Intraperitoneal lidocaine for decreasing intra-operative pain during postpartum tubal resection in Srinagarind Hospital.

Objective: To evaluate the effectiveness and determine the minimal dosage of intraperitoneal lidocaine for pain relief during postpartum tubal resection in Srinagarind Hospital.

Material And Method: Sixty postpartum women, undergoing postpartum tubal resection performed by residents at the Department of obstetrics and gynecologic, were included in this randomized, double-blinded, placebo controlled study. They were randomly assigned to one of three groups. They all received 20 ml solution intraperitoneally. Group one received it as isotonic normal saline; group 2 received it with 100 mg of lidocaine; and group 3 received it with 200 mg of lidocaine. The intra-operative and post-operative pain was measured by using a numerical rating score (NRS, from 0-10).

Results: The mean of intra-operative NRS in the lidocaine groups (100 and 200 mg) were significantly lower than the isotonic normal saline group (3.40, 3.50 vs. 6.55, p-value 0.019 and 0.024). No significant difference was found in the intra-operative NRS between 100 and 200 mg lidocaine (NRS 3.40 vs. 3.50, respectively, mean difference 95% CI -2.41 to 2.21). There was no significant difference in the immediate post-operative pain among these three groups (p-value 0.613).

Conclusion: Intraperitoneal lidocaine instillation provides effective intra-operative pain relief in postpartum tubal resection under local anesthesia. 100 mg of lidocaine is effective in pain relief This technique was not effective for relief of immediate post-operative pain.