A triple‐blind, placebo‐controlled randomised trial of the ilioinguinal‐transversus abdominis plane (I‐TAP) nerve block for elective caesarean section

Abstract

This study investigated the efficacy of a new ilioinguinal-transversus abdominis plane block when used as a component of multimodal analgesia. We conducted a prospective, triple-blind, placebo-controlled randomised study of 100 women undergoing elective caesarean section. All women had spinal anaesthesia with hyperbaric bupivacaine, 15 μg fentanyl and 150 μg morphine, as well as 100 mg diclofenac and 1.5 g paracetamol rectally. Women were randomly allocated to receive the ilioinguinal-transversus abdominis plane block or a sham block at the end of surgery. The primary outcome was the difference in fentanyl patient-controlled analgesia dose at 24 h. Secondary outcomes included postoperative pain scores, adverse effects and maternal satisfaction. The cumulative mean (95%CI) fentanyl dose at 24 h was 71.9 (55.6-92.7) μg in the ilioinguinal-transversus abdominis group compared with 179.1 (138.5-231.4) μg in the control group (p < 0.001). Visual analogue scale pain scores averaged across time-points were 1.9 (1.5-2.3) mm vs. 5.0 (4.3-5.9) mm (p = 0.006) at rest, and 4.7 (4.1-5.5) mm vs. 11.3 (9.9-13.0) mm (p = 0.001) on movement, respectively. Post-hoc analysis showed that the ilioinguinal-transversus abdominis group was less likely to use ≥ 1000 μg fentanyl compared with the control group (2% vs. 16%; p = 0.016). There were no differences in opioid-related side-effects or maternal satisfaction with analgesia. The addition of the ilioinguinal-transversus abdominis plane block provides superior analgesia to our usual multimodal analgesic regimen.

A review of peripheral nerve blocks for cesarean delivery analgesia

“…It also reduced pain scores at rest and with movement in the first 24 hours postoperatively 48. There was no difference in sedation, nausea, vomiting, or pruritus between the groups; however, there was one report of a femoral nerve palsy after II-IH nerve blockade 48. While more evidence is needed before IH-II blocks can be recommended as a reliable technique for cesarean delivery analgesia, the availability of other peripheral blocks with a greater degree of dermatomal spread (and potential visceral effect) suggests that research time and effort are better spent in other areas.…”

“…In a prospective, triple-blind, placebo-controlled randomized trial, the combined I-TAP demonstrated reduced opioid use compared with placebo at all time points. It also reduced pain scores at rest and with movement in the first 24 hours postoperatively 48. There was no difference in sedation, nausea, vomiting, or pruritus between the groups; however, there was one report of a femoral nerve palsy after II-IH nerve blockade 48.…”

“…Other investigators have compared TAP versus II-IH47 blocks as well as combined II-TAP (I-TAP) blocks 48. In one study, TAP showed reduced tramadol consumption compared with II-IH blocks after cesarean delivery with spinal anesthesia that did not include ITM 47.…”

“…Patients with failed blocks were excluded from this study, making the conclusions more robust. The I-TAP block combines the compartment block of TAP with the specific nerves of the II-IH block, thereby providing more reliable coverage of the L1 dermatome that is often lost by TAP alone (TAP block is estimated to fail in provision of L1 sensory block in >50% of patients) 48. In a prospective, triple-blind, placebo-controlled randomized trial, the combined I-TAP demonstrated reduced opioid use compared with placebo at all time points.…”

Postoperative Analgesic Effectiveness of Quadratus Lumborum Block for Cesarean Delivery under Spinal Anesthesia

“…53 Several other abdominal wall blocks have also been proposed for cesarean delivery, including the transverse abdominis plane blocks, 54 erector spinae plane block, 55,56 and the iliohypogastric and ilioinguinal nerve blocks. 57,58 However, multimodal analgesia inclusive of spinal PAIN MEDICINE morphine is a strong analgesic that may mitigate the need for any additional interventions. Indeed, this has been previously demonstrated for transversus abdominis plane block, which, when used as a part of a multimodal regimen inclusive of spinal morphine, does not add any analgesic benefits.…”