Inflation of tapered cuff with 10 mL air for tracheal intubation : An in vitro study

Abstract

Optimal cuff pressure is essential to avoid aspiration after tracheal intubation. In rapid sequence induction, one cuff filling method is to inject a fixed volume of 10 mL air and adjust immediately afterwards. However, this does not always ensure adequate initial cuff pressure. The aim of this study was to evaluate the initial cuff pressure of tapered-cuff tracheal tubes after injection of 10 mL air in vitro. For tracheal models with internal diameters(i.d.)of 18 mm, 19 mm, and 20 mm, the initial cuff pressure of the tapered-cuff tracheal tubes(i.d. 7.0 mm and 8.0 mm)exceeded 99 cmH₂O after injection of 10 mL air. For the tracheal model with i.d. of 22 mm, cuff pressures were 57±7.8 cmH₂O(i.d. 7.0 mm)and, 69.7±5.1 cmH₂O(i.d. 8.0 mm). All studied combinations showed considerably higher pressure than the ideal value of 25 cmH₂O. For tapered cuff, 10 mL air might be excessive.