warranted. (C) 2014 Wolters Kluwer Health vertical bar Lippincott Williams & Wilkins.

Georg M. Froehlich, Richard M. Lyon, Comilla Sasson, Tom Crake, Mark Whitbread, Andreas Indermuehle, Adam Timmis, Pascal Meier (2013)Out-of-Hospital Cardiac Arrest - Optimal Management, In: Current cardiology reviews9(4)316pp. 316-324 Bentham Science Publ Ltd

Out-of-hospital cardiac arrest (OHCA) has attracted increasing attention over the past years because outcomes have improved impressively lately. The changes for neurological intact outcomes has been poor but several areas have achieved improving survival rates after adjusting their cardiac arrest care. The pre-hospital management is certainly key and decides whether a cardiac arrest patient can be brought back into a spontaneous circulation. However, the whole chain of resuscitation including the in-hospital care have improved also. This review describes aetiologies of OHCA, risk and potential protective factors and recent advances in the pre-hospital and in-hospital management of these patients.

Richard M Lyon, John D Ferris, Danielle M Young, Dermot W McKeown, Angela J Oglesby, Colin Robertson (2010)Field intubation of cardiac arrest patients: a dying art?, In: Emergency medicine journal : EMJ27(4)321pp. 321-323 BMJ Publishing Group Ltd and the British Association for Accident & Emergency Medicine

Introduction The most appropriate advanced airway intervention in out-of-hospital cardiac arrest (OHCA) is unproven. This study reviews prehospital advanced airway management and its complications in OHCA patients. Methods A 4-year, observational, retrospective case review. Patients attending the Emergency Department of the Royal Infirmary of Edinburgh, Scotland, with a primary diagnosis of OHCA were identified. Patient demographics, survival to admission, airway management technique and complication rates were identified. Results Seven hundred and ninety-four cases were identified. The aetiology of cardiac arrest was medical in 95.2%, traumatic in 3.9% and unrecorded in 0.9%. Prehospital intubation was attempted in 628 patients. Prehospital intubation was successful in 573 patients. A significant complication (multiple attempts, displaced endotracheal tube or oesophageal intubation) occurred in 55 (8.8%) patients. 165 (20.8%) patients survived to hospital admission, of whom 110 had undergone prehospital intubation. 55 patients who did not undergo prehospital tracheal intubation survived to hospital admission. Conclusion The optimal method of maintaining an airway and ventilating an OHCA patient has yet to be established. Prehospital tracheal intubation for OHCA is associated with significant complications and may reduce survival. The use of tracheal intubation as a routine intervention should be reconsidered. Ambulance services should consider adopting alternative strategies in airway management.

Richard M Lyon, Stephen J McNally, Martin Hawkins, Marian MacKinnon (2010)Early goal-directed therapy: can the emergency department deliver?, In: Emergency medicine journal : EMJ27(5)355pp. 355-358

BackgroundEarly goal-directed therapy (EGDT) has been shown to improve outcome in patients presenting to the emergency department (ED). Uptake of EGDT in EDs in the UK has been slow.ObjectiveTo establish the level of awareness and skills necessary for EGDT to be implemented by emergency medicine (EM) specialist registrars (SpR) working in Scottish EDs.MethodA cross-sectional web-based survey of all 49 Scottish EM SpRs was performed.Results42 responses were obtained (86%). Only 19 (45%) EM SpRs possessed the full complement of skills and knowledge necessary to fully implement EGDT independently within the ED. The 4 h target for time to admission was seen by 78% of SpRs as a barrier to the implementation of EGDT in the ED. The preference of most respondents was for initiation of EGDT delivery in the ED and referral to critical care for full implementation.ConclusionFull delivery of EGDT by ED staff would require significant consultant support, improved training of juniors and flexibility in the 4 h target. This study suggests that it may be practical for EGDT to be initiated in the ED and that early referral to critical care will remain essential if patients are to receive the full benefit of this intervention.

R. Ghose, R. M. Lyon, G. R. Clegg, A. J. Gray (2010)Bystander CPR in south east Scotland increases over 16 years, In: Resuscitation81(11)1488pp. 1488-1491 Elsevier

Background: Out-of-hospital cardiac arrest (OHCA) remains a leading cause of mortality and serious neurological disability across Europe. Without immediate bystander cardiopulmonary resuscitation (CPR), chances of survival are minimal. Despite community initiatives to increase the number of trained CPR providers, the effectiveness of these measures remains unknown and the proportion of OHCA patients receiving bystander CPR in the United Kingdom yet to be established. We sought to identify the change in the rate of bystander CPR in south east Scotland over a 16-year period. Methods: Retrospective cohort study of all adult non-traumatic OHCA in south east Scotland from 1 January 1992 to 31 December 2007 using the Heartstart Scotland database. Results: 7928 OHCA were included. The proportion of patients receiving bystander CPR increased from 34% in 1992 to 52% in 2007 (p for trend

Richard M. Lyon, Neil Sinclair (2012)National standards in prehospital resuscitation training are required, In: Emergency medicine journal : EMJ29(7)pp. 602-602 BMJ Publishing Group
R.M. Lyon, C.M. Wiggins (2010)Expedition Medicine—the Risk of Illness and Injury, In: Wilderness & environmental medicine21(4)318pp. 318-324 SAGE Publications

Objective Expeditions organized by commercial companies are becoming increasingly popular. Charity expeditions take inexperienced participants on trips all over the world, with participants being sponsored to raise funds for charitable causes. The incidence of illness or injury while participating in charity expeditions is unknown. The objective of this study is to report the incidence and severity of illness and injuries occurring on worldwide charity expeditions. Methods Retrospective, observational study reviewing expedition medical reports from 232 expeditions organized by a single commercial expedition company for a 5-year period (January 1, 2004 through December 31, 2008). Results Complete expedition medical reports were available for 210 (91%) trips, involving 4077 participants over 1524 expedition days. Expeditions reported a total of 1564 incidents over 42 482 participant-days in the field, including days spent traveling to the expedition site. In 1465 (94%) cases “minor” injury or illness was recorded, 79 (5%) “moderate,” and 20 (1%) “major” in severity. No deaths were reported. Gastrointestinal upset was the commonest reported minor condition and severe acute mountain sickness the commonest major condition. Overall, the incidence per 1000 participant-days of minor illness or injury was 34.48, moderate illness or injury 1.86, and major illness or injury 0.47. Conclusion The risk of sustaining major injury or illness on an overseas charity expedition is low. The consequences of becoming injured or unwell in a remote environment can be serious, and appropriate medical care is required.

Jerry P. Nolan, Richard M. Lyon, Comilla Sasson, Andrea O. Rossetti, Alexandra J. Lansky, Keith A. A. Fox, Pascal Meier (2012)Advances in the hospital management of patients following an out of hospital cardiac arrest, In: Heart (British Cardiac Society)98(16)1201pp. 1201-1206 Bmj Publishing Group

The outcome for patients after an out-of-hospital cardiac arrest (OHCA) has been poor over many decades and single interventions have mostly resulted in disappointing results. More recently, some regions have observed better outcomes after redesigning their cardiac arrest pathways. Optimised resuscitation and prehospital care is absolutely key, but in-hospital care appears to be at least as important. OHCA treatment requires a multidisciplinary approach, comparable to trauma care; the development of cardiac arrest pathways and cardiac arrest centres may dramatically improve patient care and outcomes. Besides emergency medicine physicians, intensivists and neurologists, cardiologists are playing an increasingly crucial role in the post-resuscitation management, especially by optimising cardiac output and undertaking urgent coronary angiography/intervention.

Richard M Lyon, Joe Vernon, Magnus Nelson, Neal Durge, Malcolm Tunnicliff, Leigh Curtis, Malcolm Q Russell (2015)The Need for a UK Helicopter Emergency Medical Service by Night: A Prospective, Simulation Study, In: Air medical journal34(4)195pp. 195-198

Major trauma commonly occurs at night. Helicopter emergency medical services (HEMS) can provide advanced prehospital care to victims of major trauma but do not routinely operate at night in the United Kingdom. We sought to prospectively examine the need for a night HEMS service in Kent, Surrey, and Sussex in the United Kingdom. A 4-month, prospective study was conducted (July 1, 2012-October 31, 2012). HEMS dispatch paramedics were present in the ambulance dispatch center and undertook simulated HEMS activations when a suitable case was identified. All trauma cases from the 4-month study period were collated. Five independent HEMS clinicians reviewed the simulated tasking and trauma cases and gave an opinion on whether the patient met HEMS activation criteria. A mission rate of 1 case per night was predefined as cost-effective. During the prospective study, 145 calls were identified by the HEMS dispatch paramedic as appropriate for an HEMS response. If HEMS had deployed to all 145 incidents, this would have resulted in an average mission rate of 1.2 activations per night. Two hundred eight incidents were identified as potentially appropriate for HEMS activation. Responding to all 208 incidents would have resulted in a mean activation rate of 1.7 per night. This study justifies the need for Kent, Surrey and Sussex Air Ambulance Trust to operate a service at night for a trial period, with an estimated average mission load of 1 per night spread over the entire night period. Further research is warranted to determine the potential impact of a night HEMS service on outcome from major trauma.

Background: Survival from out-of-hospital cardiac arrest (OHCA) is dependent on the chain of survival. Early recognition of cardiac arrest and provision of bystander cardiopulmonary resuscitation (CPR) are key determinants of OHCA survival. Emergency medical dispatchers play a key role in cardiac arrest recognition and giving telephone CPR advice. The interaction between caller and dispatcher can influence the time to bystander CPR and quality of resuscitation. We sought to pilot the use of emergency call transcription to audit and evaluate the holdups in performing dispatch-assisted CPR. Methods: A retrospective case selection of 50 consecutive suspected OHCA was performed. Audio recordings of calls were downloaded from the emergency medical dispatch centre computer database. All calls were transcribed using proprietary software and voice dialogue was compared with the corresponding stage on the Medical Priority Dispatch System (MPDS). Time to progress through each stage and number of caller-dispatcher interactions were calculated. Results: Of the 50 downloaded calls, 47 were confirmed cases of OHCA. Call transcription was successfully completed for all OHCA calls. Bystander CPR was performed in 39 (83%) of these. In the remaining cases, the caller decided the patient was beyond help (n = 7) or the caller said that they were physically unable to perform CPR (n=1). MPDS stages varied substantially in time to completion. Stage 9 (determining if the patient is breathing through airway instructions) took the longest time to complete (median = 59s, IQR 22-82 s). Stage 11 (giving CPR instructions) also took a relatively longer time to complete compared to the other stages (median = 46s, IQR 37-75 s). Stage 5 (establishing the patient's age) took the shortest time to complete (median = 5.5s, IQR 3-9 s). Conclusion: Transcription of OHCA emergency calls and caller-dispatcher interaction compared to MPDS stage is feasible. Confirming whether a patient is breathing and completing CPR instructions required the longest time and most interactions between caller and dispatcher. Use of call transcription has the potential to identify key factors in caller-dispatcher interaction that could improve time to CPR and further research is warranted in this area. (C) 2013 Elsevier Ireland Ltd. All rights reserved.

Richard M. Lyon, Ben Macauley, Sarah Richardson, Richard de Coverly, Malcolm Russell (2015)Helicopter emergency medical services response to equestrian accidents, In: European journal of emergency medicine22(2)pp. 103-106 Lippincott Williams & Wilkins

Background Horse riding is a common leisure activity associated with a significant rate of injury. Helicopter emergency medical services (HEMS) may be called to equestrian accidents. Accurate HEMS tasking is important to ensure appropriate use of this valuable medical resource. We sought to review HEMS response to equestrian accidents and identify factors associated with the need for HEMS intervention or transport of the patient to a major trauma centre. Methods Retrospective case review of all missions flown by Kent, Surrey & Sussex Air Ambulance Trust over a 1-year period (1 July 2011 to 1 July 2012). All missions were screened for accidents involving a horse. Call details, patient demographics, suspected injuries, clinical interventions and patient disposition were all analysed. Results In the 12-month data collection period there were 47 equestrian accidents, representing similar to 3% of the total annual missions. Of the 42 cases HEMS attended, one patient was pronounced life extinct at the scene. In 15 (36%) cases the patient was airlifted to hospital. In four (10%) cases, the patient underwent prehospital anaesthesia. There were no specific predictors of HEMS intervention. Admission to a major trauma centre was associated with the rider not wearing a helmet, a fall onto their head or the horse falling onto the rider. Conclusion Equestrian accidents represent a significant proportion of HEMS missions. The majority of patients injured in equestrian accidents do not require HEMS intervention, however, a small proportion have life-threatening injuries, requiring immediate critical intervention. Further research is warranted, particularly regarding HEMS dispatch, to further improve accuracy of tasking to equestrian accidents. Copyright (C) 2015 Wolters Kluwer Health, Inc. All rights reserved.

