Pancuronium and abnormal abdominal roentgenograms.

Pancuronium bromide treatment in severely ill, mechanically ventilated infants has been shown to result in lower peak transpulmonary pressure, with an accompanying lower-than-expected incidence of pneumothorax. Infants, treated with pancuronium often demonstrate an ominous abdominal roentgenographic finding: the "gasless abdomen." Of 38 mechanically ventilated infants, 22 of 24 pancuronium-treated infants (as compared with four of 14 untreated infants) had diminished or absent bowel gas. There was no significant difference between the two groups with regard to birth weight, mortality, or incidence of respiratory distress syndrome. Pancuronium prevents swallowing of air but does not inhibit gut peristalsis, thus accounting for the evacuation of abdominal gas three hours or more after administration of the drug. Clinicians who treat infants with pancuronium should be aware of the phenomenon, to avoid needless roentgenographic studies.