Blood product usage and factors associated with transfusions in cats with hemoperitoneum: 33 cases (2018-2022)

Objective

To evaluate blood product usage in cats with hemoperitoneum. To secondarily evaluate factors associated with transfusion administration and the outcome of cats with hemoperitoneum.

Design

Retrospective study between the years 2018-2022.

Setting

University veterinary teaching hospital and private practice hospital.

Animals

33 cats admitted to the hospital diagnosed with hemoperitoneum from January 2018 to September 2022.

Measurements and main results

Medical records were retrospectively reviewed; signalment, point-of-care diagnostics, effusion characteristics, and transfusion administration information was recorded. The most common etiology associated with hemoperitoneum was neoplasia (51.5%). Fifty-one percent (51.5%) of cats received a blood transfusion during hospitalization with the majority of cats receiving multiple transfusion types (69%). The etiology of hemoperitoneum was not associated with receiving a transfusion (p = 0.28) Point-of-care diagnostics including packed cell volume (PCV), total solids (TS) and platelet count were not significantly associated with receiving a transfusion (p = 0.317, p = 0.11 and p = 0.82, respectively). The PCV and TS of the effusion was also not significantly associated with transfusions (p = 0.91 and p = 0.63, respectively). Sixteen cats (48%) survived to discharge. Transfusions were significantly associated with outcome and cats that received a transfusion were more likely to survive to discharge (p = 0.008).

Conclusion

In conclusion, hemoperitoneum from a variety of etiologies in cats is associated with a high proportion of transfusions. None of the evaluated point-of-care diagnostics were associated with transfusion administration in this study. Cats that received a transfusion were more likely to survive to discharge.

Echocardiographic caudal vena cava measurements in healthy cats and in cats with congestive heart failure and non-cardiac causes of cavitary effusions

BACKGROUND

Echocardiographic indices of the inferior vena cava have been associated with elevated right atrial pressures in humans.

HYPOTHESIS/OBJECTIVES

Describe caudal vena caval (CVC) sonographic dimensions in healthy cats compared to cats with cardiogenic cavitary effusion (CCE), cardiogenic pulmonary edema (CPE), or non-cardiac causes of cavitary effusion (NCE).

ANIMALS

30 healthy control cats and 52 client-owned cats with CCE, CPE, or NCE examined at two university hospitals.

METHODS

Sagittal 2-dimensional (2D) and M-mode CVC dimensions were acquired from the subxiphoid view. Caudal vena cava collapsibility index (CVC-CI) was calculated. Variables were compared between study groups using Kruskal-Wallis and Dunn's Bonferroni testing. Receiver operating characteristic curves were used to assess sensitivity and specificity for diagnostic categories.

RESULTS

Healthy cats had sagittal 2D and M-mode (median, interquartile range) CVC maximal dimensions of 2.4 mm (1.3-4.0) and 3.4 mm (1.5-4.9) and CVC-CI of 52% (45.2-61.8) and 55% (47.8-61.3), respectively. The CVC maximal dimensions in healthy controls were smaller than in cats with cavitary effusions or pulmonary edema (all P<0.05). CVC-CI was different between CCE and NCE (P<0.0001) with cutoffs of CVC-CI ≤38% (2D) or ≤29% (M-mode) being 90.5% and 85.7% sensitive, and 94.4% and 100% specific for diagnosis of CCE, respectively.

CONCLUSIONS AND CLINICAL IMPORTANCE

Caudal vena cava measurements are larger in cats with cavitary effusions and cats with CPE than healthy cats. In cats with cavitary effusion, decreased CVC-CI, ≤38% (2D) or ≤29% (M-mode), was helpful in distinguishing between cardiogenic and noncardiogenic etiology.

Ionophore coccidiostats - disposition kinetics in laying hens and residues transfer to eggs

Poultry production is linked with the use of veterinary medicinal products to manage diseases. Ionophore coccidiostats have been permitted for use as feed additives within the European Union (EU) for the prevention of coccidiosis in various species of poultry with except of laying hens. The presence of chemical residues in eggs is a matter of major concern for consumers' health. Despite such prohibition of use in laying hens, they were identified as the most common non-target poultry species being frequently exposed to these class of coccidiostats. Many factors can influence the presence of residues in eggs. Carryover of these class of coccidiostat feed additives in the feed of laying hens has been identified as the main reason of their occurrence in commercial poultry eggs. The physicochemical properties of individual compounds, the physiology of the laying hen, and the biology of egg formation are believed to govern the residue transfer rate and its distribution between the egg white and yolk compartments. This paper reviews the causes of occurrence of residues of ionophore coccidiostats in eggs within the EU with special emphasis on their disposition kinetics in laying hens, and residue transfer into eggs. Additional effort was made to highlight future modeling perspectives on the potential application of pharmacokinetic modeling in predicting drug residue transfer and its concentration in eggs.