Teresa Cullip, Anthony Hudson, Richard Lyon, Emily McWhirter (2014)Testing alertness of Helicopter Emergency Medical Service (HEMS) crews – a feasibility study, In: Scandinavian journal of trauma, resuscitation and emergency medicine22(Suppl 1)O1pp. O1-O1 BioMed Central
D Young, R M Lyon, J Ferris, D W McKeown, A Oglesby (2009)Prehospital intubation for out-of-hospital cardiac arrest, In: Critical care (London, England)13(Suppl 1)pp. P60-P60 BioMed Central
Richard M. Lyon (2012)Extra-corporeal cardiopulmonary resuscitation – Miracle cure or expensive futility?, In: Resuscitation83(11)1311pp. 1311-1312 Elsevier Ireland Ltd
Scott Clarke, Richard M Lyon, Steven Short, Colin Crookston, Gareth R Clegg (2014)A specialist, second-tier response to out-of-hospital cardiac arrest: setting up TOPCAT2, In: Emergency medicine journal : EMJ31(5)405pp. 405-407

Background Out-of-hospital cardiac arrest (OHCA) is the most common, immediately life-threatening, medical emergency faced by ambulance crews. Survival from OHCA is largely dependent on quality of prehospital resuscitation. Non-technical skills, including resuscitation team leadership, communication and clinical decision-making are important in providing high quality prehospital resuscitation. We describe a pilot study (TOPCAT2, TC2) to establish a second tier, expert paramedic response to OHCA in Edinburgh, Scotland. Methods Eight paramedics were selected to undergo advanced training in resuscitation and non-technical skills. Simulation and video feedback was used during training. The designated TC2 paramedic manned a regular ambulance service response car and attended emergency calls in the usual manner. Emergency medical dispatch centre dispatchers were instructed to call the TC2 paramedic directly on receipt of a possible OHCA call. Call and dispatch timings, quality of cardiopulmonary resuscitation and return-of-spontaneous circulation were all measured prospectively. Results Establishing a specialist, second-tier paramedic response was feasible. There was no overall impact on ambulance response times. From the first 40 activations, the TC2 paramedic was activated in a median of 3.2 min (IQR 1.6–5.8) and on-scene in a median of 10.8 min (8.0–17.9). Bimonthly team debrief, case review and training sessions were successfully established. OHCA attended by TC2 showed an additional trend towards improved outcome with a rate of return of spontaneous circulation of 22.5%, compared with a national average of 16%. Conclusions Establishing a specialist, second-tier response to OHCA is feasible, without impacting on overall ambulance response times. Improving non-technical skills, including prehospital resuscitation team leadership, has the potential to save lives and further research on the impact of the TOPCAT2 pilot programme is warranted.

Richard M. Lyon, Gerry Egan, Paul Gowens, Peter Andrews, Gareth Clegg (2010)Issues around conducting prehospital research on out-of-hospital cardiac arrest: lessons from the TOPCAT study, In: Emergency medicine journal : EMJ27(8)pp. 637-638 BMJ Publishing Group

Outcome from OHCA is primarily determined by prehospital events and meaningful clinical OHCA research must include data recorded in this setting. There is little evidence on which to base the practice of prehospital resuscitation and research in this area presents huge challenges but is required if survival from OHCA is to improve. This short report aims to provide a practical guide to performing prehospital research on OHCA, based on lessons learned from the Temperature Post Cardiac Arrest (TOPCAT) research; an observational study into OHCA.

Richard M. Lyon (2014)Pre-hospital resuscitation exposure - When is enough, enough?, In: Resuscitation85(9)pp. 1121-1122 Elsevier
Richard M. Lyon, Jon Sanders (2012)The Swiss bus accident on 13 March 2012: lessons for pre-hospital care, In: Critical care (London, England)16(4)138pp. 138-138 Springer Nature

The recent bus crash in Switzerland involving many children provides several lessons for the pre-hospital care community. The use of multiple helicopters that are capable of flying at night and that carry advanced medical pre-hospital teams undoubtedly saved lives following the tragedy. We describe the medical response to the incident and the lessons that can be learned for emergency medical services.

Richard M. Lyon, Julian Thompson, David J. Lockey (2013)Tissue oxygen saturation measurement in prehospital trauma patients: a pilot, feasibility study, In: Emergency medicine journal : EMJ30(6)506pp. 506-508 Bmj Publishing Group

Background This study evaluated the feasibility of prehospital tissue oxygen saturation (StO(2)) in major trauma patients. Methods A prospective, pilot feasibility study carried out in a physician based prehospital trauma service. Results Prehospital StO(2) was recorded on 13 patients. Continuous StO(2) monitoring was achieved on all patients, despite intermittent failure of pulse oximetry and non-invasive blood pressure monitoring in six patients. No adverse outcomes of StO(2) monitoring were reported. The specific equipment used was reported to be inconveniently bulky and heavy for use in the prehospital setting. Conclusions Prehospital measurement and monitoring of StO(2) is feasible in trauma patients undergoing prehospital anaesthesia and may be useful in the early identification of shock, triggering of transfusion protocols and guiding fluid resuscitation.

Alan Cowley, David Wright, Thomas Breen, Richard Lyon (2016)Todd's Paresis in Acute Mild Head Trauma, In: Air medical journal35(6)pp. 369-370

We present the case of an adult male who sustained Todd's paresis after a traumatically induced seizure in a patient with an isolated facial injury. The precipitating event was head trauma from a golf club. The patient had no previous history of seizures and went on to make a complete neurologic recovery with no cerebral pathology noted. A literature review suggests that Todd's paresis after trauma is very rare as opposed to occurring in the medical or long-term brain injury settings. Although the authors acknowledge that it may occur in trauma, the awareness within the prehospital setting is sufficiently rare for this case report to be of interest to prehospital clinicians; it is important prehospital clinicians are aware of this condition.

Richard M. Lyon, Magnus J. Nelson (2013)Helicopter emergency medical services (HEMS) response to out-of-hospital cardiac arrest, In: Scandinavian journal of trauma, resuscitation and emergency medicine21(1)1pp. 1-1 Springer Nature

Background: Out-of-hospital cardiac arrest (OHCA) is a common medical emergency with significant mortality and significant neurological morbidity. Helicopter emergency medical services (HEMS) may be tasked to OHCA. We sought to assess the impact of tasking a HEMS service to OHCA and characterise the nature of these calls. Method: Retrospective case review of all HEMS calls to Surrey and Sussex Air Ambulance, United Kingdom, over a 1-year period (1/9/2010-1/9/2011). All missions to cases of suspected OHCA, of presumed medical origin, were reviewed systematically. Results: HEMS was activated 89 times to suspected OHCA. This represented 11% of the total HEMS missions. In 23 cases HEMS was stood-down en-route and in 2 cases the patient had not suffered an OHCA on arrival of HEMS. 25 patients achieved return-of-spontaneous circulation (ROSC), 13 (52%) prior to HEMS arrival. The HEMS team were never first on-scene. The median time from first collapse to HEMS arrival was 31 minutes (IQR 22-40). The median time from HEMS activation to arrival on scene was 17 minutes (IQR 11.5-21). 19 patients underwent pre-hospital anaesthesia, 5 patients had electrical or chemical cardioversion and 19 patients had therapeutic hypothermia initiated by HEMS. Only 1 post-OHCA patient was transported to hospital by air. The survival to discharge rate was 6.3%. Conclusion: OHCA represents a significant proportion of HEMS call outs. HEMS most commonly attend post-ROSC OHCA patients and interventions, including pre-hospital anaesthesia and therapeutic hypothermia should be targeted to this phase. HEMS are rarely first on-scene and should only be tasked as a first response to OHCA in remote locations. HEMS may be most appropriately utilised in OHCA by only attending the scene if a patient achieves ROSC.

Elizabeth G Evans, Anthony Hudson, Emily McWhirter, Richard Lyon (2014)A review of the activation triggers and reasons for stand downs of a Helicopter Emergency Medical Service (HEMS), In: Scandinavian journal of trauma, resuscitation and emergency medicine22(Suppl 1)P5pp. P5-P5 BioMed Central
D J Lockey, R M Lyon, G E Davies (2013)A simple algorithm for the treatment of traumatic cardiac arrest, In: Scandinavian journal of trauma, resuscitation and emergency medicine21(Suppl 1)S10pp. S10-S10 BioMed Central
Richard Lyon, Andrew Conway Morris, David Caesar, Sarah Gray, Alasdair Gray (2007)Chest pain presenting to the Emergency Department—to stratify risk with GRACE or TIMI?, In: Resuscitation74(1)90pp. 90-93 Elsevier Ireland Ltd

There is a need to stratify risk rapidly in patients presenting to the Emergency Department (ED) with undifferentiated chest pain. The Global Registry of Acute Coronary Events (GRACE) and the Thrombolysis in Myocardial Infarction (TIMI) scoring systems predict outcome of adverse coronary events in patients admitted to specialist cardiac units. This study evaluates the relationship between GRACE score and outcome in patients presenting to the ED with undifferentiated chest pain and establishes whether GRACE is preferential to TIMI in stratifying risk in patients in the ED setting. Descriptive study of a consecutive sample of 1000 ED patients with undifferentiated chest pain presenting to Edinburgh Royal Infirmary, Scotland. GRACE and TIMI scores were calculated for each patient and outcomes noted at 30 days. Outcomes included ST and non-ST myocardial infarction, cardiac arrest, revascularisation, unstable angina with myocardial damage and all cause mortality at 30 days. Score and outcome were compared using receiver operator characteristic curves (AUC-ROC). The GRACE score stratifies risk accurately in patients presenting to the ED with undifferentiated chest pain (AUC-ROC 0.80 (95% CI 0.75–0.85), see Table 1). The TIMI score was found to be similarly accurate in stratifying risk in the study cohort with an AUC-ROC of 0.79 (95% CI 0.74–0.85). It was only possible to calculate a complete GRACE score in 76% ( n = 760) cases as not all the data variables were measured routinely in the ED. GRACE and TIMI are both effective in accurately stratifying risk in patients presenting to the ED with undifferentiated chest pain. The GRACE score is more complex than the TIMI score and in the ED setting TIMI may be the preferred scoring method.

R. M. Lyon, C. E. Robertson, G. R. Clegg (2010)Therapeutic hypothermia in the emergency department following out-of-hospital cardiac arrest, In: Emergency medicine journal : EMJ27(6)418pp. 418-423 BMJ Publishing Group

Out-of-hospital cardiac arrest (OHCA) is a leading cause of mortality and severe neurological disability. Recent literature suggests that mild therapeutic hypothermia (MTH) can improve survival and neurological outcome in some groups of comatose patients after cardiac arrest but uncertainty exists over the best way to implement this treatment. This review examines the evidence for the efficacy and mode of implementation of MTH after OHCA, particularly in the Emergency Department setting. A literature search was performed and all systematic reviews; human and animal randomised and non-randomised trials were screened for inclusion. Specific emphasis was placed on MTH being commenced in the prehospital and Emergency Department setting. Outcome measures were: time to reach target temperature, in-hospital mortality, neurological outcome at hospital discharge and complications of therapeutic hypothermia. Two systematic reviews found that MTH improved outcome after OHCA. Five human randomised controlled trials were identified. Two trials commenced cooling prehospital. One showed a favourable outcome but the other failed to show survival benefit. The other three trials only commenced cooling after the patient arrived in hospital and all showed improved survival for patients treated with MTH after OHCA. Evidence from animal and non-randomised studies suggests cooling should be commenced as early as possible after return of spontaneous circulation. Cold intravenous fluid was reported as a safe, effective means of cooling in the emergency setting. MTH improves patient outcome after OHCA. There is some evidence to suggest cooling should be commenced early. Cold intravenous crystalloid infusion may be the preferred cooling method in the Emergency Department.

Richard M. Lyon, Katarina Bohm, Erika Frischknecht Christensen, Theresa M. Olasveengen, Maaret Castren (2013)The inaugural European emergency medical dispatch conference - a synopsis of proceedings, In: Scandinavian journal of trauma, resuscitation and emergency medicine21(1)73pp. 73-73 Springer Nature

The inaugural European Emergency Medical Dispatch conference was held in Stockholm, Sweden, in May 2013. We provide a synopsis of the conference proceedings, highlight key topic areas of emergency medical dispatch and suggest future research priorities.

