Development of a reference interval for urinary ammonia-to-creatinine ratio in feline patients.

BACKGROUND: Disruption of acid-base homeostasis can lead to many clinical problems. Ammonia excretion by the kidneys is critical to maintaining acid-base homeostasis through bicarbonate production. Measurement of ammonia excretion may help determine if the kidneys are properly functioning in maintaining acid-base balance. Reference intervals are essential tools for clinical decision-making but do not currently exist for urinary ammonia-to-creatinine ratio (UACR) in feline patients. OBJECTIVE: This study aimed to generate a reference interval (RI) for UACR in healthy adult cats. METHODS: The study used samples from client-owned adult healthy cats that presented to the University of Florida Primary Care and Dentistry service (n = 92). Physical examination, serum biochemistry, urinalysis, urine ammonia, and creatinine concentrations were measured. Cats were excluded if there were significant abnormalities in their urinalysis or biochemistry panel. The RI for UACR was calculated according to the recommendation of the American Society for Veterinary Clinical Pathology. The UACR was evaluated for correlation with serum bicarbonate, weight, age, and sex. RESULTS: The RI for UACR was 3.4-20.7 with 90% confidence intervals for the lower and upper limits of (3.0-3.7) and (16.0-23.7), respectively. No significant correlation with age, sex, or weight was found. There was no discernable relationship between serum bicarbonate and UACR. CONCLUSIONS: Establishing an RI for UACR in healthy adult cats will allow further studies to determine if changes in UACR are observed during specific disease states.

Evaluation of clinical examination location on stress in cats: a randomized crossover trial.

OBJECTIVES: The objective of this study was to quantify the effects of owner separation and physical examination location on fear, anxiety and stress (FAS) behavioral indicators in cats. METHODS: The study was a prospective, non-blinded, randomized, two-period, two-treatment crossover trial. Healthy adult cats presenting for wellness or dental evaluations at a single veterinary teaching hospital received three physical examinations: a baseline assessment (owner present) followed by physical examinations in both a treatment area (owner absent [TAOA]) and an examination room (owner present [EROP]). The physical examination sequence order was randomized. Low-stress handling techniques were used for all examinations. The primary endpoints were heart rate (HR; beats per min [bpm]) and total FAS scores. HR was measured by auscultation, and FAS by five specific behaviors scored as 0/1 and summed for each assessment period. RESULTS: Twenty-one healthy cats were enrolled. HR measured at entry (baseline) was a significant determinant of subsequent HR readings. HR measured during examinations conducted in both EROP and TAOA were elevated to levels indicative of stress (>180 bpm). HR was significantly higher for TAOA relative to EROP (30 bpm, 95% confidence interval 18-43; P <0.001). Behavioral FAS scores showed no statistically significant effects of sequence or room. FAS scores for TAOA assessments were clinically elevated relative to baseline (1.5 FAS, SE 0.7; P = 0.05); EROP FAS scores relative to baseline did not differ statistically (0.5 units, SE = 0.5; P = 0.43). CONCLUSIONS AND RELEVANCE: Owner separation coupled with physical examination location can result in clinically significant increases in perceived stress in cats, and compromise vital sign assessments. Whenever possible, physical examinations and procedures should take place with the owner present with separation from unfamiliar dogs and cats.