Ketamine Versus Dexmedetomidine as Adjuvants to Bupivacaine in Modified Pectoralis Plane Block for Analgesia in Patients Undergoing Modified Radical Mastectomy

Background: Effective perioperative pain management is crucial for improving postoperative recovery and reducing the use of opioids in patients undergoing modified radical mastectomy (MRM). The current study compares the analgesic impact of ketamine versus dexmedetomidine as adjuvants to bupivacaine in modified pectoralis (PECS) plane block in this category of patients. Methods: In this prospective randomized double-blinded clinical trial which included sixty-eight women with breast cancer scheduled for modified radical mastectomy who were randomized into two equal groups. Group K received ultrasound-guided modified PECS block with ketamine added to bupivacaine. Group D received an ultrasound-guided modified PECS block with dexmedetomidine added to bupivacaine. Results: Compared with Group D, VAS scores were significantly higher in Group K at 6 hours and 12 hours (p <0.05). The number of patients who needed rescue analgesia (nalbuphine) was significantly higher in Group K (61.7%) than in Group D (35.3%). The time for the first rescue analgesia was significantly shorter in Group K than in Group D (18 hrs±3.30vs 12.96±2.7) (p<0.05). Moreover, the total nalbuphine consumption during the 24 postoperative hours was significantly higher in Group K than in Group D (p<0.05). Conclusion: The findings suggest that dexmedetomidine provided superior analgesic effects compared to ketamine, as demonstrated by longer time to initial rescue analgesia, decreased requirement for rescue analgesia, and lower postoperative Visual Analog Scale (VAS) ratings at 6 and 12 hours. Additionally, the dexmedetomidine group consumed considerably less fentanyl intraoperatively. indicating better intraoperative analgesic efficacy.