Anne E. Weaver, Ceri Hunter-Dunn, Richard M. Lyon, David Lockey, Charlotte L. Krogh (2016)The effectiveness of a ‘Code Red’ transfusion request policy initiated by pre-hospital physicians, In: Injury47(1)3pp. 3-6 Elsevier Ltd

Major trauma is a leading cause of mortality and serious morbidity. Recent approaches to life-threatening traumatic haemorrhage have emphasized the importance of early blood product transfusion. We have implemented a pre-hospital transfusion request policy where a pre-hospital physician can request the presence of a major transfusion pack on arrival at the destination trauma centre. This study was performed to establish whether three simple criteria (1) suspicion or evidence of active haemorrhage (2) systolic BP

R Lyon, G R Nimmo (2008)Gastric tubes in patients with severe brain injury, In: Critical care (London, England)12(Suppl 2)P132pp. P132-P132 BioMed Central
R. M. Lyon, S. Clarke, P. Gowens, G. Egan, G. R. Clegg (2010)Resuscitation quality assurance for out-of-hospital cardiac arrest - Setting-up an ambulance defibrillator telemetry network, In: Resuscitation81(12)1726pp. 1726-1728 Elsevier

Background: Out-of-hospital cardiac arrest (OHCA) is a leading cause of pre-hospital mortality. Chest compressions performed during cardiopulmonary resuscitation aim to provide adequate perfusion to the vital organs during cardiac arrest. Poor resuscitation technique and the quality of pre-hospital CPR influences outcome from OHCA. Transthoracic impedance (ITI) measurement is a useful tool in the assessment of the quality of pre-hospital resuscitation by ambulance crews but TT! telemetry has not yet been performed in the United Kingdom. We describe a pilot study to implement a data network to collect defibrillator TTI data via telemetry from ambulances. Methods: Prospective, observational pilot study over a 5-month period. Modems were fitted to 40 defibrillators on ambulances based in Edinburgh. TTI data was sent to a receiving computer after resuscitation attempts for OHCA. Results: 58 TTI traces were transmitted during the pilot period. Compliance with the telemetry system was high. The mean ratio of chest compressions was 73% (95% CI 69-77%), the mean chest compression rate was 128 (95% CI 122-134). The mean time interval from chest compression interruption to shock delivery was 27 s (95% CI 22-32 s). Conclusion: Trans-thoracic impedance analysis is an effective means of recording important measures of resuscitation quality including the hands-on-the-chest time, compression rate and defibrillation interval time. TTI data transmission via telemetry is straightforward, efficient and allows resuscitation data to be captured and analysed from a large geographical area. Further research is warranted on the impact of post-resuscitation reporting on the quality of resuscitation delivered by ambulance crews. (C) 2010 Elsevier Ireland Ltd. All rights reserved.

R M Lyon, G M Cowan, K M Janossy, J R Adams, A R Corfield, S Hearns (2010)In-flight cooling after out-of-hospital cardiac arrest, In: Resuscitation81(8)1041pp. 1041-1042
J E Griggs, R M Lyon, M Sherriff, J W Barrett, G Wareham, E Ter Avest, (2022)Predictive clinical utility of pre-hospital point of care lactate for transfusion of blood product in patients with suspected traumatic haemorrhage: derivation of a decision-support tool, In: Scandinavian Journal of Trauma, Resuscitation and Emergency Medicine30(1)pp. 72-72

Introduction Pre-hospital emergency medical teams can transfuse blood products to patients with suspected major traumatic haemorrhage. Common transfusion triggers based on physiological parameters have several disadvantages and are largely unvalidated in guiding pre-hospital transfusion. The addition of pre-hospital lactate (P-LACT) may overcome these challenges. To date, the clinical utility of P-LACT to guide pre-hospital blood transfusion is unclear. Methods A retrospective analysis of patients with suspected major traumatic haemorrhage attended by Air Ambulance Charity Kent Surrey Sussex (KSS) between 8 July 2017 and 31 December 2019. The primary endpoint was the accuracy of P-LACT to predict the requirement for any in-hospital (continued) transfusion of blood product. Results During the study period, 306 patients with suspected major traumatic haemorrhage were attended by KSS. P-LACT was obtained in 194 patients. In the cohort 103 (34%) patients were declared Code Red. A pre-hospital transfusion was commenced in 124 patients (41%) and in-hospital transfusion was continued in 100 (81%) of these patients, in 24 (19%) patients it was ceased. Predictive probabilities of various lactate cut-off points for requirement of in-hospital transfusion are documented. The highest overall proportion correctly classified patients were found for a P-LACT cut-point of 5.4 mmol/L (76.50% correctly classified). Based on the calculated predictive probabilities, optimal cut-off points were derived for both the exclusion- and inclusion of the need for in-hospital transfusion. A P-LACT 

E. ter Avest, L. Carenzo, R. A. Lendrum, M. D. Christian, R. M. Lyon, C. Coniglio, M. Rehn, D. J. Lockey, Z. B. Perkins (2022)Advanced interventions in the pre-hospital resuscitation of patients with non-compressible haemorrhage after penetrating injuries, In: Critical Care26184 BMC

Early haemorrhage control and minimizing the time to definitive care have long been the cornerstones of therapy for patients exsanguinating from non-compressible haemorrhage (NCH) after penetrating injuries, as only basic treatment could be provided on scene. However, more recently, advanced on-scene treatments such as the transfusion of blood products, resuscitative thoracotomy (RT) and resuscitative endovascular balloon occlusion of the aorta (REBOA) have become available in a small number of pre-hospital critical care teams. Although these advanced techniques are included in the current traumatic cardiac arrest algorithm of the European Resuscitation Council (ERC), published in 2021, clear guidance on the practical application of these techniques in the pre-hospital setting is scarce. This paper provides a scoping review on how these advanced techniques can be incorporated into practice for the resuscitation of patients exsanguinating from NCH after penetrating injuries, based on available literature and the collective experience of several helicopter emergency medical services (HEMS) across Europe who have introduced these advanced resuscitation interventions into routine practice.

Jack W. Barrett, Julia Williams, Joanna Griggs, Simon Skene, Richard Lyon (2022)What are the demographic and clinical differences between those older adults with traumatic brain injury who receive a neurosurgical intervention to those that do not? A systematic literature review with narrative synthesis, In: Brain Injuryahead-of-print(ahead-of-print)pp. 1-9 Taylor & Francis

Objectives This review aimed to identify the demographic and clinical differences between those older adults admitted directly under neurosurgical care and those that were not, and whether EMS clinicians could use these differences to improve patient triage. Methods The authors searched for papers that included older adults who had suffered a TBI and were either admitted directly under neurosurgical care or were not. Titles and abstracts were screened, shortlisting potentially eligible papers before performing a full-text review. The Newcastle-Ottawa Scale was used to assess the risk of bias. Results A total of nine studies were eligible for inclusion. A high abbreviated injury score head, Marshall score or subdural hematoma greater than 10 mm were associated with neurosurgical care. There were few differences between those patients who did and did not receive neurosurgical intervention. Conclusions Absence of guidelines and clinician bias means that differences between those treated aggressively and conservatively observed in the literature are fraught with bias. Further work is required to understand which patients would benefit from an escalation of care and whether EMS can identify these patients so they are transported directly to a hospital with the appropriate services on-site.

Objectives Prehospital rapid sequence induction (RSI) of anaesthesia is an intervention with significant associated risk. In this study, we aimed to investigate the haemodynamic response over time of a prehospital RSI protocol of fentanyl, ketamine and rocuronium in a heterogeneous population of trauma patients. Design, setting and participant We performed a retrospective study of all trauma patients who received a prehospital RSI for trauma by a physician staffed Helicopter Emergency Medical Service in the UK between 1 June 2018 and 1 February 2020. Primary outcome measure Primary outcome was defined as the incidence of clinically relevant hypotensive (systolic blood pressure (SBP) or mean arterial pressure (MAP) >20% below baseline, with an absolute SBP

D Fitzpatrick, M McKenna, E Duncan, C Laird, Richard Lyon, A Corfield (2018)Critcomms: a national cross-sectional questionnaire based study to investigate prehospital handover practices between ambulance clinicians and specialist prehospital teams in Scotland, In: Scandinavian Journal of Trauma, Resuscitation and Emergency Medicine2645 BioMed Central

Background: Poor communication during patient handover is recognised internationally as a root cause of a significant proportion of preventable deaths. Improving the accuracy and quality of handover may reduce associated mortality and morbidity. Although the practice of handover between Ambulance and Emergency Department clinicians has received some attention over recent years there is little evidence to support handover best practice within the prehospital domain. Further research is therefore urgently required to understand the most appropriate way to deliver clinical information exchange in the pre-hospital environment. We aimed to investigate current clinical information exchange practices, perceived challenges and the preferred handover mnemonic for use during transfer of high acuity patients between ambulance clinicians and specialist prehospital teams. Methods: A national, cross-sectional questionnaire study. Participants were road based ambulance clinicians (RBAC) or active members of specialist prehospital teams (SPHT) based in Scotland. Results: Over a three month study period there were 247 prehospital incidents involving specialist teams. One hundred ninety individuals completed the questionnaire; 61% [n = 116] RBAC and 39% [n = 74] SPHT. Median length of prehospital experience was 10 years (IQR 5–18). Overall current prehospital handover practices were perceived as being effective (Mdn 4.00; IQR 3–4 [1 = very ineffective - 5 = very effective]) although SPHT clinicians rated handover effectiveness slightly lower than RBAC’s (Mdn 3.00 vs 4.00, U = 1842.5, p = .03). ‘ATMIST’ (Age, Time of onset, Medical complaint/injury, Investigation, Signs and Treatment) was deemed the mnemonic of choice. The clinical variables perceived as essential for handover are not explicitly identified within the SBAR mnemonic. The most frequently reported method of recording and transferring information during handover was via memory (n = 112 and n = 120 respectively) and ‘interruptions’ were perceived as the most significant barrier to effective handover. Conclusion: While, overall, current prehospital handover practice is perceived as effective this study has identified a number of areas for improvement. These include the development of a shared mental model through system standardisation, innovations to support information recording and delivery, and the clear identification at incidents of a handover lead. Mnemonics must be carefully selected to ensure they explicitly contain the perceived essential clinical variables required for prehospital handover; the mnemonic ATMIST meets these requirements. New theoretically informed, evidence-based interventions, must be developed and tested within existing systems of care to minimise information loss and risk to patients.

Leigh Curtis, Mark Salmon, Richard Lyon (2017)The Impact of Helicopter Emergency Medical Service Night Operations in South East England, In: Air Medical Journal36(6)pp. 307-310 Elsevier

Objective This study sought to assess the impact of a helicopter emergency medical service (HEMS) capable of night operations. Methods This is a retrospective case review of all night HEMS missions attended by a charity air ambulance service in South East England over a 2-year period (October 1, 2013, to October 1, 2015). Results During the 2-year trial period, the HEMS service undertook a total of 5,004 missions and attended to 3,728 patients. Of these, 1,373 missions, or 27.4% of the total HEMS activity, were night missions. Night missions increased from year 1 (n = 617) to year 2 (n = 756). A mean of 1.9 missions per night were conducted, resulting in the treatment of 1.3 patients per night. A higher proportion of patients were transported to a major trauma center at night (64% vs. 51%, χ2 = 41.8, P < .0001). Weather conditions prevented HEMS from responding at night via air for 15% of the night operational hours. Conclusion A 2-year trial period of a night HEMS service in South East England showed the predicted activation rate, with a mean of 1.3 patients attended to per night. Patients transported to a major trauma center had a mean Injury Severity Score of 23. Further research is warranted to determine if the night HEMS service conveys a patient outcome benefit. Major trauma is a leading cause of serious morbidity and mortality.1,2 Advanced prehospital care can improve the outcome for major trauma patients.3,4 Kent, Surrey & Sussex Air Ambulance Trust (KSSAAT) delivers advanced prehospital care by deploying 2 doctor/paramedic teams by aircraft or response car. The 2 teams respond from 2 separate bases in South East England, 1 based in Surrey and 1 based in Kent. Historically, KSSAAT was operational between 0700 and 1900 hours 7 days per week. However, major trauma frequently occurs overnight, and the lack of a night helicopter emergency medical service (HEMS) was felt to be detrimental to enhanced patient care because no enhanced prehospital medical care was available overnight. Before any night HEMS service was available, KSSAAT undertook a prospective study in 2010 to explore the possible impact that a night HEMS service may have.5 This study showed the likely need of a night HEMS team being tasked 1.7 times per night during the hours of 1900 to 0700. The incidence of these predicted cases continued throughout the entire night period but with gradually decreasing frequency. Most nights of the week were predicted to have similar levels of activity with the exception of Saturday, which appeared to be the busiest night of the week. A high number of the cases identified resulted in the patient being transported to a major trauma center (MTC), indicating that HEMS activation may well have been warranted. Based on this study, KSSAAT made the decision to commit itself to exploring the options for night HEMS operations. This commitment was the start of a 3-year research, development, and training process, which culminated with the launch of a 2-year night HEMS operational trial on the night of September 26, 2013. At this point, KSSAAT became the first 24/7 helicopter-based HEMS in the United Kingdom. The purpose of this study is to review the activity, case mix, and demographics of the 2-year night HEMS trial period. We sought to compare the actual activity of the night HEMS service with the previously estimated need.

