Feasibility of Prehospital Rapid Sequence Intubation in the Cabin of an AW169 Helicopter

Efficacy of endotracheal intubation in helicopter cabin vs. ground: a systematic review and meta-analysis

BACKGROUND

Pre-hospital endotracheal intubation (ETI) is a sophisticated procedure with a comparatively high failure rate. Especially, ETI in confined spaces may result in higher difficulty, longer times, and a higher failure rate. This study analyses if Helicopter Emergency Medical Services (HEMS) intubation (time-to) success are influenced by noise, light, and restricted space in comparison to ground intubation. Available literature reporting these parameters was very limited, thus the reported differences between ETI in helicopter vs. ground by confronting parameters such as time to secure airway, first pass success rate and Cormack-Lehane Score were analysed.

METHODS

A systematic review and meta-analysis were conducted using PUBMED, EMBASE, Cochrane Library, and Ovid on October 15th, 2022. The database search provided 2322 studies and 6 studies met inclusion and quality criteria. The research was registered with the International Prospective Register of Systematic Reviews (CRD42022361793).

RESULTS

A total of six studies were selected and analysed as part of the systematic review and meta-analysis. The first pass success rate of ETI was more likely to fail in the helicopter setting as compared to the ground (82,4% vs. 87,3%), but the final success rate was similar between the two settings (96,8% vs. 97,8%). The success rate of intubation in literature was reported higher in physician-staffed HEMS than in paramedic-staffed HEMS. The impact of aircraft type and location inside the vehicle on intubation success rates was inconclusive across studies. The meta-analysis revealed inconsistent results for the mean duration of intubation, with one study reporting shorter intubation times in helicopters (13,0s vs.15,5s), another reporting no significant differences (16,5s vs. 16,8s), and a third reporting longer intubation times in helicopters (16,1s vs. 15,0s).

CONCLUSION

Further research is needed to assess the impact of environmental factors on the quality of ETI on HEMS. While the success rate of endotracheal intubation in helicopters vs. on the ground is not significantly different, the duration and time to secure the airway, and Cormack-Lehane Score may be influenced by environmental factors. However, the limited number of studies reporting on these factors highlights the need for further research in this area.

Sky-High Safety? A Qualitative Study of Physicians' Experiences of Patient Safety in Norwegian Helicopter Emergency Services

BACKGROUND

Patients treated and transported by Helicopter Emergency Medical Services (HEMS) are prone to both flight and medical hazards, but incident reporting differs substantially between flight organizations and health care, and the extent of patient safety incidents is still unclear.

METHODS

A qualitative descriptive study based on in-depth interviews with 8 experienced Norwegian HEMS physicians from 4 different bases from February to July 2020 using inductive qualitative content analysis. The study objectives were to explore the physicians' experience with incident reporting and their perceived areas of risk in HEMS.

RESULTS/FINDINGS

The HEMS physicians stated that the limited number of formal incident reports was due to the "nature of the HEMS missions" and because reports were mainly relevant when deviating from procedures, which are sparse in HEMS. The physicians preferred informal rather than formal incident reporting systems and reporting to a colleague rather than a superior. The reasons were ease of use, better feedback, and less fear of consequences. Their perceived areas of risk were related to all the phases of a HEMS mission: the physician as the team leader, medication errors, the handover process, and the helicopter as a work platform.

CONCLUSIONS

The sparse, informal, and fragmented incident reporting provides a poor overview of patient safety risks in HEMS. Focusing on organizational factors and system responsibility and research on environmental and contextual factors are needed to further improve patient safety in HEMS.

Prehospital tracheal intubations by anaesthetist-staffed critical care teams: a prospective observational multicentre study

BACKGROUND

Prehospital tracheal intubation is a potentially lifesaving intervention, but is associated with prolonged time on-scene. Some services strongly advocate performing the procedure outside of the ambulance or aircraft, while others also perform the procedure inside the vehicle. This study was designed as a non-inferiority trial registering the rate of successful tracheal intubation and incidence of complications performed by a critical care team either inside or outside an ambulance or helicopter.

METHODS

This observational multicentre study was performed between March 2020 and September 2021 and involved 12 anaesthetist-staffed critical care teams providing emergency medical services by helicopter in Denmark, Norway, and Sweden. The primary outcome was first-pass successful tracheal intubations.

