Comparison of the effects of transversus thoracic muscle plane block and pecto-intercostal fascial block on postoperative opioid consumption in patients undergoing open cardiac surgery: a prospective randomized study

Abstract Background There is an association exists between cardiac surgery, performed through median sternotomy, and a considerable postoperative pain. Objectives The aim of the current study is to compare the effects of transversus thoracic muscle plane block (TTMPB) and pecto-intercostal fascial plane block (PIFB) upon postoperative opioid consumption among the patients who underwent open cardiac surgery. Methods The present prospective, randomized, comparative study was conducted among 80 patients who underwent elective on-pump cardiac surgery with sternotomy. The subjects were randomly assigned to two groups with each group containing 40 individuals. For the TTMPB group, bilateral ultrasound-guided TTMPB was adopted in which 20 ml of 0.25% bupivacaine was used on each side. In case of PIFB group, bilateral ultrasound-guided PIFB was adopted with the application of 20 ml of 0.25% bupivacaine on each side. The researchers recorded the first time for rescue analgesia, the overall dosage of rescue analgesia administered in the first 24 h after the operation and the postoperative complications. Results The PIFB group took significantly longer time to raise the first request for rescue analgesia (7.8 ± 1.7 h) than the TTMPB group (6.7 ± 1.4 h). Likewise, the PIFB group subjects had a remarkably lower ‘overall morphine usage’ in the first 24 h after the operation (4.8 ± 1.0 mg) than TTMPB group (7.8 ± 2.0 mg). Conclusion Bilateral ultrasound-guided PIFB provided a longer time for the first analgesic demand than bilateral ultrasound-guided TTMPB in patients undergoing open cardiac surgery. In addition to this, the PIFB reported less postoperative morphine usage than the TTMPB and increases satisfaction in these patients. Trial registration This study was registered at Clinical Trials.gov on 28/11/2022 (registration number: NCT05627869).