Ewoud ter Avest, Sam Taylor, Mark Wilson, Richard L Lyon (2020)Prehospital clinical signs are a poor predictor of raised intracranial pressure following traumatic brain injury, In: Emergency Medicine Journal BMJ Publishing Group

Background For the prehospital diagnosis of raised intracranial pressure (ICP), clinicians are reliant on clinical signs such as the Glasgow Coma Score (GCS), pupillary response and/or Cushing’s triad (hypertension, bradycardia and an irregular breathing pattern). This study aimed to explore the diagnostic accuracy of these signs as indicators of a raised ICP. Methods We performed a retrospective cohort study of adult patients attended by a Helicopter Emergency Medical Service (Air Ambulance Kent, Surrey Sussex), who had sustained a traumatic brain injury (TBI), requiring prehospital anaesthesia between 1 January 2016 and 1 January 2018. We established optimal cut-off values for clinical signs to identify patients with a raised ICP and investigated diagnostic accuracy for combinations of these values. Results Outcome data for 249 patients with TBI were available, of which 87 (35%) had a raised ICP. Optimal cut-off points for systolic blood pressure (SBP), heart rate (HR) and pupil diameter to discriminate patients with a raised ICP were, respectively, >160 mm Hg,5 mm. Cushing criteria (SBP >160 mm Hg and HR

JOANNE EMILY GRIGGS, JACK WILLIAM BARRETT, E. ter Avest, R. de Coverly, M Nelson, J Williams, RICHARD LYON (2021)Helicopter emergency medical service dispatch in older trauma: time to reconsider the trigger?, In: Scandinavian journal of trauma, resuscitation and emergency medicine BMC

Background Helicopter Emergency Medical Services (HEMS) respond to serious trauma and medical emergencies. Geographical disparity and the regionalisation of trauma systems can complicate accurate HEMS dispatch. We sought to evaluate HEMS dispatch sensitivity in older trauma patients by analysing critical care interventions and conveyance in a well-established trauma system. Methods All trauma patients aged 65 years that were attended by the Air Ambulance Kent Surrey Sussex over a 6-year period from 1 July 2013 to 30 June 2019 were included. Patient characteristics, critical care interventions and hospital disposition were stratified by dispatch type (immediate, interrogate and crew request). Results 1321 trauma patients aged 65 were included. Median age was 75 years [IQR 69-89]. HEMS dispatch was by immediate (32.0%), interrogation (43.5%) and at the request of ambulance clinicians (24.5%). Older age was associated with a longer dispatch interval and was significantly longer in the crew request category (37 min [34-39]) compared to immediate dispatch (6 min [5-6] (p=.001). Dispatch by crew request was common in patients with falls 2m more often resulted in immediate dispatch (p=.001). Immediate dispatch to isolated head injured patients often resulted in pre-hospital emergency anaesthesia (PHEA) (39%). However, over a third of head injured patients attended after dispatch by crew request received PHEA (36%) and a large proportion were triaged to major trauma centres (69%). Conclusions Many patients who do not fulfil the criteria for immediate HEMS dispatch need advanced clinical interventions and subsequent tertiary level care at a major trauma centre. Further studies should evaluate if HEMS activation criteria, nuanced by age-dependant triggers for mechanism and physiological parameters, optimise dispatch sensitivity and HEMS utilisation.

Adam J Boulton, Amar Mashru, Richard Lyon (2020)Oxygenation strategies prior to and during prehospital emergency anaesthesia in UK HEMS practice (PREOXY survey), In: Scandinavian journal of trauma, resuscitation and emergency medicine28 BioMed Central

Background: Maintaining effective oxygenation throughout the process of Pre-Hospital Emergency Anaesthesia (PHEA) is critical. There are multiple strategies available to clinicians to oxygenate patients both prior to and during PHEA. The optimal pre-oxygenation technique remains unclear, and it is unknown what techniques are being used by United Kingdom Helicopter Emergency Medical Services (HEMS). This study aimed to determine the current pre-and peri-PHEA oxygenation strategies used by UK HEMS services. Methods: An electronic questionnaire survey was delivered to all UK HEMS services between 05 July and 26 December 2019. Questions investigated service standard operating procedures (SOPs) and individual clinician practice regarding oxygenation strategies prior to airway instrumentation (pre-oxygenation) and oxygenation strategies during airway instrumentation (apnoeic oxygenation). Service SOPs were obtained to corroborate questionnaire replies.

R Lyon, ZB Perkins, D Chatterjee, DJ Lockey, MQ Russell (2015)Significant modification of traditional rapid sequence induction improves safety and effectiveness of pre-hospital trauma anaesthesia, In: Critical Care19(134) BioMed Central

Introduction: Rapid Sequence Induction of anaesthesia (RSI) is the recommended method to facilitate emergency tracheal intubation in trauma patients. In emergency situations, a simple and standardised RSI protocol may improve the safety and effectiveness of the procedure. A crucial component of developing a standardised protocol is the selection of induction agents. The aim of this study is to compare the safety and effectiveness of a traditional RSI protocol using etomidate and suxamethonium with a modified RSI protocol using fentanyl, ketamine and rocuronium. Methods: We performed a comparative cohort study of major trauma patients undergoing pre-hospital RSI by a physician-led Helicopter Emergency Medical Service. Group 1 underwent RSI using etomidate and suxamethonium and Group 2 underwent RSI using fentanyl, ketamine and rocuronium. Apart from the induction agents, the RSI protocol was identical in both groups. Outcomes measured included laryngoscopy view, intubation success, haemodynamic response to laryngoscopy and tracheal intubation, and mortality. Results: Compared to Group 1 (n = 116), Group 2 RSI (n = 145) produced significantly better laryngoscopy views (p = 0.013) and resulted in significantly higher first-pass intubation success (95% versus 100%; p = 0.007). A hypertensive response to laryngoscopy and tracheal intubation was less frequent following Group 2 RSI (79% versus 37%; p < 0.0001). A hypotensive response was uncommon in both groups (1% versus 6%; p = 0.05). Only one patient in each group developed true hypotension (SBP < 90 mmHg) on induction. Conclusions: In a comparative, cohort study, pre-hospital RSI using fentanyl, ketamine and rocuronium produced superior intubating conditions and a more favourable haemodynamic response to laryngoscopy and tracheal intubation. An RSI protocol using fixed ratios of these agents delivers effective pre-hospital trauma anaesthesia.

J Mohindru, J. E Griggs, R de Coverly, R. M Lyon, E ter Avest (2020)Dispatch of a helicopter emergency medicine service to patients with a sudden, unexplained loss of consciousness of medical origin, In: BMC Emergency Medicine2092 BioMed Central

Background: Sudden loss of consciousness (LOC) in the prehospital setting in the absence of cardiac arrest and seizure activity may be a challenge from a dispatcher's perspective: The aetiology is varied, with many causes being transient and mostly self-limiting, whereas other causes are potentially life threatening. In this study we aim to evaluate the dispatch of HEMS to patients with LOC of medical origin, by exploring to which patients with a LOC HEMS is dispatched, which interventions HEMS teams perform in these patients, and whether HEMS interventions can be predicted by patient characteristics. Methods: We performed retrospective cohort study of all patients with a reported unexplained LOC (e.g. not attributable to a circulatory arrest or seizures) attended by the Air Ambulance Kent, Surrey & Sussex (AAKSS), over a 4-year period (July 2013-December 2017). Primary outcome was defined as the number of HEMS-specific interventions performed in patients with unexplained LOC. Secondary outcome was the relation of clinical-and dispatch criteria with HEMS interventions being performed. Results: During the study period, 127 patients with unexplained LOC were attended by HEMS. HEMS was dispatched directly to 25.2% of the patients, but mostly (74.8%) on request of the ground ambulance crews. HEMS interventions were performed in 65% of the patients (Prehospital Emergency Anaesthesia 56%, hyperosmolar therapy 21%, antibiotic/antiviral therapy 8%, vasopressor therapy 6%) and HEMS conveyed most patients (77%) to hospital. Acute neurological pathology was a prevalent underlying cause of unexplained LOC: 38% had gross pathology on their CT-scan upon arrival in hospital. Both GCS (r=-0.60, p

J.E. Griggs, J. Jeyanathan, M. Joy, M.Q. Russell, N. Durge, D. Bootland, S. Dunn, E.D. Sausmarez, G. Wareham, A. Weaver, R.M. Lyon (2018)Mortality of civilian patients with suspected traumatic haemorrhage receiving pre-hospital transfusion of packed red blood cells compared to pre-hospital crystalloid, In: Scandinavian Journal of Trauma, Resuscitation and Emergency Medicine BMC

Background Major haemorrhage is a leading cause of mortality following major trauma. Increasingly, Helicopter Emergency Medical Services (HEMS) in the United Kingdom provide pre-hospital transfusion with blood products, although the evidence to support this is equivocal. This study compares mortality for patients with suspected traumatic haemorrhage transfused with pre-hospital packed red blood cells (PRBC) compared to crystalloid. Methods A single centre retrospective observational cohort study between 1 January 2010 and 1 February 2015. Patients triggering a pre-hospital Code Red activation were eligible. The primary outcome measure was all-cause mortality at 6 hours and 28 days, including a sub-analysis of patients receiving a major and massive transfusion. Multivariable regression models predicted mortality. Multiple Imputation (MI) was employed, and logistic regression models were constructed for all imputed datasets. Results The crystalloid (n= 103) and PRBC (n= 92) group were comparable for demographics, Injury Severity Score (p= 0.67) and mechanism of injury (p= 0.74). Observed 6 hour mortality was smaller in the PRBC group (n= 10, 10%) compared to crystalloid group (n= 19, 18%). Adjusted OR was not statistically significant (OR 0.48, CI 0.19-1.19, p= 0.11). Observed mortality at 28 days was smaller in the PRBC group (n= 21, 27%) compared to crystalloid group (n= 31, 40%), p= 0.09. Adjusted OR was not statistically significant (OR 0.66, CI 0.32-1.35, p= 0.26). A statistically significant greater proportion of the crystalloid group required a major transfusion (n= 62, 63%) compared to the PRBC group (n= 41, 46%), p= 0.02. For patients requiring a massive transfusion observed mortality was smaller in the PRBC group at 28 days (p= 0.07). Conclusion In a single centre UK HEMS study, in patients with suspected traumatic haemorrhage who received a PRBC transfusion there was an observed, but non-significant, reduction in mortality at 6 hours and 28 days, also reflected in a massive transfusion subgroup. Patients receiving pre-hospital PRBC were significantly less likely to require an in-hospital major transfusion. Further adequately powered multi-centre prospective research is required to establish the optimum strategy for pre-hospital volume replacement in patients with traumatic haemorrhage.

Aim In this study, we aimed to investigate the efficacy of a helicopter emergency medical service (HEMS) facilitated pathway for in-hospital extracorporeal cardiopulmonary resuscitation (ECPR) for patients with an out of hospital cardiac arrest (OHCA) in a semi-rural setting. Methods We retrospectively reviewed all patients with an OHCA attended by a UK HEMS service between 1 January 2018 and 20 September 2021, when a dedicated ECPR pathway was in effect to facilitate transport of eligible patients to the nearest ECLS centre. The primary endpoint was the number of patients meeting ECPR eligibility criteria at three pre-defined time points: at HEMS dispatch, during on-scene evaluation and upon arrival in hospital. Results During the study period, 162 patients attended met ECPR pathway dispatch criteria. After on-scene evaluation, 74 patients (45%) had a return of spontaneously circulation before arrival of HEMS, 60 (37%) did not meet eligibility criteria regarding initial rhythm or etiology of the OHCA, and 15 (9%) had deteriorated (mainly into asystole) and were no longer suitable candidates upon arrival of HEMS. Eleven patients were eligible for ECPR and transported to hospital in arrest, and a further two patients were transported for post-ROSC ECLS. Nine patients deteriorated during transport and were no longer suitable ECPR candidates upon arrival. ECLS was successfully initiated in two patients (one intra-arrest, and one post-ROSC). Conclusion In-hospital ECPR is of limited value for patients with refractory OHCA in a semi-rural setting, even when a dedicated pathway is in place. Potentially eligible patients often cannot be transported within an appropriate timeframe and/or deteriorate before arrival in hospital.

H. Tucker, J.E. Griggs, M. Gavrilovski, S. Rahman, C Simpson, Richard Lyon, A Hudson (2023)Pre-hospital management of penetrating neck injuries: an evaluation of practice, In: Air medical journal Elsevier

Background Penetrating neck injuries (PNIs) can occur at multiple anatomical sites and involve airway, nerve, vascular and gastrointestinal structures. They pose a unique challenge to clinicians, especially in the pre-hospital setting. Published guidance on the pre-hospital management of PNIs is limited, and there is no review of current pre-hospital practice. Method A retrospective electronic case notes review of PNIs managed within one UK Helicopter Emergency Medical Service (HEMS) over a 7-year period was undertaken. Data was collected on zone of injury, mechanism of injury, pre-hospital times, patient demographics, pre-hospital interventions and on-scene mortality. Results 98 patients met study inclusion criteria, of which 40% had zone II neck injuries. 83% were male with a mean age of 42. The predominant injury mechanism was interpersonal violence (51%), followed by self-harm (47%). 15% underwent pre-hospital emergency anaesthesia, 17% underwent pre-hospital blood transfusion and 30% had a haemostatic dressing applied. No patients underwent cervical spine immobilisation. 1% underwent resuscitative thoracotomy. 5% were pronounced life extinct after HEMS arrival following interventions by the HEMS team. Conclusion Time critical and emergent interventions in this select patient population must be minimal and focus on optimizing care during rapid transfer to hospital. Airway and haemorrhagic pathologies must be managed, often concomitantly. Targeted injury prevention to reduce inter-personal violence must ensue. The author group intend to devise a National Delphi and derive consensus guidelines for the management of pre-hospital PNIs.

