Intraoperative thoracic interfascial plane block with levobupivacaine versus levobupivacaine with dexmedetomidine for postoperative analgesia after modified radical mastectomy: A randomised controlled double-blinded trial.

ABSTRACT

Background and Aims: Nearly half of the patients following breast cancer surgery experience postoperative pain. The interfascial plane for the pectoral nerve (PECS) block, along with dexmedetomidine, can alleviate this pain. Methods: After institutional ethics committee clearance and written informed consent, this randomised, double-blind study was conducted on 60, 18-60 years female patients, who were scheduled for modified radical mastectomy (MRM) under general anaesthesia. Patients were randomised into Group L (20 ml of 0.25% levobupivacaine) and Group DL (20 ml of 0.25% levobupivacaine with 0.5 µg/kg of dexmedetomidine). After resection of the tumour and securing haemostasis, under strict aseptic precaution, 10 ml of the study drug was injected under direct vision between the pectoralis major and pectoralis minor and 10 ml between pectoralis minor and serratus anterior muscles by the operating surgeon (direct PECS block). The primary outcome was to compare the duration of analgesia. Normally distributed variables were compared using Student's t-test, and non-normally distributed variables were compared using the Mann-Whitney U-test. Qualitative data were analysed using Chi-square/Fisher's exact test. Statistical significance was kept at P < 0.05. Results: The median time of the first analgesic requirement was 8 [inter-quartile range (IQR) 6-8] h in Group L and 18 (IQR 16-20) h in Group DL (W = 17.000, P < 0.001). The mean total opioid consumption of Group L was 12.53 [standard deviation (SD) 2.29] mg in the first 24 h and 6.93 (SD 1.89) mg in Group DL. Conclusion: Adding 0.5 µg/kg dexmedetomidine to 20 ml of levobupivacaine enhances the duration of analgesia of direct PECS block in patients undergoing MRM.