Long-term follow-up of trauma patients before and after implementation of a physician-staffed helicopter: A prospective observational study

Natural Experiment Outcomes Studies in Rotor Wing Air Medical Transport: Systematic Review and Meta-Analysis of Before-and-After and Helicopter-Unavailable Publications From 1970 to 2022

OBJECTIVE

Helicopter emergency medical services (HEMS) is widely used for prehospital and interfacility transport, but there is a paucity of HEMS outcomes data from studies using randomized controlled trial designs. In the absence of robust randomized controlled trial evidence, judgments regarding HEMS potential benefit must be informed by observational data. Within the study design set of observational analyses, the natural experiment (NE) is notable for its high potential methodologic quality; NE designs are occasionally denoted "quasi-experimental." The aim of this study is to examine all NE outcomes studies in the HEMS literature and to discern what lessons can be learned from these potentially high-quality observational data.

METHODS

HEMS NE studies were identified during the development of a new HEMS Outcomes Assessment Research Database (HOARD). HOARD was constructed using a broad-ranging search of published and gray literature resources (eg, PubMed, Embase, and Google Scholar) that used variations of the terms "helicopter EMS," "air ambulance," and "air medical transport." Among the 221 studies ultimately included in HOARD, 16 NE publications describing 13 sets of observational data comprising myriad diagnostic groups were identified. Of these 16 HEMS NEs, 4 HEMS NE studies assessing trauma outcomes were used in a meta-analysis. A meta-analysis was also performed of 4 HEMS NE studies.

RESULTS

Although the disparity of studies (in terms of both case mix and end points) precluded the generation of a pooled effect estimate of an adjusted mortality benefit of HEMs versus ground emergency medical services, HEMS was found to be associated with outcomes improvement in 8 of the 13 cohorts.

CONCLUSION

The weight of the NE evidence supports a conclusion of some form of HEMS-mediated outcomes improvement in a variety of patient types. Meta-analysis of 4 HEMS NE studies assessing trauma outcomes generated a model with acceptable heterogeneity (I2 = 43%, Q test: P = .16), which significantly (P < .01) favored HEMS use with a pooled HEMS survival odd ratio estimate of 1.66 (95% confidence interval, 1.23-2.22).

Overcoming distance: an exploration of current practices of government and charity-funded critical care transport and retrieval organizations

BACKGROUND

For critically ill and injured patients, timely access to definitive care is associated with a reduction in avoidable mortality. Access to definitive care is significantly affected by geographic remoteness. To overcome this disparity, a robust critical care transport (CCT) or retrieval system is essential to support the equity of care and overcome the tyranny of distance. While critical care transport or retrieval systems have evolved over the years, there is no universally accepted system or standard, which has led to considerable variation in practices. The objective of this mixed-methods study was to identify and explore the current clinical, operational, and educational practices of government and charity-funded critical care transport and retrieval organizations operating across access- and weather- challenged geography.

METHODS

This study utilized a mixed-methods approach comprising a rapid review of the literature and semi-structured interviews with identified subject matter experts (SME).

RESULTS

A total of 44 articles and 14 interviews with SMEs from six different countries, 12 different services/systems, and seven operational roles, including clinicians (physician, paramedic, and nurse), educator, quality improvement, clinical governance, clinical informatics and research, operations manager, and medical director were included in the narrative analysis. The study identified several themes including deployment, crew composition, selection and education, clinical governance, quality assurance and quality improvement and research.

CONCLUSION

This mixed-methods study underscores the paucity of literature describing current clinical, operational, and educational practices of government or charity-funded CCT or retrieval programs operating across access- and weather- challenged geography. While many common themes were identified including clearly defined mission profiles, use of dedicated or specialized transport teams, central coordination, rigorous selection processes, service-sponsored graduate education, and strong clinical governance, there is little consensus and considerable variation in current practices. Further research is needed to identify and harmonize best practices within the CCT and retrieval environments.

Trauma Versus Nontrauma Patients Treated by the Danish Helicopter Emergency Medical Service: A Register-Based Study of Patient Characteristics, Hospitalization, and Mortality

OBJECTIVE

Helicopter emergency medical services (HEMS) are part of many emergency health care systems, ensuring specialized treatment on scene. An accurate use is important for improved resource utilization. The aim of this study was to describe patient characteristics, hospitalization, and mortality in trauma and nontrauma patients seen by the Danish HEMS teams.