P. Leitch, A. L. Hudson, J. E. Griggs, R. Stolmeijer, R. M. Lyon, E. ter Avest, Air Ambulance Kent Surrey Sussex (2021)Incidence of hyperoxia in trauma patients receiving pre-hospital emergency anaesthesia: results of a 5-year retrospective analysis, In: Scandinavian journal of trauma, resuscitation and emergency medicine29134 BMC

Background Previous studies have demonstrated an association between hyperoxia and increased mortality in various patient groups. Critically unwell and injured patients are routinely given high concentration oxygen in the pre-hospital phase of care. We aim to investigate the incidence of hyperoxia in major trauma patients receiving pre-hospital emergency anesthesia (PHEA) in the pre-hospital setting and determine factors that may help guide clinicians with pre-hospital oxygen administration in these patients. Methods A retrospective cohort study was performed of all patients who received PHEA by a single helicopter emergency medical service (HEMS) between 1 October 2014 and 1 May 2019 and who were subsequently transferred to one major trauma centre (MTC). Patient and treatment factors were collected from the electronic patient records of the HEMS service and the MTC. Hyperoxia was defined as a PaO2 > 16 kPA on the first arterial blood gas analysis upon arrival in the MTC. Results On arrival in the MTC, the majority of the patients (90/147, 61.2%) had severe hyperoxia, whereas 30 patients (20.4%) had mild hyperoxia and 26 patients (19.7%) had normoxia. Only 1 patient (0.7%) had hypoxia. The median PaO2 on the first arterial blood gas analysis (ABGA) after HEMS handover was 36.7 [IQR 18.5–52.2] kPa, with a range of 7.0–86.0 kPa. SpO2 pulse oximetry readings before handover were independently associated with the presence of hyperoxia. An SpO2 ≥ 97% was associated with a significantly increased odds of hyperoxia (OR 3.99 [1.58–10.08]), and had a sensitivity of 86.7% [79.1–92.4], a specificity of 37.9% [20.7–57.8], a positive predictive value of 84.5% [70.2–87.9] and a negative predictive value of 42.3% [27.4–58.7] for the presence of hyperoxemia. Conclusion Trauma patients who have undergone PHEA often have profound hyperoxemia upon arrival at hospital. In the pre-hospital setting, where arterial blood gas analysis is not readily available a titrated approach to oxygen therapy should be considered to reduce the incidence of potentially harmful tissue hyperoxia.

J Jeyanathan, D Bootland, A Al-Rais, J Leung, J Wijesuriya, L Banks, T Breen, R DeCoverly, L Curtis, A McHenry, D Wright, J E Griggs, R M Lyon (2022)Lessons learned from the first 50 COVID-19 critical care transfer missions conducted by a civilian UK Helicopter Emergency Medical Service team, In: Scandinavian Journal of Trauma, Resuscitation and Emergency Medicine30(6) BMC

Background The COVID-19 pandemic has placed exceptional demand on Intensive Care Units, necessitating the critical care transfer of patients on a regional and national scale. Performing these transfers required specialist expertise and involved moving patients over significant distances. Air Ambulance Kent Surrey Sussex created a designated critical care transfer team and was one of the first civilian air ambulances in the United Kingdom to move ventilated COVID-19 patients by air. We describe the practical set up of such a service and the key lessons learned from the first 50 transfers. Methods Retrospective review of air critical care transfer service set up and case review of first 50 transfers. Results We describe key elements of the critical care transfer service, including coordination and activation; case interrogation; workforce; training; equipment; aircraft modifications; human factors and clinical governance. A total of 50 missions are described between 18 December 2020 and 1 February 2021. 94% of the transfer missions were conducted by road. The mean age of these patients was 58 years (29–83). 30 (60%) were male and 20 (40%) were female. The mean total mission cycle (time of referral until the time team declared free at receiving hospital) was 264 min (range 149–440 min). The mean time spent at the referring hospital prior to leaving for the receiving unit was 72 min (31–158). The mean transfer transit time between referring and receiving units was 72 min (9–182). Conclusion Critically ill COVID-19 patients have highly complex medical needs during transport. Critical care transfer of COVID-19-positive patients by civilian HEMS services, including air transfer, can be achieved safely with specific planning, protocols and precautions. Regional planning of COVID-19 critical care transfers is required to optimise the time available of critical care transfer teams.

D Fitzpatrick, M McKenna, E Duncan, C Laird, Richard Lyon, A Corfield (2018)Critcomms: A national cross-sectional questionnaire based study to investigate prehospital handover practices between Ambulance Clinicians and Specialist Prehospital Teams in Scotland., In: Scandinavian Journal of Trauma, Resuscitation and Emergency Medicine2645 BioMed Central

Background: Poor communication during patient handover is recognised internationally as a root cause of a significant proportion of preventable deaths. Improving the accuracy and quality of handover may reduce associated mortality and morbidity. Although the practice of handover between Ambulance and Emergency Department clinicians has received some attention over recent years there is little evidence to support handover best practice within the prehospital domain. Further research is therefore urgently required to understand the most appropriate way to deliver clinical information exchange in the pre-hospital environment. We aimed to investigate current clinical information exchange practices, perceived challenges and the preferred handover mnemonic for use during transfer of high acuity patients between ambulance clinicians and specialist prehospital teams. Methods: A national, cross-sectional questionnaire study. Participants were road based ambulance clinicians (RBAC) or active members of specialist prehospital teams (SPHT) based in Scotland. Results: Over a three month study period there were 247 prehospital incidents involving specialist teams. One hundred ninety individuals completed the questionnaire; 61% [n = 116] RBAC and 39% [n = 74] SPHT. Median length of prehospital experience was 10 years (IQR 5–18). Overall current prehospital handover practices were perceived as being effective (Mdn 4.00; IQR 3–4 [1 = very ineffective - 5 = very effective]) although SPHT clinicians rated handover effectiveness slightly lower than RBAC’s (Mdn 3.00 vs 4.00, U = 1842.5, p = .03). ‘ATMIST’ (Age, Time of onset, Medical complaint/injury, Investigation, Signs and Treatment) was deemed the mnemonic of choice. The clinical variables perceived as essential for handover are not explicitly identified within the SBAR mnemonic. The most frequently reported method of recording and transferring information during handover was via memory (n = 112 and n = 120 respectively) and ‘interruptions’ were perceived as the most significant barrier to effective handover. Conclusion: While, overall, current prehospital handover practice is perceived as effective this study has identified a number of areas for improvement. These include the development of a shared mental model through system standardisation, innovations to support information recording and delivery, and the clear identification at incidents of a handover lead. Mnemonics must be carefully selected to ensure they explicitly contain the perceived essential clinical variables required for prehospital handover; the mnemonic ATMIST meets these requirements. New theoretically informed, evidence-based interventions, must be developed and tested within existing systems of care to minimise information loss and risk to patients.

GA Sunde, M Sandberg, Richard Lyon, K Fredriksen, B Burns, KO Hufthammer, J Røislien, A Soti, H Jäntti, D Lockey, J-K Heltne, SJM Sollid (2017)Hypoxia and hypotension in patients intubated by physician staffed helicopter emergency medical services - a prospective observational multi-centre study, In: BMC Emergency Medicine17(22) BioMed Central

Background: The effective treatment of airway compromise in trauma and non-trauma patients is important. Hypoxia and hypotension are predictors of negative patient outcomes and increased mortality, and may be important quality indicators of care provided by emergency medical services. Excluding cardiac arrests, critical trauma and non-trauma patients remain the two major groups to which helicopter emergency medical services (HEMS) are dispatched. Several studies describe the impact of pre-hospital hypoxia or hypotension on trauma patients, but few studies compare this in trauma and non-trauma patients. The primary aim was to describe the incidence of pre-hospital hypoxia and hypotension in the two groups receiving pre-hospital tracheal intubation (TI) by physician-staffed HEMS. Methods: Data were collected prospectively over a 12-month period, using a uniform Utstein-style airway template. Twenty-one physician-staffed HEMS in Europe and Australia participated. We compared peripheral oxygen saturation and systolic blood pressure before and after definitive airway management. Data were analysed using Cochran–Mantel–Haenszel methods and mixed-effects models. Results: Eight hundred forty three trauma patients and 422 non-trauma patients receiving pre-hospital TI were included. Non-trauma patients had significantly lower predicted mean pre-intervention SpO2 compared to trauma patients. Post-intervention and admission SpO2 for the two groups were comparable. However, 3% in both groups were still hypoxic at admission. For hypotension, the differences between the groups were less prominent. However, 9% of trauma and 10% of non-trauma patients were still hypotensive at admission. There was no difference in short-term survival between trauma (97%) and non-trauma patients (95%). Decreased level of consciousness was the most frequent indication for TI, and was associated with increased survival to hospital (cOR 2.8; 95% CI: 1.4–5.4).Conclusions: Our results showed that non-trauma patients had a higher incidence of hypoxia before TI than trauma patients, but few were hypoxic at admission. The difference for hypotension was less prominent, but one in ten patients were still hypotensive at admission. Further investigations are needed to identify reversible causes that may be corrected to improve haemodynamics in the pre-hospital setting. We found high survival rates to hospital in both groups, suggesting that physician-staffed HEMS provide high-quality emergency airway management in trauma and non-trauma patients. Trial registration: Clinicaltrials.gov Identifier: NCT01502111. Registered 22 December 2011

David Fitzpatrick, Michael McKenna, Edward AS Duncan, Colville Laird, Richard Lyon, Alasdair Corfield (2018)Critcomms: A national cross-sectional questionnaire based study to investigate prehospital handover practices between Ambulance Clinicians and Specialist Prehospital Teams in Scotland, In: Scandinavian Journal of Trauma, Resuscitation and Emergency Medicine26(45)pp. 1-11 BioMed Central

Background Poor communication during patient handover is recognised internationally as a root cause of a significant proportion of preventable deaths. Improving the accuracy and quality of handover may reduce associated mortality and morbidity. Although the practice of handover between Ambulance and Emergency Department clinicians has received some attention over recent years there is little evidence to support handover best practice within the prehospital domain. Further research is therefore urgently required to understand the most appropriate way to deliver clinical information exchange in the pre-hospital environment. We aimed to investigate current clinical information exchange practices, perceived challenges and the preferred handover mnemonic for use during transfer of high acuity patients between ambulance clinicians and specialist prehospital teams. Methods A national, cross-sectional questionnaire study. Participants were road based ambulance clinicians (RBAC) or active members of specialist prehospital teams (SPHT) based in Scotland. Results Over a three month study period there were 247 prehospital incidents involving specialist teams. 190 individuals completed the questionnaire; 61% [n=116] RBAC and 39% [n=74] SPHT. Median length of prehospital experience was 10 years (IQR 5-18). Overall current prehospital handover practices were perceived as being effective (Mdn 4.00; IQR 3-4 [1= very ineffective - 5 = very effective]) although SPHT clinicians rated handover effectiveness slightly lower than RBAC's (Mdn 3.00 vs 4.00, U = 1842.5, p = .03). 'ATMIST' (Age, Time of onset, Medical complaint/injury, Investigation, Signs and Treatment) was deemed the mnemonic of choice. The clinical variables perceived as essential for handover are not explicitly identified within the SBAR mnemonic. The most frequently reported method of recording and transferring information during handover was via memory (n=112 and n=120 respectively) and ‘interruptions’ were perceived as the most significant barrier to effective handover. Conclusion While, overall, current prehospital handover practice is perceived as effective this study has identified a number of areas for handover improvement. These include the development of a shared mental model through system standardisation, innovations to support information recording and delivery, and the clear identification at incidents of a handover lead. Mnemonics must be carefully selected to ensure they explicitly contain the perceived essential clinical variables required for prehospital handover; the mnemonic ATMIST meets these requirements. New theoretically informed, evidence-based interventions, must be developed and tested within existing systems of care to minimise information loss and risk to patients.

