N/A / Thesis / Master of Science (MS)

Few drugs are available to treat congestive heart failure and other cardiac diseases in horses. Pimobendan is an inodilator drug approved as Vetmedin® for treatment of canine cardiac disease. Previous research shows that pimobendan increases heart rate and contractility following intravenous administration in horses. The pharmacokinetics of oral pimobendan have not been investigated in horses. The hypothesis of this study was that pimobendan would be absorbed following oral administration to healthy adult horses and reach concentrations known to be therapeutic in other species. Additional objectives were to compare the absorption of compounded pimobendan capsules (C) and suspension (S) to Vetmedin® (V) and determine the effects of sample site on plasma drug concentrations in a pilot study using two horses. These two horses received C, S, or V (0.5 mg/kg via oral syringe, once) following a minimum 10 hour fast, using a crossover design with a minimum 1-week washout period. Samples were collected simultaneously from lateral thoracic and jugular catheters before and after drug administration at predetermined time points. Differences between formulation and sample site were analyzed by one-way ANOVA. After evaluation of the data from the initial 2 horses, an additional 4 horses received pimobendan, in the form of Vetmedin tablets® (V), in a similar manner. Only jugular samples were collected at the same predetermined time points. Plasma concentrations were determined by ultraperformance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) and pharmacokinetic parameters determined by noncompartmental analysis. No significant differences were noted between formulations or sample site (P < 0.05). Concentrations in compounded formulations were 88%(S) and 90%(C) of label. For V, mean (±SD) maximum plasma concentration (Cmax) was 4.96 ± 2.13 ng/mL at 2.17 ± 0.98 hours, and area under the curve (AUC0-∞) was 22.1 ± 8.8*ng/mL. Concentration of the active metabolite of pimobendan, o-desmethyl-pimobendan, was below the limit of detection (0.07ng/mL) for all samples. At 0.5mg/kg orally, pimobendan plasma concentrations were considerably lower than reported in dogs and other species. There was no evidence of oral transmucosal absorption. Pimobendan was poorly absorbed in horses, regardless of formulation, and appears unlikely to have clinical effects. / Master of Science / The objective of this study was to determine the pharmacokinetics (i.e. evaluation of the drug concentration in the bloodstream over time by means of mathematical modeling) of pimobendan in healthy horses. Pimobendan is a drug used to treat two types of heart disease, myxomatous mitral value disease and dilated cardiomyopathy, in dogs. These diseases often lead to a syndrome, congestive heart failure (CHF), that has high mortality. CHF in horses also has high mortality, and treatments for horses in CHF are based on information from other species. In this study, the FDA approved formulation of pimobendan, Vetmedin®, was administered to six healthy mature horses at a dose of 0.5 mg/kg, which is twice the amount typically administered to dogs in a single dose. Additionally, we gave two of the horses compounded (uniquely formulated) pimobendan capsules and suspension to evaluate their equivalence to Vetmedin® tablets. We serially collected blood samples to measure plasma concentrations of pimobendan after administration of each drug. Our results showed that all three formulations of pimobendan lead to similar blood concentrations in each of the two horses individually. No formulation of pimobendan resulted in plasma levels of pimobendan known to be effective in other species. Overall, the average plasma concentrations of pimobendan in these horses was very low, it was approximately 1/10th the amount reported in canine pharmacokinetic studies of pimobendan. In conclusion, we determined that at a 0.5 mg/kg dose orally, pimobendan is poorly absorbed in horses and seems unlikely to have medical effects.

Thesis (Ph.D.)--University of Adelaide, Dept. of Medicine, 1999. / Appendum consists of last two leaves. Copies of author's previously published articles inserted. Bibliography: leaves 241-283.

Diss. (sammanfattning) Stockholm : Karol. inst., 2006. / Härtill 5 uppsatser.

Congestive heart failure (CHF) is one of the leading causes of hospitalisation, morbidity and mortality in the UK. The incidence and prevalence of CHF is expected to increase due to the aging population and improved survival in heart disease. Exercise has been recognised as a valuable treatment and has proved to be beneficial in CHF. The present study applied the Theory of Planned Behaviour (TPB) and the Commonsense Model of Self-regulation to fitness, daily activity and medication-adherence in elderly patients with CHF. The study was in parallel with a randomised controlled trial of a 3-month exercise programme. A TPB questionnaire was used at baseline and at 3 months. Illness representations were assessed by IPQ-R at baseline. Fitness (measured by 6 minute walk test) and daily activity (measured by an accelerometer) were assessed at baseline, 3 and 6 months. ACEI-adherence (assessed by measuring serum ACE level) was assessed at baseline. The main findings from 81 CHF patients (mean age = 81 years) showed that Subjective norm (SN) was the only predictor of Intention (IN1) at baseline; Attitude, Perceived behavioural control (PBC) were predictors of INT at 3 months; fitness was predicted by PBC at 3 months. The exercise intervention led to significant changes in Attitude and PBe. The finding also indicated that the participants were more likely to attribute their illness to Chance, BiolOgical factors and God. Identity and Illness coherence predicted fitness, and Consequences predicted daily activity. Participants who believed that their illness was chronic or serious were less likely to adhere to ACEI medication. Conclusion: both the TPB and IPQ-R were useful instruments to predict behaviours in elderly patients with CHF. The IPQ-R had a greater predictive power than the TPB in this population. Illness representations may play a role in influencing the formation of intention as background factors.

This thesis examines the retention of best practices by clinicians after the implementation of an integrated care pathway for patients with congestive heart failure. While the literature suggests there are many reasons why the implementation of best practices is difficult, there is little information on the sustainability of best practices once implemented.<p>Using a qualitative research design guided by Rogers theory of Diffusion of Innovations the researcher interviewed seven clinicians who participated in the implementation of the pathway. A thematic analysis revealed several themes that ran throughout participants responses. <p>While the participants indicated they see value in best practices, they also identified barriers to getting that knowledge into practice and keeping it there. A spectrum of factors, including individual autonomy, time, resources, organizational support and the organization of the system all played a role.<p>In the end, participants revealed that although small pieces of the pathway remain in practice, the pathway itself is no longer used by clinicians to manage patients with congestive heart failure.

This thesis examines the retention of best practices by clinicians after the implementation of an integrated care pathway for patients with congestive heart failure. While the literature suggests there are many reasons why the implementation of best practices is difficult, there is little information on the sustainability of best practices once implemented.<p>Using a qualitative research design guided by Rogers theory of Diffusion of Innovations the researcher interviewed seven clinicians who participated in the implementation of the pathway. A thematic analysis revealed several themes that ran throughout participants responses. <p>While the participants indicated they see value in best practices, they also identified barriers to getting that knowledge into practice and keeping it there. A spectrum of factors, including individual autonomy, time, resources, organizational support and the organization of the system all played a role.<p>In the end, participants revealed that although small pieces of the pathway remain in practice, the pathway itself is no longer used by clinicians to manage patients with congestive heart failure.

No description available.

Dissertation (Ph.D.)--Auburn University, 2006. / Abstract. Includes bibliographic references.

Thesis (M.S.)--West Virginia University, 2007. / Title from document title page. Document formatted into pages; contains vii, 36 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 33-36).