Laryngeal masks vs. endotracheal tubes: Impact on atelectasis during general anesthesia

Laryngeal masks are more effective than endotracheal tubes in reducing lung ultrasound scores and improving oxygenation during general anesthesia.

The aim was to gauge the effect of laryngeal masks versus endotracheal tubes on atelectasis during anesthesia induction via lung ultrasound (LUS) and guide respiratory care.

This single-center, double-blind, randomized controlled trial was executed in the operating room and post-anesthesia care unit. The follow-up evaluations were accomplished in the ward. It involved 180 patients undergoing non-laparoscopic surgeries in urology, gynecology, and orthopedic limb procedures. Participants were randomized to either the endotracheal intubation or laryngeal mask group. Measurement of LUS scores was done across 12 lung regions at baseline, 15 minutes after airway placement, at the end of surgery, and 30 minutes after airway removal.

Other parameters were also evaluated like dynamic lung compliance, occurrence of post-surgery lung complications, throat pain, oxygenation index, and other complications at 24 and 48 hours after surgery. LUS score in all twelve lung regions at fifteen minutes following airway establishment was the key endpoint ascertained.

In the intention-to-treat (ITT) assessment of 177 volunteers, endotracheal intubation elicited substantially greater LUS scores at fifteen minutes (P < 0.001, mean difference 4.15 ± 0.60, 95% CI [2.97, 5.33]), end of surgery (P < 0.001, mean difference 3.37 ± 0.68, 95% CI [2.02, 4.72]), and thirty minutes after removal (P < 0.001, mean difference 2.63 ± 0.48, 95% CI [1.68, 3.58]). No major complications were witnessed in either group.

Laryngeal masks were found to be more beneficial than endotracheal intubation in minimizing atelectasis during urological non-laparoscopic, orthopedic limb, and gynecological surgeries. But, these outcomes may not apply to surgeries having an escalated risk of laryngeal mask leakage or in obese individuals. The effectiveness of laryngeal masks in alleviating postoperative atelectasis also remains unclear when muscle relaxation and reversal therapy are comprehensively monitored.