K Hunter, A S McHenry, L Curtis, E Ter Avest, S Mitchinson, J E Griggs, R M Lyon, (2021)Feasibility of pre-hospital emergency anaesthesia in the cabin of an AW169 helicopter wearing personal protective equipment during COVID-19, In: Air Medical Journal Elsevier

Objective Pre-hospital emergency anaesthesia in the form of rapid sequence intubation (RSI) is a critical intervention delivered by advanced pre-hospital critical care teams. Our previous simulation study determined the feasibility of in-aircraft RSI. We now examine whether this feasibility is preserved in a simulated setting, when clinicians wear personal protective equipment (PPE) for aerosol-generating procedures (AGP) for in-aircraft, on-the-ground RSI. Methods Air Ambulance Kent Surrey Sussex is a Helicopter Emergency Medical Service (HEMS) which utilises an AW169 cabin simulator. Wearing full AGP PPE (eye protection, FFP3 mask, gown, gloves), 10 doctor-paramedic teams performed RSI in a standard “can intubate, can ventilate” scenario and a “can't intubate, can't oxygenate” (CICO) scenario. Pre-specified timings were reported, and participant feedback was sought by questionnaire. Results RSI was most commonly performed by direct laryngoscopy and was successfully achieved in all scenarios. Time to completed endotracheal intubation (ETI) was fastest (287s) in the standard scenario and slower (370s, p=.01) in the CICO scenario. Time to ETI was not significantly delayed by wearing PPE in the standard (p=.19) or CICO variant (p=.97). Communication challenges, equipment complications and PPE difficulties were reported, but ways to mitigate these also reported. Conclusion In-aircraft RSI (aircraft on-the-ground) whilst wearing PPE for AGPs had no significant impact on time to successful completion of ETI in a simulated setting. Patient safety is paramount in civilian HEMS, but the adoption of in-aircraft RSI could confer significant patient benefit in terms of pre-hospital time saving and further research is warranted.

M. Gavrilovski, J. E. Griggs, E. ter Avest, R. M. Lyon (2021)The contribution of helicopter emergency medical services in the pre-hospital care of penetrating torso injuries in a semi-rural setting, In: Scandinavian Journal of Trauma, Resuscitation and Emergency Medicine29112 BMC

Background Although the merit of pre-hospital critical care teams such as Helicopter Emergency Medical Services (HEMS) has been universally recognized for patients with penetrating torso injuries who present with unstable physiology, the potential merit in patients initially presenting with stable physiology is largely undetermined. The ability to predict the required pre-hospital interventions patients may have important implications for HEMS tasking, especially when transport times to definitive care are prolonged. Methods We performed a retrospective cohort study of patients who sustained a penetrating torso injury and were attended by the Air Ambulance Kent Surrey Sussex (AAKSS) over a 6-year period. Primary outcome was defined as the percentage of patients with penetrating torso injuries requiring HEMS-specific interventions anytime between HEMS arrival and arrival at hospital. Secondary outcomes were the association of individual patient- and injury characteristics with the requirement for HEMS interventions. Results During the study period 363 patients met inclusion criteria. 90% of patients were male with a median age of 30 years. 99% of penetrating trauma incident occurred more than 10-min drive from a Major Trauma Centre (MTC). Presenting GCS was > 13 in 83% of patients. Significant hemodynamic- or ventilatory compromise was present in more than 25% of the patients. Traumatic cardiac arrest was present in 34 patients (9.4%), profound hypotension with SBP 

Craig Prentice, Jeyasankar Jeyanathan, Richard De Coverly, Julia Williams, Richard Lyon (2018)Emergency medical dispatch recognition, clinical intervention and outcome of patients in traumatic cardiac arrest from major trauma: an observational study, In: BMJ Open8(9)e022464 BMJ Publishing Group

Objectives The aim of this study is to describe the demographics of reported traumatic cardiac arrest (TCA) victims, prehospital resuscitation and survival to hospital rate. Setting Helicopter Emergency Medical Service (HEMS) in south-east England, covering a resident population of 4.5 million and a transient population of up to 8 million people. Participants Patients reported on the initial 999 call to be in suspected traumatic cardiac arrest between 1 July 2016 and 31 December 2016 within the trust’s geographical region were identified. The inclusion criteria were all cases of reported TCA on receipt of the initial emergency call. Patients were subsequently excluded if a medical cause of cardiac arrest was suspected. Outcome measures Patient records were analysed for actual presence of cardiac arrest, prehospital resuscitation procedures undertaken and for survival to hospital rates. Results 112 patients were reported to be in TCA on receipt of the 999/112 call. 51 (46%) were found not to be in TCA on arrival of emergency medical services. Of the ‘not in TCA cohort’, 34 (67%) received at least one advanced prehospital medical intervention (defined as emergency anaesthesia, thoracostomy, blood product transfusion or resuscitative thoracotomy). Of the 61 patients in actual TCA, 10 (16%) achieved return-of-spontaneous circulation. In 45 (88%) patients, the HEMS team escorted the patient to hospital. Conclusion A significant proportion of patients reported to be in TCA on receipt of the emergency call are not in actual cardiac arrest but are critically unwell requiring advanced prehospital medical intervention. Early activation of an enhanced care team to a reported TCA call allows appropriate advanced resuscitation. Further research is warranted to determine which interventions contribute to improved TCA survival.

E. ter Avest, J. Griggs, C. Prentice, J. Jeyanathan, R.M. Lyon (2019)Out-of-hospital cardiac arrest following trauma: What does a helicopter emergency medical service offer?, In: Resuscitation135pp. 73-79 Elsevier

Introduction Helicopter emergency medical services (HEMS) are often dispatched to patients in traumatic cardiac arrest (TCA) as they can provide treatments and advanced interventions in the pre-hospital environment that have the potential to contribute to an increased survival. This study, aimed to investigate the added value of HEMS in the treatment of TCA. Methods We performed a retrospective cohort study of all patients with a pre-hospital TCA who were attended by a non-urban HEMS (Kent, Surrey and Sussex Air Ambulance trust) between July 1st 2013 and May 1st 2018. We investigated how many patients got return of spontaneous circulation (ROSC) at scene, which HEMS specific advanced interventions were performed in these patients, and how these interventions were related to ROSC. Results During the study period 263 patients with a TCA were attended by HEMS with an average response time of 30 min [range 13–109]. 51 patients (20%) regained ROSC at scene (28 before- and 23 after arrival of HEMS). The HEMS specific interventions of blood product administration (OR 8.54 [2.84–25.72]), and RSI (2.95 [1.32–6.58]) were positively associated with ROSC. Most patients who had a ROSC had one or more HEMS specific interventions being performed – RSI (n = 19, 37%), blood product administration (n = 32, 62%), thoracostomies (n = 36, 71%) and thoracotomy (n = 1, 2%). HEMS also delivered other important interventions to these patients as IV/IO access (n = 20, 39.2%) and endotracheal intubation without drugs (n = 9, 17.6%). Conclusion HEMS teams should be involved in the treatment of patients with a TCA, even in non-urban areas with prolonged response times, as they provide knowledge and skills that contribute to regaining and maintaining a sustained ROSC in this critically ill and injured cohort of patients.

Aditya C. Shekhar, Ira J. Blumen, RICHARD LYON (2022)Mechanical Cardiopulmonary Resuscitation's Role in Helicopter Air Ambulances: A Narrative Review, In: Air medical journal Elsevier

Helicopter emergency medical services (HEMS) frequently respond to out-of-hospital cardiac arrest (OHCA) situations. Some have speculated mechanical cardiopulmonary resuscitation (mCPR) may be able to rectify the inadequacy of human performance of cardiopulmonary resuscitation (CPR) during transport. A number of studies have examined the performance of mCPR devices in the air medical setting specifically. Many aspects of the HEMS environment seem uniquely conducive to mCPR, and a growing body of research seems to suggest mCPR holds promise for the treatment of cardiac arrest by HEMS clinicians. Simulation studies show that mCPR leads to improved CPR performance compared with manual CPR in HEMS. Case reports and the experience of several HEMS programs suggest that mCPR can be effectively integrated into HEMS care. However, further research regarding the effectiveness of mCPR in the HEMS environment and in general cardiac arrest care is needed.

Lucie Ollis, Simon S Skene, Julia Williams, Richard Lyon, Cath Taylor, Kate Bennett-Eastley, Mark Cropley, Heather Gage, Janet Holah, Jill Maben, Carin Magnusson, Craig Mortimer, LUCIE BEATRICE OLLIS, Scott Munro (2023)The SEE-IT Trial: emergency medical services Streaming Enabled Evaluation In Trauma: study protocol for an interventional feasibility randomised controlled trial, In: BMJ open13e072877 British Medical Journal Publishing Group

Introduction Accurate and timely dispatch of emergency medical services (EMS) is vital due to limited resources and patients’ risk of mortality and morbidity increasing with time. Currently, most UK emergency operations centres (EOCs) rely on audio calls and accurate descriptions of the incident and patients’ injuries from lay 999 callers. If dispatchers in the EOCs could see the scene via live video streaming from the caller’s smartphone, this may enhance their decision making and enable quicker and more accurate dispatch of EMS. The main aim of this feasibility randomised controlled trial (RCT) is to assess the feasibility of conducting a definitive RCT to assess the clinical and cost effectiveness of using live streaming to improve targeting of EMS.Methods and analysisThe SEE-IT Trial is a feasibility RCT with a nested process evaluation. The study also has two observational substudies: (1) in an EOC that routinely uses live streaming to assess the acceptability and feasibility of live streaming in a diverse inner-city population and (2) in an EOC that does not currently use live streaming to act as a comparator site regarding the psychological well-being of EOC staff using versus not using live streaming.Ethics and disseminationThe study was approved by the Health Research Authority on 23 March 2022 (ref: 21/LO/0912), which included NHS Confidentiality Advisory Group approval received on 22 March 2022 (ref: 22/CAG/0003). This manuscript refers to V.0.8 of the protocol (7 November 2022). The trial is registered with the ISRCTN (ISRCTN11449333). The first participant was recruited on 18 June 2022.The main output of this feasibility trial will be the knowledge gained to help inform the development of a large multicentre RCT to evaluate the clinical and cost effectiveness of the use of live streaming to aid EMS dispatch for trauma incidents.Trial registration numberISRCTN11449333.

We read the article “The effect of pre-hospital critical care on survival following out of hospital cardiac arrest: A prospective observational study”1 with great interest. The authors should be complimented for their effort to answer the question whether or not pre-hospital critical care teams contribute to the survival of out-of-hospital cardiac arrest (OHCA) patients. In their study, they could not demonstrate a positive association between pre-hospital critical care and survival to hospital discharge, which was their primary endpoint. Although a couple of reasons for the lack of benefit from pre-hospital critical care for OHCA are provided, we think several important explanations remain unmentioned in the article.

Allan S. McHenry, Leigh Curtis, Ewoud ter Avest, Malcolm Q. Russell, Amy V. Halls, Sophie Mitchinson, Joanne E. Griggs, Richard M. Lyon (2020)Feasibility of Prehospital Rapid Sequence Intubation in the Cabin of an AW169 Helicopter, In: Air Medical Journal Elsevier

Objective Prehospital rapid sequence intubation (RSI) is an important aspect of prehospital care for helicopter emergency medical services (HEMS). This study examines the feasibility of in-aircraft (aircraft on the ground) RSI in different simulated settings. Methods Using an AW169 aircraft cabin simulator at Air Ambulance Kent Surrey Sussex, 3 clinical scenarios were devised. All required RSI in a “can intubate, can ventilate” (easy variant) and a “can't intubate, can't ventilate” scenario (difficult variant). Doctor-paramedic HEMS teams were video recorded, and elapsed times for prespecified end points were analyzed. Results Endotracheal intubation (ETI) was achieved fastest outside the simulator for the easy variant (median = 231 seconds, interquartile range = 28 seconds). Time to ETI was not significantly longer for in-aircraft RSI compared with RSI outside the aircraft, both in the easy (p = .14) and difficult variant (p = .50). Wearing helmets with noise distraction did not impact the time to intubation when compared with standard in-aircraft RSI, both in the easy (p = .28) and difficult variant (p = .24). Conclusion In-aircraft, on-the-ground RSI had no significant impact on the time to successful completion of ETI. Future studies should prospectively examine in-cabin RSI and explore the possibilities of in-flight RSI in civilian HEMS services.

