Objective: We tested the hypothesis that local anesthetic that is injected before a vertical midline abdominal incision would decrease the use of postoperative opioids.
Study design: Patients who would undergo abdominal surgical procedures with general anesthesia by a planned vertical midline incision were enrolled in the study. Patients were assigned randomly to receive either 0.5% ropivacaine or normal saline solution placebo that was injected in the subcuticular tissue and fascia before the incision of each. All patients received morphine after the operation with a patient-controlled analgesia device. Morphine consumption was measured during the postoperative period at intervals of 0 to 6 hours, 6 to 12 hours, 12 to 24 hours, and 24 to 48 hours. Postoperative pain was assessed at 6, 12, 24, and 48 hours after the conclusion of the procedure with a visual analog scale.
Results: Eighty-four patients were enrolled in the study; 16 patients were excluded; therefore, 68 patients had useable data. The two treatment groups did not differ in age, height, weight, the length of the operation, the length of the incision, the position of the incision, the placement of drains, or the procedure that was performed. There was no significant difference in morphine consumption for any of the four intervals. The visual analog scale was not significantly different between the two groups at 6, 12, or 24 hours after operation. The visual analog scale at 48 hours was lower in the group that received ropivacaine (2.69 vs 4.26, P =.02). Data were analyzed by the Student t test.
Conclusion: Pre-emptive analgesia with 0.5% ropivacaine given before skin incision does not decrease the postoperative analgesic use in patients who undergo laparotomy by a midline vertical skin incision.