Clonidine in preterm-infant caudal anesthesia may be responsible for postoperative apnea.

Abstract

Regional anesthesia without adjunctive general anesthesia or sedation has been recommended for preterm infants to decrease the risk of postoperative apnea. Single-dose caudal local anesthetic has a limited duration, which may be insufficient for long surgery. Addition of clonidine to local anesthetics has been shown to prolong the duration of surgical analgesia. However, respiratory depression related to clonidine may occur in adults. Respiratory depression has not been reported after caudal administration of clonidine in preterm infants. Here we report a case of early postoperative apnea in a waking preterm infant after caudal anesthesia performed with lidocaine, bupivacaine, and clonidine. A male infant, 39 postconceptual weeks old, was administered a single-injection caudal anesthesia without sedation with 5 mg/kg lidocaine plus 2.5 mg/kg bupivacaine and 1.25 microg/kg clonidine for bilateral inguinal hernia repair, and had early postoperative apneic events. Except for gestational age, the patient showed no apparent risk factors for postoperative apnea. The infant was monitored 24 hours in a neonatal intensive care unit, and no other apnea was recorded. Our report suggests that clonidine may be responsible for postoperative apnea in a preterm neonate. Further studies are required to determine the useful safe dose of clonidine for single-injection caudal anesthesia in those infants.