Comparison of bilateral ilioinguinal-iliohypogastric nerve block versus transverses abdominis nerve block for postoperative pain management for parturient undergoing elective cesarean section in Dilla University Referral Hospital, Ethiopia. A randomized controlled trial

ABSTRACT Background: Pain is one of the most common complaints and causes of distress in the perioperative period. The postoperative pain after cesarean section is believed to be of mild to moderate intensity lasting for up to 72 h. Apart from patient preferences, several factors affect choices of analgesia in a resource-limited setting like Ethiopia. Availability of resources, trained manpower, and inter-individual variation in pain threshold was among the factors affecting analgesia choices. Thus, this study aims to compare TAP block versus II/IH block for post-cesarean delivery analgesia in resource-limited areas where the ultrasound-guided block is not practiced. Method: A randomized controlled trial study was conducted in Dilla university referral hospital. Pregnant women scheduled for elective cesarean section were randomized to either TAP block (n = 36) or II/IH block (n = 36) for postoperative pain management. The sample size was calculated using a G-power version 3.1.9.2 getting a total of 72 participants. Pain severity, total tramadol consumption, and time to first analgesic request were assessed during the first 72 h postoperatively. Manny Whitney U -test and independent t -test were used based on the distribution of data. A Kaplan Meier analysis was used to assess' proportion of patients who did not require analgesia for a 48 h follow up period. Result: The cumulative median tramadol consumption over 48 h were 100 mg for TAP group and 150 mg for II/IH (p = 0.018). The median tramadol consumption at 24hr. and 36 h were also lower in the TAP group compared to II-IH (P < 0.05). There was no statistically significant difference between groups regarding time to first analgesia request (p > 0.05). The median pain score at 36hr. and 48hr. were lower in the TAP group (3 and 4) compared to the II-IH group (4 and 6) respectively (p < 0.05). There is no statistically significant difference between groups regarding the postoperative side effects and complications. Conclusion: Both II-IH and TAP block had comparable analgesic efficacy during the first 24hr. TAP block had longer analgesic effectiveness compared to II-IH with an effect lasting for 48hr. Highlights: