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Abstract

Background & objective: Most patients undergoing modified radical mastectomy (MRM) suffer significant acute postoperative pain. Anesthetists have tried various analgesic regimens to control the pain, including injectables and nerve blocks. This study compared the analgesic efficacy of preoperative oral gabapentin with and without intravenous infusion of dexmedetomidine (DEX) in patients undergoing MRM under general anesthesia.
Methodology: This randomized, double-blind clinical trial included 60 patients scheduled for MRM. They were randomly allocated to one of the two equal groups. Both groups received oral gabapentin 600 mg one hour before surgery. Group G (n = 30) received a 50 mL normal saline bolus and continuous intraoperative infusion (10 mL/hour). Group DG (n = 30) received a loading dose of DEX 1 µg/kg just before induction of anesthesia, followed by a continuous intraoperative infusion of DEX (0.5 µg/kg/hour). Outcome measures were duration of analgesia, intraoperative fentanyl consumption, postoperative morphine consumption, and VAS scores at rest and on movement.
Results: Duration of postoperative analgesia was significantly longer in the Group DG compared to the Group G (545 ± 49 min. vs. 288 ± 38 min., P < 0.001). Total fentanyl consumption was lower in the Group DG as compared to Group G (30.8 ± 2.0 vs. 41.6 ± 3.4 µg), P < 0.001. The two groups had no significant difference in postoperative morphine consumption (P = 0.405). VAS scores at rest and with movement were significantly lower in the Group DG during the postoperative period.
Conclusion: The analgesic effect of a combination of preoperative oral gabapentin plus perioperative dexmedetomidine infusion is superior to that of oral gabapentin alone in patients undergoing MRM for breast cancer and results in lower VAS scores at rest and with movement.
Abbreviations: α-2AR: α-2-adrenoceptor, DEX: dexmedetomidine, GA: General Anesthesia, MRM: Modified radical mastectomy, PACU: post-anesthesia care unit, VAS: Visual Analogue Scale
Keywords: Analgesia; Dexmedetomidine; Fentanyl; General Anesthesia; Modified radical mastectomy; Morphine
Citation: Ismail H, Ali AR, Samir M, Gamal RM, Fayez S. Oral gabapentin with and without intravenous dexmedetomidine for postoperative analgesia after modified radical mastectomy: a randomized, controlled, double-blind trial. Anaesth. pain intensive care 2025;29(6):447-54. DOI: 10.35975/apic.v29i6.2886
Received: September 24, 2024; Revised: January 05, 2025; Accepted: July 09, 2025