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

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 sevoflurane-N(2)O 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(2)O-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(2)O anesthesia in paralyzed pediatric patients with adenotonsillar hypertrophy.