Rao Kadam V, et al. – This randomized trial was performed to compare analgesia and cost–effectiveness between continuous transversus abdominis plane (TAP) block vs intermittent bolus. In abdominal surgery, continuous or bolus TAP blocks were effective analgesic techniques, with bolus technique being more economical.

• The authors recruited 20 American Society of Anesthesiologists ASA grade I to III patients undergoing elective abdominal surgery with 10 patients allocated to each arm after obtaining ethical approval.
• They performed bilateral ultrasound-guided TAP blocks with an initial bolus of 0.5% ropivacaine 20 mL per side, followed by catheter insertion.
• The continuous infusion group received 0.2% ropivacaine 8 mL/hour on each side and the intermittent bolus group received doses of 0.2% ropivacaine 20 mL per side every 8 hours for 48 hours after surgery.
• For this study, both groups received intravenous fentanyl patient-controlled analgesia and regular oral paracetamol.
• At baseline (time 0) and at 1 hour, 1 day and 2 days post-operatively, parameters recorded included numerical rating scores for pain and post-operative analgesic consumption.
• They also recorded the duration of catheter insertion, complications, patient satisfaction and information regarding costs.
• They assessed patient satisfaction utilizing a 4-point “Likert” scale on day 2 and on day 30.
• They examined pain and Likert scores by non-parametric sum rank test and all two-sampled t-tests assumed unequal variances.

• The authors found no difference between duration of TAP block, anesthetic and surgical technique and length of stay (p=0.23).
• Primary outcomes: at rest and cough, pain scores were not significantly different (p=0.20) between the groups.
• At day 2 and 30, satisfaction scores were similar (p=0.77).
• However, the bolus group was more cost-effective (AU$347.98 vs AU$429.43).