Retrospective Evaluation of Clinical Bleeding in Dogs With Anticoagulant Rodenticide Toxicity—A Multi-Center Evaluation of 62 Cases (2010–2020)

Objective

To evaluate the most common locations of hemorrhage in dogs diagnosed with anticoagulant rodenticide intoxication.

Animals

Dogs presenting with hemorrhage secondary to anticoagulant rodenticide intoxication between at two university veterinary teaching hospitals.

Procedures

Medical records were searched from the years 2010 through 2020 and all records from dogs treated for hemorrhage secondary to anticoagulant rodenticide intoxication were reviewed. Dogs were diagnosed with anticoagulant rodenticide intoxication based on the combination of known exposure and prolonged coagulation testing, including prothrombin and activated thromboplastin time, or based on gas chromatography-mass spectrometry (GCMS). The diagnosis of hemorrhage was made based on physical exam findings, point-of-care ultrasound findings or radiography.

Results

Sixty-two dogs met the inclusion criteria and were included in the study. The most common sites of hemorrhage included: pleural space (hemothorax 37%), pulmonary parenchyma (24%), abdomen (24%), skin/subcutaneous (21%), gastrointestinal tract (18%), pericardium (13%), oral cavity (13%), nasal cavity (11%), ocular (8%), and urinary tract (7%). Overall, forty-five dogs (73%) had evidence of cutaneous or mucosal hemorrhage while thirty-three (53%) of dogs had evidence of cavitary hemorrhage. Forty-five percent of dogs had hemorrhage noted at only one site, while 55% experienced hemorrhage at more than one site. The location of hemorrhage and total number of hemorrhagic sites was not associated with survival or transfusion requirement.

Conclusions and Clinical Relevance

In conclusion, this study highlights that dogs with anticoagulant rodenticide intoxication present with diverse locations of hemorrhage and the majority of dogs had non-cavitary hemorrhage noted.

Pharmacokinetic Exposures Associated With Oral Administration of Sorafenib in Dogs With Spontaneous Tumors

Sorafenib is a multi-kinase small molecule inhibitor that targets serine/threonine and tyrosine kinases including the RAF kinase family, VEGFR-2, and PDGFR. The aim of this study was to evaluate the systemic pharmacokinetics of a previously defined tolerable oral dose of sorafenib in tumor-bearing dogs. Six client-owned dogs with a cytologic or histologic diagnosis of cancer were enrolled in this open-label, tolerability study. Dogs were administered sorafenib at an intended dose of 3 mg/kg and serum samples were obtained for analysis of sorafenib serum concentrations at 0, 1, 2, 6, 12, 24, 48, 72, 96, and 168 h post-drug administration. Median time to peak serum sorafenib concentration occurred at 4 h (range 2–12 h) resulting in an average serum concentration of 54.9 ± 33.5 ng/mL (118.2 ± 72.1 nM). Mean sorafenib levels declined by over 70% relative to peak serum concentrations by 24 h in all dogs, suggesting the value of at least twice daily administration. Doses of 3 mg/kg were well-tolerated and no patients in the study experienced adverse events that were attributable to sorafenib. Future trials in dogs with cancer are recommended at this dosing schedule to assess the effect of sorafenib administration on anti-tumor efficacy signals and relevant pharmacodynamic target modulation in vivo.

Mathematical modeling and simulation in animal health. Part III: Using nonlinear mixed-effects to characterize and quantify variability in drug pharmacokinetics

A common feature of human and veterinary pharmacokinetics is the importance of identifying and quantifying the key determinants of between-patient variability in drug disposition and effects. Some of these attributes are already well known to the field of human pharmacology such as bodyweight, age, or sex, while others are more specific to veterinary medicine, such as species, breed, and social behavior. Identification of these attributes has the potential to allow a better and more tailored use of therapeutic drugs both in companion and food-producing animals. Nonlinear mixed effects (NLME) have been purposely designed to characterize the sources of variability in drug disposition and response. The NLME approach can be used to explore the impact of population-associated variables on the relationship between drug administration, systemic exposure, and the levels of drug residues in tissues. The latter, while different from the method used by the US Food and Drug Administration for setting official withdrawal times (WT) can also be beneficial for estimating WT of approved animal drug products when used in an extralabel manner. Finally, NLME can also prove useful to optimize dosing schedules, or to analyze sparse data collected in situations where intensive blood collection is technically challenging, as in small animal species presenting limited blood volume such as poultry and fish.

