Comparative evaluation of continuous infusion versus programmed intermittent bolus techniques in erector spinae plane block in modified radical mastectomy - A preliminary randomised controlled trial.

Background and aims: Single-shot erector spinae plane block (ESPB) provides excellent analgesia in mastectomy in the immediate post-operative period but is not sufficient to maintain for prolonged duration. This study compares the efficacy of programmed intermittent bolus (PIB) versus continuous infusion (CI) techniques after ESPB by placing a catheter for mastectomy.

Methods: After ethical approval and patient consent, ESPB was performed at the T4 level in 50 patients with an initial bolus of 20 mL 0.375% ropivacaine and a catheter placed 30 min before surgery. In the postoperative period, they were randomised to Group I - intermittent bolus of 20 mL 0.2% ropivacaine every 4 h for 24 h and Group C - continuous infusion of 0.2% ropivacaine at 5 mL/h for 24 h. The primary outcome was the 24-h fentanyl consumption by patient-controlled analgesia device. Data was analysed using Stata 14.0.

Results: Group I patients had reduced post-operative fentanyl consumption {mean [standard deviation (SD)]: 166 (139.17) µg vs 332 (247.96) µg, P = 0.002} and lower median NRS scores (1 h: 3 vs 5), (2 h: 3 vs 5), (4 h: 3 vs 5), (6 h: 4 vs 5) with a higher mean (SD) Quality of Recovery-15 score {134.4 (8.53) vs 127 (12.89), P = 0.020} compared to Group C, respectively. The 24-h dermatomal sensory coverage was more comprehensive in Group I compared to Group C.

Conclusion: The PIB technique after ESPB provides decreased postoperative opioid consumption, better post-operative analgesia and quality of recovery compared to the CI technique in patients undergoing mastectomy.