IntroductionUltrasound guided caudal epidural block (CEB) and transversus abdominis plane block (TAPB) are two techniques which are used for pain management after inguinal hernia surgeries (IHR). CEB is accepted as gold standard for lower abdominal surgeries while TAPB is more popular.ObjectiveIt is aimed to compare ultrasound guided CEB and TAPB for postoperative pain scores, additional analgesic requirement and chronic pain development in pediatric bilateral open IHR.Study designSeventy patients aged 1-7 years undergoing bilateral open IHR were included in this prospective, randomized, double-blinded study. Patients were randomized into group T (Bilateral TAPB) and group C (CEB). Postoperative FLACC (Face, Legs, Activity, Cry, Consolability) scores were evaluated for pain density. Additional analgesic requirement, length of hospital stay was also recorded. Chronic pain is evaluated within a subgroup by using "revised Bieri faces pain scale" in the postoperative second month.ResultsPostoperative 15th, 30th, 45th min, first, second hour FLACC scores were similar in both groups (P > 0.05). In group C, FLACC scores at post-operative sixth and 24th were significantly higher than group T (1 (0-5) vs 0 (0-2); 1 (0-3) vs 0 (0-2), respectively; P < 0.001). Additional analgesic requirement in the postoperative 24 h was found to be statistically higher in Group C (56.7%) than in Group T (20%) (P < 0.01). Chronic pain development did not differ between the groups (P > 0.05). Length of hospital stay was found to be shorter in patients in Group T compared to patients in Group C [10 (5-14) vs 16 (5-18) hours, respectively; P < 0.01)].DiscussionOur results exhibited that TAPB and CEB for bilateral IHR have similar early analgesic efficacy in children. However; CEB patients experienced higher FLACC scores at the postoperative sixth and 24th hours, and the need for additional analgesics was higher and the length of hospital stay was longer comparing to TAPB. Of note, chronic pain was not observed in any of our subgroup patients (n Z 21) who are older than four years.ConclusionFor bilateral IHR, US-guided CEB and TAPB have similar analgesic efficacy in the first six hours, postoperatively, However, TAPB appears to be slightly superior than CEB in terms of subacute pain and length of stay which is still not clinically distinctive.