Air ambulance tasking: mechanism of injury, telephone interrogation or ambulance crew assessment?

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.

Understanding patient non-transport decision theories in the pre-hospital setting: a narrative review

BACKGROUND

In pre-hospital emergency care, decisions regarding patient non-conveyance emerged as significant determinants of healthcare outcomes and resource utilization. These complex decisions became integral to the progress of emergency medical services, thus warranting an evolving exploration within the medical discourse.

OBJECTIVES AND METHODS

This narrative review aimed to synthesize and critically evaluate various theoretical stances on patient non-conveyance in the pre-hospital emergency. The focus on studies published between January 2012 and August 2022 was intentional to capture contemporary practices and insights. PubMed and Google Scholar served as the primary databases for the investigation, while the AL-Rayyan® software facilitated a thorough screening process.

RESULTS AND DISCUSSION

Twenty-nine studies-encompassing articles, books, and theses-were discovered through our search, each presenting unique perspectives on patient non-transport, thus highlighting its criticality as a healthcare concern. Predominant factors influencing non-transport decisions were classified into patient-initiated refusals (PIR), clinician-initiated decisions (CID), and dispatcher-initiated decisions (DID).

CONCLUSIONS

The issue of patient non-conveyance to hospitals continues to pose a crucial challenge to the seamless operation of emergency healthcare systems, warranting increased attention from various healthcare entities. To comprehend and pinpoint potential areas of improvement, a comprehensive analysis of pre-hospital non-transport events is imperative. A well-informed, strategic approach could prevent resource waste while ensuring patients receive the required and definitive care.

KEY MESSAGES

Why is this topic important? Some studies have suggested that non-transport to hospitals following emergency calls is safe. However, it is a concerning issue for health systems. It is also considered a key performance metric for health systems. What does this review attempt to show? This review aimed to map the various factors discussed in the literature regarding the decisions not to transport patients following emergency calls in a pre-hospital setting. What are the key findings? The existing theories regarding non-transport to hospitals after the provision of emergency care in the pre-hospital setting were identified. Non-transport due to non-clinical decisions jeopardizes emergency care outcomes for paediatric and elderly patients in particular. Hence, further research is required to identify and control the factors governing these decisions. How is patient care impacted? The decisions regarding patient transport following emergency calls in a pre-hospital setting are crucial for patient outcomes. They could impact the pre-hospital emergency care outcomes as well as patient safety. They can also affect the emergency services resources' ability to respond to other critical emergencies.

Nine golden codes: improving the accuracy of Helicopter Emergency Medical Services (HEMS) dispatch-a retrospective, multi-organisational study in the East of England

BACKGROUND

Helicopter Emergency Medical Services (HEMS) are a limited and expensive resource, and should be intelligently tasked. HEMS dispatch was identified as a key research priority in 2011, with a call to identify a 'general set of criteria with the highest discriminating potential'. However, there have been no published data analyses in the past decade that specifically address this priority, and this priority has been reaffirmed in 2023. The objective of this study was to define the dispatch criteria available at the time of the initial emergency call with the greatest HEMS utility using a large, regional, multi-organizational dataset in the UK.

METHODS

This retrospective observational study utilized dispatch data from a regional emergency medical service (EMS) and three HEMS organisations in the East of England, 2016-2019. In a logistic regression model, Advanced Medical Priority Dispatch System (AMPDS) codes with ≥ 50 HEMS dispatches in the study period were compared with the remainder to identify codes with high-levels of HEMS patient contact and HEMS-level intervention/drug/diagnostic (HLIDD). The primary outcome was to identify AMPDS codes with a > 10% HEMS dispatch rate of all EMS taskings that would result in 10-20 high-utility HEMS dispatches per 24-h period in the East of England. Data were analysed in R, and are reported as number (percentage); significance was p < 0.05.

RESULTS

There were n = 25,491 HEMS dispatches (6400 per year), of which n = 23,030 (90.3%) had an associated AMPDS code. n = 13,778 (59.8%) of HEMS dispatches resulted in patient contact, and n = 8437 (36.6%) had an HLIDD. 43 AMPDS codes had significantly greater rates of patient contact and/or HLIDD compared to the reference group. In an exploratory analysis, a cut-off of ≥ 70% patient contact rate and/or ≥ 70% HLIDD (with a > 10% HEMS dispatch of all EMS taskings) resulted in 17 taskings per 24-h period. This definition derived nine AMPDS codes with high HEMS utility.

