The Complete Abstract: Liposomal Bupivacaine Infiltration of the Distal Femoral Triangle for TKA

Abstract: 618

Medically Challenging Cases

LIPOSOMAL BUPIVACAINE FOR DISTAL FEMORAL TRIANGLE AND ANTERIOR AND POSTERIOR FEMORAL CUTANEOUS NERVES FOR TOTAL KNEE ARTHROPLASTY

Mike Guzman

Community East Hospital

Introduction

Various pain pathways and multimodal regimens have been proposed for Total Knee Arthroplasty (TKA). Liposomal bupivacaine is FDA approved for infiltration into tissues for postoperative analgesia. A recent SEE program 2019 question review stated no difference between surgeon liposomal bupivacaine injection and traditional nerve block techniques. Optimal TKA outcomes can occur with sensory only techniques with excellent pain scores. Enclosed is a description of four patients receiving ultrasound guided liposomal bupivacaine into the distal femoral triangle and cutaneous branches of the femoral nerve.

Materials and Methods

These reports are devoid of patient identifiable information and are exempt from IRB review requirements as per Community Health Network policy.

Four patients received TKA at our institution with the procedures performed by three different surgeons. Postoperative pain pathway included hypobaric spinals and infiltration of the distal femoral triangle and cutaneous branches of the femoral nerve with liposomal bupivacaine. The patients were placed in an operative side up lateral decubitus position after placement of bupivacaine 0.5% 2 ml. A mixture of liposomal bupivacaine 266 mg (20 ml) was mixed with bupivacaine 75 mg (30 ml) and diluted with normal saline 50 ml for a total mixture volume of 100 ml. A four inch ultrasound block needle was used for mixture infiltration. Sterile technique was used. The posterior, anterior medial, and anterior lateral femoral cutaneous nerves were ultrasound identified between the fascia iliaca and fascia lata, with 20 ml of the mixture infiltrated at each site. The distal femoral cutaneous triangle was ultrasound identified and 30 ml of the mixture was infiltrated. The remaining ten ml of mixture was infiltrated using a 25 gauge needle in an area of the infrapatellar branch of the saphenous nerve five centimeters medial to the tibia tubercle. Patients received intravenous ketolorac 15 mg every 6 hours, intravenous acetaminophen 1000 mg times two doses, and oxycodone 5 to 10 mg as needed. All of the patients received a general anesthetic with propofol induction and sevoflurane maintenance.

Results/Case Report

The hypobaric spinal provided adequate pain relief for all four patients in PACU. The spinal effect usually resolved within four hours on the orthopedic floor. Patients were able to ambulate to a chair within six hours. The pain scores were 0-2/10 at rest and less than 3/10 after physical therapy. Two of the patients were discharged postoperative day one and the other two on day two.

Discussion

Liposomal bupivacaine infiltration is FDA approved for postoperative analgesia. Ultrasound guided infiltration of sensory only techniques for TKA allows earlier, remarkable flexion and extension motor function. The patient’s speech, appetite, facial expression, and overall behavior were beyond our expectations.