Objective: This study investigated the efficacy of bupivacaine wound infusion for pain control and opioid sparing effect after cesarean delivery.
Materials and methods: We conducted a randomized double blind, placebo controlled clinical trial on 60 parturients undergoing cesarean section at a university hospital in Tehran. Patients were randomized to receive a pump infusion system that was filled with either 0.25% bupivacaine or equal volume of distilled water. A catheter was placed above the fascia and connected to electronic pump for 24 hours. Postoperative analog pain scores and morphine consumption were assessed at 6, 12 and 24 hours. Also time interval to first ambulation, length of hospitalization, complications and patient satisfaction were recorded. Data were analyzed using the SPSS software and P < 0.05 was considered statistically significant. Mann-Whitney u-test, student t-test and chi-square were used.
Results: There were no differences in patient demographics and length of hospitalization and patient-generated resting pain scores between the two groups. Pain scores after coughing and leg raise during the first 6 postoperative hours were significantly less in the Bupivacaine group (P<0.001). The total dose of morphine consumption during the 24 hours study period was 2.5 ± 2.5 mg vs. 7.3 ± 2.7 mg for the bupivacaine and control groups, respectively (P<0.001). Compared with the control group, time to first ambulation was shorter in the bupivacaine group (11± 5h vs. 16 ± 4h) (P< 0.01).
Conclusion: Bupivacaine wound infusion was a simple and safe technique that provides effective analgesia and reduces morphine requirements after cesarean delivery.