CONCLUSION

We have identified nine 'golden' AMPDS codes, available at the time of initial emergency call, that are associated with high-levels of whole-system and HEMS utility in the East of England. We propose that UK EMS should consider immediate HEMS dispatch to these codes.

The SEE-IT Trial: emergency medical services treaming nabled valuation n rauma: study protocol for an interventional feasibility randomised controlled trial

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 ANALYSIS

The 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 DISSEMINATION

The 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 NUMBER

ISRCTN11449333.

Looking back to inform the future: a review of published paramedicine research

OBJECTIVE

Paramedicine has evolved in ways that may outpace the science informing these changes. Examining the scholarly pursuits of paramedicine may provide insights into the historical academic focus, which may inform future endeavors and evolution of paramedicine. The objective of this study was to explore the existing discourse in paramedicine research to reflect on the academic pursuits of this community.

METHODS

We searched Medline, Embase, CINAHL, Google Scholar and Web of Science from January, 2006 to April, 2019. We further refined the yield using a ranking formula that prioritized journals most relevant to paramedicine, then sampled randomly in two-year clusters for full text review. We extracted literature type, study topic and context, then used elements of qualitative content, thematic, and discourse analysis to further describe the sample.

RESULTS

The initial search yielded 99,124 citations, leaving 54,638 after removing duplicates and 7084 relevant articles from nine journals after ranking. Subsequently, 2058 articles were included for topic categorization, and 241 papers were included for full text analysis after random sampling. Overall, this literature reveals: 1) a relatively narrow topic focus, given the majority of research has concentrated on general operational activities and specific clinical conditions and interventions (e.g., resuscitation, airway management, etc.); 2) a limited methodological (and possibly philosophical) focus, given that most were observational studies (e.g., cohort, case control, and case series) or editorial/commentary; 3) a variety of observed trajectories of academic attention, indicating where the evolution of paramedicine is evident, areas where scope of practice is uncertain, and areas that aim to improve skills historically considered core to paramedic clinical practice.

CONCLUSIONS

Included articles suggest a relatively narrow topic focus, a limited methodological focus, and observed trajectories of academic attention indicating where research pursuits and priorities are shifting. We have highlighted that the academic focus may require an alignment with aspirational and direction setting documents aimed at developing paramedicine. This review may be a snapshot of scholarly activity that reflects a young medically directed profession and systems focusing on a few high acuity conditions, with aspirations of professional autonomy contributing to the health and social well-being of communities.

Optimizing an Emergency Medical Dispatch System to Improve Prehospital Diagnosis and Treatment of Acute Coronary Syndrome: Nationwide Retrospective Study in China

Background

Acute coronary syndrome (ACS) is the most time-sensitive acute cardiac event that requires rapid dispatching and response. The medical priority dispatch system (MPDS), one of the most extensively used types of emergency dispatch systems, is hypothesized to provide better-quality prehospital emergency treatment. However, few studies have revealed the impact of MPDS use on the process of ACS care.

Objective

This study aimed to investigate whether the use of MPDS was associated with higher prehospital diagnosis accuracy and shorter prehospital delay for patients with ACS transferred by an emergency medical service (EMS), using a national database in China.

Methods

This retrospective analysis was based on an integrated database of China’s MPDS and hospital registry. From January 1, 2016, to December 31, 2020, EMS-treated ACS cases were divided into before MPDS and after MPDS groups in accordance with the MPDS launch time at each EMS center. The primary outcomes included diagnosis consistency between hospital admission and discharge, and prehospital delay. Multivariable logistic regression and propensity score–matching analysis were performed to compare outcomes between the 2 groups for total ACS and subtypes.

Results

A total of 9806 ACS cases (3561 before MPDS and 6245 after MPDS) treated by 43 EMS centers were included. The overall diagnosis consistency of the after MPDS group (Cohen κ=0.918, P<.001) was higher than that of the before MPDS group (Cohen κ=0.889, P<.001). After the use of the MPDS, the call-to-EMS arrival time was shortened in the matched ACS cases (20.0 vs 16.0 min, P<.001; adjusted difference: –1.67, 95% CI –2.33 to –1.02; P<.001) and in the subtype of ST-elevation myocardial infarction (adjusted difference: –3.81, 95% CI –4.63 to –2.98, P<.001), while the EMS arrival-to-door time (20.0 vs 20.0 min, P=.31) was not significantly different in all ACS cases and subtypes.

