Can experienced paramedics perform tracheal intubation at cardiac arrests? Five years experience of a regional air ambulance service in the UK

doi:10.1016/j.resuscitation.2009.07.023

Resuscitation

Volume 80, Issue 12, December 2009, Pages 1342-1345

https://doi.org/10.1016/j.resuscitation.2009.07.023 Get rights and content

Abstract

Aims

Paramedic tracheal intubation has been reported to carry a high failure rate and morbidity. A comparison between doctor and paramedic-led intubation at out-of-hospital cardiac arrests (OHCA) was conducted to assess whether this finding was observed in our clinical practice.

Methods

Retrospective review of all medical OHCA attended by the Warwickshire and Northamptonshire Air Ambulance (WNAA) over a 64-month period. Cases were identified and divided into doctor-led or paramedic-led groups. Self-reported intubation failure rate, morbidity and clinical outcome were observed and compared. Paramedic exposure to tracheal intubation was assessed.

Results

286 cases of medical OHCA were identified, 199 (69.6%) were doctor-led and 87 (30.4%) paramedic-led. Paramedic and doctor-led crews intubated an equivalent proportion of cases (Para-led 60.7% [37] vs. Dr-led 62.8% [98]; p = 0.89) and no significant difference in failure rate was observed (Para-led 2.7% [1 case, 95% CI 0.0–7.9%] vs. Dr-led 3.1% [3 cases, 95% CI 0.0–6.5%]; p = 1). No morbidity from failure-to-intubate was recorded, and equal rates of return of spontaneous circulation (ROSC) were observed (Para-led 20.7% [18] vs. Dr-led 20.6% [41]; p = 0.89). Paramedics operating with the WNAA were found to have a higher exposure to tracheal intubation (WNAA 0.03 TT/shift vs. unselected paramedics 0.004 TT/shift).

Conclusions

Experienced paramedics regularly operating with physicians have a low tracheal intubation failure rate at OHCA, whether practicing independently or as part of a doctor-led team. This is likely due to increased and regular clinical exposure.

Introduction

The vast majority of out-of-hospital cardiac arrests (OHCA) are attended by ambulance personnel (paramedic or technician). Airway management is vital to successful resuscitation and tracheal intubation is still perceived as the optimal method, facilitating continuous chest-compressions and guarding against aspiration of gastric content.¹ In the UK placement of a tracheal tube (TT) may be performed by either a doctor, or in their absence, a paramedic in line with Joint Royal College Ambulance Liaison Committee (JRCALC) guidelines.²

Despite the primacy of airway management and the development of structured training programmes, research has repeatedly demonstrated that paramedics have a higher failure rate of intubation than medical practitioners. Reported failure rates range from 15 to 30% for paramedics, even in optimal conditions,3, 4, 5, 6, 7 compared with 3–6% in the clinical setting for doctors.8, 9, 10 Infrequent use of advanced airway skills (mean 1 intubations/paramedic/year; Deakin, personal communication, data in press) and an inability to obtain sufficient hospital-based training have been cited as root causes for the discrepancy.³ These data, combined with concerns about resultant morbidity, including hypoxaemia during intubation and un-recognised oesophageal intubation, have led to calls for a cessation in paramedic intubation and even the use of tracheal tubes (TTs) in pre-hospital care.3, 11, 12, 13, 14, 15

Warwickshire and Northamptonshire Air Ambulance (WNAA) is based in the UK, serving a mixed urban and rural population in excess of 1.2 million. WNAA operates one helicopter operating 10 h a day, 7 days a week during daylight hours. It attends a full-range of pre-hospital emergencies, including cardiac arrest, either as a primary responder or to back-up a crew already on-scene. The service operates with two crew mixes: either doctor and paramedic, or double paramedic crew. Allocation of crew mix is dependant on availability of staff rather than a mission category specific basis.

Paramedics operating in this critical care environment are selected via both senior recommendation and psychometric assessment, and they undergo 40 h additional clinical training before starting. Operating on WNAA, they are exposed to a wide range of pathology and are frequently involved with experienced clinicians performing advanced airway management including rapid sequence induction (RSI). Doctors operating on the service must comply with strict eligibility requirements (Appendix A).

Through its varied crew mix and non-prescriptive case allocation, the service offers a unique way of assessing and comparing the performance of doctor and paramedic-led crews in the pre-hospital environment.

