Preventive Epidural Analgesia in Bilateral Single-Stage Knee Arthroplasty: A Randomized Controlled Trial

INTRODUCTION: Although controversial, pre-emptive analgesia has shown some promise in preventing altered pain perception and reducing pain amplification after surgery. Hence, it has the potential to be more effective than a similar analgesic regimen started after surgery with an appropriate combination of patient category and analgesic modality. Hence, the present study was undertaken to evaluate the effect of preventive epidural analgesia in reducing pain severity and duration after bilateral single-stage knee arthroplasty. METHODS: Fifty patients, 18–70 years, with American Society of Anesthesiologists physical status class I & II posted for bilateral single-stage knee replacement under regional anesthesia were randomly allocated into preventive versus postoperative epidural analgesia group to compare severity of post-operative pain, analgesic consumption, day of mobilization, C-reactive protein (CRP) levels, and hospital stay. RESULTS: The pain score after surgery [2.0 (1.5, 2.0); 3.0 (1.5, 3.0), p = 0.005] and day of mobilization [(2. 92 ± 0. 28; 3. 31 ± 0. 48; p value 0.02)] were significantly lesser in the preventive epidural group. However, there was no difference in the hospital stay (9.92 ± 3.71 and 9.00 ± 2.12, p = 0.95) and analgesic consumption (65.38 ± 37.55 and 73.08 ± 43.85, p = 0.30). The preventive group had a larger drop in CRP and experienced a lesser number of days with pain after surgery as compared to the controls [(64.29 ± 21.29); (142.37 ± 80.04), p = 0.0001]. Six patients in the preemptive group (24%) and 13 of the control group (24 vs. 56.5%; p = 0.02) had chronic postsurgical pain. CONCLUSIONS: Preventive epidural analgesia reduces the severity and number of chronic pain days after bilateral single-stage knee replacement. TRIAL REGISTRATION: The study was registered in the Indian national registry (CTRI/2017/03/008240 on 28/03/2017).