Does Body Mass Index Reduction by Bariatric Surgery Affect Laryngoscopy Difficulty During Subsequent Anesthesia?

The effect of body mass index (BMI) reduction following bariatric surgery on subsequent airway management has not been investigated. This study aimed to investigate the association between BMI reduction and airway assessment and management measured by Mallampati class (MC) and laryngoscopy grade (LG).

We conducted a retrospective study over 6 years to compare the BMI changes, MC and LG in patients having weight reduction bariatric surgery followed by subsequent surgery. Data was extracted from the anesthesia records of patients undergoing laparoscopic band insertion (LBI) and laparoscopic sleeve gastrectomy (LSG). Difficult airway was defined as Malampati class 3 and 4 on a 1-4 difficulty scale or laryngoscopy grade >2 on a 1-4 difficulty scale and need for unplanned fiberoptic intubation. Changes in these variables were correlated with weight reduction. Statistical analysis included t test, univariante, and multivariant logistic regression.

Five hundred forty-six patients underwent LSG and 83 patients had LBI during the study period. Of those patients, 65 patients had subsequent surgical procedures after the bariatric procedure. Of the 65 patients identified, 62 were eligible. BMI decreased by approximately13 kg/m² (p = 0.000) which roughly represents a 30 % reduction between the two surgical procedures. Mallampati class decreased significantly (p = 0.000) while laryngoscopy grade did not (p = 0.419).

Our study revealed that a significant reduction in BMI was associated with a significant decrease in Mallampati class. There was no significant decrease in laryngoscopy grade, and there was no case of unplanned fiberoptic intubation.