A randomised comparison of transverse abdominal plane block versus thoracic epidural analgesia on postoperative opioid consumption for colorectal enhanced recovery after surgery programme (OPIATE study).

Abstract

The transverse abdominis plane block is increasingly being used as a less-invasive alternative to thoracic epidural analgesia for effective pain management. This study aimed to compare transverse abdominis plane block with opioid-based thoracic epidural analgesia in terms of postoperative opioid consumption. Patients in the thoracic epidural analgesia group received a continuous infusion of 0.1% levobupivacaine with 2mcg/ml of fentanyl, while those in the transverse abdominis plane group received 6-hourly boluses of 0.4ml/kg of 0.25% levobupivacaine. The primary objective was to compare the average fentanyl consumption, measured as intravenous fentanyl equivalents, over 72 hours. Data of 35 patients were analysed. Fentanyl consumption at the end of 72 hours was significantly lower in the transverse abdominis plane group (median [interquartile range] 495 mcg (255, 750), and mean (95% confidence interval) 717.35mcg (403.54-1031.16)) compared to the thoracic epidural analgesia group (median [interquartile range] 760mcg (750, 760), and mean (95% confidence interval) 787mcg (746.81-827.19)) with a p value of 0.010. Pain scores at rest and during movement were comparable between the groups (p > 0.05). However, the median pain scores during movement were significantly lower in the thoracic epidural analgesia group at 60 and 72 hours (p ⩽ 0.05). Multimodal analgesia with transverse abdominis plane resulted in lower opioid consumption over 72 hours compared to thoracic epidural analgesia.