Blinded, randomized, placebo-controlled study of the efficacy of bupivacaine liposomal suspension using static body weight distribution and subjective pain scoring in dogs after tibial plateau leveling osteotomy (TPLO) 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: 15 client-owned dogs receiving liposomal bupivacaine and 17 dogs receiving an equivalent volume of saline placebo, all with confirmed unilateral cranial cruciate ligament insufficiency. Methods: Preoperatively and up to 48 hours after surgery, Glasgow Composite Measure Short Form (CMPS-SF) pain scores were assigned and using a weight distribution platform, static body weight distribution (%BW[subsctipt dist]) to the operated limb was measured. Postoperatively, dogs also received carprofen 2.2 mg/kg subcutaneously every 12 hours. Rescue analgesia was provided. Treatment success was defined as not requiring rescue analgesia over the 48 hour postoperative period. Results: There was no difference between treatment success, postoperative opioid consumption, CMPS-SF pain scores, or %BW[subscript dist] in 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[subscript dist]. 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 %BW[subscript dist] measurement using a weight distribution platform, compared with saline placebo. Clinical Significance (or Impact): LB may not provide detectable analgesia for dogs recovering from TPLO and receiving postoperative carprofen.