Evaluation of gastrointestinal transit times and pH in healthy cats using a continuous pH monitoring system.

OBJECTIVES: The aim of this study was to characterize gastrointestinal (GI) transit times and pH in healthy cats. METHODS: GI transit times and pH were measured in six healthy, colony-housed, purpose-bred spayed female cats using a continuous, non-invasive pH monitoring system in a sequential order design. For the first period ('pre-feeding'), food was withheld for 20 h, followed by oral administration of a pH capsule. Five hours post-capsule administration, cats were meal-fed by offering them their daily allowance of food for 1 h. For the second period ('post-feeding'), food was withheld for 24 h and cats were fed for 1 h, after which a pH capsule was orally administered. Studies in both periods were repeated three times. GI transit times and pH were compared between the two periods. RESULTS: The median transit times for the pre- and post-feeding periods, respectively, were: gastric - 94 mins (range 1-4101) and 1068 mins (range 484-5521); intestinal - 1350 mins (range 929-2961) and 1534 mins (range 442-2538); and GI - 1732 mins (range 1105-5451) and 2795 mins (range 926-6563). The median GI pH values for the first and second periods, respectively, were: esophageal - 7.0 (range 3.5-7.8) and 4.5 (range 2.9-6.4); gastric - 2.7 (range 1.7-6.2) and 2.0 (range 1.1-3.3); intestinal - 8.2 (range 7.6-8.7) and 7.8 (range 6.7-8.5); first-hour small intestinal - 8.2 (range 7.4-8.7) and 8.3 (range 7.9-8.6); and last-hour large intestinal - 8.5 (range 7.0-8.9) and 7.8 (range 6.3-8.7). Gastric (P <0.0020) and intestinal pH (P <0.0059) were significantly increased in the pre-feeding period compared with the post-feeding period. CONCLUSIONS AND RELEVANCE: Gastric and intestinal pH differed significantly when the capsule was administered 5 h prior to feeding compared with 1 h after feeding. Transit times for both periods showed high degrees of intra- and inter-individual variability.

Appetite-stimulating effects of once-daily omeprazole in cats with chronic kidney disease: Double-blind, placebo-controlled, randomized, crossover trial.

BACKGROUND: Cats with moderate to advanced chronic kidney disease (CKD) often display clinical signs such as vomiting and decreased appetite, and frequently receive omeprazole or other acid suppressants despite a lack of evidence to support their use. HYPOTHESIS/OBJECTIVES: To evaluate the effect of once-daily PO omeprazole on appetite in cats with CKD. We hypothesized that omeprazole would improve subjective appetite assessments in cats with CKD. ANIMALS: Fourteen client-owned cats with International Renal Interest Society (IRIS) stage 2 or 3 CKD and hyporexia. METHODS: Cats were prospectively enrolled in a multi-institutional, double-blinded, randomized, crossover study to evaluate the effect of a 14-day trial of once-daily PO omeprazole (1 mg/kg) or placebo (lactose gel capsule) on vomiting frequency and appetite. A daily log was completed by the owner during all treatment and rest periods to assess appetite using a subjective, qualitative, and 5-point scoring system. Mixed model analyses of variance were performed to determine if average daily percentage food consumed or appetite score, as measured by subjective owner assessment, differed between treatments. RESULTS: Compared to placebo, a negligible but statistically significant difference in percentage of food consumed was observed between treatments (P = .04) with once-daily omeprazole treatment resulting in a 2.7% increase in food consumption compared to placebo. No significant difference, however, was found in appetite score, body weight, or serum creatinine concentration between treatments. CONCLUSIONS AND CLINICAL IMPORTANCE: Once-daily omeprazole does not markedly increase appetite in cats with CKD and should not be used as a first-line treatment in the absence of evidence of gastrointestinal ulceration.