Conclusions

The optimized use of MPDS in China was associated with increased diagnosis consistency and a reduced call-to-EMS arrival time among EMS-treated patients with ACS. An emergency medical dispatch system should be designed specifically to fit into different prehospital modes in the EMS system on a regional basis.

A Framework for Case-Based Learning in Prehospital Medicine: The London's Air Ambulance Experience

Clinical governance is the framework around which health care organizations can maintain a higher standard of safety and care. One of the central aspects of clinical governance is continuous professional education, including case-based review and case-based learning. In this article, we present the case-based education process in use at London's Air Ambulance, a mature advanced prehospital system in London, UK. The case review process begins with an on-scene hot debrief, an informal process often involving other emergency services. This is usually followed by internal team feedback and debrief and patient follow-up. All cases are then reviewed over the next 24 to 48 hours by the duty prehospital consultant (attending) in the rapid review process. After this, certain cases are volunteered or selected for discussion in the twice weekly death and disability (D&D) meeting or the monthly dispatch meeting. A small subset of cases is highlighted through this process for full formal audit and presentation at the monthly clinical governance meetings based on their educational value. Another subset of cases involving a fatality is also discussed at the monthly clinical pathology correlation meeting with the input of local forensic pathologists. Organization of the process, structure of the meetings, and educational value are described in detail.

Machine Learning-Based Text Analysis to Predict Severely Injured Patients in Emergency Medical Dispatch: Model Development and Validation

Background

Early recognition of severely injured patients in prehospital settings is of paramount importance for timely treatment and transportation of patients to further treatment facilities. The dispatching accuracy has seldom been addressed in previous studies.

Objective

In this study, we aimed to build a machine learning–based model through text mining of emergency calls for the automated identification of severely injured patients after a road accident.

Methods

Audio recordings of road accidents in Taipei City, Taiwan, in 2018 were obtained and randomly sampled. Data on call transfers or non-Mandarin speeches were excluded. To predict cases of severe trauma identified on-site by emergency medical technicians, all included cases were evaluated by both humans (6 dispatchers) and a machine learning model, that is, a prehospital-activated major trauma (PAMT) model. The PAMT model was developed using term frequency–inverse document frequency, rule-based classification, and a Bernoulli naïve Bayes classifier. Repeated random subsampling cross-validation was applied to evaluate the robustness of the model. The prediction performance of dispatchers and the PAMT model, in severe cases, was compared. Performance was indicated by sensitivity, specificity, positive predictive value, negative predictive value, and accuracy.

Results

Although the mean sensitivity and negative predictive value obtained by the PAMT model were higher than those of dispatchers, they obtained higher mean specificity, positive predictive value, and accuracy. The mean accuracy of the PAMT model, from certainty level 0 (lowest certainty) to level 6 (highest certainty), was higher except for levels 5 and 6. The overall performances of the dispatchers and the PAMT model were similar; however, the PAMT model had higher accuracy in cases where the dispatchers were less certain of their judgments.

Conclusions

A machine learning–based model, called the PAMT model, was developed to predict severe road accident trauma. The results of our study suggest that the accuracy of the PAMT model is not superior to that of the participating dispatchers; however, it may assist dispatchers when they lack confidence while making a judgment.

Improving ambulance dispatch triage to trauma: A scoping review using the framework of development and evaluation of clinical prediction rules

OBJECTIVE

Ambulance dispatch algorithms should function as clinical prediction rules, identifying high acuity patients for advanced life support, and low acuity patients for non-urgent transport. Systematic reviews of dispatch algorithms are rare and focus on study types specific to the final phases of rule development, such as impact studies, and may miss the complete value-added evidence chain. We sought to summarise the literature for studies seeking to improve dispatch in trauma by performing a scoping review according to standard frameworks for developing and evaluating clinical prediction rules.

METHODS

We performed a scoping review searching MEDLINE, EMBASE, CINAHL, the CENTRAL trials registry, and grey literature from January 2005 to October 2021. We included all study types investigating dispatch triage to injured patients in the English language. We reported the clinical prediction rule phase (derivation, validation, impact analysis, or user acceptance) and the performance and outcomes measured for high and low acuity trauma patients.

