Neonatal neurobehavior in the first 48 hours of life: effect of the administration of meperidine with and without naloxone in the mother.

The early neonatal neurobehavioral scale was administered to three groups of newborns at 2, 4, and 24 hours of age. Group 1 consisted of 28 babies whose mothers had received no narcotics during labor, group 2 of 33 babies whose mothers had received meperidine hydrochloride alone during labor, and group 3 of 40 babies whose mothers had received meperidine followed by 0.4 mg of naloxone hydrochloride intravenously approximately 15 minutes before delivery. Babies who were not exposed to meperidine showed a statistically significantly greater percentage of high scores than those exposed to meperidine alone for all items on the neurobehavioral scale at 2 and 4 hours and for all items except tone and Moro response at 24 hours. Similarly, babies whose mothers had received meperidine and naloxone showed a significantly greater percentage of high scores than those whose mothers had received meperidine alone at 2 hours of age. At 4 hours a difference was found for tone and rooting and at 24 hours for overall score, placing, and total decrement score. It is concluded that naloxone given intravenously to the mother reverses the effect of meperidine on neonatal neurobehavior for approximately two hours after birth. At 4 and 24 hours, however, the neurobehavior of neonates exposed to meperidine and naloxone is depressed almost as much as that of babies exposed to meperidine alone.