Nasotracheal intubation in the neonate: physiologic responses and effects of atropine and pancuronium.

Thirty infants with birth weights from 580 to 3450 gm (25 to 40 weeks gestation) were prospectively studied during nasotracheal intubation. The infants were randomized to receive atropine 0.01 mg/kg, atropine 0.01 mg/kg plus pancuronium 0.1 mg/kg, or no medication (controls) prior to intubation. There was a significant decrease in transcutaneous PO2 (27.3 torr, P less than 0.02), associated with significant increases in mean arterial blood pressure (57%, P less than 0.01) and intracranial pressure (mean increase 18.9 cm H2O, P less than 0.01) with intubation in all three groups of infants. Only in control infants and infants receiving atropine was there significant decrease in heart rate (52.2 and 36.2 bpm, respectively, P less than 0.01) during intubation. Control infants experienced a significantly greater decrease in heart rate and demonstrated the lowest mean heart rate, compared with the other two groups. Pancuronium plus atropine was associated with lesser increases in intracranial pressure and with the least changes in heart rate in response to intubation. There was no significant difference between the groups for changes in systemic blood pressure or transcutaneous PO2. Further studies are required to determine the clinical consequences, if any, of these responses, and the use of pretreatment in the neonate requiring intubation.