SOFT-TISSUE AND INTRA-ARTICULAR INJECTION WITH EPINEPHRINE AND NARCOTIC: A BENEFICIAL EFFECT IN TKA

Abstract

Introduction and Aims: Adequacy of post-operative pain control can effect total knee arthroplasty (TKA) outcomes. We examine the effectiveness of a simple and inexpensive method using long-acting local anesthetic (bupivacaine) with epinephrine and morphine injection on controlling pain, blood loss, and motion in primary TKA.

Method: We retrospectively reviewed 170 patients who underwent 208 primary TKA, by a single surgeon between October 2001 and December 2002. The control group of 75 patients (99 knees) had received no intra-operative injections. The study group of 95 patients (109 knees) had received intra-operative injection of 0.25 percent bupivacane with epinephrine and morphine divided two-thirds soft-tissue injection and one-third intra-articular injection. Bilateral simultaneous TKA in the study group received a divided anaesthetic dose.

Results: The control group required significantly more breakthrough narcotic (85 percent vs 67 percent; p=0.004); and required more narcotic reversal for over-sedation. The study group had significantly higher ROM at discharge 63 degrees vs 52 degrees. Lower ROM at discharge was associated with manipulation (p equals 0.001). The study group required less transfused blood (mean 0.03 vs 0.1 units), and had significantly lower bleeding indices 2.7 vs 3.5.

Conclusion: Preemptive analgesia with intra-articular and soft-tissue injection of long-acting local anesthetic with epinephrine and morphine appears to decrease need for rescue narcotics and reversal agents. The use of the injection also increases ROM at discharge, which reduces the need for manipulation. Lastly, the bleeding index and transfusion requirements are significantly reduced. This inexpensive method is effective in improving the post-operative course of primary TKA.