Postoperative Analgesia in Neonates and Infants Using Epidural Chloroprocaine and Clonidine

INTRODUCTION: In neonates and infants, epidural analgesia has gained popularity as a means of providing postoperative analgesia, limiting opioid-related adverse effects and improving the postoperative course. In addition to a local anesthetic agent, adjunctive agents may be added to further augment analgesia. Clonidine is an α(2)-adrenergic agonist that is frequently added to single-shot caudal analgesia, but there are limited data regarding its use in a continuous epidural infusion, especially in patients ≤12 months of age. METHODS: We retrospectively reviewed the hospital records of neonates and infants who received postoperative epidural infusions with 2-chloroprocaine, and clonidine was identified over a 4-year period. RESULTS: The study cohort included 52 neonates and infants ranging in age from 0 to 12 months and in weight from 2.1 to 10.1 kilograms. The catheters were dosed with either 1.5% 2-chloroprocaine (n=47) or 3% 2-chloroprocaine (n=5) with clonidine (median concentration 0.2 µg/mL) infused at a median rate of 0.72 mL/kg/hour. Pain scores were uniformly ≤3 at all evaluation points during the first 72 postoperative hours with a limited need for supplemental systemic opioids. No serious adverse effects were noted. CONCLUSION: With the recognized limitations of a retrospective study, these preliminary data demonstrate the safety of adding clonidine to an epidural infusion of 2-chloroprocaine in neonates and infants less than 12 months of age. Future studies are needed to determine its analgesic efficacy compared to 2-chloroprocaine alone and the optimal clonidine concentration for postoperative epidural infusions.