Improving rigid fiberoptic intubation: a comparison of the Bonfils Intubating Fiberscope™ with a novel modification

Abstract

BackgroundThe Bonfils intubating fiberscope has a limited upward tip angle of 40° and requires retromolar entry into the hypopharynx. These factors may make its use less desirable when managing the difficult airway because most anesthesia providers are well versed in midline oral intubation rather than the lateral retromolar approach. The Center for Advanced Technology and Telemedicine at the University of Nebraska Medical Center has developed a novel fiberscope with a more anterior 60° curve to allow for easier midline insertion and intubation. The objective of this work was to evaluate the novel fiberscope, in comparison to the Bonfils intubating fiberscope, in terms of use and function in difficult airway intubation.MethodsTwenty-two anesthesia providers participated in simulated intubations of a difficult airway mannequin to compare the Bonfils intubating fiberscope with the novel curved Boedeker intubating fiberscope. The intubations were assessed based upon the following variables: recorded Cormack Lehane airway scores, requests for cricoid pressure, time to intubation, number of intubation attempts and success or failure of the procedure.ResultsParticipants using the Bonfils fiberscope recorded an average Cormack Lehane (CL) airway score of 1.67 ± 1.02 (median = 1); with the novel fiberscope, the recorded average airway grade improved to 1.18 ± 0.50 (median = 1). The difference in airway scores was not statistically significant (p = 0.34; Fishers Exact Test comparing CL grades 1&2 vs. 3&4). There was, however, a statistically significant difference in intubation success rates between the two devices. With the Bonfils fiberscope, 68% (15/22) of participants were successful in intubation compared to a 100% success rate in intubation with the novel fiberscope (22/22) (p = 0.008). After the intubation trial, the majority of participants (95%) indicated a preference for the novel fiberscope (n = 20).ConclusionsWith this data, we can infer that the novel fiberscope curvature appears to improve or maintain the quality of an intubation attempt (airway score, cricoid pressure requirement, intubation time, number of attempts, placement success). The data indicate that the novel fiberscope offers a superior intubation experience to currently available best practices. The instrument was well received and would be welcomed by most study participants should the device become clinically available in the future.

Learning curve and performance in simulated difficult airway for the novel C-MAC® video-stylet and C-MAC® Macintosh video laryngoscope: A prospective randomized manikin trial

“…A potential explanation for the superior results seen with the VS over other rigid stylets could be the flexible tip, which allows for easier navigation of the airway. Preceding studies have shown improved success rates using rigid stylets with different curvatures [ 17 ]. An additional reason for faster and easier intubation with the VS compared to the VL is that the pathway to the cords to be navigated by the ETT have already been visualized by the VS.…”

“…Subsequent trials also showed a similar but shorter median total time to intubation between the two devices. On the sixth trial, the total time to intubation was similar between devices (VS 12 [9.25-15.75] sec vs VL 14 [13][14][15][16][17] sec, P = 0.21); however, the total time to intubation was significantly shorter compared to the first trial for each corresponding device (VS 21 sec vs 12.0s sec P = 0.0028 and VL 21.5 sec vs 14 sec P = 0.027).…”

Comparison of haemodynamic responses to intubation: Flexible fibreoptic bronchoscope versus bonfils rigid intubation endoscope

“…The flexible fibreoptic intubation seems to cause a lesser haemodynamic response because we can better centralize its mobile distal tip thus minimizing the stimulation of the laryngeal surface. Bonfils rigid intubation endoscope has an immobile tip[ 1 20 ] thus having a higher probability of stimulating the laryngeal surface. The intubation time with bonfils rigid intubation endoscope might be longer, as we have to manipulate its immobile tip with our wrist, to visualize the vocal cords.…”

A comparison of the transillumination-assisted technique versus midline approach technique in novices: a prospective randomized controlled trial about the Bonfils intubation fiberscope

“…In this study, the average intubation time with the BIF was 50.0–52.8 s, which was close to the upper limit of the time range of 23–52 s reported previously [ 6 , 12 , 14 ]. Differences in approach such as left molar approach, para-tongue approach, or modified laryngoscopic structure [ 15 ] are possible factors affecting intubation time. Different methods can be used to judge successful intubation, such as the carbon dioxide test or lung auscultation, which may have different durations and lead to different time points, thereby exerting different effects on the results.…”