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

Effect of Air Transport Delay on Mortality in Critical Illness: A Population-Based Cohort Study

OBJECTIVE

For critically ill patients in remote areas, we assessed the association of transport delay via fixed wing air ambulance on 30-day mortality, excluding interhospital transports.

METHODS

This was a retrospective cohort analysis of all such adult transports in Manitoba, Canada, over 5.4 years. Causal mediation analysis was used, with the Acute Physiology and Chronic Health Evaluation II Acute Physiology Score at the destination intensive care unit as the mediator. The covariates were age, sex, comorbidities, socioeconomic status, and physiologic variables from the sending site.

RESULTS

The primary cohort was composed of 554 patients; 113 (20.4%) died within 30 days. The total transport delay (mean ± standard deviation) was 5.1 ± 1.7 hours. Compared with no delay, the average 5-hour transport delay was associated with an odds ratio for mortality of 1.34 with a 95% confidence interval from 40% lower to 270% higher, with 60% of the influence of total travel time attributable to worsening of patients' acute physiologic status during the delay in intensive care unit admission due to transport.

CONCLUSIONS

Although these findings provide insufficient evidence for an effect of fixed wing air transport delay on mortality among critically ill patients, they underscore the need for additional and larger studies on this topic.

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.

Optimizing the Availability of Enhanced Prehospital Care Team Resources

OBJECTIVE

After recent developments within the North West Air Ambulance (NWAA), we undertook a service evaluation to determine if resource use could be improved. We sought to answer the following questions: (1) At what time of day do major trauma incidents occur in the North West of England? 2) Do current NWAA operating hours meet the needs of these major trauma patients? 3) Where do major trauma incidents occur in the North West of England? and 4) Are current NWAA resources optimally located to meet the needs of these major trauma patients?

METHODS

We reviewed records from the Trauma Audit and Research Network database for the North West of England (the counties of Cheshire, Merseyside, Greater Manchester, Cumbria, and Lancashire) between January 1, 2017, and December 31, 2017. These data were supplemented by incident records from the North West Ambulance Service National Health Service Trust. Analysis was undertaken using Excel (Microsoft, Redmond, WA) and MapInfo Pro (Pitney Bowes, Stamford, CT). A survey will be conducted to give insight into the level of cover provided by other UK helicopter emergency medical services.

RESULTS

Data from 2,318 incidents were analyzed. Major trauma occurs in higher numbers at certain times of day, varies from weekday to weekend, and takes place in higher concentrations in certain locations, appearing related to population density.

CONCLUSION

There is a significant difference between the current trauma care provision and the demand of major trauma incidents. The findings of this study suggest an expansion in cover provided by the NWAA may be appropriate.

Characteristics of patients treated by the Danish Helicopter Emergency Medical Service from 2014-2018: a nationwide population-based study

Background

A national Helicopter Emergency Medical Service (HEMS) was introduced in Denmark in 2014 to ensure the availability of physician-led critical care for all patients regardless of location.

Appropriate dispatch of HEMS is known to be complex, and resource utilisation is a highly relevant topic. Population-based studies on patient characteristics are fundamental when evaluating and optimising a system. The aim of this study was to describe the patient population treated by the Danish HEMS in terms of demographics, pre-hospital diagnostics, severity of illness or injury, and the critical care interventions performed.

Method

The study is a retrospective nationwide population-based study based on data gathered from the Danish HEMS database. We included primary missions resulting in a patient encounter registered between October 1^st 2014 and April 30^th 2018.

Results

Of 13.391 dispatches registered in the study period we included 7133 (53%) primary missions with patient encounter: 4639 patients were air lifted to hospital, 174 patients were escorted to hospital by the HEMS physician in an ambulance, and in 2320 cases HEMS assisted the ground crew on scene but did not escort the patient to hospital. Patient age ranged from 0-99 years and 64% of the population were men. The median age was 60 years.

The main diagnostic groups were cardio-vascular emergencies (41%), trauma (23%) and neurological emergencies (16%). In 61% of the cases, the patient was critically ill/injured corresponding to a NACA (National Advisory Committee for Aeronautics) score between 4 and 7 (both included). In more than one third of the missions a critical care intervention was performed. Ultrasound examination and endo-tracheal intubation were the critical care interventions most frequently performed (21% and 20%, respectively).

Conclusion

The national Danish HEMS primarily attends severely ill or injured patients and often perform critical care interventions. In addition, the Danish HEMS provides rapid transport to highly specialised treatment for patients in the more rural parts of the country.

Patients with cardio-vascular emergencies, trauma and neurological emergencies are among those patient groups most commonly seen.

We conclude that the overall dispatch profile appears appropriate but emphasise that continuous development and refinement is essential.