Transversus Abdominis Plane Block Reduces Intraoperative Opioid Consumption in Patients Undergoing Periacetabular Osteotomy

Background: Administering intraoperative analgesia in patients undergoing periacetabular osteotomy (PAO) is challenging due to both the relevant surgical approach and osteotomies, which are associated with pain. The aim of this study was to assess the effect of the transversus abdominis plane block (TAPb) on intraoperative opioid consumption and circulation parameters in PAO patients. Patients and Methods: We conducted a two-group randomized-controlled trial involving 42 consecutive patients undergoing PAO for symptomatic developmental dysplasia of the hip (DDH) in our department. Patients assigned to the study group received an ultrasound-guided TAPb with 0.75% ropivacaine before the beginning of the surgery and after general anesthesia induction. Patients assigned to the control group did not receive a TAPb. General anesthesia was conducted according to a defined study protocol. The primary endpoint of the study was the intraoperative opioid consumption, measured in morphine equivalent dose (MED). Secondary endpoints were the assessment of intraoperative heart rate, mean arterial pressure (MAP), need for hypotension treatment, and length of hospital stay (LOHS). A total of 41 patients (n = 21 TAPb group, n = 20 control group) completed the study; of these, 33 were women (88.5%) and 8 were men (19.5%). The mean age at the time of surgery was 28 years (18-43, SD +/- 7.4). All operations were performed by a single high-volume surgeon and all TAPb procedures were performed by a single experienced senior anesthesiologist. Results: We observed a significantly lower intraoperative opioid consumption in the TAPb group compared to the control group (930 vs. 1186 MED per kg bodyweight; p = 0.016). No significant differences were observed in the secondary outcome parameters. We observed no perioperative complications. Conclusion: Ultrasound-guided TAPb significantly reduces intraoperative opioid consumption in patients undergoing PAO.