Blinded, randomized, placebo-controlled study of the efficacy of bupivacaine liposomal suspension using static bodyweight distribution and subjective pain scoring in dogs after tibial plateau leveling osteotomy surgery.

Abstract

OBJECTIVE: To compare the analgesic effect of surgical wound infiltration with liposomal bupivacaine (LB) to saline placebo in dogs after tibial plateau leveling osteotomy (TPLO). STUDY DESIGN: Blinded, randomized, placebo-controlled clinical prospective study. ANIMALS: Fifteen client-owned dogs receiving LB and 17 dogs receiving an equivalent volume of saline placebo, all with confirmed unilateral cranial cruciate ligament insufficiency. METHODS: Preoperatively and up to 48 h after surgery, Glasgow Composite Measure Short Form (CMPS-SF) pain scores were assigned and using a weight distribution platform, static bodyweight distribution (%BW) to the operated limb was measured. Postoperatively, dogs also received carprofen 2.2 mg/kg subcutaneously every 12 h. Rescue analgesia was provided. Treatment success was defined as not requiring rescue analgesia over the 48-h postoperative period. RESULTS: There was no difference between treatment success, postoperative opioid consumption, CMPS-SF pain scores, or %BWin dogs that received surgical wound infiltration with LB compared with those receiving saline placebo, following TPLO. There was no linear correlation between CMPS-SF pain scores and %BW. CONCLUSION: For the population of dogs that underwent TPLO and received postoperative carprofen at our institution, LB did not provide an analgesic effect discernable by success/failure analysis, CMPS-SF pain scores, or %BWmeasurement using a weight distribution platform, compared with saline placebo. CLINICAL SIGNIFICANCE: LB may not provide detectable analgesia during the first 48 h for dogs recovering from TPLO and receiving only postoperative carprofen.