Association of Number of Physician Postgraduate Years With Patient Intubation Outcomes in the Emergency Department

Evidence suggests that tracheal intubation performed by residents may be a risk factor for poor intubation-related patient outcomes.^1,2 However, the incidence of intubation-related adverse events is relatively low,³ precluding investigators from elucidating the relationship between training levels and intubation performance in the emergency department (ED). This knowledge gap has hindered efforts to develop a consensus on the degree to which between-physician differences in intubation success and adverse event rates should be permitted for the safety of critically ill patients, while providing sufficient training opportunities for residents. We examined the association between the intubator’s number of postgraduate years (PGYs) and intubation outcomes in a large multicenter prospective study of ED patients who underwent airway management.

This analysis used data from the second Japanese Emergency Airway Network prospective cohort study, designed to characterize airway management in EDs across Japan. The study setting, methods, and variables measured were described previously,¹ and further details are provided in the eMethods in the Supplement. The institutional review board at each participating institution approved the study and waived the need for informed consent. This study followed the STROBE reporting guideline.

We included data from 15 institutions for all patients who underwent emergency intubation between 2012 and 2019. Outcome measures were first-pass success and intubation-related adverse events (overall, major, and minor).¹ To determine the association of physician PGYs with each intubation outcome, we constructed multivariable linear and logistic regression models. All P values of <.05 were considered statistically significant (2-tailed).

Of 11 297 eligible patients, the median age was 71 years (IQR, 56-81) and 7001 patients (62%) were men (Table 1). Overall, 4480 patients (40%) underwent intubation by transitional-year residents (PGY1 to PGY2) and 3588 (31%) underwent intubation by physicians (PGY3 to PGY5). The overall first-pass success rate was 71%. Intubations performed by a less experienced physician had a significantly lower first-pass success rate (Table 2), with an adjusted risk difference of −23% (95% CI, −30% to −16%) for PGY1 residents compared with PGY6 or greater physicians. These associations remained in logistic regression models (adjusted odds ratio, 0.30 [95% CI, 0.22 to 0.41] for PGY1 residents vs PGY6 or greater physicians). Overall, 1802 patients (16%) had intubation-related adverse events. A lower number of PGYs was also associated with a higher rate of any adverse events (adjusted risk difference, 7% [95% CI, 3% to 11%] for PGY1 residents vs PGY6 or greater physicians).

In this study, 8068 patients (71%) were intubated by residents (PGY1 to PGY5). Therefore, our findings present critical issues that should be addressed to improve patient safety in the ED. Our large multicenter cohort study adds to earlier findings² by suggesting an association between intubations performed by residents and poorer intubation outcomes. To our knowledge, few studies have investigated the association between physician training level and adverse events,⁴ potentially because of the low incidence of adverse events.³ The association with adverse events in our study is plausible because less experienced physicians may take longer to intubate a patient and may apply extra force to oral structures.⁵ Although there is currently no consensus on the degree of the differences in success rate by PGYs that can be allowed for patient safety, the approximately 20% lower success rate by PGY1 physicians observed here is not acceptable for ED patients. To improve intubation skills and patient outcomes, several approaches have been proposed, including training in the operating room setting, simulation-based curricula, and close supervision by attending physicians.⁶

Our study has several limitations, including the appropriateness of the use of PGYs as a marker for training levels, unmeasured confounders (eg, intubation resources, neck circumstance), and limited generalizability to other ED settings. Regardless, because a large proportion of patients were intubated by residents, our findings underscore the importance of improving both resident training and current airway management strategies for critically ill patients in the ED.

Accepted for Publication: February 15, 2022.

Published: April 8, 2022. doi:10.1001/jamanetworkopen.2022.6622

Open Access: This is an open access article distributed under the terms of the CC-BY License. © 2022 Goto T et al. JAMA Network Open.

Corresponding Author: Tadahiro Goto, MD, PhD, MPH, Department of Clinical Epidemiology and Health Economics, School of Public Health, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan (tag695@mail.harvard.edu).

Author Contributions: Drs Goto and Oka had full access to all the data in the study and take responsibility for the integrity of the data and the accuracy of the data analysis. Drs Goto and Oka contributed equally and are considered co–first authors of this work.

Concept and design: Goto, Oka, Okamoto, Hasegawa.

Acquisition, analysis, or interpretation of data: Goto, Oka, Hagiwara, Watase, Hasegawa.

Drafting of the manuscript: Goto, Oka, Okamoto.

Critical revision of the manuscript for important intellectual content: Goto, Oka, Hagiwara, Watase, Hasegawa.

Statistical analysis: Goto.

Administrative, technical, or material support: Goto, Okamoto, Hagiwara, Watase.

Supervision: Goto, Okamoto, Hasegawa.

Conflict of Interest Disclosures: None reported.

Meeting Presentation: This study was presented at the Annual Meeting of the Japanese Association for Acute Medicine; November 19 to 21, 2018; Yokohama, Japan.