Gentle facemask ventilation during induction of anesthesia

摘要

Background: To determine the level of inspiratory pressure minimizing the risk of gastric insufflation while providing adequate pulmonary ventilation. Methods: In this prospective, randomized, double-blind study, patients were allocated to one of the two groups (P10, P15) defined by the inspiratory pressure applied during controlled -pressure ventilation: 10 and 15 cm H 2 O. Anesthesia was induced using propofol and sufentanil; no neuromuscular -blocking agent was administered. Once loss of eyelash reflex occurred, facemask ventilation was started for a 2 -min per- iod. The cross-sectional antral area was measured using ultrasonography before and after facemask ven- tilation. Respiratory parameters were recorded. Results: Forty patients were analyzed. Mean tidal volume was about 7 ml/kg in group P10, and was 11 ml/kg in group P15 in the same period. As indicated by ultrasonography test, the antral area in P15 group was markedly incresed compared with P10 group. Conclusion: Inspiratory pressure of 10 cm H 2 O allowed for reduced occurrence of gastric insufflation with proper lung ventilation during induction of anesthesia with sufentanil and propofol in nonparalyzed and nonobese patients.