Comparison of the Effects of Indomethacin, Diclofenac and Acetaminophen Suppositories on Pain Score and Pethidine Usage after Cesarean Section

Background: Cesarean section is one of the common surgeries among women with a current rate of 14-15% in western societies. However, the rates are much higher in Iran. Acute postoperative pain is one of the recognized complications after cesarean section. Uncontrolled postoperative pain may interfere with breast-feeding. It might also affect the emotional relation between newborn and mother. This study was designed to compare the effects of indomethacin, diclofenac sodium, and acetaminophen suppositories on opioid usage after cesarean section in Alavi Hospital, Ardabil, Iran. Methods: In this triple-blind clinical trial, 120 ASA I-II candidates of cesarean with spinal anesthesia were randomly divided into 4 groups of 30. Acetaminophen, indomethacin, and diclofenac were used after the operation in the first, second, and third groups, respectively. The dosage was repeated every 6 hours and opioid usage was compared during the first 24 hours after the surgery. The fourth group was considered as the control group and received placebo suppository. Opioid was also used when required (PRN). The severity of pain was recorded based on a visual analogue scale (VAS). In case of severe pain (VAS > 5), 0.5 mg/kg intramuscular pethidine was prescribed. The data was analyzed in SPSS using analytical statistics such as analysis of variance (ANOVA), chi-square test and Tukey's post hoc test. Findings: There were no statistically significant differences between the groups in baseline data. There were statistically significant differences between the control group and other groups in pain scores 1, 12, and 24 hours after the operation. Groups receiving acetaminophen and nonsteroidal anti-inflammatory drugs (NSAIDs), i.e. indomethacin and diclofenac, were significantly different in pain scores 12 and 24 hours after the operation. The three intervention groups received the first dose of pethidine much later than the control group and the distance for both NSAIDs (diclofenac and indomethacin) was significantly longer (P < 0.001). Indomethacin, diclofenac, and acetaminophen significantly reduced the amount of pethidine usage during the first 24 hours after the surgery compared to the control group. This reduction was more in indomethacin and diclofenac groups compared to acetaminophen group (P = 0.001). Conclusion: Considering the significant reduction in pain scores and opioid usage especially in indomethacin and diclofenac groups in comparison with the control group, it is suggested to prescribe indomethacin and diclofenac for post cesarean section analgesia. Keywords: Cesarean section, Indomethacin, Diclofenac, Acetaminophen, Opioid