RESULTS

Of 2067 papers screened, we identified 12 low and 30 high acuity studies. Derivation studies were most common (52%) and rule-based computer-aided dispatch was the most frequently investigated (23 studies). Impact studies rarely reported a prior validation phase, and few validation studies had their impact investigated. Common outcome measures in each phase were infrequent (0 to 27%), making a comparison between protocols difficult. A series of papers for low acuity patients and another for pediatric trauma followed clinical prediction rule development. Some low acuity Medical Priority Dispatch System codes are associated with the infrequent requirement for advanced life support and clinician review of computer-aided dispatch may enhance dispatch triage accuracy in studies of helicopter emergency medical services.

CONCLUSIONS

Few derivation and validation studies were followed by an impact study, indicating important gaps in the value-added evidence chain. While impact studies suggest clinician oversight may enhance dispatch, the opportunity exists to standardize outcomes, identify trauma-specific low acuity codes, and develop intelligent dispatch systems.

Improving the Appropriateness of Advanced Life Support Teams' Dispatch: A Before-After Study

BACKGROUND AND IMPORTANCE

The dispatch of Advanced Life Support (ALS) teams in Emergency Medical Services (EMS) is still a hardly studied aspect of prehospital emergency logistics. In 2015, the dispatch algorithm of Emilia Est Emergency Operation Centre (EE-EOC) was implemented and the dispatch of ALS teams was changed from primary to secondary based on triage of dispatched vehicles for high-priority interventions when teams with Immediate Life Support (ILS) skills were dispatched.

OBJECTIVES

This study aimed to evaluate the effects on the appropriateness of ALS teams' intervention and their employment time, and to compare sensitivity and specificity of the algorithm implementation.

DESIGN

This was a retrospective before-after observational study.

SETTINGS AND PARTICIPANTS

Primary dispatches managed by EE-EOC involving ambulances and/or ALS teams were included. Two groups were created on the basis of the years of intervention (2013-2014 versus 2017-2018).

INTERVENTION

A switch from primary to secondary dispatch of ALS teams in case of high-priority dispatches managed by ILS teams was implemented.

OUTCOMES

Appropriateness of ALS team intervention, total task time of ALS vehicles, and sensitivity and specificity of the algorithm were reviewed.

RESULTS

The study included 242,501 emergency calls that generated 56,567 red code dispatches. The new algorithm significantly increased global sensitivity and specificity of the system in terms of recognition of potential need of ALS intervention and the specificity of primary ALS dispatch. The appropriateness of ALS intervention was significantly increased; total tasking time per day for ALS and the number of critical dispatches without ALS available were reduced.

CONCLUSION

The revision of the dispatch criteria and the extension of the two-tiered dispatch for ALS teams significantly increased the appropriateness of ALS intervention and reduced both the global tasking time and the number of high-priority dispatches without ALS teams available.

The first seven years of nationally organized helicopter emergency medical services in Finland - the data from quality registry

Background

Helicopter Emergency Medical Services (HEMS) play an important role in prehospital care of the critically ill. Differences in funding, crew composition, dispatch criteria and mission profile make comparison between systems challenging. Several systems incorporate databases for quality control, performance evaluation and scientific purposes. FinnHEMS database was incorporated for such purposes following the national organization of HEMS in Finland 2012. The aims of this study are to describe information recorded in the database, data collection, and operational characteristics of Finnish HEMS during 2012–2018.

Methods

All dispatches of the six Finnish HEMS units recorded in the national database from 2012 to 2018 were included in this observational registry study. Five of the units are physician staffed, and all are on call 24/7. The database follows a template for uniform reporting in physician staffed pre-hospital services, exceeding the recommended variables of relevant guidelines.

Results

The study included 100,482 dispatches, resulting in 33,844 (34%) patient contacts. Variables were recorded with little or no missing data. A total of 16,045 patients (16%) were escorted by HEMS to hospital, of which 2239 (2%) by helicopter. Of encountered patients 4195 (4%) were declared deceased on scene. The number of denied or cancelled dispatches was 66,638 (66%). The majority of patients were male (21,185, 63%), and the median age was 57.7 years. The median American Society of Anesthesiologists Physical Scale classification was 2 and Eastern Cooperative Oncology Group performance class 0. The most common reason for response was trauma representing 26% (8897) of the patients, followed by out-of-hospital cardiac arrest 20% (6900), acute neurological reason excluding stroke 13% (4366) and intoxication and related psychiatric conditions 10% (3318). Blunt trauma (86%, 7653) predominated in the trauma classification.

