Helicopter emergency medical service dispatch in older trauma: time to reconsider the trigger?

Prehospital interventions and outcomes in traumatic cardiac arrest: a population-based cohort study using the Danish Helicopter Emergency Medical Services data

BACKGROUND AND IMPORTANCE

Traumatic cardiac arrest is associated with poor prognosis, and timely evidence-based treatment is paramount for increasing survival rates. Physician-staffed helicopter emergency medical service use in major trauma has demonstrated improved outcomes. However, the sparsity of data highlights the necessity for a comprehensive understanding of the epidemiology of traumatic cardiac arrest.

OBJECTIVES

The primary objective of the present study was to evaluate survival and return of spontaneous circulation (ROSC) and to investigate the characteristics of patients with traumatic cardiac arrest assessed by the Danish HEMS.

DESIGN

This was a population-based cohort study based on data from the Danish helicopter emergency medical service database.

SETTINGS AND PARTICIPANTS

The study included all patients assessed by the Danish helicopter emergency medical services between 2016 and 2021.

OUTCOME MEASURES AND ANALYSIS

Data were analysed using descriptive statistics, non-parametric testing and logistic regression analyses. Descriptive analysis of prehospital interventions included cardiopulmonary resuscitation, defibrillation, airway management, administration of blood products, and thoracic decompression. The primary outcome was 30-day survival, and the key secondary outcome was prehospital ROSC.

MAIN RESULTS

A total of 223 patients with TCA were included. The median age was 54 years (IQR 34-68), and the majority were males. Overall, 23% of patients achieved prehospital ROSC, and the 30-day survival rate was 4%. Factors associated with an increased likelihood of ROSC were an initial shockable cardiac rhythm, odds ratio (OR) of 3.78 (95% CI 1.33-11.00) and endotracheal intubation, OR 7.10 (95% CI 2.55-22.85).

CONCLUSION

This study highlights the low survival rates observed among patients with traumatic cardiac arrest assessed by helicopter emergency medical services. The findings support the positive impact of an initial shockable cardiac rhythm and endotracheal intubation in improving the likelihood of ROSC. The study contributes to the limited literature on traumatic cardiac arrests assessed by physician-staffed helicopter emergency services. Finally, the findings emphasise the need for further research to understand and improve outcomes in this subgroup of cardiac arrest.

Ambulance service recognition of health inequalities and activities for reduction: An evidence and gap map of the published literature

Background

Emergency medical services (EMS) are often patients' first point of contact for urgent and emergency care needs. Patients are triaged over the phone and may receive an ambulance response, with potential conveyance to the hospital. A recent scoping review suggested disparities in EMS patient care in the United States. However, it is unknown how health inequalities impact EMS care in other developed countries and how inequalities are being addressed.

Objectives

This rapid evidence map of published literature aims to map known health inequalities in EMS patients and describe interventions reducing health inequalities in EMS patient care.

Methods

The search strategy consisted of EMS synonyms and health inequality synonyms. The MEDLINE/PubMed database was searched from 1 January 2010 to 26 July 2022. Studies were included if they described empirical research exploring health inequalities within ambulance service patient care. Studies were mapped on to the EMS care interventions framework and Core20PLUS5 framework. Studies evaluating interventions were synthesised using the United Kingdom Allied Health Professions Public Health Strategic Framework.

Results

The search strategy yielded 771 articles, excluding duplicates, with two more studies added from hand searches. One hundred studies met the inclusion criteria after full-text review. Inequalities in EMS patient care were predominantly situated in assessment, treatment and conveyance, although triage and response performance were also represented. Studies mostly explored EMS health inequalities within ethnic minority populations, populations with protected characteristics and the core issue of social deprivation. Studies evaluating interventions reducing health inequalities (n = 5) were from outside the United Kingdom and focused on older patients, ethnic minorities and those with limited English proficiency. Interventions included community paramedics, awareness campaigns, dedicated language lines and changes to EMS protocols.

Conclusions

Further UK-based research exploring health inequalities of EMS patients would support ambulance service policy and intervention development to reduce health inequality in urgent and emergency care delivery.

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.

Differences in time-critical interventions and radiological examinations between adult and older trauma patients: A national register-based study

BACKGROUND

Older trauma patients are reported to receive lower levels of care than younger adults. Differences in clinical management between adult and older trauma patients hold important information about potential trauma system improvement targets. The aim of this study was to compare prehospital and early in-hospital management of adult and older trauma patients, focusing on time-critical interventions and radiological examinations.

METHODS

Retrospective analysis of the Norwegian Trauma Registry for 2015 through 2018. Trauma patients 16 years or older met by a trauma team and with New Injury Severity Score of 9 or greater were included, dichotomized into age groups 16 years to 64 years and 65 years or older. Prehospital and emergency department clinical management, advanced airway management, chest decompression, and admission radiological examinations was compared between groups applying descriptive statistics and appropriate statistical tests.

RESULTS

There were 9543 patients included, of which 28% (n = 2711) were 65 years or older. Older patients, irrespective of injury severity, were less likely attended by a prehospital doctor/paramedic team (odds ratio [OR], 0.64; 95% confidence interval [CI], 0.57-0.71), conveyed by air ambulance (OR, 0.65; 95% CI, 0.58-0.73), and transported directly to a trauma center (OR, 0.86; 95% CI, 0.79-0.94). Time-critical intervention and primary survey radiological examination rates only differed between age groups among patients with New Injury Severity Score of 25 or greater, showing lower rates for older adults (advanced airway management: OR, 0.60; 95% CI, 0.47-0.76; chest decompression: OR, 0.46; 95% CI, 0.25-0.85; x-ray chest: OR, 0.54; 95% CI, 0.39-0.75; x-ray pelvis: OR, 0.69; 95% CI, 0.57-0.84). However, for the patients attended by a doctor/paramedic team, there were no management differences between age groups.

CONCLUSION

Older trauma patients were less likely to receive advanced prehospital care compared with younger adults. Older patients with very severe injuries received fewer time-critical interventions and radiological examinations. Improved dispatch of doctor/paramedic teams to older adults and assessment of the impact the observed differences have on outcome are future research priorities.

LEVEL OF EVIDENCE

Therapeutic/Care Management; Level III.

Visualized analysis of research on helicopter emergency medical service

BACKGROUND

Numerous studies have confirmed that helicopter emergency medical services (HEMS) play a positive role in prehospital care. However, few studies have used rigorous bibliometric tools to analyze the knowledge structure and distribution of HEMS research.

OBJECTIVES

The purpose of this study was to use bibliometric methods to conduct a quantitative and qualitative analysis of the HEMS-related literature and to determine the research status and hotspots of HEMS research.

METHODS

CiteSpace was used for bibliometric analysis of the HEMS-related literature retrieved from the Web of Science database from 1989 to 2021.

RESULTS

A total of 1378 HEMS-related literature were included. Collaboration among countries, authors, and institutions needs to be strengthened. The topics in HEMS research have mainly focused on the effectiveness of helicopter emergency medical services for trauma patients and the comparison of transport effectiveness between helicopters and ground emergency medical services on trauma patient transport. Research over the past 10 years has mainly focused on the application of HEMS in patients with trauma, myocardial infarction, cerebral apoplexy, application of tracheal intubation technology in HEMS, and advanced airway management. In recent years, HEMS research trends have mainly included out-of-hospital cardiac arrest, and transport.

CONCLUSIONS

CiteSpace was used to visualize and analyze the HEMS-related literature, which visually reflected the research status and hot spots, providing references for the topic selection and development direction of HEMS research.

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.