Bupivacaine wound instillation via an electronic patient-controlled analgesia device and a double-catheter system does not decrease postoperative pain or opioid requirements after major abdominal surgery

To assess the analgesic efficacy of patient-controlled bupivacaine wound in stillation, 50 patients undergoing major intraabdominal surgery were enroll ed into this prospective, placebo-controlled, double-blinded study. In all cases, a standard general anesthetic was administered. On completion of sur gery, two multihole 20-gauge epidural catheters were tunneled through the p roximal and distal apices of the surgical wound and placed above the fascia such that the tips were at the margin of the first and second thirds of th e surgical wound, respectively. Postoperatively, a patient-controlled analg esia (PCA) device was connected to the instillation system. Either bupivaca ine 0.25% (Bupivacaine Group) or an equal volume of sterile water (Control Group) was administered. The PCA device was programmed to deliver 9.0 mt wi th a Ga-min lockout interval and no basal infusion. During the first six po stoperative hours, a coinvestigator administered "rescue" morphine (2 mg IV ). Thereafter, meperidine 1 mg/kg IM was administered on patient request fo r additional analgesia. Instillation attempts and actual number of injectio ns were similar between the groups. The mean number of pump infusions and t he mean "rescue" opioid requirements during the 24-h study period were simi lar between the groups. The total "rescue" morphine administered during the first six postoperative hours was 16 +/- 17 mg vs 18 +/- 14 mg for the Bup ivacaine and Control Groups, respectively. The total meperidine administere d during this period was 1.6 +/- 1.4 mg/kg and 2 +/- 1.2 mg/kg for the Bupi vacaine and Control Groups, respectively. Preoperatively, hourly for the fi rst six postoperative hours, and on removal of the instillation catheter, p atient-generated visual analog scales for pain were similar at rest, on cou ghing, and after leg raise. In conclusion, bupivacaine wound instillation v ia an electronic PCA device and a double-catheter system does not decrease postoperative opioid requirements after surgery performed through a midline incision.