Conclusions

Gathering detailed and comprehensive data nationally on all HEMS missions is feasible. A national database provides valuable insights into where the operation of HEMS could be improved. We observed a high number of cancelled or denied missions and a low percentage of patients transported by helicopter. The medical problem of encountered patients also differs from comparable systems.

Epidemiology and location of primary retrieval missions in a Scottish aeromedical service

INTRODUCTION

Prehospital critical care teams comprising an appropriately trained physician and paramedic or nurse have been associated with improved outcomes in selected trauma patients. These teams are a scarce and expensive resource, especially when delivered by rotary air assets. The optimal tasking of prehospital critical care teams is therefore vital and remains a subject of debate. Emergency Medical Retrieval Service (EMRS) provides a prehospital critical care response team to incidents over a large area of Scotland either by air or by road.

METHODS

A convenience sample of consecutive EMRS missions covering a period of 18 months from May 2013 to January 2015 was taken. These missions were matched with the ambulance service information on geographical location of the incident. In order to assess the appropriateness of tasking, interventions undertaken on each mission were analysed and divided into two subcategories: 'critical care interventions' and 'advanced medical interventions'. A tasking was deemed appropriate if it included either category of intervention or if a patient was pronounced life extinct at the scene.

RESULTS

A total of 1279 primary missions were undertaken during the study period. Of these, 493 primary missions met the inclusion criteria and generated complete location data. The median distance to scene was calculated as 5.6 miles for land responses and 34.2 miles for air responses. Overall, critical care interventions were performed on 17% (84/493) of patients. A further 21% (102/493) of patients had an advanced medical intervention. Including those patients for whom life was pronounced extinct on scene by the EMRS team, a total of 42% (206/493) taskings were appropriate.

DISCUSSION

Overall, our data show a wide geographical spread of tasking for our service, which is in keeping with other suburban/rural models of prehospital care. Tasking accuracy is also comparable to the accuracy shown by other similar services.

Live video footage from scene to aid helicopter emergency medical service dispatch: a feasibility study

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.

The accuracy of medical dispatch - a systematic review

BACKGROUND

It is a challenge to dispatch Emergency medical Services (EMS) appropriately with limited resources and maintaining patient safety; this requires accurate dispatching systems. The objective of the current systematic review was to examine the evidence, according to GRADE, for medical dispatching systems to accurately dispatch EMS according to level of acuity and in recognition of specific conditions. A systematic search was performed trough PubMed, Web of Science, Embase (free text in all fields), Centre for Reviews and Dissemination (CRD), and Cochrane Central Register of Controlled Trials up to 16th of May, 2017. A combination of keywords and Medical Subject Heading (MeSH) terms relevant to "emergency medical dispatch criteria" were used, to search for articles published between 2012 and 2017. Publications were included according to the inclusion/exclusion criteria using the Systematic Reviews and Meta-Analyses (PRISMA) protocol. Level of evidence was evaluated in accordance with Grading of Recommendations Assessment, Development and Evaluation (GRADE). Articles included were those that provided evidence for at least one of the measures of dispatch system accuracy; i.e. sensitivity, specificity, positive and negative predictive and/or over- and under-triage. The search identified 1445 articles. After the removal of duplicates, 382 titles were reviewed for relevance and an additional 359 articles were excluded based on manuscript title and abstract. An additional five articles were excluded after review of the full text versions of the remaining articles. The current review included 18 publications which all were based on primary research.

CONCLUSIONS

The 18 articles addressed the identification of cardiac arrest, stroke, medical priority and major trauma using different dispatching systems. The results of the current review show that there is a very low to low overall level of evidence for the accuracy of medical dispatching systems. We suggest that it is necessary to create a consensus on common standards for reporting before consensus can be reached for the level of accuracy in medical dispatching systems.

A novel method of non-clinical dispatch is associated with a higher rate of critical Helicopter Emergency Medical Service intervention

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.

Critcomms: a national cross-sectional questionnaire based study to investigate prehospital handover practices between ambulance clinicians and specialist prehospital teams in Scotland

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.

