Sniffing position combined with mouth opening improves facemask ventilation in children with adenotonsillar hypertrophy

摘要

Background: This study evaluates the influence of sniffing position combined with mouth opening on the effectiveness of facemask ventilation in paralyzed pediatric patients undergoing adenotonsillectomy during sevoflur-ane-N_2O anesthesia.Methods: After Institutional Ethics Committee approval, 40 children 5-11 years of age who were scheduled for an elective adenotonsillectomy operation were enrolled in this prospective randomized study. After routine monitoring and pre-oxygenation, anesthesia was induced with sevoflurane 8% in a mixture of 50% N_2O-O_2- Three minutes after the administration of vecuronium, the sequence of the positions was randomized. Three positions were applied during facemask ventilation: Position CN (closed mouth -neutral head and neck position), position CS (closed mouth-sniffing position) and position OS (opened mouth-sniffing position). Volume-controlled ventilation was started. Peak inspiratory pressure (PIP), tidal volume (V_T), expired tidal volume (V_Texp) and end-tidal CO_2 pressure were recorded. The percent of leakage was calculated. The primary endpoint of this study was the expired tidal volume (V_Texp).Results: There was a statistically significant difference among the three positions for V_Texp and PIP values. The OS resulted in higher V_Texp values when compared with CN (P = 0.022). The OS was significantly better than the other two positions, resulting in lower PIP values (P<0.001 and P = 0.004, for CN and CS, respectively). The OS also resulted in less leakage during facemask ventilation when compared with CN and CS. Conclusions: Sniffing position combined with mouth opening improves V_Texp and PIP values during facemask ventilation during sevoflurane-N_2O anesthesia in paralyzed pediatric patients with adenotonsillar hypertrophy.