Defibrillation and external pacing in flight: incidence and implications

Oxygen accumulation and associated dangers in rescue helicopters

BACKGROUND

At the time of the COVID-19 pandemic, devastating incidents increased due to frequent oxygen administration to patients. The dangers associated with the use of oxygen, especially through local enrichments and formation of "oxygen clouds", have been well understood for years. Nevertheless, dramatic incidents continue to occur, since fire hazard increases exponentially with oxygen concentrations above 23%. Rescue helicopters are at a particular high risk, because of technical reasons such as oxygen use in a very small space, surrounded by kerosene lines, electronic relays and extremely hot surfaces.

METHODS

In this study three different sized rescue helicopter models (Airbus H135, H145 and MD902) were examined. Oxygen enrichment in the cabin was measured with an oxymeter during a delivery rate of 15 l/min constant flow for 60 min. Furthermore, the clearance of the enriched atmosphere was tested in different situations and with different ventilation methods. To make the airflow visible, a fog machine was used to fill the helicopter cabin.

RESULTS

Oxygen accumulation above 21% was detected in every helicopter. After 10-15 min, the critical 23% threshold was exceeded in all three aircrafts. The highest concentration was detected in the smallest machine (MD902) after 60 min with 27.4%. Moreover, oxygen clouds persisted in the rear and the bottom of the aircrafts, even when the front doors were opened. This was most pronounced in the largest aircraft, the H145 from Airbus Helicopters. Complete and rapid removal of elevated oxygen concentrations was achieved only by cross-ventilation within 1 min.

CONCLUSIONS

Oxygen should be handled with particular care in rescue helicopters. Adapted checklists and precautions can help to prevent oxygen accumulation, and thus, fatal incidents. To our knowledge, this is the first study, which analyzed oxygen concentrations in different settings in rescue helicopters.

Emergency management of patients with ST-segment elevation myocardial infarction in Eastern Austria: a descriptive quality control study

Background

Myocardial infarction is a time-critical condition and its outcome is determined by appropriate emergency care. Thus we assessed the efficacy of a supra-regional ST-segment elevation myocardial infarction (STEMI) network in Easternern Austria.

Methods

The Eastern Austrian STEMI network serves a population of approx. 766.000 inhabitants within a region of 4186 km². Established in 2007, it now comprises 20 pre-hospital emergency medical service (EMS) units (10 of these physician-staffed), 4 hospitals and 3 cardiac intervention centres. Treatment guidelines were updated in 2012 and documentation within a web-based STEMI registry became mandatory. For this retrospective qualitative control study, data from February 2012–April 2015 was assessed.

Results

A total of 416 STEMI cases were documented, and 99% were identified by EMS within 6 (4.0–8.0) minutes after arrival. Median time loss between onset of pain and EMS call was 54 (20–135) minutes; response, pre-hospital and door-to-balloon times were 14 (10–20), 46 (37–59) and 45 (32–66) minutes, respectively. When general practitioners were involved, time between onset of pain and balloon inflation significantly increased from 180 (135–254) to 218 (155–348) minutes (p < .001). A pre-hospital time < 30 min was achieved in 25.8% of all patients during the day vs. 11.6% during the night (p < .001). Three hundred forty-five patients (83%) were subjected to primary percutaneous coronary intervention (PPCI), and 6.5% were thrombolysed by EMS. Pre-hospital complication rate was 18% (witnessed cardiac arrest 7%, threatening arrhythmias 6%, cardiogenic shock 5%). Twenty-four hours and hospital mortality rate were 1.2 and 2.8%, respectively.

Discussion

Optimal patient care and subsequently outcome of STEMI is strongly determined by a short patient-decision time to call EMS and by the first medical contact to balloon time (FMCBT). Supra-regional networks are key in order to increase the efficacy and efficiency of health care. The goal of 120 min FMCBT was achieved in 78% of our patients immediately managed by EMS, thus indicating room for improvement.

Conclusion

In conclusion, results from the Eastern Austrian STEMI network shed light on the necessity of increasing patient awareness in order to minimize any time loss derived by delayed EMS calls. Involvement of family physicians resulted in prolonged FMCBT. A stronger utilization of rescue helicopters could further improve the efficacy of this supra-regional network. Nevertheless PPCI rates, time intervals and outcome rates compare well with international benchmarks.

Exploration of a Preflight Acuity Scale for Fixed Wing Air Ambulance Transport

INTRODUCTION

Despite the prevalence of fixed wing medical flights for specialized care and repatriation, few acuity rating scales exist aimed at the prediction of adverse in-flight medical events. An acuity scoring system can provide information to flight crews, allowing for staffing enhancements, protocol modifications, and flight planning, with the aim of improving patient care, outcomes, and preventing losses to providers because of costly diversions.

METHODS

Our medical crew developed an acuity scale, which was applied retrospectively to 296 patients transported between January 2016 and March 2017. Patients received scores based on conditions identified during the preflight medical report, the initial patient assessment, demographics, and flight factors.

RESULTS

Five patients were identified as high-risk transports based on our scale. Three patients suffered adverse events according to our defined criteria, 2 of which occurred before transport and 1 during transport. The 3 patients suffering adverse events did not receive a score that indicated adverse events in flight.

CONCLUSION

Our scale was not predictive of adverse events in flight. However, it did illuminate factors worthy of consideration. Consideration of these factors may have prevented adverse events.

Challenges and Resources for New Critical Care Transport Crewmembers: A Descriptive Exploratory Study

OBJECTIVE

The purpose of this study was to identify the challenges new crewmembers experience in the critical care transport (CCT) environment and to determine the most valuable resources when acclimating to the transport environment. To date, no study has focused on the unique challenges nor the resources most effective in CCT training.

METHODS

This descriptive exploratory study was conducted with a convenience survey sent to the 3 largest professional CCT organizations: the Association of Air Medical Services, the Air and Surface Transport Nurses Association, and the Association of Critical Care Transport.

RESULTS

The study survey responses revealed that more education and training are needed. Novice crewmembers identified areas in safety, communication, environment, and crew resource management as particularly challenging. Responses also validate the need for more simulation training, especially for CCT of low-volume/high-risk patient populations.

CONCLUSION

Results of this survey provide valuable insight for improving training effectiveness of health care professionals transitioning to the CCT environment. More information regarding best practice on the frequency and timing of CCT simulation training should be collected, particularly for simulations completed in the transport environment.