Comparison of the Efficacy of Continuous Femoral Nerve Block With Epidural Analgesia for Postoperative Pain Relief After Unilateral Total Knee Replacement.

Introduction With recent developments in postoperative pain management after total knee replacement (TKR), the continuous femoral nerve block is becoming a common practice. The purpose of this study was to compare a femoral nerve block with time-tested epidural analgesia in a tertiary care setup in a developing country. Methodology A randomized control trial took place at Shifa International Hospital (SIH), Islamabad, Pakistan. Sixty patients, aged 40 to 90 years old, 12 males and 48 females, who were undergoing unilateral TKR for osteoarthritis in American Society of Anesthesiologists (ASA) physical status classes I and II, weighing between 50 and 99 kg, and fully able to understand and respond to the numeric rating scale (NRS) were included in the study. While patients belonging to ASA physical status class ≥3, with chronic opiate therapy, having allergies to local anesthetics or equipment material, or with neuromuscular disease, were excluded from the study. Ethical approval was obtained, and patients were divided into two groups, with group A given epidural and group B given a femoral nerve block for pain management postop. Data were collected. The pain was recorded using the NRS at six, 12, and 24 hours postop. Results The results for six hours and 12 hours were found to be significant. Patients in group A had a lower NRS rating postop as compared to group B and required a lesser amount of additional boluses for pain management.  Conclusion The femoral nerve block is inferior to epidural analgesia for pain management after unilateral TKR in the first 24 hours, with a greater need for extra boluses to relieve pain.