Comparative evaluation of Gabapentin and Clonidine for Premedication on postoperative analgesia in patient undergoing modified radical mastectomy under general anesthesia

Abstract

Background: Early post-operative pain is the most common complain after elective surgery. Gabapentine and Clonidine have antinociceptive property. This prospective, randomized study evaluated the effect of oral clonidine and oral gabapentin premedication on postoperative pain intensity, analgesic consumption and side effects in patient undergoing modified radical mastectomy. Methods: Ninety patients of ASA grade I or II, aged between 35 to 55 years undergoing MRM were randomly allocated to receive either Tablet gabapentin 600 mg (group G, n=30) or Tablet clonidine 200mcg (group C, n=30) or Tab placebo (group P, n=30) orally one hour before operation. They were anesthetized using the same technique. Postoperative visual analog scale (VAS) for pain, time of first analgesic and total amount of analgesic requirement was observed in the recovery room at 0, 2,6 and 12 hours following the surgery. Results: The patients’ characteristics were alike in three groups. The VAS pain scores at measured times were significantly lower in the gabapentin (3.0± 0.4, 3.4±0.5, 3.6± 0.5, 2.9±0.6) group as compared to clonidine ( 3.8± 0.7 , 4.4± 0.58, 4.8± 1.6, 3.7± 1.7) and placebo group (5.28±0.34, 6.6±0.32 ,5.2±0.8, 4.9±0.5). Time to first rescue analgesia was significantly longer in group G (10 .32± 0.62 hr) as compared to group C (7.24± 0.82 hr) and group P (1.34 ± 0.72 hr). The post-operative diclofenac sodium consumption in gabapentin group (22.12 ± 4.33) was significantly less than clonidine (75.2±7.41 mg, P<0.05) and placebo groups (150 ± 0.42mg) P<0.001. Nine patients in group G, fifteen patients in group C and all patients in group P required rescue analgesia postoperatively. Number of patients required > one dose of rescue analgesic were highest in placebo (30) group as compared to group G (1) and group C (8). Conclusion: Oral premedication with gabapentin significantly decreases the postoperative pain and diclofenac sodium consumption without any significant side effects.