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排序方式: 共有298条查询结果,搜索用时 328 毫秒
61.
Noel Clancey Shelley Burton Barbara Horney Allan MacKenzie Andrea Nicastro Etienne Côté 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2009,38(3):299-305
Background: Cardiac disease has the potential to alter platelet function in dogs. Evaluation of platelet function using the PFA‐100 analyzer in dogs of multiple breeds and with a broad range of cardiac conditions would help clarify the effect of cardiac disease on platelets. Objectives: The objective of this study was to assess differences in closure time (CT) in dogs with cardiac disease associated with murmurs, when compared with that of healthy dogs. Methods: Thirty‐nine dogs with cardiac murmurs and turbulent blood flow as determined echocardiographically were included in the study. The dogs represented 23 different breeds. Dogs with murmurs were further divided into those with atrioventricular valvular insufficiency (n=23) and subaortic stenosis (n=9). Fifty‐eight clinically healthy dogs were used as controls. CTs were determined in duplicate on a PFA‐100 analyzer using collagen/ADP cartridges. Results: Compared with CTs in the control group (mean±SD, 57.6±5.9 seconds; median, 56.5 seconds; reference interval, 48.0–77.0 seconds), dogs with valvular insufficiency (mean±SD, 81.9±26.3 seconds; median, 78.0 seconds; range, 52.5–187 seconds), subaortic stenosis (71.4±16.5 seconds; median, 66.0 seconds; range, 51.5–95.0 seconds), and all dogs with murmurs combined (79.6±24.1 seconds; median, 74.0 seconds; range, 48.0–187 seconds) had significantly prolonged CTs (P<.01). Conclusions: The PFA‐100 analyzer is useful in detecting platelet function defects in dogs with cardiac murmurs, most notably those caused by mitral and/or tricuspid valvular insufficiency or subaortic stenosis. The form of turbulent blood flow does not appear to be an important factor in platelet hypofunction in these forms of cardiac disease. 相似文献
62.
Rebecca L. Stepien DVM MS Keith G. Benson DVM Lisa J. Wenholz BS 《Veterinary radiology & ultrasound》2000,41(5):452-456
M-mode and Doppler echocardiographic values were obtained from 30 normal adult ferrets (14 neutered females, 13 neutered males, 3 intact males) sedated with an intramuscular combination of ketamine hydrochloride and midazolam. Routine M-mode measurements of the left and right ventricle, left atrium (LA) and aorta (AO) and Doppler measurements of aortic and pulmonic outflow, and mitral inflow were recorded. The following values were calculated: LA:AO diameter, ratio of peak E: peak A wave velocity (E:A ratio) for mitral inflow, and stroke volume (SV), cardiac output (CO) and cardiac index (CI) for both pulmonary and aortic outflow tracts. Maximal aortic velocities (AOmax) and velocity-time integral values (AO VTI) were significantly less than corresponding pulmonary outflow tract values (PAmax, PA VTI) but there was no difference in calculated values for SV, CO or CI. Calculated CO values were in the range expected based on the size of the species. Difficulties in aligning the aortic outflow tract for Doppler imaging may make pulmonary outflow Doppler values more consistent for use in estimating volume flow in ferrets. 相似文献
63.
Robert A. Holmes DVM MS Fred G. Smith DVM PhD Robert E. Lewis DVM MS Dennis M. Kern PhD 《Veterinary radiology & ultrasound》1985,26(3):98-101
Cardiac mensuration was done on thoracic radiographs of Beagles to determine the effects of rotation on the cardiac silhouette in dorsal recumbency. As the thorax became more rotated, surfaces of the heart not normally seen were projected, making interpretation of cardiac changes unreliable. A positioning standard based on the relationship of the dorsal spinous processes to the vertebral body was developed. If the tips of the dorsal spinous processes were within the bounds of the vertebral bodies, the radiographs were suitable for cardiac interpretation. If the tips of the dorsal spinous processes were outside the bounds of the vertebral bodies, there was enough rotation to make interpretation unreliable. A microcomputer, digitizer pad, and a BASIC language program were used to input, store, and calculate the various cardiac mensuration parameters. 相似文献
64.
