Introduction: Previous reports note that the use of regional anesthesia through continuous wound perfusion with bupivacaine reduces postoperative narcotic usage. We designed a study to examine the effectiveness of continuous local anesthetic on postoperative pain, days until first post operative bowel movement and days until hospital discharge.
Methods: We undertook a randomized, prospective, blinded study with 30 patients undergoing laparotomy receiving either 0.5% bupivacaine or saline infused continuously in the incision site. The primary outcome measure was morphine sulfate usage for up to 7 days after the initial operation. Secondary outcome measures were post operative days until first bowel movement and the total number of hospital days required until discharge.
Results: The control group with continuous saline in the implantation device required a mean of 119mg of morphine sulfate, 2.7 days until first post operative bowel movement and a mean of 8.0 hospital days from admission until discharge. The bupivacaine group required a mean of 154mg of morphine sulfate, 2.8 days until first post operative bowel movement and a mean of 7.0 hospital days from admission until discharge. In each instance significance was not reached by the Student T-test
Conclusion: This study indicates no reduction in patient morphine sulfate usage was noted by continuous infusion of 0.5% bupivacaine compared with infusion of normal saline. Also not affected by use of 0.5% bupivacaine infusion were days until first bowel movement and total hospital days until discharge. The use of devices that infuse local anesthetic into the wound site after laparotomy are of questionable value.