Preoperative video laryngoscopic examination for difficult intubation in obese patients

Anatomical and physiological changes often observed in obese patients increase the risk of difficult tracheal intubation (DTI). In this study, we explored the potential of video-assisted laryngoscopy to prospectively predict DTI in obese patients.

Patients scheduled for general anesthesia with a body mass index (BMI) higher than 30 were included in the study. The El-Ganzouri risk index (EGRI) was calculated during routine preoperative bedside evaluations. An EGRI of ≥ 4 was considered indicative of DTI. Following the application of a local anesthetic agent to the airway, the percentage of glottic opening (POGO) score was obtained using preoperative video laryngoscopy. In the POGO score, visibility of 50% or less of the glottic opening was considered indicative of difficult intubation. Intubation difficulties were assessed using the intubation difficulty scale (IDS), with an IDS score > 5 considered indicative of difficult intubation.

The study included 104 patients with an average BMI of 36.9 ± 4.8. According to the IDS, the incidence of DTI was 30.8% (n = 32). The POGO score displayed a significantly higher positive predictive value and sensitivity compared to the EGRI (p < 0.0001 for both). The ROC analysis showed better discriminative performance for the POGO score than for the EGRI (AUC: 0.868 vs. 0.436; p < 0.001). The preoperative POGO score was correlated with the IDS (r = 0.710, p < 0.001).

Our findings suggest that the POGO score obtained during preoperative video-assisted laryngoscopy is associated with difficult tracheal intubation in obese patients.