Comparison of endotracheal tube cuff pressure changes using air versus nitrous oxide in anesthetic gases during laparoscopic abdominal surgeries

Background and objectives: The purpose of this study was to compare the endotracheal tube cuff pressure changes during laparoscopic surgeries using air versus nitrous-oxide in anesthetic gas mixture; and to observe the incidences of postoperative sore throat, hoarseness and dysphagia. Methods: Total 100 patients scheduled for elective laparoscopic abdominal surgery were allocated into two groups. Group A (n =50) received air white Group N (n=50) received nitrous-oxide in anesthetic gas mixture. After endotracheal intubation, cuff was inflated with air to achieve sealing pressure. Cuff pressure at baseline (sealing pressure), 30 min, 60 min and 90 min was recorded with a manometer. Incidence of sore throat, hoarseness and dysphagia was noted at the time of discharge from post-anesthesia care unit and 24 h after extubation. Results: Cuff pressure increased from baseline in both the groups. The increase in cuff pressure in Group N was greater than that in Group A at all time points studied (p < 0.001). Within Group A, cuff pressure increased more at 90 min than at 30 min (p < 0.05). Within Group N, increase in cuff pressure was more at each time point (30, 60 and 90 min) than its previous time point (p < 0.05). The incidence of sore throat in post-anesthesia care unit was higher in Group N than in Group A. Conclusion: Use of nitrous-oxide during laparoscopy increases cuff pressure resulting in increased incidence of postoperative sore throat. Cuff pressure should be monitored routinely during laparoscopy with nitrous oxide anesthesia. (C) 2018 Sociedade Brasileira de Anestesiologia. Published by Elsevier Editora Ltda.