Prevalence of Gastroesophageal Reflux in Cats During Anesthesia and Effect of Omeprazole on Gastric pH.

BackgroundGastroesophageal reflux (GER) is poorly characterized in anesthetized cats, but can cause aspiration pneumonia, esophagitis, and esophageal stricture formation.ObjectiveTo determine whether pre-anesthetic orally administered omeprazole increases gastric and esophageal pH and increases serum gastrin concentrations in anesthetized cats, and to determine the prevalence of GER using combined multichannel impedance and pH monitoring.AnimalsTwenty-seven healthy cats undergoing elective dental procedures.MethodsProspective, double-masked, placebo-controlled, randomized clinical trial. Cats were randomized to receive 2 PO doses of omeprazole (1.45-2.20 mg/kg) or an empty gelatin capsule placebo 18-24 hours and 4 hours before anesthetic induction. Blood for measurement of serum gastrin concentration was collected during anesthetic induction. An esophageal pH/impedance catheter was utilized to continuously measure esophageal pH and detect GER throughout anesthesia.ResultsMean gastric pH in the cats that received omeprazole was 7.2 ± 0.4 (range, 6.6-7.8) and was significantly higher than the pH in cats that received the placebo 2.8 ± 1.0 (range, 1.3-4.1; P < .001). Omeprazole administration was not associated with a significant increase in serum gastrin concentration (P = .616). Nine of 27 cats (33.3%) had ≥1 episode of GER during anesthesia.Conclusions and clinical relevancePre-anesthetic administration of 2 PO doses of omeprazole at a dosage of 1.45-2.20 mg/kg in cats was associated with a significant increase in gastric and esophageal pH within 24 hours, but was not associated with a significant increase in serum gastrin concentration. Prevalence of reflux events in cats during anesthesia was similar to that of dogs during anesthesia

Treatment of acute pain in cats

The cat's popularity as a pet continues to grow, with the most recent surveys showing approximately 17% of the population live with cats. This increased popularity of cats invariably means that more cats are presented to veterinary surgeons for surgery and treatment of painful conditions, but it seems that the treatment of pain in the cat has lagged behind that of other species. Lack of analgesic administration may well stem from the difficulties in assessing pain in the cat, but is probably compounded by the false perceptions of the likelihood of severe side effects occurring more frequently with the use of opioids and non-steroidal anti-inflammatory drugs in cats, thereby inadvertently denying them the analgesics they require. This article complements a previous article covering the assessment of acute pain in the cat (White, 2016); the aim of this second article is to provide an evidence-based framework to follow for the treatment of acute pain in the cat

Pharmacokinetics of buprenorphine following intravenous and intramuscular administration in male rhesus macaques (Macaca mulatta)

This study reports the pharmacokinetics of buprenorphine in conscious rhesus macaques (Macaca mulatta) after intravenous (i.v.) and intramuscular (i.m.) administration. Four healthy, opioid-naïve, socially housed, adult male macaques were used. Buprenorphine (0.03 mg/kg) was administered intravenously as a bolus or intramuscularly on separate occasions. Blood samples were collected prior to, and up to 24 h, postadministration. Serum buprenorphine concentrations were analyzed with liquid chromatography-mass spectrometry. Noncompartmental pharmacokinetic analysis was performed with commercially available software. Mean residence time in the i.v. study as compared to the i.m. study was 177 (159-189) vs. 185 (174-214) min, respectively [median (range)]. In the i.v. study, concentration back-extrapolated to time zero was found to be 33.0 (16.8-57.0) ng/mL [median (range)]. On the other hand, the maximum serum concentration found in the i.m. study was 11.8 (6.30-14.8) ng/mL [median (range)]. Rhesus macaques maintained concentrations >0.10 ng/mL for over 24 h in the i.v. study and over 12 h in the i.m. study. Bioavailability was found to be 68.1 (59.3-71.2)% [median (range)]. No significant adverse effects were observed in the monkeys at the 0.03 mg/kg dose of buprenorphine during either study

Pharmacokinetics of tramadol following intravenous and oral administration in male rhesus macaques (Macaca mulatta)

Recently, tramadol and its active metabolite, O-desmethyltramadol (M1), have been studied as analgesic agents in various traditional veterinary species (e.g., dogs, cats, etc.). This study explores the pharmacokinetics of tramadol and M1 after intravenous (IV) and oral (PO) administration in rhesus macaques (Macaca mulatta), a nontraditional veterinary species. Rhesus macaques are Old World monkeys that are commonly used in biomedical research. Effects of tramadol administration to monkeys are unknown, and research veterinarians may avoid inclusion of this drug into pain management programs due to this limited knowledge. Four healthy, socially housed, adult male rhesus macaques (Macaca mulatta) were used in this study. Blood samples were collected prior to, and up to 10 h post-tramadol administration. Serum tramadol and M1 were analyzed using liquid chromatography-mass spectrometry. Noncompartmental pharmacokinetic analysis was performed. Tramadol clearance was 24.5 (23.4-32.7) mL/min/kg. Terminal half-life of tramadol was 111 (106-127) min IV and 133 (84.9-198) min PO. Bioavailability of tramadol was poor [3.47% (2.14-5.96%)]. Maximum serum concentration of M1 was 2.28 (1.88-2.73) ng/mL IV and 11.2 (9.37-14.9) ng/mL PO. Sedation and pruritus were observed after IV administration

Pharmacokinetics of dexmedetomidine, MK-467, and their combination following intravenous administration in male cats.

This study characterized the pharmacokinetics of dexmedetomidine, MK-467, and their combination following intravenous bolus administration to cats. Seven 6- to-year-old male neutered cats, weighting 5.1 ± 0.7 kg, were used in a randomized, crossover design. Dexmedetomidine [12.5 (D12.5) and 25 (D25) μg/kg], MK-467 [300 μg/kg (M300)] or dexmedetomidine (25 μg/kg) and MK-467 [75, 150, 300 or 600 μg/kg-only the plasma concentrations in the 600 μg/kg group (D25M600) were analyzed] were administered intravenously, and blood was collected until 8 hours thereafter. Plasma drug concentrations were analyzed using liquid chromatography/mass spectrometry. A two-compartment model best fitted the data. Median (range) volume of the central compartment (mL/kg), volume of distribution at steady state (mL/kg), clearance (mL min/kg) and terminal half-life (min) were 342 (131-660), 829 (496-1243), 14.6 (9.6-22.7) and 48 (40-69) for D12.5; 296 (179-982), 1111 (908-2175), 18.2 (12.4-22.9) and 52 (40-76) for D25; 653 (392-927), 1595 (1094-1887), 22.7 (18.5-36.4) and 48 (35-60) for dexmedetomidine in D25M600; 117 (112-163), 491 (379-604), 3.0 (2.0-4.5) and 122 (99-139) for M300; and 147 (112-173), 462 (403-714), 2.8 (2.1-4.8) and 118 (97-172) for MK-467 in D25M600. MK-467 moderately but statistically significantly affected the disposition of dexmedetomidine, whereas dexmedetomidine minimally affected the disposition of MK-467