METHODS

The study is a registry-based study presenting data from the national Danish HEMS database. We included all HEMS missions from October 1, 2014, to April 30, 2018.

RESULTS

A total of 13,391 HEMS entries were registered, and 5,524 cases were included in the study. Trauma patients were younger (38 vs. 63 years) and had a lower level of comorbidities (Charlson Comorbidity Index 0: 82% vs. 58%) compared with nontrauma patients. More nontrauma cases were classified with a severity score corresponding to a critical emergency. They also had a higher 30-day mortality compared with trauma patients (26% vs. 11%).

CONCLUSION

This national study demonstrated differences in demographics, the severity profile, and mortality among trauma compared with nontrauma patients that could possibly indicate an overuse of HEMS for minor trauma cases. The results might suggest that educational efforts and a review of the current dispatch guidelines could be of importance when trying to improve the use of HEMS.

Costing of helicopter emergency services- a strategic simulation based on the example of a German rural region

BACKGROUND

Helicopter emergency services (HEMS) are of increasing relevance for emergency medical services (EMS) of developed countries. Despite the known cost intensity of HEMS, there is only very limited knowledge of its cost dynamics and structures. This averts an efficient resource allocation of scarce EMS resources in an environment that is characterized by socio-political, medical and economic challenges. The objective of this study is the exemplary modeling of HEMS cost structures.

METHODS

We defined three scenarios with each five variations to illustrate different models of HEMS provision. Into these, we included varying availability times, technical features for off-shore or alpine rescue and differing numbers of operations. Cost data is based on a broad literature review and primary data from a German HEMS organization resulting in a cost function. We calculated average costs per primary missions and total costs, whilst differentiating between fixed, jump-fixed, variable and maintenance costs for every scenario variation. The costs were further used to evaluate the profitability of operations by executing a break-even analysis.

RESULTS

Average costs per HEMS operation decrease with increasing number of operations due to the digression of fixed costs. Depending on special equipment, availability times or other assumptions, total costs differ significantly with the different scenario variations. For the basic scenario (12 h of operations per day), the total costs per year of HEMS are 1,697,546.20 € and the unit costs are 763.41 € per primary mission at 1200 primary and 92 secondary operations. At an engine-runtime based revenue of 70 € per minute, global cost covering is possible after 728 missions (c.p.).

CONCLUSIONS

Considering a revenue of 70 € per minute of engine run-time, HEMS can be operated at a profit for companies. However, the necessary remuneration represents a high financial effort for the societal cost bearers of helicopter emergency services. This leads to the question of the cost-benefit ratio of HEMS, which could be approached in further researches by using this model. The valuation of mission costs also opens a new view to the framework of HEMS disposition procedures and criteria. This cost analysis enhances the necessity of better planning of HEMS networks to use available resources efficiently in order to improve social welfare.

What clinical crew competencies and qualifications are required for helicopter emergency medical services? A review of the literature

BACKGROUND

Patients served by Helicopter Emergency Medical Services (HEMS) tend to be acutely injured or unwell and in need of stabilisation followed by rapid and safe transport. It is therefore hypothesised that a particular clinical crew composition is required to provide appropriate HEMS patient care. A literature review was performed to test this hypothesis.

METHODS

MEDLINE, EMBASE, Web of Science and the Cochrane Database of Systematic Reviews were systematically searched from 1 January 2009 to 30 August 2019 to identify peer-reviewed articles of relevance. All HEMS studies that mentioned 'staffing', 'configuration', 'competencies' or 'qualifications' in the title or abstract were selected for full-text review.

RESULTS

Four hundred one studies were identified. Thirty-eight studies, including one systematic review and one randomised controlled trial, were included. All remaining studies were of an observational design. The vast majority of studies described clinical crews that were primarily doctor-staffed. Descriptions of non-doctor staff competencies were limited, with the exception of one paramedic-staffed model.

CONCLUSIONS

HEMS clinical crews tended to have a wider range of competencies and experience than ground-based crews, and most studies suggested a patient outcome benefit to HEMS provision. The conclusions that can be drawn are limited due to study quality and the possibility that the literature reviewed was weighted towards particular crewing models (i.e. primarily doctor-staffed) and countries. There is a need for trial-based studies that directly compare patient outcomes between different HEMS crews with different competencies and qualifications.

