Prehospital Management of Penetrating Neck Injuries: An Evaluation of Practice.

OBJECTIVE: Penetrating neck injuries (PNIs) can occur at multiple anatomic sites and involve airway, nerve, vascular, and gastrointestinal structures. They pose a unique challenge to clinicians, especially in the prehospital setting. Published guidance on the prehospital management of PNIs is limited, and there is no review of the current prehospital practice. METHODS: A retrospective electronic case note review of PNIs managed within 1 UK helicopter emergency medical service (HEMS) over a 7-year period was undertaken. Data were collected on the zone of injury, mechanism of injury, prehospital times, patient demographics, prehospital interventions, and on-scene mortality. RESULTS: Ninety-eight patients met the study inclusion criteria, 40% of whom had zone 2 neck injuries. Eighty-three percent were male with a mean age of 42 years. The predominant injury mechanism was interpersonal violence (51%) followed by self-harm (47%). Fifteen percent underwent prehospital emergency anesthesia, 17% underwent prehospital blood transfusion, and 30% had a hemostatic dressing applied. No patients underwent cervical spine immobilization. One percent underwent resuscitative thoracotomy. Five percent 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 the hospital. Airway and hemorrhagic pathologies must be managed, often concomitantly. Targeted injury prevention to reduce interpersonal violence must ensue. The author group intends to devise a national Delphi and derive consensus guidelines for the management of prehospital PNIs.

A comparison between sudden cardiac arrest on military bases and non-military settings.

INTRODUCTION: Out-of-hospital cardiac arrests contribute to significant morbidity and mortality in both non-military/civilian and military populations. Early CPR and AED use have been linked with improved outcomes. There is public health interest in identifying communities with high rates of both with the hopes of creating generalizable tactics for improving cardiac arrest survival. METHODS: We examined a national registry of EMS activations in the United States (NEMSIS). Inclusion criteria were witnessed cardiac arrests from January 2020 to September 2022 where EMS providers documented the location of the arrest, whether CPR was provided prior to their arrival (yes/no), and whether an AED was applied prior to their arrival (yes/no). Cardiac arrests were then classified as occurring on a military base or in a non-military setting. RESULTS: A total of 60 witnessed cardiac arrests on military bases and 202,605 witnessed cardiac arrests in non-military settings met inclusion criteria. Importantly, the prevalence of CPR and AED use prior to EMS arrival was significantly higher on military bases compared to non-military settings. CONCLUSIONS: Reasons for the trends we observed may be a greater availability of CPR-trained individuals and AEDs on military bases, as well as a widespread willingness to provide aid to victims of cardiac arrest. Further research should examine cardiac arrests on military bases.

Mechanical Cardiopulmonary Resuscitation's Role in Helicopter Air Ambulances: A Narrative Review.

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.

Feasibility of Prehospital Emergency Anesthesia in the Cabin of an AW169 Helicopter Wearing Personal Protective Equipment During Coronavirus Disease 2019.

OBJECTIVE: Prehospital emergency anesthesia in the form of rapid sequence intubation (RSI) is a critical intervention delivered by advanced prehospital 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 (AGPs) for in-aircraft, on-the-ground RSI. METHODS: Air Ambulance Kent Surrey Sussex is a helicopter emergency medical service that uses an AW169 cabin simulator. Wearing full AGP PPE (eye protection, FFP3 mask, gown, and 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. Prespecified 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. The time to completed endotracheal intubation (ETI) was fastest (287 seconds) in the standard scenario and slower (370 seconds, P = .01) in the CICO scenario. The 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 were also reported. CONCLUSION: In-aircraft RSI (aircraft on the ground) while wearing PPE for AGPs had no significant impact on the time to successful completion of ETI in a simulated setting. Patient safety is paramount in civilian helicopter emergency medical services, but the adoption of in-aircraft RSI could confer significant patient benefit in terms of prehospital time savings, and further research is warranted.

Prehospital critical care is associated with increased survival in adult trauma patients in Scotland.

BACKGROUND: Scotland has three prehospital critical care teams (PHCCTs) providing enhanced care support to a usually paramedic-delivered ambulance service. The effect of the PHCCTs on patient survival following trauma in Scotland is not currently known nationally. METHODS: National registry-based retrospective cohort study using 2011-2016 data from the Scottish Trauma Audit Group. 30-day mortality was compared between groups after multivariate analysis to account for confounding variables. RESULTS: Our data set comprised 17 157 patients, with a mean age of 54.7 years and 8206 (57.5%) of male gender. 2877 patients in the registry were excluded due to incomplete data on their level of prehospital care, leaving an eligible group of 14 280. 13 504 injured adults who received care from ambulance clinicians (paramedics or technicians) were compared with 776 whose care included input from a PHCCT. The median Injury Severity Score (ISS) across all eligible patients was 9; 3076 patients (21.5%) met the ISS>15 criterion for major trauma. Patients in the PHCCT cohort were statistically significantly (all p<0.01) more likely to be male; be transported to a prospective Major Trauma Centre; have suffered major trauma; have suffered a severe head injury; be transported by air and be intubated prior to arrival in hospital. Following multivariate analysis, the OR for 30-day mortality for patients seen by a PHCCT was 0.56 (95% CI 0.36 to 0.86, p=0.01). CONCLUSION: Prehospital care provided by a physician-led critical care team was associated with an increased chance of survival at 30 days when compared with care provided by ambulance clinicians.

