Comparison of ultrasound-guided transversalis fascia plane block and anterior quadratus lumborum block in patients undergoing caesarean delivery: a randomized study

BACKGROUND: Cesarean section is becoming increasingly common. Well-managed postoperative analgesia improves patient comfort while encouraging early ambulation and breastfeeding. The analgesic efficacy of transversalis facial plane block (TFPB) vs. anterior quadratus lumborum block (QLB) was compared in this study. METHODS: We analyzed the data of 49 pregnant women (gestation, ≥ 37weeks; age, 18–45years) scheduled for elective cesarean delivery (CD) under general anesthesia. They were randomly divided into TFPB and anterior QLB groups. All blocks were administered bilaterally with 25mL of 0.25% bupivacaine under ultrasound guidance prior to extubation. Postoperative morphine consumption and numerical rating scale (NRS) pain scores (static and dynamic [during coughing]) were recorded at 1, 3, 6, 9, 12, 18, and 24h. RESULTS: There was no difference in postoperative morphine consumption between the groups at the third, sixth, and ninth hours, but the anterior QLB group consumed less morphine at the 12th, 18th, and 24th hours. Except for the first hour, resting and dynamic NRS scores were comparable between the groups. The first-hour resting and dynamic NRS scores were lower in the TFPB group (resting NRS, anterior QLB group, median [interquartile range], 2 [2–3] vs. TFPB group, 2 [0–2], p = 0.046; dynamic NRS, anterior QLB group, median [interquartile range], 3 [2–4] vs. TFPB group 2 [0–3], p = 0.001). CONCLUSIONS: In patients undergoing CD, anterior QLB decreased morphine consumption in the late period (9–24h) compared to TFPB, while pain scores were similar between both groups. The reduction in morphine consumption was statistically significant, but not clinically significant.