Relationship between tricuspid annular plane systolic excursion, fluid responsiveness and volume status in hospitalised dogs with circulatory abnormalities.

AIMS: To evaluate the echocardiographic variable tricuspid annular plane systolic excursion normalised to body weight (TAPSEnorm) as a predictor of fluid responsiveness in hospitalised dogs with haemodynamic and tissue perfusion alterations and to investigate the association of left ventricular internal diameter in diastole normalised to body weight (LVIDdN) and aortic velocity time integral (VTIAo) with TAPSEnorm. METHODS: A single-centre, prospective study was carried out in a cohort of spontaneously breathing dogs, hospitalised for any reason, with severe haemodynamic and tissue perfusion alterations. The echocardiographic variables TAPSEnorm, LVIDdN, and VTIAO were measured. A bolus of 30 mL/kg of lactated Ringer's solution was administered and then VTIAo was subsequently remeasured. Patients were classified as fluid responsive if VTIAo increased by ≥15% after fluid expansion, or non-responsive if VTIAo increased by <15% after fluid expansion. The area under the receiver operating characteristic (AUROC) curve was generated to evaluate the ability of TAPSE to predict fluid responsiveness. Simple regression models were used to assess the linear relationship between TAPSEnorm and LVIDdN or VTIAO. RESULTS: TAPSEnorm was lower in fluid responsive dogs (mean 0.57 (95% CI = 0.50-0.64) cm/kg) compared to non-responsive dogs (mean 0.76 (95% CI = 0.62-0.90) cm/kg). The AUROC for TAPSEnorm was 0.827 (95% CI = 0.65-1.00). The optimal cut-off point was 0.76 with sensitivity of 80 (95% CI = 28.4-99.5)% and specificity of 86.7 (95% CI = 69.3-99.2)%, positive predictive value of 50 (95% CI = 15.7-84.3)% and negative predictive value of 96.3 (95% CI = 81-99.9)%. A monotonic linear relationship was observed between TAPSEnorm and LVIDdN (p<0.001) and between TAPSEnorm and VTIAo (p=0.001). CONCLUSIONS AND CLINICAL RELEVANCE: TAPSEnorm could be useful in determining those dogs that are likely to respond to a fluid bolus from those that are likely to be non-responsive. Additionally, a positive linear association between the LVIDdN and the TAPSEnorm suggests that TAPSEnorm decreases at lower preload values. The present study results suggest that TAPSEnorm could be a valuable tool for evaluating blood volume status and fluid responsiveness in hospitalised dogs.Abbreviations: AUROC: Area under the receiver operating characteristic; CO: Cardiac output; ICC: Intraclass correlation coefficient; LVIDd: Left ventricular internal diameter in diastole; LVIDdN: Left ventricular internal diameter in diastole normalised to body weight; TAPSE: Tricuspid annular plane systolic excursion; TAPSEnorm: Tricuspid annular plane systolic excursion normalised to body weight; VTIAo: Aortic velocity time integral.

Angiotensin-converting enzyme inhibitors in preclinical myxomatous mitral valve disease in dogs: systematic review and meta-analysis.

OBJECTIVES: To determine the efficacy and adverse events of the administration of angiotensin--converting enzyme inhibitors for the management of preclinical myxomatous mitral valve disease in dogs. MATERIALS AND METHODS: A compre- hensive search using Pubmed/MEDLINE, LILACS and CAB abstracts databases was performed. Ran- domised clinical trials that assessed efficacy and adverse events of angiotensin-converting enzyme inhibitors for the management of preclinical myxomatous mitral valve disease in dogs were included. Certainty of evidence was rated using GRADE methods. RESULTS: Four randomised clinical trials were included. While safe, angiotensin-converting enzyme inhibitors administration to dogs with myxomatous mitral valve disease and cardiomegaly results in little to no difference in the risk of development congestive heart failure (high certainty of evidence; relative risk: 1.03; 95% confidence interval: 0.87 to 1.23) and may result in little to no difference in cardiovascular-related (low certainty of evidence; relative risk: 1.01; 95% confidence interval: 0.54 to 1.89) and all-cause mortality (low certainty of evidence; relative risk: 0.93; 95% confidence interval: 0.63 to 1.36). Administration of angiotensin-converting enzyme inhibitors to dogs with myxomatous mitral valve disease without cardiomegaly may result in a reduced risk of congestive heart failure development. However, the range in which the actual effect for this outcome may be, the "margin of error," indicates it might also increase the risk of congestive heart failure development (low certainty of evidence; relative risk: 0.86; 95% confidence interval: 0.54 to 1.35). CLINICAL SIGNIFICANCE: Administration of angiotensin-converting enzyme inhibitors to dogs with -preclinical myxoma- tous mitral valve disease and cardiomegaly results in little to no difference in the risk of the develop- ment of congestive heart failure and may result in little to no difference in -cardiovascular-related and all-cause mortality. The certainty of evidence of the efficacy of angiotensin-converting enzyme inhibi- tors administration to dogs without cardiomegaly was low.

