Effect of Bougie Versus Endotracheal Tube With Stylet on Successful Tracheal Intubation

Tracheal intubation is a high-risk procedure that is frequently performed in the emergency department (ED), medicine ward, and intensive care unit (ICU). Failure of first-pass success (FPS) when intubating has been shown to be associated with major adverse events,¹ so maximizing FPS is paramount for improving patient outcomes. In 2018, the Bougie Use in Emergency Airway Management (BEAM) trial, a single-center randomized controlled trial, compared FPS with the use of a bougie (tracheal tube introducer) versus an endotracheal tube (ETT) with stylet. The investigators reported an unprecedented high FPS rate of 98% on all airways and 96% on difficult airways when using a bougie, significantly higher than 87% and 82% using the stylet, respectively.² Although this study was large (757 patients), it was limited to a single center with a history of bougie use, so the results may not be generalizable to physicians who are not trained to use bougies.
 
To evaluate this question more broadly, the Bougie or Stylet in Patients Undergoing Intubation Emergently (BOUGIE) trial was designed as a multicenter randomized controlled trial comparing the effect of the bougie versus stylet on FPS in the ED and ICU.³ Of the 1558 patients screened, 1102 were enrolled: 556 in the bougie group and 546 in the stylet group. The primary outcome of FPS was defined as a single successful insertion of the laryngoscope followed by the bougie and ETT or the ETT with stylet. The demographics and underlying reasons for intubation were not significantly different between the groups.
 
The average patient age was 58 years, and the two most common reasons for intubation were altered mental status (44.6%) and acute respiratory failure (31.5%). Over 97% of patients in each group received the assigned intervention. Approximately 60% of the intubations took place in the ED and approximately 40% in the ICU, which closely mirrored the primary specialty of the intubation practitioner. At least one difficult airway characteristic (defined as obesity, body fluid obscuring the glottis, cervical spine immobilization, or facial trauma) was present in 41% of the bougie group and 43% of the stylet group. Residents performed 61.9% of the procedures in the bougie group and 61.4% in the stylet group. Methods of preoxygenation were similar between the groups, as were laryngoscope blade types. Videolaryngoscopy use was also similar between the two groups (75.7% vs. 73.8%). Paralytics were administered to 96.9% of patients in the bougie group and 97.3% in the stylet group.
 
FPS occurred in 80.4% of the bougie group versus 83.0% of the stylet group. No differences were noted in quality of Cormack-Lehane view. Use of a bougie was associated with a slightly longer time from induction to intubation (124 seconds vs. 112 seconds). There were more incidents of oxygen saturation dropping below 80% (11.0% vs. 8.8%) in the bougie group, but this was not significant. There were no differences in other complications between the groups, including new pneumothorax. Several patient-oriented outcomes (e.g., ventilator-free days, ICU-free days, and death before 28 days) all favored the bougie group, although the reason is unclear. Secondary analysis exploring video versus direct laryngoscopy, difficult airway characteristics, incomplete visualization of the larynx, and prior bougie experience all showed no differences between the groups. One notable secondary analysis was use of the definition of FPS used in the BEAM trial.² When applied to the BOUGIE trial, FPS was 88% in both groups.
 
This study has several limitations. First, the clinicians had performed an average of 10 bougie intubations before participating in this trial. This may not be adequate experience with the bougie to see a benefit, and in most sites the bougie was not commonly used before this trial. Intubations using hyperangulated blades, in pediatrics, or in patients with cardiac arrest or abnormal airway anatomy were not included. The secondary outcomes may be underpowered. And the study does not provide information as to whether the bougie is useful after a failed airway attempt. The authors concluded that, among critically ill patients requiring intubation, the use of a bougie did not improve FPS over a stylet.
 
This trial was a huge undertaking and was well-designed to answer a clinically relevant question. Not only was their primary outcome important, but they undertook several secondary analyses to address additional questions. The BOUGIE trial opens up several areas for future research, such as whether the bougie would be helpful after a failed attempt and whether the results of bougie first intubation would be different with primary training and additional clinician experience. Interestingly, a bougie was used on 50.5% of second attempts in the stylet group. The reason for this is unknown, but it may mean that the bougie is a popular airway rescue device. If a bougie is potentially helpful where intubation using a stylet fails, clinicians should become proficient at using it as a primary airway tool, similar to supraglottic airways and other rescue devices and procedures. Overall, this trial does not show a difference in FPS in critically ill patients intubated with bougie versus stylet with similar secondary outcomes. However, a much higher FPS success may be possible with the use of a bougie as the primary intubation tool in systems that have more experience with the bougie.²

References

1. Russotto V, Myatra SN, Laffey JG, et al; INTUBE Study Investigators. Intubation practices and adverse peri-intubation events in critically ill patients from 29 countries. JAMA. 2021 Mar 23;325(12):1164-1172. https://pubmed.ncbi.nlm.nih.gov/33755076/
2. Driver BE, Prekker ME, Klein LR, et al. Effect of use of a bougie vs endotracheal tube and stylet on first-attempt intubation success among patients with difficult airways undergoing emergency intubation: a randomized clinical trial. JAMA. 2018 Jun 5;319(21):2179-2189. https://pubmed.ncbi.nlm.nih.gov/29800096/
3. Driver BE, Semler MW, Self WH, et al; BOUGIE Investigators and the Pragmatic Critical Care Research Group. Effect of use of a bougie vs endotracheal tube with stylet on successful intubation on the first attempt among critically ill patients undergoing tracheal intubation: a randomized clinical trial. JAMA. 2021 Dec 28;326(24):2488-2497. https://pubmed.ncbi.nlm.nih.gov/34879143/