Clinician tasking in ambulance control improves the identification of major trauma patients and pre-hospital critical care team tasking

INTRODUCTION

Trauma remains the fourth leading cause of death in western countries and is the leading cause of death in the first four decades of life. NICE guidance in 2016 advocated the attendance of pre-hospital critical care trauma team (PHCCT) in the pre-hospital stage of the care of patients with major trauma. Previous publications support dispatch by clinicians who are also actively involved in the delivery of the PHCCT service; however there is a lack of objective outcome measures across the current reviewed evidence base. In this study, we aimed to assess the accuracy of PHCCT clinician led dispatch, when measured by Injury Severity Score (ISS).

METHODS

A retrospective cohort study over a 2 year period pre and post implementation of a PHCCT clinician led dispatch of PHCCT for potential major trauma patients, using national ambulance data combined with national trauma registry data.

RESULTS

A total of 99,702 trauma related calls were made to SAS including 495 major trauma patients with an ISS >15, and a total of 454 dispatches of a PHCCT. Following the introduction of a PHCCT clinician staffed trauma desk, the sensitivity for major trauma was increased from 11.3% to 25.9%. The difference in sensitivity between the pre and post trauma desk group was significant at 14.6% (95% CI 7.4%-21.4%, p < .001).

DISCUSSION

The results from the study support the results from other studies recommending that a PHCCT clinician should be located in ambulance control to identify major trauma patients as early as possible and co-ordinate the response.

Pre-hospital emergency anaesthesia in awake hypotensive trauma patients: beneficial or detrimental?

BACKGROUND

The benefits of pre-hospital emergency anaesthesia (PHEA) are controversial. Patients who are hypovolaemic prior to induction of anaesthesia are at risk of severe cardiovascular instability post-induction. This study compared mortality for hypovolaemic trauma patients (without major neurological injury) undergoing PHEA with a patient cohort with similar physiology transported to hospital without PHEA.

METHODS

A retrospective database review was performed to identify patients who were hypotensive on scene [systolic blood pressure (SBP) < 90 mmHg], and GCS 13-15. Patient records were reviewed independently by two pre-hospital clinicians to identify the likelihood of hypovolaemia. Primary outcome measure was mortality defined as death before hospital discharge.

RESULTS

Two hundred and thirty-six patients were included; 101 patients underwent PHEA. Fifteen PHEA patients died (14.9%) compared with six non-PHEA patients (4.4%), P = 0.01; unadjusted OR for death was 3.73 (1.30-12.21; P = 0.01). This association remained after adjustment for age, injury mechanism, heart rate and hypovolaemia (adjusted odds ratio 3.07 (1.03-9.14) P = 0.04). Fifty-eight PHEA patients (57.4%) were hypovolaemic prior to induction of anaesthesia, 14 died (24%). Of 43 PHEA patients (42.6%) not meeting hypovolaemia criteria, one died (2%); unadjusted OR for mortality was 13.12 (1.84-578.21). After adjustment for age, injury mechanism and initial heart rate, the odds ratio for mortality remained significant at 9.99 (1.69-58.98); P = 0.01.

CONCLUSION

Our results suggest an association between PHEA and in-hospital mortality in awake hypotensive trauma patients, which is strengthened when hypotension is due to hypovolaemia. If patients are hypovolaemic and awake on scene it might, where possible, be appropriate to delay induction of anaesthesia until hospital arrival.

Prehospital Management of Pediatric Hanging

OBJECTIVES

Hanging may inflict laryngotracheal injuries and increase the potential for difficult airway management. We describe the management of pediatric hangings attended by an urban physician-led prehospital trauma service to provide information on a clinical situation encountered infrequently by most acute care clinicians.

METHODS

Retrospective trauma registry-based observational study of all children younger than 16 years attended with hanging as mechanism of injury in the period between 2000 and 2014.

RESULTS

Twenty-three thousand one hundred thirty patients were attended; 2415 (10%) of which were children. Of these, 32 cases (<1%) were pediatric hanging (1 case excluded due to missing data). There were 22 (71%) boys and 9 (29%) girls. Median age was 13 years. There was suicidal intent in 23 (74%) cases, and in 8 (26%) cases, hanging was accidental. There were 17 (55%) deaths, of which 14 (82%) were suicides.The doctor-paramedic team intubated 25 (80%) patients, with a 100% success rate. One (3%) patient was managed with a supraglottic airway device, and 5 (16%) patients did not require any advanced airway management.

CONCLUSIONS

Pediatric hanging is rare, but has a high mortality rate. Attempted suicide is the leading cause of hangings in children and preventive measures should target psychiatric morbidity. Despite concerns about airway edema or laryngeal injury, experienced doctor-paramedic teams had no failed airway attempts.

