Efficacy of ultrasound-guided transversus abdominis plane block versus epidural analgesia in pain management following lower abdominal surgery

Abstract

Objective Transversus abdominis plane (TAP) block is a new, rapidly expanding technique. This study was designed to evaluate the efficacy of ultrasound-guided TAP block in comparison with epidural analgesia in pain management following lower abdominal surgery. Setting and duration The present study was conducted on 60 patients aged 20-75 years, who were admitted at Al-Azhar University Hospitals from February 2013 to March 2014. Patients and methods These patients were allocated to either group I (TAP, 30 cases) or group II (epidural block, 30 cases) using a randomized central computer-generated sequence held by an investigator not involved with the clinical management or data collection. The primary outcome was the proportion of participants who used more than 200 mg/kg of morphine in the first 24 h on arrival at the recovery ward. Secondary outcomes included the following: morphine consumption 24 h after operation; pain measured using the visual analog score in the recovery ward and at 2, 6, 10, 14, 18, and 24 h after operation; and postoperative nausea and vomiting measured with the total number of vomits during the first 24 h. Results The most important finding in our study was that TAP block provided highly effective postoperative analgesia in the first 24 h, especially in the neurofascial plane in the muscles and the skin but not the visceral pain, and that the TAP block reduced the mean intravenous morphine requirements by more than 70%. This reduction in opioid requirement resulted in fewer opioid side effects. In the present study, there was no significant difference between the studied groups as regards time spent in the recovery room, need for paracetamol during the first 8 h after surgical intervention, postoperative nausea and vomiting, and duration of hospital stay. In contrast, the total morphine consumption during the first 8 h was significantly less in group I than in group II, and the time to first analgesic request was significantly longer in group I than in group II. Finally, the number of cases that required more than 200 mg of morphine during the first 24 h was significantly less in group I than in group II. Conclusion Ultrasound-guided TAP block is an effective alternative for providing postoperative analgesia after lower abdominal surgery in comparison with epidural analgesia, but further studies in larger population are necessary.