Pharmacokinetics of fentanyl citrate and norfentanyl in Holstein calves and effect of analytical performances on fentanyl parameter estimation

This study describes the pharmacokinetics of intravenously administered (i.v.) fentanyl citrate, and its primary metabolite norfentanyl in Holstein calves. Eight calves (58.6 ± 2.2 kg), aged 3-4 weeks, were administered fentanyl citrate at a single dose of 5.0 μg/kg i.v. Blood samples were collected from 0 to 24 hr. Plasma (nor)fentanyl concentrations were determined using liquid chromatography with mass spectrometry and a lower limit of quantification (LLOQ) of 0.03 ng/ml. To explore the effect of analytical performance on fentanyl parameter estimation, the noncompartmental pharmacokinetic analysis was then repeated with a hypothetical LLOQ value of 0.05 ng/ml. Terminal elimination half-life was estimated at 12.7 and 3.6 hr for fentanyl and norfentanyl, respectively. For fentanyl, systemic clearance was estimated at 2.0 L hr^-1  kg^-1 , volume of distribution at steady-state was 24.8 L/kg and extraction ratio was 0.42. At a hypothetical LLOQ of 0.05 ng/ml fentanyl half-life, volume of distribution at steady-state and clearance were, respectively, of 3.0 hr, 8.8 L/kg and 3.4 L kg^-1  hr^-1 . Fentanyl citrate administered i.v. at 5.0 μg/kg can reach levels associated with analgesia in other species. Pharmacokinetic parameters should be interpreted with respect to LLOQ, as lower limits can influence estimated parameters, such as elimination half-life or systemic clearance and have significant impact on dosage regimen selection in clinical practice.

Network on veterinary medicines initiated by the European Federation For Pharmaceutical Sciences

The European Federation for Pharmaceutical Sciences (EUFEPS) was founded 25 years ago by more than 20 national pharmaceutical societies and faculty members. As a pan-European organization, it brings together pharmaceutical societies as well as academic, industrial and regulatory scientists engaged in drug research and development, drug regulation and education of professionals working in these fields. EUFEPS represents pharmaceutical sciences in Europe and is recognized as such by both the European Commission and the European Medicines Agency. EUFEPS cooperates with the European Federation of Pharmaceutical Industries and other European organizations and maintains global connections with agencies such as the US Food and Drug Administration and the American Association of Pharmaceutical Scientists. EUFEPS has established specified networks forming the basis of its activities. The creation of a Network on Veterinary Medicines is prompted by the manifold problems resulting from the use of veterinary drugs and its inherent interconnections with human medicine, environmental and public health. A long-term goal of this initiative was to expand the spectrum of available therapeutics for use in animals, including the development of innovative delivery systems.

Modeling of Large Pharmacokinetic Data Using Nonlinear Mixed-Effects: A Paradigm Shift in Veterinary Pharmacology. A Case Study With Robenacoxib in Cats

The objective of this study was to model the pharmacokinetics (PKs) of robenacoxib in cats using a nonlinear mixed-effects (NLME) approach, leveraging all available information collected from cats receiving robenacoxib s.c. and/or i.v.: 47 densely sampled laboratory cats and 36 clinical cats sparsely sampled preoperatively. Data from both routes were modeled sequentially using Monolix 4.3.2. Influence of parameter correlations and available covariates (age, gender, bodyweight, and anesthesia) on population parameter estimates were evaluated by using multiple samples from the posterior distribution of the random effects. A bicompartmental disposition model with simultaneous zero and first-order absorption best described robenacoxib PKs in blood. Clearance was 0.502 L/kg/h and the bioavailability was high (78%). The absorption constant point estimate (Ka  = 0.68 h-1 ) was lower than beta (median, 1.08 h-1 ), unveiling flip-flop kinetics. No dosing adjustment based on available covariates information is advocated. This modeling work constitutes the first application of NLME in a large feline population.

Multiple comparison procedure and modeling: a versatile tool for evaluating dose-response relationships in veterinary pharmacology - a case study with furosemide

Congestive heart failure (CHF) is a leading cause of mortality with an increasing prevalence in human and canine populations. While furosemide is a loop diuretic prescribed for the majority of CHF patients to reduce fluid retention, it also activates the renin-angiotensin aldosterone system (RAAS) which further contributes to the accelerated progression of heart failure. Our objective was to quantify the effect of furosemide on diuresis, renin activity (RA), and aldosterone (AL) in dogs, using a combined multiple comparisons and model-based approach (MCP-Mod). Twenty-four healthy beagle dogs were allocated to four treatment groups (saline vs. furosemide 1, 2, and 4 mg/kg i.m., q12 h for 5 days). Data from RA and AL values at furosemide trough concentrations, as well as 24-h Diuresis, were analyzed using the MCP-Mod procedure. A combination of E_max models adequately described the dose-response relationships of furosemide for the various endpoints. The dose-response curves of RA and AL were found to be well in agreement, with an apparent shallower slope compared with 24-h Diuresis. The research presented herein constitutes the first application of MCP-Mod in Veterinary Medicine. Our data show that furosemide produces a submaximal effect on diuresis at doses lower than those identified to activate the circulating RAAS.

Animal Health Modeling & Simulation Society: a new society promoting model-based approaches in veterinary pharmacology

The Animal Health Modeling & Simulation Society (AHM&S) is a newly founded association (2012) that aims to promote the development, application, and dissemination of modeling and simulation techniques in the field of Veterinary Pharmacology and Toxicology. The association is co-chaired by Pr. Johan Gabrielsson (Europe), Pr. Jim Riviere (USA), and secretary Dr. Jonathan Mochel (Switzerland). This short communication aims at presenting the membership, rationale and objectives of this group.