Outcomes after cancelled helicopter emergency medical service missions due to concurrencies: a retrospective cohort study

BACKGROUND

Appropriate dispatch criteria and helicopter emergency medical service (HEMS) crew decisions are crucial for avoiding over-triage and reducing the number of concurrencies. The aim of the present study was to compare patient outcomes after completed HEMS missions and missions cancelled by the HEMS due to concurrencies.

METHODS

Missions cancelled due to concurrencies (AMB group) and completed HEMS missions (HEMS group) in Western Norway from 2004 to 2013 were assessed. Outcomes were survival to hospital discharge, physiology score in the emergency department, emergency interventions in the hospital, type of department for patient admittance, and length of hospital stay.

RESULTS

Survival to discharge was similar in the two groups. One-third of the primary missions in the HEMS group and 13% in the AMB group were patients with pre-hospital conditions posing an acute threat to life. In a sub group analysis of these patients, HEMS patients were younger, more often admitted to an intensive care unit, and had an increased survival to discharge. In addition, the HEMS group had a greater proportion of patients with deranged physiology in the emergency department according to an early warning score.

CONCLUSION

Patients in the HEMS group seemed to be critically ill more often and received more emergency interventions, but the two groups had similar in-hospital mortality. Patients with pre-hospital signs of acute threat to life were younger and presented increased survival in the HEMS group.

Pre-hospital transfusion of red blood cells in civilian trauma patients

INTRODUCTION

The current management of severely injured patients includes damage control resuscitation strategies that minimise the use of crystalloids and emphasise earlier transfusion of red blood cells (RBC) to prevent coagulopathy. In 2012, London's air ambulance (LAA) became the first UK civilian pre-hospital service to routinely carry RBC to the trauma scene.

OBJECTIVE

To investigate the effect of pre-hospital RBC transfusion (phRTx) on overall blood product consumption.

METHODS

A retrospective trauma database study compares before implementation with after implementation of phRTx in exsanguinating trauma patients transported directly to one major trauma centre. Pre-hospital deaths were excluded. Univariate and multivariate Poisson regression analyses on data subject to multiple imputation were conducted.

RESULTS

We included 137 and 128 patients in the before and after the implementation of phRTx groups, respectively. LAA transfused 304 RBC units (median 2, inter quartile range 1-3). We found a significant reduction in total RBC usage and reduced early use of platelets and fresh-frozen plasma (FFP) after the implementation of phRTx in both univariate (P < 0·001) and multivariate analyses (P < 0·001). No immediate adverse transfusion reactions were identified.

CONCLUSION

Pre-hospital trauma transfusion practice is feasible and associated with overall reduced RBC, platelets and FFP consumption.

Are severely injured trauma victims in Norway offered advanced pre-hospital care? National, retrospective, observational cohort

Background

Studies of severely injured patients suggest that advanced pre‐hospital care and/or rapid transportation provides a survival benefit. This benefit depends on the disposition of resources to patients with the greatest need. Norway has 19 Emergency Helicopters (HEMS) staffed by anaesthesiologists on duty 24/7/365. National regulations describe indications for their use, and the use of the national emergency medical dispatch guideline is recommended. We assessed whether severely injured patients had been treated or transported by advanced resources on a national scale.

Methods

A national survey was conducted collecting data for 2013 from local trauma registries at all hospitals caring for severely injured patients. Patients were analysed according to hospital level; trauma centres or acute care hospitals with trauma functions. Patients with an Injury Severity Score (ISS) > 15 were considered severely injured.

Results

Three trauma centres (75%) and 17 acute care hospitals (53%) had data for trauma patients from 2013, a total of 3535 trauma registry entries (primary admissions only), including 604 victims with an ISS > 15. Of these 604 victims, advanced resources were treating and/or transporting 51%. Sixty percent of the severely injured admitted directly to trauma centres received advanced services, while only 37% of the severely injured admitted primarily to acute care hospitals received these services.

Conclusion

A highly developed and widely distributed HEMS system reached only half of severely injured trauma victims in Norway in 2013.

