Comparison of Transversus Abdominis Plane Block and IV Patient-Controlled Analgesia after Lower Abdominal Surgery

We aimed to compare the first 24-hour postoperative analgesic efficiency of ultrasound (USG)-assisted transversus abdominis plane (TAP) block to IV morphine patient-controlled analgesia (PCA) in patients undergoing lower abdominal surgery.

Fifty ASA I-III patients were included into this randomised, prospective clinical study. At end of surgery, Group 1 received 1 mg kg(-1) 0.5% bupivacaine and 1 mg kg(-1) 1% lidocaine in a 30-mL volume during TAP-block. Group 2 received 1 mg kg(-1) tramadol IV 10 minutes before extubation, and PCA was started with 1 mL morphine IV at a concentration of 1 mg kg(-1) and a 10-min lock time. Visual analogue scale (VAS), heart rate (HR), respiratory rate, peripheral oxygen saturation (SpO2), additional analgesic need and nausea-vomiting at the postoperative 30(th) minute and 1, 2, 3, 6, 12, and 24 hours were evaluated. In both groups, when VAS values were >4, patients were given 1 mg kg(-1) tramadol IV in first evaluation at the 30(th) minute or 15 mg kg(-1) paracetamol at other evaluations.

No difference was observed between groups in terms of VAS values. No difference was observed in terms of HR in the within-group comparison, but Group 1 HR values were lower compared to Group 2 (p<0.01). No difference was observed in additional analgesic need at any times. Nausea-vomiting score was higher in Group 2 in the between-group comparison at the 30(th) minute (p<0.04), but no difference was observed after the 1(st) hour.

Transversus abdominis plane block is effective as IV morphine-PCA in postoperative pain therapy in lower abdominal surgery, when given in a 30-mL volume. It may be preferable to IV-PCA, as the analgesic effect starts earlier and decreases the systemic effect of the morphine used in PCA.