Comparative Study of Effect of Periarticular Fentanyl and Dexmedetomidine Injection for Pain Management in Total Knee Arthroplasty a Randomized Control Trial

Abstract

Abstract Introduction: Post-operative pain following total knee arthroplasty (TKA) remains a major challenge and may delay rehabilitation, ambulation, and functional recovery. Periarticular infiltration analgesia has emerged as an effective component of multimodal pain management protocols. Dexmedetomidine and fentanyl are commonly used analgesic adjuvants; however, comparative evidence regarding their periarticular use in TKA remains limited. Objectives: The aim of the study was to compare the analgesic efficacy of periarticular fentanyl and dexmedetomidine injection in patients undergoing TKA by evaluating post-operative pain relief, duration of analgesia, cumulative analgesic requirement, time to ambulation, and duration of hospital stay following surgery. Materials and Methods: This prospective hospital-based randomized controlled trial was conducted in the Department of Orthopaedics at Teerthanker Mahaveer Medical College and Research Centre over 18 months. A total of 90 patients undergoing TKA were randomly allocated into three groups comprising 30 patients each: Group A (Bupivacaine + Fentanyl), Group B (Bupivacaine + Dexmedetomidine), and Group C (Bupivacaine + Saline). Post-operative pain was assessed using the Visual Analog Scale. Cumulative analgesic requirement, ambulation time, hospital stay, and post-operative morbidity scores were also evaluated. Appropriate statistical tests and multiple linear regression analysis were applied. Results: Patients receiving periarticular dexmedetomidine demonstrated significantly lower post-operative pain scores at 6 h (5.63 ± 1.06) compared with fentanyl (6.50 ± 1.10) and saline groups (7.23 ± 1.22) (P = 0.021). The dexmedetomidine group also showed the lowest cumulative post-operative diclofenac requirement (597.50 ± 153.17 mg) compared with the fentanyl (680.00 ± 132.02 mg) and saline groups (758.33 ± 109.13 mg) (P = 0.001). Regression analysis identified dexmedetomidine as an independent predictor of reduced post-operative analgesic requirement (β = −102.4, P = 0.001). Conclusion: Periarticular dexmedetomidine infiltration provided superior post-operative analgesia, reduced cumulative analgesic consumption, and improved post-operative recovery following TKA compared with fentanyl and saline infiltration.