HEMS dispatch: A systematic review

Introduction

Helicopter emergency medical services dispatch is a contentious issue in modern prehospital services. Whilst the link between helicopter emergency medical services and improved patient outcome is well evidenced, allocation to the most appropriate incidents remains problematic. It is unclear which model of deployment is the most efficient at targeting major trauma and whether this can be improved with a change in dispatch process. The objective of this study was to have an overview of the evidence for dispatch models of helicopter emergency medical services to critically ill or injured patients.

Methods

This systematic review was conducted in accordance with a protocol developed from the PRISMA guidelines. MEDLINE, Embase, CINAHL and the Cochrane library were searched focusing on keywords involving dispatch of helicopter emergency medical services resources.

Results

Ninety-seven articles were screened and 14 articles were eligible for inclusion. Most were of low quality, with three of moderate quality. Heterogeneity in the methodology of included articles precluded meta-analysis, so a narrative review was performed.

Conclusions

This review demonstrates the lack of evidence surrounding helicopter emergency medical services dispatch models. Whilst it is not possible to identify a method of dispatch that will optimize helicopter emergency medical services allocation, common themes within the literature indicate that helicopter emergency medical services use is region specific and dispatch criteria should be designed to match specific systems. Additionally, mechanism of injury as well as physiological data from scene was shown to be the most accurate indicator for helicopter emergency medical services attendance.

Physician staffed helicopter emergency medical service case identification - a before and after study in children

BACKGROUND

Severely injured children may have better outcomes when transported directly to a Paediatric Trauma Centre (PTC). A case identification system using the crew of a physician staffed helicopter emergency medical service (P-HEMS) that identified severely injured children for P-HEMS dispatch was previously associated with high rates of direct transfer. It was theorised that discontinuation of this system may have resulted in deterioration of system performance.

METHODS

Severe paediatric trauma cases were identified from a state based trauma registry over two time periods. In Period A the P-HEMS case identification system operated in parallel with a paramedic dispatcher (Rapid Launch Trauma Co-ordinator-RLTC) operating from a central control room (n = 71). In Period B the paramedic dispatcher operated in isolation (n = 126). Case identification and direct transfer rates were compared as was time to arrival at the PTC.

RESULTS

After cessation of the P-HEMS system the rate of case identification fell from 62 to 31 % (P < 0.001), identification of fatal cases fell from 100 to 47 % (P < 0.001), the rate of direct transfer to a PTC fell from 66 to 53 % (P = 0.076) and the time to arrival in a PTC increased from a median 69 (interquartile range 52 - 104) mins to 97 (interquartile range 56 - 305) mins (P = 0.003). When analysing the rate of direct transfer to a PTC as a function of team composition, after adjusting for age and injury severity scores, there was no change in the rate between the physician and paramedic groups across the two time periods (relative risk 0.92, 95 % CI: 0.44 to 1.41).

DISCUSSION

The parallel identification system improves case identification rates and decreases time to arrival at the PTC, whilst requiring RLTC authorisation preserves the safety and efficiency benefits of centralised dispatch. The model could be extended to adult patients with similar benefits.

CONCLUSIONS

A case identification system relying solely on RLTC paramedics resulted in a significantly lower case identification rate and increased prehospital time with a non-significant fall in direct transfer rate to the PTC. The elimination of the P-HEMS input from the tasking system resulted in worse performance indicators and has the potential for poorer outcomes.

Structure of Rapid Response Car Operations in an Urban Trauma Service

OBJECTIVE

Emergency medical vehicle collisions are an inherent risk for health care providers, patients, and other road users. Air ambulance services often use rapid response cars (RRCs) to maintain operational resilience. We aim to describe the operational concept of London's Air Ambulance (LAA) RRCs and activity over a 1-year period.

METHODS

This was a retrospective dispatch database study. The RRC operational concept, car configuration, and training are also described.

RESULTS

LAA implemented principles from motorsports and aviation including car configuration, training, navigation, and communication. RRCs were activated a total of 2,241 times during the study period (average of 6.1 activations per day). RRCs traveled a total of 22,973 km and a median of 8.7 km (interquartile range = 5-15.1) with blue lights; there were missing data for 123 (5%) activations. Furthermore, the RRCs spent a total of 28,536 minutes with blue lights and a median of 12 minutes (interquartile range = 7-18); there were missing data for 89 (4%) activations. The safety management system included 5 reports, none of which were related to serious RRC incidents.

CONCLUSION

Translating lessons from aviation and motorsports, LAA has developed an RRC operation concept to improve safety and operational capacity. One-year operational data indicate high activity without any serious incidents.