Comparison of postoperative pain scores following bilateral erector spinae versus bilateral transversus abdominis plane blocks in parturients undergoing elective caesarean delivery under spinal anaesthesia at the Aga Khan University hospital, Nairobi
Date of Award
Master of Medicine (MMed)
Dr. Rajpreet Bal
Dr. David Odaba
Professor Wangari Waweru-Siika
Anaesthesiology (East Africa)
BACKGROUND: Good pain control following lower segment caesarean section (LSCS) is essential to facilitate early mobilization and to enable adequate care of the new-born by the mother. Inadequate analgesia after caesarean delivery has been associated with increased incidences of deep venous thrombosis, chronic pain, greater opioid use and postpartum depression. Peripheral or trunk nerve blocks have become popular as part of a multimodal approach, together with opioids and non-steroidal analgesics, in controlling post caesarean pain. While the transversus abdominis plane (TAP) block has emerged in recent years as the most widely performed block for post caesarean pain the novel erector spinae plane (ESP) block is easier to perform and is just as effective.
OBJECTIVES: The primary objective of this study was to compare postoperative pain scores following a bilateral erector spinae plane block versus a bilateral transversus abdominis plane block in parturients undergoing LSCS under spinal anaesthesia. Secondary objectives were to determine time to first morphine use and the total morphine consumption between the two groups over the first 48hrs post operatively.
METHODS: this was a single-centre, randomized, non-inferiority trial. Forty parturients were randomly assigned to receive either a TAP or ESP block with 20mls of 0.25% bupivacaine + 1: 200,000 adrenaline bilaterally at the end of surgery. The primary outcome was the mean visual analog scale (VAS) pain scores at 2, 6, 12, 24 and 48 hours postoperatively. The non-inferiority margin was set at 1 centimeter VAS score. Time to first morphine use and total morphine consumption were also assessed.
RESULTS: Forty patients were randomized 20 in each arm. The mean treatment difference (ESP - TAP) at 24 hours was 0.2cm (-0.06-0.87). The upper margin of the 95% confidence interval (0.87) not exceeding the non-inferiority margin of 1cm. There was no significant difference between the two groups in terms of time to first morphine dose, 195.78 minutes (144.36) in the ESP group versus 185 minutes (67.50) in the TAP group p-value 0.7838. There was no statistically significant difference in the total morphine consumption over 48 hours between the two groups as well, 16.11 (7.42) ESP versus 14.63 (7.03) TAP, p-value 0.5334.
CONCLUSION: In this study, the ESP block was non-inferior to TAP block in the management of post caesarean pain in a multimodal regime but only after 12 hours to 48 hours postoperatively. Considering the local anesthesia effects may be minimal during this latter time these results are inconclusive and non-inferiority of erector spinae block compared to TAP block cannot be concluded.
Thuranira, R. (2021). Comparison of postoperative pain scores following bilateral erector spinae versus bilateral transversus abdominis plane blocks in parturients undergoing elective caesarean delivery under spinal anaesthesia at the Aga Khan University hospital, Nairobi (Unpublished master's dissertation). Aga Khan University, East Africa.