Section snippets

Methods

We undertook a retrospective review of all missions flown by the WNAA between 1st October 2003 and 19th January 2009 (64 months; 4362 active missions). All cases of cardiac arrest were identified via tasking category and manual review of individual case narratives (JF). Exclusion criteria included inactive missions (stop call, stood-down, aborted due to weather, failure to locate case), non-medical-cardiac arrests, respiratory-only arrests, cases where a do-not-attempt resuscitation (DNAR)

Results

286 cases of medical-cardiac arrest were eligible for inclusion. 199 (69.6%) were doctor-led and 87 (30.4%) paramedic-led. In 26 (29.9%) paramedic-led and 43 (21.6%) doctor-led missions the patient was clearly deceased, or a decision was made not to commence resuscitation (p = 0.18) (see Fig. 1).² These were omitted from the analysis. The remaining cases were demonstrated to be demographically comparable (p = non-significant re: age, sex and on-scene order). No cases with missing primary outcome

Discussion

This study shows an essentially equal rate of successful tracheal intubation between doctor and paramedic-led teams at OHCA. No morbidity was reported from either failed or successful intubations and equal rates of ROSC were observed in both groups indicating comparable clinical performance. Multiple previous studies have demonstrated a higher failure rate in paramedics than doctors. Our data run contrary to this, and add evidence to the view that previously reported discrepancies are likely

Conclusion

Conflict of interest

None.

Acknowledgement

We would like to thank Nick Parsons for his help with the statistical analyses.

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Cited by (23)

