Effect of neck position on endotracheal tube location in low birth weight infants.

Neck position can affect the position of the tip of the endotracheal tube (ETT) in normal neonates; this has not been systematically investigated in low birth weight (LBW) neonates. It was our intention to determine the effect of neck flexion and extension on ETT position in LBW infants. Eight LBW orotracheally-intubated infants underwent postmortem anteroposterior chest radiographs with the neck in a neutral position, in 55 degrees flexion, and in 55 degrees extension. Measurements from the thoracic inlet to the ETT were obtained in each position. The ETT always moved caudad with neck flexion (P = 0.001) and cephalad with neck extension (P = 0.001). The mean extent of ETT displacement was 3.1 mm (SD, 1.7 mm) with neck flexion, and 7.4 mm (SD, 5.2 mm) with extension (P < 0.05). We conclude that in LBW infants: 1) the direction of ETT movement with neck flexion and extension is predictable and identical to that seen in term infants and children, and 2) neck flexion should not be a principal consideration in management of ETT location.