Feasibility of Prehospital Rapid Sequence Intubation in the Cabin of an AW169 Helicopter.

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.

Prehospital Death After Traumatic Cardiac Arrest: Time for Better Feedback?

OBJECTIVE: The aim of this study was to establish if in patients who die at scene as a result of 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 Air Ambulance Kent, Surrey and Sussex between January 1, 2015, and June 30, 2016. RESULTS: In total, 159 patients were attended to during the study period. Postmortem reports could not be obtained for 37 patients, mainly because of unestablished identities at the scene. Forty of the 122 reports obtained were full postmortem 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 postmortem report, injuries were identified during the postmortem examination that had not been noted on scene. CONCLUSION: Feedback from coroners to prehospital teams after patients die as a result of TCA is important but currently suboptimal.

The Impact of Helicopter Emergency Medical Service Night Operations in South East England.

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.

Significant modification of traditional rapid sequence induction improves safety and effectiveness of pre-hospital trauma anaesthesia.

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.

The Need for a UK Helicopter Emergency Medical Service by Night: A Prospective, Simulation Study.

BACKGROUND: 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. METHODS: 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. RESULTS: 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. CONCLUSION: 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.

A specialist, second-tier response to out-of-hospital cardiac arrest: setting up TOPCAT2.

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.

The SEE-IT Trial: emergency medical services Streaming Enabled Evaluation In Trauma: a feasibility randomised controlled trial.

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: ISRCTN 11449333 (22 March 2022). https://www.isrctn.com/ISRCTN11449333.

Tissue oxygen saturation measurement in prehospital trauma patients: a pilot, feasibility study.

BACKGROUND: This study evaluated the feasibility of prehospital tissue oxygen saturation (StO2) in major trauma patients. METHODS: A prospective, pilot feasibility study carried out in a physician based prehospital trauma service. RESULTS: Prehospital StO2 was recorded on 13 patients. Continuous StO2 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 StO2 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 StO2 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.

The Swiss bus accident on 13 March 2012: lessons for pre-hospital care.

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.

Early goal-directed therapy: can the emergency department deliver?

BACKGROUND: Early 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. OBJECTIVE: To establish the level of awareness and skills necessary for EGDT to be implemented by emergency medicine (EM) specialist registrars (SpR) working in Scottish EDs. METHOD: A cross-sectional web-based survey of all 49 Scottish EM SpRs was performed. RESULTS: 42 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. CONCLUSION: Full 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.

Issues around conducting prehospital research on out-of-hospital cardiac arrest: lessons from the TOPCAT study.

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.

Field intubation of cardiac arrest patients: a dying art?

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.

Diagnostic performance of prehospital ultrasound diagnosis for traumatic pneumothorax by a UK Helicopter Emergency Medical Service.

OBJECTIVE: Up to 20% of major trauma patients may sustain a pneumothorax. Traumatic pneumothoraces can be difficult to diagnose on scene. Although the use of handheld ultrasound (HHUS) is becoming increasingly widespread, there remains uncertainty about its efficacy as a diagnostic tool in the prehospital setting. The aim of this study was to determine the diagnostic performance of prehospital chest HHUS in trauma patients. METHOD: Retrospective review of trauma patients who received a prehospital chest HHUS and subsequently conveyed to the Royal Sussex County Hospital (RSCH) between 1 July 2013 and 24 September 2018. Data including patient age, sex, mechanism of injury and clinical interventions were obtained. Prehospital ultrasound findings were compared with the computer tomography (CT) scan performed on arrival at the hospital. RESULTS: Four hundred eleven patients were conveyed to RSCH, the single largest group being following road traffic collisions. The majority of HHUS (66%) were performed by doctors. Three hundred sixty-one patients (88%) subsequently had a CT scan. Of these, 98 patients (27%) were found to have pneumothoraces. For pneumothorax diagnosis, prehospital HHUS had a sensitivity of 28% [95% confidence interval (CI): 19-37%] and specificity of 98% [95% CI: 97-99%]. CONCLUSION: In this retrospective study, sensitivity of prehospital HHUS for diagnosing a pneumothorax was lower than is often reported in in-hospital studies. This suggests that caution should be exercised in using HHUS for the exclusion of pneumothorax in the prehospital setting.

Feasibility of prehospital freeze-dried plasma administration in a UK Helicopter Emergency Medical Service.

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 UK. PATIENTS AND METHODS: 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 one 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 the hospital before transfusion would have incurred a delay of 71 min (interquartile range: 59-90 min). CONCLUSION: Prehospital 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 prehospital packed red blood cell units required and reduced the time to transfusion.