Advanced airway management in out of hospital cardiac arrest: A systematic review and meta-analysis
2018, American Journal of Emergency Medicine
Citation Excerpt :
In total data from 539,146 patients were included (Table 1). Details on the individual excluded studies are listed in Table S1 [13-48]. Each study was then screened for risk of bias and methodological quality using the Cochrane Collaboration's tool for assessing the risk of bias for RCTs and the ROBINS-I tool for non-randomised studies (Table S2).
To assess the difference in survival and neurological outcomes between endotracheal tube (ETT) intubation and supraglottic airway (SGA) devices used during out-of-hospital cardiac arrest (OHCA).
A systematic search of five databases was performed by two independent reviewers until September 2018. Included studies reported on (1) OHCA or cardiopulmonary resuscitation, and (2) endotracheal intubation versus supraglottic airway device intubation. Exclusion criteria (1) stimulation studies, (2) selectively included/excluded patients, (3) in-hospital cardiac arrest. Odds Ratios (OR) with random effect modelling was used. Primary outcomes: (1) return of spontaneous circulation (ROSC), (2) survival to hospital admission, (3) survival to hospital discharge, (4) discharge with a neurologically intact state.
Twenty-nine studies (n = 539,146) showed that overall, ETT use resulted in a heterogeneous, but significant increase in ROSC (OR = 1.44; 95%CI = 1.27 to 1.63; I² = 91%; p < 0.00001) and survival to admission (OR = 1.36; 95%CI = 1.12 to 1.66; I² = 91%; p = 0.002). There was no significant difference in survival to discharge or neurological outcome (p > 0.0125). On sensitivity analysis of RCTs, there was no significant difference in ROSC, survival to admission, survival to discharge or neurological outcome (p > 0.0125). On analysis of automated chest compression, without heterogeneity, ETT provided a significant increase in ROSC (OR = 1.55; 95%CI = 1.20 to 2.00; I² = 0%; p = 0.0009) and survival to admission (OR = 2.16; 95%CI = 1.54 to 3.02; I² = 0%; p < 0.00001).
The overall heterogeneous benefit in survival with ETT was not replicated in the low risk RCTs, with no significant difference in survival or neurological outcome. In the presence of automated chest compressions, ETT intubation may result in survival benefits.
Hands-off time during insertion of six airway devices during cardiopulmonary resuscitation: A randomised manikin trial
2011, Resuscitation
Citation Excerpt :
Unsurprisingly, the success rate for endotracheal intubation in pre-hospital settings mainly depends on the operators’ skills and experience.6–11 But even in experienced hands, unrecognised oesophageal intubation remains a non-trivial risk, especially in pre-hospital settings24—and is associated with a 95% mortality in children and an 80% mortality in adults.25,26 In our study, a full third of the tube placements in manikins were actually unrecognised esophageal intubations, a fraction that would be completely unacceptable in patients.
Cardiopulmonary resuscitation (CPR) guidelines recommend limiting interruptions of chest compressions because prolonged hands-off (i.e., non-compression) time compromises tissue perfusion. 2010 European Resuscitation Council guidelines suggest that chest compressions should be paused less than 10 s during airway device insertion.
With approval of the local ethics committee of the Medical University of Vienna and written informed consent, we recruited 40 voluntary emergency medical technicians, none of whom had advanced airway management experience. After a standardised audio-visual lecture and practical demonstration, technicians performed airway management with each six airway devices (endotracheal tube, Combitube, EasyTube, laryngeal tube, Laryngeal Mask Airway, and I-Gel) during on-going chest compressions in a randomised sequence on a Resusci Anne Advanced Simulator. Data were analysed using a mixed-effects model accounting for the repeated measurements and pair-wise comparisons among the airway devices.
The hands-off time associated with airway management using an endotracheal tube (including all intubation attempts) was 48 s (95% confidence interval: 43–53). The hands-off time for airway management using a laryngeal tube was 8.4 (3.4–16.4) s, Combitube 10.0 (4.9–15.1) s, EasyTube 11.4 (6.4–16.4) s, LMA 13.3 (8.2–18.3) s and for I-Gel 15.9 (10.8–20.9) s. Hands-off time was significantly longer with the conventional endotracheal tube than with any of the other airway systems. Only a third of the technicians successfully inserted an endotracheal tube whereas all of them successfully positioned each supraglottic device.
Supraglottic devices appear to be a reasonable emergency airway management strategy, even for inexperienced personnel.
Performance and skill retention of intubation by paramedics using seven different airway devices-A manikin study
2011, Resuscitation
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Deakin et al. reported that paramedics perform ETI infrequently.18 Similarly, a recent study by Fullerton et al. found no significantly higher failure rate of intubation in experienced paramedics compared to physicians.29 Therefore the risk factor for ETIs performed by paramedics appears to lie in the degree of training and practice of the paramedic.
Endotracheal intubation (ETI) is the most widespread method for emergency airway management. Several studies reported that ETI requires considerable skill and experience and if performed incorrectly, may result in serious adverse events. Unrecognized tube misplacement or oesophageal intubation is associated with high prehospital morbidity. This study investigates the usability of supraglottic airway devices compared to ETI and the skill retention of 41 previously inexperienced paramedics following training using a manikin model.
41 paramedics participated in this study. None had prior experience in airway management, apart from bag-valve ventilation. After a standardised audio-visual lecture lasting 45 min, the paramedics participated in a practical demonstration using the advanced patient simulator SimMan^® (Laerdal Medical, Stavanger, Norway). Afterwards, paramedics were instructed to perform airway-management using seven different techniques to secure the airway (ETI, Laryngeal mask unique [LMA], Proseal, Laryngeal tube disposable [LT-D^®], I-Gel^®, Combitube^®, and EasyTube^®) following a randomized sequence. Participants underwent reassessment after 3 months without any further training or practice in airway-management.
During the initial training session, ETI was successfully performed in 78% of cases, while 3 months later the success rate was 58%. For the supraglottic airway devices, five out of six were successfully used by all paramedics at both time points, the exception being Proseal^®. Our data show successful skill retention (success rate: 100%) after 3 months for five out of six supraglottic airway devices. Time to ventilation (T3) was significantly less for LMA, LT-D^® and I-Gel^® at all time points compared to ETI.
ETI performed by inexperienced paramedics is associated with a low success rate. In contrast, supraglottic airway devices like LMA, LT-D^®, I-Gel^®, Combitube^® and EasyTube^® are fast, safe and easy-to-use. Within the limitations of a manikin-study, this study suggests that inexperienced medical staff might benefit from using supraglottic airway devices for emergency airway management.
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^☆: A Spanish translated version of the abstract of this article appears as Appendix in the online version at doi:10.1016/j.resuscitation.2009.07.023.

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Clinical paperCan experienced paramedics perform tracheal intubation at cardiac arrests? Five years experience of a regional air ambulance service in the UK☆

Abstract

Aims

Methods

Results

Conclusions

Introduction

Section snippets

Methods

Results

Discussion

Conclusion

Conflict of interest

Acknowledgement

Prehosp Emerg Care

Ann Emerg Med

Ann Emerg Med

Ann Emerg Med

Resuscitation

Ann Emerg Med

Resuscitation

Advanced life support

Securing the pre-hospital airway: a comparison of laryngeal mask insertion and tracheal intubation by UK paramedics

Emerg Med J

Clinical paper
Can experienced paramedics perform tracheal intubation at cardiac arrests? Five years experience of a regional air ambulance service in the UK☆