Time Course of Hoist Operations by the Search and Rescue Helicopter Service in Southeast Norway

INTRODUCTION

Optimal dispatch of emergency medical services relies on accurate time estimates of the various prehospital stages. Hoist rescue work time intervals performed by the search and rescue (SAR) helicopter service in Norway have not been studied to date. We aimed to describe the epidemiologic, operational, and medical aspects of the SAR service in southeast Norway. To complement the prehospital timeline, we performed simulated hoist operations.

METHODS

We reviewed time and patient descriptors and medical interventions in hoist operations performed at a SAR base over 5 y. In addition, a simulation study measuring hoist rescue time intervals was performed. Data are presented as mean±SD, except National Advisory Committee for Aeronautics (NACA) scores, which are presented as modes.

RESULTS

There were 148 hoist operations performed during the study period, involving 180 patients. Time to take-off was 13±7 min. There were 88 patients (49%) who were injured; 53 (29%) had a medical condition, and 39 (22%) were evacuees. The mode of the NACA score was 3. Forty-five patients (25%) had an NACA score of 4 to 6. Medical interventions were performed on 77 patients (43%) in 73 operations (49%). Nine patients (5%) were endotracheally intubated, and 1 thoracostomy was performed. The simulated rescuer access time was 4±2 min, the simulated anesthesiologist access time was 6±2 min, and the simulated hoist extrication time was 13±2 min.

CONCLUSIONS

Hoist rescue was performed in 10% (n=148) of the SAR operations. New information about hoist extrication time intervals can improve rescue helicopter dispatch accuracy.

The Danish helicopter emergency medical service database: high quality data with great potential

Background

The Danish Helicopter Emergency Medical Service (HEMS) is part of the Danish pre-hospital response offering advanced patient care on scene and during rapid transport to definitive care.

Monitoring HEMS performance and the quality of critical care has high national as well as international priority underlining the need for research in this field.

The data quality of the Danish HEMS database is unknown. Furthermore, a set of quality indicators (QI) developed by an international collaboration group (EQUIPE) potentially for use in physician-staffed EMS, has recently been presented.

The aim of the current study was to present the design and data quality of the Danish helicopter database, and to evaluate the coverage of available variables in the database according to the QIs proposed.

Method

The study included all helicopter dispatches between October 1st 2014 and April 30th 2018.

The database layout and data entering procedure, as well as the key variables and data completeness were described. Furthermore, missing data and misclassifications were addressed.

Lastly, the 26 QIs proposed by the EQUIPE-collaboration were evaluated for coverage in the HEMS database.

Results

A total of 13,392 missions were included in the study. The database includes a broad spectrum of mission- and patient-specific data related to the pre-hospital pathway of acutely ill or injured patients in a national coverage. Missing data for the majority of variables is less than 6.5%. The percentage of completed report forms has increased over time and reached 99.9% in 2018.

Misclassification were observed for 294 patients in the study period corresponding to 3,7%.

Less than half of the QIs proposed by the EQUIPE-collaboration group were directly available from the database.

Conclusions

Helicopter Emergency Medical Services in Denmark are a new and sparsely investigated health care provider. The database contains nearly all missions dispatched by the five regional Emergency Medical Dispatch Centres. Generally, the data quality is considered high with great potential for future research.

Potential quality indicators as proposed by the EQUIPE-collaboration group could inspire the configuration and design of the next version of Hemsfile creating an even more solid basis for research and quality improvement.

Electronic supplementary material

The online version of this article (10.1186/s13049-019-0615-5) contains supplementary material, which is available to authorized users.

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.

Overview of doctor-staffed ambulance use in Japan: a nationwide survey and 1-week study

Aim

In Japan, standard prehospital care is provided by emergency medical services teams. Doctor-staffed ambulances play a role in facilitating the immediate treatment of critically ill patients to increase the survival rates. However, little is known about their activities. We revealed the present situation of doctor-staffed ambulances in Japan.

Methods

First, we surveyed all the fire departments in Japan and determined whether a doctor-staffed ambulance was present within their district boundary. Second, we surveyed hospitals that operate doctor-staffed ambulances in their system to list their activities during a 1-week period.

