Analgesic Effect of Intra-articular Morphine or Dexmedetomidine Added with Levobupivacaine in Arthroscopic Knee Surgeries - A Comparative Evaluation

Abstract

Introduction: Knee arthroscopy is associated with variable amount of postoperative pain. In an attempt to improve postoperative analgesia, intra-articular injection of local anaesthetic in combination with other agent have been studied. However, the best combination is not known. Aim: To compare the analgesic efficacy of intra-articular injection of morphine and dexmedetomidine when added with levobupivacaine in arthroscopic knee surgeries. Materials and Methods: Seventy eight patients, scheduled to undergo elective arthroscopic procedure under spinal anaesthesia were recruited for the study. All the patients received 18 ml of 0.25% levobupivacaine however in addition to this Group M patients received 8 mg (2 ml) morphine, Group D patients received 100µg (2 ml) of dexmedetomidine while Group C patients received 2 ml of isotonic saline intraarticularly. Postoperatively the intensity of pain was assessed using Numerical Rating Scale (NRS). Rescue analgesia was given at NRS ≥ 4. The duration of analgesia and total diclofenac consumption was noted. Results: The mean duration of analgesia was longest in Group M (576.20±67.09 minutes) followed by Group D (460.93±38.95 minutes) and Group C (370.27±58.80 minutes) statistically this difference was found to be highly significant (p-value < 0.001). Total consumption of diclofenac in 24 hours was found lowest in group M (86.25±27.48 mg) followed by group D (110.87±44.48 mg) and group C (141.35±44.13 mg) this difference was found to be highly significant (p-value < 0.001). Conclusion: Morphine when added with levobupivacaine in patients undergoing arthroscopic knee surgery improves the quality and prolongs the duration of postoperative analgesia.

Keywords

• anaesthetic technique
• diclofenac sodium
• postoperative analgesia
• synergistic effect