Comparison of endotracheal intubation learning curves with tracheoscopic ventilation tube for simulated difficult intubation between expert and novice anesthesiologists.

Abstract

Background: Tracheoscopic ventilation tube (TVT) is a specially designed single-lumen endotracheal tube with a camera. It was developed to facilitate endobronchial blocker insertion without bronchoscopy; its ability to explore anatomy received attention for difficult intubations. To clarify the feasibility of TVT in difficult intubation, we evaluated the learning curves of intubation between novice and expert.Methods: 182 patients who presented as Cormack-Lehane (CL) grade IIb and III with cervical in-line stabilization, and 4 trainees (2 novices, 2 experts) at single tertiary care teaching university hospital.All trainees performed intubation with TVT during laryngoscopy. Intubation attempts were limited to two times, each within 30 seconds. For every attempt, trainees visualized an imaginary pathway from the teeth to vocal cords and then shaped the stylet. Intubation was confirmed by three successive ETCO 2 measurements > 30 mmHg. Using CUSUM analysis, the trial was continued until every trainee reached an acceptable failure rate.Results: Patients were constituted with 94.5% CL grade IIb and 5.5% grade III. The median number of acceptable performances (10% of the acceptable failure rate) was 36. Overall failure rate was 5.5% (95%CI: 2.2-8.8%), with 6.9% (95%CI: 2.0-11.8%) for novices and 3.7% (95%CI: 0.0-7.8%, P=0.165, Cohen's h=0.14) for experts. Intubation time was longer in novices by about 3 seconds compared to experts (mean difference=2.8, 95%CI: 1.3-4.3, P<0.001, Cohen's d=0.57).Conclusions: Intubation with TVT in CL grades IIb and III was easy to learn and could be an alternative for difficult intubation. It required small cases to reach acceptable performance, and provided a short learning period even for novice anesthesiologists, with failure rates similar to those of experienced anesthesiologists.