Results

Of 133 hospitals that operated a doctor-staffed ambulance, 73 (55%) replied to our questionnaire. Only 26 (36%) of them provided 24-h ambulance deployment. Additionally, 51 (70%) of hospitals bore the operational costs of ambulances. Within 1 week, 345 doctor-staffed ambulances were dispatched, but 97 (28%) were cancelled. In total, 62 patients (28%) were diagnosed with cardiac arrest, 48 (19%) with trauma or burns, 36 (15%) with stroke, and 22 (9%) with acute coronary syndrome; 159 (58%) were transferred to a tertiary emergency medical center.

Conclusions

Doctor-staffed ambulances have the advantage of deployment at night and in urban areas compared to doctor-staffed helicopters. Among the 73 hospitals that responded to the questionnaire, doctor-staffed ambulances were dispatched almost as frequently as doctor-staffed helicopters. However, doctor-staffed ambulances did not receive adequate funding. Future data collection is necessary to determine the efficacy of doctor-staffed ambulances among hospitals that operate this service.

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.

Quality of life following trauma before and after implementation of a physician-staffed helicopter

Background

Implementation of a physician‐staffed helicopter emergency medical service (PS‐HEMS) in Denmark was associated with lower 30‐day mortality in severely injured trauma patients and less time on social subsidy. However, the reduced 30‐day mortality in severely injured patients might be at the expense of a worse functional outcome and quality of life (QoL) in those who survive. The aim of this study was to investigate the effect of a physician‐staffed helicopter on long‐term QoL in trauma patients.

Methods

Prospective, observational study including trauma patients who survived at least 3 years after injury. A 5‐month period prior to PS‐HEMS implementation was compared with the first 12 months after PS‐HEMS implementation. QoL was assessed 4.5 years after trauma by the SF‐36 questionnaire. Primary endpoint was the Physical Component Summary score.

Results

Of the 1994 patients assessed by a trauma team, 1521 were eligible for inclusion in the study. Of these, 566 (37%) gave consent to participate and received a questionnaire by mail, and 402 (71%) of them returned the questionnaire (n = 114 before PS‐HEMS; n = 288 after PS‐HEMS implementation). Older patients, women and patients with trauma in the after PS‐HEMS period were more likely to return the questionnaire. No significant association between QoL and period (before vs. after PS‐HEMS) was found; the Physical Component Summary scores were 50.0 and 50.9 in the before and after PS‐HEMS periods, respectively (P = 0.47). We also found no difference on multivariable analysis with adjustment for sex, age and injury severity score.

Conclusion

No significant difference in QoL among trauma patients was found after implementation of a PS‐HEMS.

Effect of the number of request calls on the time from call to hospital arrival: a cross-sectional study of an ambulance record database in Nara prefecture, Japan

OBJECTIVES

In Japan, ambulance staff sometimes must make request calls to find hospitals that can accept patients because of an inadequate information sharing system. This study aimed to quantify effects of the number of request calls on the time interval between an emergency call and hospital arrival.

DESIGN AND SETTING

A cross-sectional study of an ambulance records database in Nara prefecture, Japan.

CASES

A total of 43 663 patients (50% women; 31.2% aged 80 years and over): (1) transported by ambulance from April 2013 to March 2014, (2) aged 15 years and over, and (3) with suspected major illness.

PRIMARY OUTCOME MEASURES

The time from call to hospital arrival, defined as the time interval from receipt of an emergency call to ambulance arrival at a hospital.

RESULTS

The mean time interval from emergency call to hospital arrival was 44.5 min, and the mean number of requests was 1.8. Multilevel linear regression analysis showed that ∼43.8% of variations in transportation times were explained by patient age, sex, season, day of the week, time, category of suspected illness, person calling for the ambulance, emergency status at request call, area and number of request calls. A higher number of request calls was associated with longer time intervals to hospital arrival (addition of 6.3 min per request call; p<0.001). In an analysis dividing areas into three groups, there were differences in transportation time for diseases needing cardiologists, neurologists, neurosurgeons and orthopaedists.

CONCLUSIONS

The study revealed 6.3 additional minutes needed in transportation time for every refusal of a request call, and also revealed disease-specific delays among specific areas. An effective system should be collaboratively established by policymakers and physicians to ensure the rapid identification of an available hospital for patient transportation in order to reduce the time from the initial emergency call to hospital arrival.