Accuracy of Age-Based Formula to Predict the Size and Depth of Cuffed Oral Preformed Endotracheal Tubes in Children Undergoing Tonsillectomy.

Prediction of the size of cuffed preformed endotracheal tubes using the formula of Motoyama was accurate in most patients, except in thin patients (body mass index < -2 SD). The insertion depth of the tubes was mostly in the range of the age-based-formula to the bend-to-tip distance.