RESULTS

Of the 422 drug-assisted tracheal intubations examined, 240 (57%) took place in the cabin of the ambulance or helicopter. The rate of first-pass success was 89.2% for intubations in-cabin vs 86.3% outside. This difference of 2.9% (confidence interval -2.4% to 8.2%) (two sided 10%, including 0, but not the non-inferiority limit Δ=-4.5) fulfils our criteria for non-inferiority, but not significant superiority. These results withstand after performing a propensity score analysis. The mean on-scene time associated with the helicopter in-cabin procedures (27 min) was significantly shorter than for outside the cabin (32 min, P=0.004).

CONCLUSIONS

Both in-cabin and outside the cabin, prehospital tracheal intubation by anaesthetists was performed with a high success rate. The mean on-scene time was shorter in the in-cabin helicopter cohort.

CLINICAL TRIAL REGISTRATION

NCT04206566.

A 6-year case series of resuscitative thoracotomies performed by a helicopter emergency medical service in a mixed urban and rural area with a comparison of blunt versus penetrating trauma

Background

Resuscitative thoracotomy (RT) is an intervention that can be performed in the prehospital setting for relieving cardiac tamponade and/or obtaining vascular control of suspected sub-diaphragmatic haemorrhage in patients in traumatic cardiac arrest. The aim of this retrospective case study is to compare the rates of return of spontaneous circulation (ROSC) in RTs performed for both penetrating and blunt trauma over 6 years in a mixed urban and rural environment.

Methods

The electronic records of a single helicopter emergency medical service were reviewed between 1st June 2015 and 31st May 2021 for RTs. Anonymised data including demographics were extracted for relevant cases. Data were analysed with independent t-tests and Χ² tests. A p value < 0.05 was considered statistically significant.

Results

Forty-four RTs were preformed within the 6 years (26 for blunt trauma). Eleven ROSCs were achieved (nine blunt, two penetrating) but no patient survived to discharge. In contrast to RTs for penetrating trauma, twelve of the RTs for blunt trauma had a cardiac output present on arrival of the prehospital team (p = 0.01). Two patients had an RT performed in a helicopter (one ROSC) and two on a helipad (both achieving ROSC), likely due to the longer transfer times seen in a more rural setting. Four of the RTs for blunt trauma (15%) were found to have a cardiac tamponade versus seven (39%) of the penetrating trauma RTs.

Conclusion

Prehospital RT remains a procedure with low rates of survival but may facilitate a ROSC to allow patients to reach hospital and surgery, particularly when distances to hospitals are greater. A higher-than-expected rate of cardiac tamponade was seen in RTs for blunt trauma, although not caused by a right ventricular wound but instead due to underlying vessel damage.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13049-022-00997-4.

Feasibility of Prehospital Emergency Anesthesia in the Cabin of an AW169 Helicopter Wearing Personal Protective Equipment During Coronavirus Disease 2019

OBJECTIVE

Prehospital emergency anesthesia in the form of rapid sequence intubation (RSI) is a critical intervention delivered by advanced prehospital critical care teams. Our previous simulation study determined the feasibility of in-aircraft RSI. We now examine whether this feasibility is preserved in a simulated setting when clinicians wear personal protective equipment (PPE) for aerosol-generating procedures (AGPs) for in-aircraft, on-the-ground RSI.

METHODS

Air Ambulance Kent Surrey Sussex is a helicopter emergency medical service that uses an AW169 cabin simulator. Wearing full AGP PPE (eye protection, FFP3 mask, gown, and gloves), 10 doctor-paramedic teams performed RSI in a standard "can intubate, can ventilate" scenario and a "can't intubate, can't oxygenate" (CICO) scenario. Prespecified timings were reported, and participant feedback was sought by questionnaire.

RESULTS

RSI was most commonly performed by direct laryngoscopy and was successfully achieved in all scenarios. The time to completed endotracheal intubation (ETI) was fastest (287 seconds) in the standard scenario and slower (370 seconds, P = .01) in the CICO scenario. The time to ETI was not significantly delayed by wearing PPE in the standard (P = .19) or CICO variant (P = .97). Communication challenges, equipment complications, and PPE difficulties were reported, but ways to mitigate these were also reported.

CONCLUSION

In-aircraft RSI (aircraft on the ground) while wearing PPE for AGPs had no significant impact on the time to successful completion of ETI in a simulated setting. Patient safety is paramount in civilian helicopter emergency medical services, but the adoption of in-aircraft RSI could confer significant patient benefit in terms of prehospital time savings, and further research is warranted.