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.

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).