Ultrasound-guided transversus abdominis plane blocks for analgesia post cesarean section

Sara MC Kelly¹, Rajiv K Malhotra^2
1Department of Anesthetics, Russell's Hall Hospital, Dudley, UK; ²Department of Anesthetics, Liverpool Women's Hospital, Liverpool, UK

Introduction: Cesarean section is a commonly performed operation and postoperative analgesia is needed so the mother can bond and look after her newborn. Transversus abdominis plane (TAP) blocks have been shown to improve postoperative analgesia in laparoscopic cholecystectomy and hysterectomies. The purpose of this article is to review the evidence for the use of TAP blocks in cesarean sections.
Methods: A literature search identified four randomized controlled trials that looked at the use of TAP blocks in cesarean section. Copies were obtained and critically appraised.
Results: Four randomized controlled trials were found that looked at the use of TAP blocks in cesarean sections. Two studies showed that TAP blocks reduced the postoperative analgesic requirements of patients compared to a placebo; one paper showed no difference when TAP blocks were used. In a study comparing TAP blocks with subarachnoid morphine, TAP blocks were associated with poorer postoperative pain scores and higher rescue analgesia. There was no consistent local anesthetic dose used amongst the trials. None of the studies revealed any statistically significant side effects from TAP blocks.
Discussion: TAP blocks have been shown to offer improved pain relief after cesarean sections when compared to a placebo, but have been shown to be inferior to subarachnoid morphine. Standardization of local anesthetic and dosage may result in an improved evidence base from which to draw clinically relevant conclusions.

Keywords: TAP block, cesarean section, regional anesthesia