Comparative pharmacokinetics of intravenous cephalexin in pregnant, lactating, and nonpregnant, nonlactating goats.

The aims of this study were to describe and compare the pharmacokinetics of a single dose of cephalexin (10 mg/kg) after its intravenous (i.v.) administration to five goats in three different physiological status: nonpregnant nonlactating (NPNL), pregnant (P) and nonpregnant lactating (L). Blood samples were collected at predetermined times, and plasma concentrations of cephalexin were measured by microbiological assay. Relevant pharmacokinetic parameters were calculated using noncompartmental analysis. Statistical comparison was performed applying the nonparametric anova. No significant differences were found for cephalexin pharmacokinetic parameters between the L and the NPNL group. Median V(dss) was significantly lower in pregnant goats (0.09 [0.07-0.10] L/kg) compared with NPNL goats (0.16 [0.14-0.49] L/kg). Median total Cl and V(dz) were significantly lower in pregnant goats (0.25 [0.19-0.29] L/h·kg and 0.11 [0.10-0.13] L/kg, respectively) than in lactating goats (0.40 [0.32-0.57] L/h·kg and 0.20 [0.14-0.23] L/kg, respectively). Median AUC(0-∞) was significantly higher in pregnant goats (37.79 [34.75-52.10] µg·h/mL) than in lactating goats (25.11 [17.44-31.14] µg·h/mL). Our study showed that even though some pharmacokinetic parameters of cephalexin are altered in pregnant and lactating goats, these differences are unlikely to be of clinical importance; therefore, no dose adjustment would be necessary during pregnancy and lactation.

Pharmacokinetics of erythromycin after the administration of intravenous and various oral dosage forms to dogs.

The purpose of this study was to describe and compare the pharmacokinetic properties of different formulations of erythromycin in dogs. Erythromycin was administered as lactobionate (10 mg/kg, IV), estolate tablets (25 mg/kg p.o.) and ethylsuccinate tablets or suspension (20 mg/kg p.o.). After intravenous (i.v.) administration, the principal pharmacokinetic parameters were (mean +/- SD): AUC((0-infinity)) 4.20 +/- 1.66 microg x h/mL; C(max) 6.64 +/- 1.38 microg/mL; V(z) 4.80 +/- 0.91 L/kg; Cl(t) 2.64 +/- 0.84 L/h.kg; t((1/2)lambda) 1.35 +/- 0.40 h and MRT 1.50 +/- 0.47 h. After the administration of estolate tablets and ethylsuccinate suspension, the principal pharmacokinetic parameters were (mean +/- SD): C(max), 0.30 +/- 0.17 and 0.17 +/- 0.09 microg/mL; t(max), 1.75 +/- 0.76 and 0.69 +/- 0.30 h; t((1/2)lambda), 2.92 +/- 0.79 and 1.53 +/- 1.28 h and MRT, 5.10 +/- 1.12 and 2.56 +/- 1.77 h, respectively. The administration of erythromycin ethylsuccinate tablets did not produce measurable serum concentrations. Only the i.v. administration rendered serum concentrations above MIC(90) = 0.5 microg/mL for 2 h. However, these results should be cautiously interpreted as tissue erythromycin concentrations have not been measured in this study and, it is recognized that they can reach much higher concentrations than in blood, correlating better with clinical efficacy.