Objective—To evaluate the effects of perioperative oral administration of tramadol, firocoxib, and a tramadol-firocoxib combination on signs of pain and limb function after tibial plateau leveling osteotomy in dogs.
Animals—30 adult client-owned dogs with unilateral cranial cruciate ligament disease.
Procedures—Dogs were allocated into 3 treatment groups (tramadol, firocoxib, and a tramadol-firocoxib combination). Signs of pain (short-form Glasgow composite measure pain scale), serum cortisol concentrations, and limb function (pressure platform gait analysis) were recorded at several time points before surgery and through 3 days after surgery. Outcome measures were compared among groups.
Results—A significantly greater number of dogs in the tramadol group (8/10 dogs) had a pain score > 6 after surgery, compared with the other groups. No significant differences were detected in the pain scores between the firocoxib and the tramadol-firocoxib combination groups. There were no significant differences in serum cortisol concentrations among the 3 groups. Limb function was significantly decreased for dogs in the tramadol group on days 1 and 2 after surgery and in the firocoxib group on day 1 after surgery. Although limb function decreased for dogs in the tramadol-firocoxib combination group, the change was not significant for any day after surgery.
Conclusions and Clinical Relevance—Dogs that received firocoxib orally, alone or in combination with tramadol, had lower pain scores, lower rescue opiate administration, and greater limb function than dogs that received only tramadol. When used alone, oral administration of tramadol may not provide sufficient analgesic efficacy to treat dogs with pain after orthopedic surgical procedures.
Objective—To determine the relationship between serum cortisol concentration and pain severity as measured by force platform gait analysis in dogs with experimentally induced synovitis of the stifle joint.
Animals—10 healthy hound-type dogs.
Procedures—Dogs underwent 2 study phases. In the first phase, serum cortisol concentration, systolic arterial blood pressure, heart rate, and gait data were obtained at 0 (first sample), 2.5, 5, 7.5, and 10 hours. In the second phase, the same data were gathered immediately before (0 hours) and 2.5, 5, 7.5, and 10 hours after induction of acute urate synovitis in the left stifle joint. Data were statistically evaluated to compare changes in variable values over time and to determine the accuracy of serum cortisol measurements for diagnosis of acute orthopedic pain.
Results—Following induction of synovitis, ground reaction forces were significantly decreased relative to preinduction values at 2.5, 5.0, 7.5, and 10.0 hours and serum cortisol concentration was significantly increased at 2.5 hours. A cortisol concentration of ≥ 1.6 μg/dL indicated pain with a 91% sensitivity and 35% specificity.
Conclusions and Clinical Relevance—In this model, cortisol concentration may be useful for diagnosing pain in dogs. Although, with a cutoff of ≥ 1.6 μg/dL, pain would be detected in most dogs with pain, some pain-free dogs would also be identified as having pain. Conversely, dogs with a serum cortisol of < 1.6 μg/dL would be unlikely to have pain. Validation of this diagnostic test in a large, heterogeneous group of clinical patients is necessary.