Endotracheal tube orifice abutting the tracheal wall: a cause of infant airway obstruction.

Effects of endotracheal tube and infant head positions upon the orientation of the beveled tube orifice to the tracheal wall were studied in living infants receiving ventilatory assistance and in infant cadavers. Radiographs of infant cadavers showed that when the endotracheal tube orifice faces one direction and the infant's head faces the opposite direction, the tube orifice can abut the tracheal wall and thus obstruct the airway. This obstructive relationship was more readily produced with relatively high tube positions (above the level of T1) and/or with full neck flexion. Measurement of mean pulmonary resistance in living infants showed a position-dependent increase above the baseline of up to 487% (from 31 to 182 cm H2O/l/sec) when the tube orifice abutted the tracheal wall. The radiologist who observes the tube orifice against the tracheal wall should alert the clinician immediately so that endotracheal tube alignment can be adjusted to relieve obstruction.