Effect of wound infiltration with bupivacaine on postoperative analgesia in neonates and infants undergoing major abdominal surgery: a pilot randomized controlled trial.

PURPOSE: Postoperative pain management is essential in the perioperative care of neonates and infants but it requires a high level of care. Wound infiltration with bupivacaine, a long-acting local anesthetic, is a simple method with minimal complications. However, studies on the effectiveness of wound infiltration in neonates and infants are lacking. The purpose of this study was to investigate the effectiveness of wound infiltration with bupivacaine for postoperative analgesia in neonates and infants undergoing abdominal surgery.

METHODS: A prospective, randomized controlled trial was conducted in 34 neonates and infants. The patients were randomized into two groups: the bupivacaine (B) group and the control (C) group. A standardized anesthetic protocol was used for each patient. Before wound closure, the surgical site of each patient in the B group was infiltrated with 2 mg/kg of bupivacaine, whereas no surgical site anesthetic infiltration was used in the C group. The neonatal infant pain scale (NIPS) score was used to evaluate postoperative pain, and fentanyl 0.5-1.5 μg/kg was administered when the NIPS score was ≥4. In regard to the fentanyl requirement, the NIPS score and the numbers of patients whose NIPS score was ≥4 were compared between the two groups.

RESULTS: The median fentanyl dose requirements in the B group and C group were 1 and 0.5 μg/kg, respectively; and the difference was not statistically significant (p = 0.255). The postoperative NIPS scores in the two groups were not significantly different. In addition, there were no significant differences in the numbers of patients whose NIPS score was ≥4 at 6, 12, 18, and 24 h postoperatively.

CONCLUSIONS: In neonates and infants, wound infiltration with bupivacaine had no significant effect on pain relief or fentanyl requirement during the first 24 h after major abdominal surgery.