Continuous wound infiltration with 0.2% ropivacaine versus a single intercostal nerve block with 0.75% ropivacaine for postoperative pain management after reconstructive surgery for microtia

Background and aim In reconstructive surgery for microtia during childhood, costal cartilage is used for pinna formation. Postoperative pain in the region from which the costal cartilage is taken is severe, which delays recovery after surgery. We evaluated prospectively whether continuous wound infiltration (CWI) of a local anesthetic (LA) reduces pain and enables rapid recovery compared with a single intercostal nerve block (ICNB). Method Forty-eight patients were randomly divided into two groups. In Group I, a single ICNB with 10 ml of 0.75% ropivacaine was performed at the end of surgery. In Group C, a catheter was inserted into the space between the abdominal external oblique muscle and the rectus abdominis muscle. Then, a 0.4-ml/kg bolus of 0.2% ropivacaine was administered, followed by continuous infusion at 2–4 ml/h for 48 h. Postoperative pain intensity evaluated using the Face Scale, dose of supplemental analgesics, and time until mobilization were evaluated. In Group C, the plasma concentrations of ropivacaine were analyzed. Results The pain intensity at rest was significantly lower in Group C than in Group I, but the values during coughing were comparable. The number of patients receiving a supplemental analgesic and the median number of doses were significantly larger in Group I than in Group C (P = 0.029, P = 0.0007, respectively). The plasma concentrations of ropivacaine were within the safe range over 48 h. The times until mobilization were comparable. Conclusion CWI of 0.2% ropivacaine is a better and safe technique for postoperative pain management after costal cartilage graft harvest in children.