Low-dose ketamine lowers inflammation after pyometra surgery in dogs

Abstract

OBJECTIVE: To determine the effects of subanesthetic ketamine in dogs with pyometra on C-reactive protein (CRP) concentrations following surgery. DESIGN: Prospective, nonconcealed, alternating allocation controlled trial. SETTING: Veterinary teaching hospital. ANIMALS: Sixteen dogs diagnosed with pyometra. INTERVENTIONS: The tentative diagnosis of canine pyometra was based on compatible history, physical examination findings, ultrasonographic findings, and hematological evaluation. Two different anesthesia and analgesic protocols with and without low-dose ketamine were used during and following ovariohysterectomy in 16 female dogs (n = 8 per group) that were diagnosed with naturally occurring pyometra. Dogs were sequentially allocated to treatment groups in an alternating fashion without concealment. Serum was collected before, 24, and 48 hours after surgery for CRP measurement. MEASUREMENTS AND MAIN RESULTS: Perioperative physical parameters in the 2 groups of dogs were similar. The serum concentrations of CRP in both groups were essentially the same before surgery, but significantly increased in the control group and decreased in ketamine group at 48 hours after surgery. CONCLUSIONS: Low-dose ketamine attenuated the postoperative concentration of serum CRP in dogs with pyometra compared with dogs that did not receive ketamine in the perioperative period. Further studies are warranted to determine the clinical implications of these findings.