Following the return of spontaneous circulation after cardiac arrest, neurological dysfunction, airway or ventilatory compromise can impede transport to early percutaneous coronary intervention, necessitating pre-hospital or emergency department anaesthesia to facilitate this procedure. There are no published reports of the ideal induction agents in these patients. We sought to describe haemodynamic changes associated with a midazolam (0.1mg/kg) fentanyl (2mcg/kg) rocuronium (1mg/kg) regimen developed from expert opinion, and adherence to the protocol by our pre-hospital teams. We performed a retrospective review of electronic vital-signs recorded during induction of return of spontaneous circulation patients over a 30-month period. We analysed the changes in systolic blood pressure and heart rate using a repeated-measures design, and the rate of new hypotension or hypertension. Sixty four patients had four consecutive measurements for analysis (one pre-induction and three post-induction). Systolic blood pressure was significantly lower than the pre-induction value at all three post-induction measurements. Heart rate did not differ between any time-point. New episodes of hypotension (systolic pressure

Cath Taylor, Lucie Ollis, Richard M. Lyon, Julia Williams, Simon S. Skene, Kate Bennett, Matthew Glover, Scott Munro, Craig Mortimer, Jill Maben, Carin Magnusson, Heather Gage, Mark Cropley, Janet Holah (2024)The SEE-IT Trial: Emergency Medical Services Streaming Enabled Evaluation In Trauma: a feasibility randomised controlled trial, In: Scandinavian Journal of Trauma, Resuscitation and Emergency Medicine BMC

Background Use of bystander video livestreaming from scene to Emergency Medical Services (EMS) is becoming increasingly common to aid decision making about the resources required. Possible benefits include earlier, more appropriate dispatch and clinical and financial gains, but evidence is sparse. Methods A feasibility randomised controlled trial with an embedded process evaluation and exploratory economic evaluation where working shifts during six trial weeks were randomised 1:1 to use video livestreaming during eligible trauma incidents (using GoodSAM Instant-On-Scene) or standard care only. Pre-defined progression criteria were: (1) ≥70% callers (bystanders) with smartphones agreeing and able to activate live stream; (2) ≥50% requests to activate resulting in footage being viewed; (3) Helicopter Emergency Medical Services (HEMS) stand-down rate reducing by ≥10% as a result of live footage; (4) no evidence of psychological harm in callers or staff/dispatchers. Observational sub-studies included (i) an inner-city EMS who routinely use video livestreaming to explore acceptability in a diverse population; and (ii) staff wellbeing in an EMS not using video livestreaming for comparison to the trial site. Results Sixty-two shifts were randomised, including 240 incidents (132 control; 108 intervention). Livestreaming was successful in 53 incidents in the intervention arm. Patient recruitment (to determine appropriateness of dispatch), and caller recruitment (to measure potential harm) were low (58/269, 22% of patients; 4/244, 2% of callers). Two progression criteria were met: (1) 86% of callers with smartphones agreed and were able to activate livestreaming; (2) 85% of requests to activate livestreaming resulted in footage being obtained; and two were indeterminate due to insufficient data: (3) 2/6 (33%) HEMS stand down due to livestreaming; (4) no evidence of psychological harm from survey, observations or interviews, but insufficient survey data from callers or comparison EMS site to be confident. Language barriers and older age were reported in interviews as potential challenges to video livestreaming by dispatchers in the inner-city EMS. Conclusions Progression to a definitive RCT is supported by these findings. Bystander video livestreaming from scene is feasible to implement, acceptable to both 999 callers and dispatchers, and may aid dispatch decision-making. Further assessment of unintended consequences, benefits and harm is required. Trial registration Trial registration: ISRCTN 11449333 (22 March 2022). https://www.isrctn.com/ISRCTN11449333

L. Curtis, E. ter Avest, J. Griggs, J. Wiliams, R. M. Lyon (2020)The ticking clock: does actively making an enhanced care team aware of the passage of time improve pre-hospital scene time following traumatic incidents?, In: Scandinavian Journal of Trauma, Resuscitation and Emergency Medicine2831 BMC

Introduction Pre-hospital enhanced care teams like Helicopter Emergency Medical Services (HEMS) are often dispatched to major trauma patients, including patients with traumatic brain injuries and those with major haemorrhage. For these patients, minimizing the time to definitive care is vital. The aim of this study was to determine whether increased awareness of elapsed on scene time produces a relevant time performance improvement for major trauma patients attended by HEMS, and weather introducing such a timer was feasible and acceptable to clinicians. Methods We performed a prospective cohort study of all single casualty traumatic incidents attended by Air Ambulance Kent Surrey Sussex (AAKSS) between 15 October 2016 and 23 May 2017 to test if introduction of a prompting scene timer within the service resulted in a reduction in pre-hospital scene times. Results The majority of the patients attended were male (74%) and sustained blunt trauma (92%). Overall, median scene time was 25.5 [IQR16.3] minutes before introduction of the scene timer and 23.0 [11.0] minutes after introduction, p = 0.13). Scene times for patients with a GCS ˂ 8 and for patients requiring prehospital anaesthesia were significantly lower after introduction of the timer (28 [IQR 14] vs 25 [1], p = 0.017 and 34 [IQR 13] vs 28 [IQR11] minutes, p = 0.007 respectively). The majority of clinicians felt the timer made them more aware of passing time (91%) but that this had not made a difference to scene time (62%) or their practice (57%). Conclusion Audible scene timers may have the potential to reduce pre-hospital scene time for certain single casualty trauma patients treated by a HEMS team, particularly for those patients needing pre-hospital anaesthesia. Regular use of on-scene timers may improve outcomes by reducing time to definitive care for certain subgroups of trauma patients.

Duncan Bootland, Caroline Rose, Jack W Barrett, Richard Lyon (2019)Pre-hospital anaesthesia and assessment of head injured patients presenting to a UK Helicopter Emergency Medical Service with a high Glasgow Coma Scale: a cohort study, In: BMJ Open9(2)e023307pp. 1-6 BMJ Publishing Group

Objectives Patients who sustain a head injury but maintain a Glasgow Coma Scale (GCS) of 13–15 may still be suffering from a significant brain injury. We aimed to assess the appropriateness of triage and decision to perform prehospital rapid sequence induction (RSI) in patients attended by a UK Helicopter Emergency Medical Service (HEMS) following head injury. Design A retrospective cohort study of patients attended by Kent Surrey & Sussex Air Ambulance Trust (KSSAAT) HEMS. Setting A mixed urban and rural area of 4.5 million people in South East England. Participants GCS score of 13, 14 or 15 on arrival of the HEMS team and clinical findings suggesting head injury. Patients accompanied by the HEMS team to hospital (‘Escorted’), and those that were ‘Assisted’ but conveyed by the ambulance service were reviewed. No age restrictions to inclusion were set. Primary outcome measure Significant brain injury. Secondary outcome measure Recognition of patients requiring prehospital anaesthesia for head injury. Results Of 517 patients, 321 had adequate follow-up, 69% of these were Escorted, 31% Assisted. There was evidence of intracranial injury in 13.7% of patients and clinically important brain injury in 7.8%. There was no difference in the rate of clinically important brain injury between Escorted and Assisted patients (p=0.46). Nineteen patients required an RSI by the HEMS team and this patient group was significantly more likely to have clinically important brain injury (p=0.04). Conclusion In patients attended by a UK HEMS service with a head injury and a GCS of 13–15, a small but significant proportion had a clinically important brain injury and a proportion were appropriately recognised as requiring prehospital RSI. For patients deemed not to need a HEMS intervention, differentiating between those with and without clinically important brain injury appears challenging.

Ewoud ter Avest, Emily McWhirter, Sophy Dunn, Joanne E Griggs, Richard M Lyon (2018)Pre-hospital death following traumatic cardiac arrest: do we get the feedback we need to improve our performance?, In: Air Medical Journal Elsevier

Objectives: The aim of this study was to establish if in patients who die at scene as a result of a traumatic cardiac arrest (TCA), their cause of death could be determined through coroners reports, and to ascertain the quality of the feedback provided. Methods: This is a retrospective study of all patients presenting in TCA who were attended by the Kent, Surrey and Sussex Air Ambulance trust between 1 January 2015 and 30 June 2016. Results: In total, 159 patients were attended during the study period. PM reports could not be obtained for 37 patients, mainly due to unestablished identities at scene. Forty of the 122 reports obtained were full PM reports, 3 were inquest reports and for 79 patients only their (presumed) cause of death was provided. A specific cause of death was provided for 68 patients, whereas in the remaining 54 patients the cause of death was given as “multiple injuries”. In 32% of the patients with a full PM report, injuries were identified during the post mortem examination that had not been noted on scene. Conclusion: Feedback from coroners to pre-hospital teams after patients die as a result of a TCA is important, but currently suboptimal.

Scott Munro, Mark Joy, Richard de Coverly, Mark Salmon, Julia Williams, Richard M. Lyon (2018)A novel method of non-clinical dispatch is associated with a higher rate of critical Helicopter Emergency Medical Service intervention, In: Scandinavian Journal of Trauma, Resuscitation and Emergency Medicine26(84)pp. 1-7 BioMed Central

Background Helicopter Emergency Medical Services (HEMS) are a scarce resource that can provide advanced emergency medical care to unwell or injured patients. Accurate tasking of HEMS is required to incidents where advanced pre-hospital clinical care is needed. We sought to evaluate any association between non-clinically trained dispatchers, following a bespoke algorithm, compared with HEMS paramedic dispatchers with respect to incidents requiring a critical HEMS intervention. Methods Retrospective analysis of prospectively collected data from two 12-month periods was performed (Period one: 1st April 2014 – 1st April 2015; Period two: 1st April 2016 – 1st April 2017). Period 1 was a Paramedic-led dispatch process. Period 2 was a non-clinical HEMS dispatcher assisted by a bespoke algorithm. Kent, Surrey & Sussex HEMS (KSS HEMS) is tasked to approximately 2500 cases annually and operates 24/7 across south-east England. The primary outcome measure was incidence of a HEMS intervention. Results A total of 4703 incidents were included; 2510 in period one and 2184 in period two. Variation in tasking was reduced by introducing non-clinical dispatchers. There was no difference in median time from 999 call to HEMS activation between period one and two (period one; median 7 min (IQR 4–17) vs period two; median 7 min (IQR 4–18). Non-clinical dispatch improved accuracy of HEMS tasking to a mission where a critical care intervention was required (OR 1.25, 95% CI 1.04–1.51, p = 0.02). Conclusion The introduction of non-clinical, HEMS-specific dispatch, aided by a bespoke algorithm improved accuracy of HEMS tasking. Further research is warranted to explore where this model could be effective in other HEMS services.

Richard Lyon, E de Sausmarez, Emily McWhirter, G Wareham, M Nelson, A Matthies, A Hudson, L Curtis, MQ Russell (2017)Pre-hospital transfusion of packed red blood cells in 147 patients from a UK helicopter emergency medical service, In: Scandinavian Journal of Trauma, Resuscitation and Emergency Medicine25(12) BioMed Central

Background: Early transfusion of packed red blood cells (PRBC) has been associated with improved survival in patients with haemorrhagic shock. This study aims to describe the characteristics of patients receiving pre-hospital blood transfusion and evaluate their subsequent need for in-hospital transfusion and surgery. Methods: The decision to administer a pre-hospital PRBC transfusion was based on clinical judgment. All patients transfused pre-hospital PRBC between February 2013 and December 2014 were included. Pre-hospital and in-hospital records were retrospectively reviewed. Results: One hundred forty-seven patients were included. 142 patients had traumatic injuries and 5 patients had haemorrhagic shock from a medical origin. Median Injury Severity Score was 30. 90% of patients receiving PRBC had an ISS of >15. Patients received a mean of 2.4(±1.1) units of PRBC in the pre-hospital phase. Median time from initial emergency call to hospital arrival was 114 min (IQR 103–140). There was significant improvement in systolic (p < 0.001), diastolic (p < 0.001) and mean arterial pressures (p < 0.001) with PRBC transfusion but there was no difference in HR (p = 0.961). Patients received PRBC significantly faster in the field than waiting until hospital arrival. At the receiving hospital 57% required an urgent surgical or interventional radiology procedure. At hospital arrival, patients had a mean lactate of 5.4(±4.4) mmol/L, pH of 6.9(±1.3) and base deficit of −8.1(±6.7). Mean initial serum adjusted calcium was 2.26(±0.29) mmol/L. 89% received further blood products in hospital. No transfusion complications or significant incidents occurred and 100% traceability was achieved. Discussion: Pre-hospital transfusion of packed red cells has the potential to improvde outcome for trauma patients with major haemorrhage. The pre-hospital time for trauma patients can be several hours, suggesting transfusion needs to start in the pre-hospital phase. Hospital transfusion research suggests a 1:1 ratio of packed red blood cells to plasma improves outcome and further research into pre-hospital adoption of this strategy is needed. Conclusion: Pre-hospital PRBC transfusion significantly reduces the time to transfusion for major trauma patients with suspected major haemorrhage. The majority of patients receiving pre-hospital PRBC were severely injured and required further transfusion in hospital. Further research is warranted to determine which patients are most likely to have outcome benefit from pre-hospital blood products and what triggers should be used for pre-hospital transfusion.

Joanna E. Oakeshott, Joanne E. Griggs, Gary M. Wareham, Richard Lyon (2018)Feasibility of prehospital freeze-dried plasma administration in a UK Helicopter Emergency Medical Service, In: European Journal of Emergency Medicine Lippincott, Williams & Wilkins

Background Early transfusion of patients with major traumatic haemorrhage may improve survival. This study aims to establish the feasibility of freeze-dried plasma transfusion in a Helicopter Emergency Medical Service in the United Kingdom. Method A retrospective observational study of major trauma patients attended by Kent, Surrey and Sussex Helicopter Emergency Medical Service and transfused freeze-dried plasma since it was introduced in April 2014. Results Of the 1873 patients attended over a 12-month period before its introduction, 79 patients received packed red blood cells (4.2%) with a total of 193 units transfused. Of 1881 patients after the introduction of freeze-dried plasma, 10 patients received packed red blood cells only and 66 received both packed red blood cells and freeze-dried plasma, with a total of 158 units of packed red blood cells transfused, representing an 18% reduction between the two 12-month periods. In the 20 months since its introduction, of 216 patients transfused with at least 1 unit of freeze-dried plasma, 116 (54.0%) patients received both freeze-dried plasma and packed red blood cells in a 1:1 ratio. Earlier transfusion was feasible, transferring the patient to hospital prior to transfusion would have incurred a delay of 71 minutes (IQR 59-90). Conclusion Pre-hospital freeze-dried plasma and packed red blood cell transfusion is feasible in a 1:1 ratio in patients with suspected traumatic haemorrhage. The use of freeze-dried plasma as a first line fluid bolus reduced the number of pre-hospital packed red blood cell units required and reduced the time to transfusion.

