Short-term effect of sedation on kidney function markers in cats with chronic kidney disease

Objective: To determine the short-term effect of sedation on GFR markers in cats with chronic kidney disease (CKD). Methods: This was a prospective observational study involving client-owned cats with CKD undergoing abdominal sonography. Each cat received 50 mg oral gabapentin, 0.3 mg/kg butorphanol, and 0.3 mg/kg midazolam IM followed by 1 mg/kg alfaxalone IV to effect. Presedation blood tests included hematology and biochemistry. A second blood test for GFR markers (symmetric dimethylarginine SDMA and creatinine) was collected at the point of maximum sedation (20 cats) or 2 hours after sedation (12 cats). Results: 20 cats had presedation SDMA and creatinine concentrations of 19 µg/dL median (IQR, 15 to 24.5) and 200 µmol/L median (IQR, 147.5 to 260), respectively. These were not significantly different from samples from the point of maximal sedation (SDMA: median, 19 µg/dL; quantile Q-1 to Q3, 15 to 24.5; P = .31; creatinine: median, 200 µmol/L; IQR, 147.5 to 255; P = .71). Twelve cats had presedation SDMA and creatinine concentrations of 22 µg/dL median (IQR, 19.5 to 24.5) and 210 µmol/L median (IQR, 165 to 260), respectively. These were not significantly different from samples obtained 2 hours after sedation (SDMA: median, 25 µg/dL; IQR, 20 to 26; P = .51; creatinine: median, 200 µmol/L; Q1 to Q3, 175 to 280; P = .06). The only adverse effect was prolonged sedation in some cats. Conclusions: Sedation with gabapentin, butorphanol, midazolam, and alfaxalone was an effective protocol for cats with CKD undergoing noninvasive diagnostic procedures and was not associated with short-term changes in GFR markers. Clinical Relevance: The sedation protocol described is safe and effective in cats with CKD undergoing routine procedures.