The Effect of Bilateral Femoral Nerve Block Combined with Intravenous Patient-controlled Analgesia after a Bilateral Total Knee Replacement

Abstract

Background: Postoperative pain is a major concern after total knee replacement (TKR). Intravenous patient-controlled analgesia (IV PCA) is very easily controlled method for managing pain, however it is less effective than other methods, especially immediately after TKR. Therefore, we evaluated the effect of the femoral nerve block combined with IV PCA after a unilateral TKR for postoperative pain control. Methods: The patients in group I (n = 20) were given only IV PCA with morphine and group II (n = 20) taken femoral nerve block before extubation followed by IV PCA. We evaluated the effects of the femoral nerve block with 12 ml of 0.25% bupivacaine and epinephrine 1:400,000 on the postoperative cumulative opioid consumption, hourly dose during each time interval, numerical rating pain score, side effects and hemodynamics. Results: Cummulative opioid consumption was decreased in group II. The pain score in group II was lower than that in group I immediately after recovery of awareness and 3, 6 hours postoperatively. The hourly dose in group II was also lower than that in group I until 6 hours postoperatively. But there was no difference in side effects between the groups. Conclusions: We concluded that femoral nerve block is effective as an easy adjuvant of IV PCA for pain management during early postoperative period after TKR. (Korean J Anesthesiol 2008; 55: 596~601)