Ewoud ter Avest, Sam Taylor, Mark Wilson, Richard L Lyon (2020)Prehospital clinical signs are a poor predictor of raised intracranial pressure following traumatic brain injury, In: Emergency Medicine Journal BMJ Publishing Group

Background For the prehospital diagnosis of raised intracranial pressure (ICP), clinicians are reliant on clinical signs such as the Glasgow Coma Score (GCS), pupillary response and/or Cushing’s triad (hypertension, bradycardia and an irregular breathing pattern). This study aimed to explore the diagnostic accuracy of these signs as indicators of a raised ICP. Methods We performed a retrospective cohort study of adult patients attended by a Helicopter Emergency Medical Service (Air Ambulance Kent, Surrey Sussex), who had sustained a traumatic brain injury (TBI), requiring prehospital anaesthesia between 1 January 2016 and 1 January 2018. We established optimal cut-off values for clinical signs to identify patients with a raised ICP and investigated diagnostic accuracy for combinations of these values. Results Outcome data for 249 patients with TBI were available, of which 87 (35%) had a raised ICP. Optimal cut-off points for systolic blood pressure (SBP), heart rate (HR) and pupil diameter to discriminate patients with a raised ICP were, respectively, ˃160 mm Hg,˂60 bpm and ˃5 mm. Cushing criteria (SBP ˃160 mm Hg and HR ˂60 bpm) and pupillary response and size were complimentary in their ability to detect patients with a raised ICP. The presence of a fixed blown pupil or a Cushing’s response had a specificity of 93.2 (88.2–96.6)%, and a positive likelihood ratio (LR+) of 5.4 (2.9–10.2), whereas sensitivity and LR− were only 36.8 (26.7–47.8)% and 0.7 (0.6–0.8), respectively, (Area Under the Curve (AUC) 0.65 (0.57–0.73)). Sensitivity analysis revealed that optimal cut-off values and resultant accuracy were dependent on injury pattern. Conclusion Traditional clinical signs of raised ICP may under triage patients to prehospital treatment with hyperosmolar drugs. Further research should identify more accurate clinical signs or alternative non-invasive diagnostic aids in the prehospital environment.

Matthew Miller, Ilana Delroy-Buelles, Duncan Bootland, Richard Lyon (2019)A Spatial Analysis of Incident Location and Prehospital Mortality for Two United Kingdom Helicopter Emergency Medical Services (HEMS), In: Applied Spatial Analysis and Policypp. 1-16 Springer Nature

Most trauma and out of hospital cardiac arrest (OHCA) deaths occur prior to arrival at hospital, with increased risk for rural compared to urban patients. Essex and Hertfordshire Air Ambulance Trust (EHAAT) and Kent Surrey Sussex Air Ambulance Trust (KSS) provide a physician-paramedic Helicopter Emergency Medical Service (HEMS) in two regions of the United Kingdom. We investigated whether an association exists between prehospital mortality and distance from care in HEMS patients. We performed a retrospective study using spatial statistics to investigate the geographic distribution of scene outcome (alive versus deceased). We also performed multiple logistic regression of outcome against quartiles of distance from base to scene and a relative risk (RR) estimation over the operational areas. Organisations were analysed separately to assess consistency of spatial relationships. 2680 EHAAT and 4213 KSS patients met the inclusion criteria. Ripley’s K and Cross K functions indicated that outcomes (death and leaving the scene alive) cluster together. For KSS distance was not associated with outcome, for EHAAT distance was a significant predictor of mortality at furthest distance (41 to 95 km; OR 5.82, 95%CI 1.63 to 37.18, p = 0.019). Only one area of KSS and no areas of EHAAT had an increased RR of mortality. In contrast to previous research of pre-hospital patients, we found little evidence of geographic difference in scene outcome for trauma patients attended by the two HEMS services. Increased mortality risk for OHCA at the furthest distance from helicopter base was found in one organisation; a single area of increased RR of mortality was found for the other organisation.

Background Quality of manual cardiopulmonary resuscitation (CPR) during extrication and transport of out-of-hospital cardiac arrest victims is known to be poor. Performing manual CPR during ambulance transport poses significant risk to the attending emergency medical services crew. We sought to use pre-hospital video recording to objectively analyse the impact of introducing mechanical CPR with an extrication sheet (Autopulse, Zoll) to an advanced, second-tier cardiac arrest response team. Methods The study was conducted prospectively using defibrillator downloads and analysis of pre-hospital video recording to measure the quality of CPR during extrication from scene and ambulance transport of the OHCA patient. Adult patients with non-traumatic OHCA were included. The interruption to manual CPR to during extrication and to deploy the mechanical CPR device was analysed. Results In the manual CPR group, 53 OHCA cases were analysed for quality of CPR during extrication. The median time that chest compression was interrupted to allow the patient to be carried from scene to the ambulance was 270 s (IQR 201–387 s). 119 mechanical CPR cases were analysed. The median time interruption from last manual compression to first Autopulse compression was 39 s (IQR 29–47 s). The range from last manual compression to first Autopulse compression was 14–118 s. Conclusion Mechanical CPR used in combination with an extrication sheet can be effectively used to improve the quality of resuscitation during extrication and ambulance transport of the refractory OHCA patient. The time interval to deploy the mechanical CPR device can be shortened with regular simulation training.

Mark Durham, Pete Westhead, Richard Lyon, Margaret Lau-Walker, David Griffiths (2020)Prehospital neuromuscular blockade post OHCA: UK's first paramedic-delivered protocol, In: Journal of Paramedic Practice12(5)pp. 202-207 MA Healthcare

Background: Since 2016, critical care paramedics from the South East Coast Ambulance Service have offered neuromuscular blockade to patients for ventilatory/airway control after cardiac arrest. Aims: To examine the first cases of paramedic-delivered neuromuscular blockade, and evaluate the prevalence of its use and safety. Methods: Retrospective service evaluation of patients receiving post-arrest paralysis during the study period from 1 April 2016 until 31 July 2017. Findings: The study included 127 patients. The mean age of administration was 63 years, mean weight was 80 kg (SD: 19 kg), dose was 1 mg/kg and median time from rocuronium administration to hospital was 32 minutes (IQR 20–43 minutes). Three patients (2.3%) experienced a minor adverse incident. There were no major airway complications, nor other significant adverse incidents. Thirty-seven patients (31%) survived to discharge. Conclusion: From this patient group, paramedic-administered rocuronium in intubated patients who have experienced a cardiac arrest and a return of spontaneous circulation appears to be safe, but further interventional research is required to determine whether this improves patient outcomes.

C. Rose, E. ter Avest, R. M. Lyon (2023)Fatigue risk assessment of a Helicopter Emergency Medical Service crew working a 24/7 shift pattern: results of a prospective service evaluation, In: Scandinavian Journal of Trauma, Resuscitation and Emergency Medicine3172 BMC

Background The work of Helicopter Emergency Medical Services (HEMS) teams crosses the boundaries of several high-risk occupations including medicine, aviation, and transport. Working conditions can be challenging and operational demands requires a 24-h rota, resulting in disruption of the normal circadian rhythm. HEMS crews are therefore prone to both mental and physical fatigue. As fatigue in medical providers is linked to poor cognitive performance, degradation of psychomotor skills and error, this study aimed to explore the existence of predictable patterns of crew-fatigue in a HEMS service. Methods HEMS medical crew members working a 3-on 3-off forward rotating rota with a 5-week shift cycle were asked to do psychomotor vigilance tests (PVT) as an objective measure of fatigue. PVT testing was undertaken at the start, mid- and at the end of every shift during a full 5-week shift cycle. In addition, they were asked to score subjective tiredness with the Samn-Perelli Fatigue Scale (SPFS), and to keep a Transport Fatigue Assessment shift log, wherein they noted shift characteristics potentially related to fatigue. Primary outcome of interest was defined as the change in PVT and SPFS scores over time. Results Mean baseline resting PVT in milliseconds at the start of the study period was 427 [390–464]. There was an overall trend towards higher PVT-scores with shift progression mean [95% CI] PVT at the start of shifts 447 [433–460]; halfway through the shift 452 [440–463]; end of the shift 459 [444–475], p = 0.10), whereas SPFS scores remained constant. Within a 5 week forward-rotating cycle, an overall trend towards a gradual increase in both average PVT (from 436 [238–454] to 460 [371–527, p = 0.68] ms;) and SPFS (from 2.9 [2.6–3.2] to 3.6 [3.1–4.0], p = 0.38) was observed, although significant interindividual variation was present. Reported SPFS scores ≥ 4 (moderate fatigue) were mainly related to workload (number of jobs) and transport mode (car-based shifts). Conclusion An overall trend towards a decline in psychomotor vigilance and an increase in self-reported tiredness was found for HEMS crew over a 5-week shift cycle. Using a bespoke predictive fatigue tool on a day-to-day basis could increase fatigue awareness and provide a framework to which relevant mitigating options can be applied.

E. ter Avest, E. Lambert, R. de Coverly, H. Tucker, J. Griggs, M. H. Wilson, A. Ghorbangholi, J. Williams, R.M. Lyon (2019)Live video footage from scene to aid helicopter emergency medical service dispatch: a feasibility study, In: Scandinavian Journal of Trauma, Resuscitation and Emergency Medicine2755 BMC

Background Obtaining accurate information from a 112 caller is key to correct tasking of Helicopter Emergency Medical Services (HEMS). Being able to view the incident scene via video from a mobile phone may assist HEMS dispatch by providing more accurate information such as mechanism of injury and/or injuries sustained. The objective of this study is to describe the acceptability and feasibility of using live video footage from the mobile phone of a 112 caller as an HEMS dispatch aid. Methods Live footage is obtained via the 112 caller’s mobile phone camera through the secure GoodSAM app’s Instant-on-scene™ platform. Video footage is streamed directly to the dispatcher, and not stored. During the feasibility trial period, dispatchers noted the purpose for which they used the footage and rated ease of use and any technical- and operational issues they encountered. A subjective assessment of caller acceptance to use video was conducted. Results Video footage from scene was attempted for 21 emergency calls. The leading reasons listed by the dispatchers to use live footage were to directly assess the patient (18/21) and to obtain information about the mechanism of injury and the scene (11/21). HEMS dispatchers rated the ease of use with a 4.95 on a 5-point scale (range 4–5). All callers gave permission to stream from their telephone camera. Video footage from scene was successfully obtained in 19 calls, and was used by the dispatcher as an aid to send (5) or stand down (14) a Helicopter Emergency Medical Services team. Conclusion Live video footage from a 112 caller can be used to provide dispatchers with more information from the scene of an incident and the clinical condition of the patient(s). The use of mobile phone video was readily accepted by the 112 caller and the technology robust. Further research is warranted to assess the impact video from scene could have on HEMS dispatching.

Introduction Major trauma can result in both life-threatening haemorrhage and traumatic brain injury (TBI). The pre-hospital management of these conditions, particularly in relation to the cardiovascular system, is very different. TBI can result in cardiovascular instability but the exact incidence remains poorly described. This study explores the incidence of cardiovascular instability in patients undergoing pre-hospital anaesthesia for suspected TBI. Methods Retrospective case series of all pre-hospital trauma patients attended by Kent, Surrey & Sussex Air Ambulance Trust (United Kingdom) trauma team during the period 1 January 2015–31 December 2016. Patients were included if they showed clinical signs of TBI, underwent pre-hospital anaesthesia and hospital computed tomography scanning subsequently confirmed an isolated TBI. Results Out of 121 patients with confirmed isolated TBI, 68 were cardiovascularly stable throughout the pre-anaesthesia phase, whilst 53 (44%) showed signs of instability (HR ˃ 100bpm and/or SBP ˂ 100 mmHg pre-anaesthesia). Hypotension (SBP ˂ 100) with or without tachycardia was present in 14 (12%) patients. 10 (8%) patients with isolated TBI received pre-hospital blood product transfusion. Conclusion Increased awareness that traumatic brain injury can cause significant derangement to heart rate and blood pressure, even in the absence of major haemorrhage, would allow the pre-hospital clinician to treat cardiovascular instability with the most appropriate means, such as crystalloid and vasopressors, to limit secondary brain injury.

GA Sunde, J-K Heltne, D Lockey, B Burns, M Sandberg, K Fredriksen, KO Hufthammer, A Soti, R Lyon, H Jantti, A Kamarainen, BO Reid, T Silfvast, F Harm, SJM Sollid (2015)Airway management by physician-staffed Helicopter Emergency Medical Services - a prospective, multicentre, observational study of 2,327 patients, In: SCANDINAVIAN JOURNAL OF TRAUMA RESUSCITATION & EMERGENCY MEDICINE23ARTN 57 BIOMED CENTRAL LTD