Intubation difficulty scale contributors and time delay in clinical practice.

ABSTRACT: The intubation difficulty scale (IDS) includes 7 contributors that provide a comprehensive assessment of difficult intubation. However, the effect of each contributor is unclear, and the scale has not been revalidated recently and has not been validated in orient. This study determined the duration of successful intubation (DSI) for each of these 7 contributors.The patients were intubated by attending anesthesiologists. The duration and other data were recorded by 2 research assistants. Anaesthesiologists reported the IDS and their perceptions. A linear mixed-effects model with a DSI was constructed using IDS factors.In total, 1095 patients were enrolled. The average DSI was 23.9 ±â€Š21.8 seconds (37.1% IDS = 0). All 7 factors were independently associated with duration, with the exception of vocal cord adduction. The best model was as follows: DSI (in seconds) = 15.2 + 31.1 (number of additional attempts) + 26.2 (number of additional operators) + 11.4 (number of alternative techniques) + 7.9 (increased lift force) + 4.9 (external laryngeal pressure) + 3.5 (Cormack grade 1). The mixed models were similar except for the regression coefficient for the number of alternative techniques that decreased from 11.4 to 6.9 seconds.We confirmed that each IDS contributor affects the DSI and validated a prediction model with 6 IDS contributors. This prediction model may facilitate the development of strategic plans for critical airway management. Furthermore, it could improve simulations and monitor learning progress and help provide valuable feedback.

Betel-Nut Chewing Increases Difficulty in Tracheal Intubation.

BACKGROUND: Betel-nut chewing (BC) causes oral submucous fibrosis (OSF), and this leads to difficult tracheal intubation (DI). Unanticipated DI was reported in chewers with apparently normal preoperative airway evaluations (PAEs). This analysis aims to investigate whether BC is an independent risk on DI besides the common DI risk prediction factors. METHODS: After the approval of Institutional Review Board and the written informed consent were obtained, 2,682 patients were enrolled in a cohort. PAEs, intubation difficulty scale (IDS), intubation time, and perceived DI were recorded prospectively. All 805 male patients received classical intubation, 307 with BC and 498 without BC were analyzed. Data were analyzed by Student's t-test and chi-square test. Stepwise logistic regression was performed to identify BC effects on IDS adjusting for related factors with WEKA (Waikato Environment for Knowledge Analysis; Machine Learning Group at the University of Waikato, Hamilton, New Zealand). RESULTS: Fewer BC patients were Cormack-Lehane (CL) grade I (38.9% vs. 47.6%) or IDS degree 〞Easy〞 (24.8% vs. 33.5%). Compared with IDS degree 〞Easy〞, patients in the BC group had a significantly higher odds ratio (OR) for 〞Slight + Moderate-Major〞 degree than in the non-BC group (adjusted OR, 1.75; 95% CI, 1.15-2.68). Compared with CL grade I, patients with BC was an independent risk for II (adjusted OR, 1.53; 95% CI, 1.02-2.32) and IV (adjusted OR, 3.25; 95% CI 1.01-10.49). Otherwise, patient's age ≥ 46 and the presence of teeth were also significant risk factors for IDS degree 〞Slight + Moderate-Major〞. CONCLUSION: BC increased not only the tracheal intubation difficulty in patients with apparent OSF but also in patients with PAEs. BC is an independent risk factor besides the commonly used DI prediction factors. We suggest physicians operating on BC patients to be better prepared for DI.