PHILIP D. KOBLIK DVM MS WILLIAM J. HORNOF DVM MS 《Veterinary radiology & ultrasound》1987,28(5):177-180
First-pass nuclear angiocardiography was performed on 13 normal horses and 5 horses with confirmed left-to-right ventricular septal defects. Two methods of analyzing the ensuing pulmonary time-activity histograms for shunt recirculation through the lungs were evaluated: (1) pulmonary-to-systemic blood flow ratio (QP:QS), based on gamma variate modeling of the lung histogram, and (2) a simple count-ratio method (C2:C1). Normal values were QP:QS=1.17±0.04 and C2:C1=0.40±0.07. Values for the five horses with left-to-right shunts were QP:QS=2.94±0.13 and C2:C1=0.76±0.11. Both parameters showed significant differences (unpaired t -test; p <0.005) between the two groups, although separation was better with QP:QS. 相似文献
65.
Seung-Gon Lee DVM MS Hyeong-Sun Moon DVM Changbaig Hyun DVM PhD 《Journal of Veterinary Emergency and Critical Care》2008,18(4):362-369
Objective: To evaluate the efficacy and safety of biphasic (BP) defibrillation in toy breed dogs (<5 kg of body weight).
Design: Prospective, clinical experimental study.
Setting: Veterinary teaching hospital.
Animals: Five dogs (pilot study) and 10 dogs (comparison study of biphasic versus monophasic defibrillation).
Measurements and main results: The efficacy of defibrillation was compared by estimating E80 (80% probability of successful defibrillation) after biphasic (BP) and monophasic (MP) defibrillations. The E80 for BP defibrillation was 7.24±1.33 J (2.24±0.41 J/kg) and 10.24±1.34 J (3.18±0.12 J/kg) for MP defibrillation. BP waveform required 30% less shock energy for a successful defibrillation. In order to compare the safety of defibrillation, we evaluated changes in cardiac biomarkers, electrocardiogram, echocardiographical left ventricular index, and aortic pressure during and after BP and MP defibrillation. All dogs treated by either BP or MP defibrillation survived. Pulseless electrical activity occurred in 2 of 5 dogs during MP defibrillation. The levels of cardiac biomarkers were elevated and sustained for longer periods in the MP defibrillation group. Electrocardiographic changes (e.g., QT prolongation, the time to return to an isoelectric ST segment after shocks) were more severe and longer in the MP defibrillation group. In addition, overall left ventricular cardiac performance was severely depressed in the MP group compared with the BP group.
Conclusion: Our findings suggest that BP defibrillation is more effective and safer than MP defibrillation. We determined the acceptable shock energy to be 2–4 J/kg for toy breed dogs. 相似文献
Design: Prospective, clinical experimental study.
Setting: Veterinary teaching hospital.
Animals: Five dogs (pilot study) and 10 dogs (comparison study of biphasic versus monophasic defibrillation).
Measurements and main results: The efficacy of defibrillation was compared by estimating E80 (80% probability of successful defibrillation) after biphasic (BP) and monophasic (MP) defibrillations. The E80 for BP defibrillation was 7.24±1.33 J (2.24±0.41 J/kg) and 10.24±1.34 J (3.18±0.12 J/kg) for MP defibrillation. BP waveform required 30% less shock energy for a successful defibrillation. In order to compare the safety of defibrillation, we evaluated changes in cardiac biomarkers, electrocardiogram, echocardiographical left ventricular index, and aortic pressure during and after BP and MP defibrillation. All dogs treated by either BP or MP defibrillation survived. Pulseless electrical activity occurred in 2 of 5 dogs during MP defibrillation. The levels of cardiac biomarkers were elevated and sustained for longer periods in the MP defibrillation group. Electrocardiographic changes (e.g., QT prolongation, the time to return to an isoelectric ST segment after shocks) were more severe and longer in the MP defibrillation group. In addition, overall left ventricular cardiac performance was severely depressed in the MP group compared with the BP group.
Conclusion: Our findings suggest that BP defibrillation is more effective and safer than MP defibrillation. We determined the acceptable shock energy to be 2–4 J/kg for toy breed dogs. 相似文献
66.
Erik H. Hofmeister DVM Brian F. Thompson MS Benjamin M. Brainard VMD DACVECC DACVA Samantha Kegge DVM Stephanie Kube DVM DACVIM Christine M. Egger DVM MVSc DACVA CVA Carl Jehn DVM Brad Green DVM 《Journal of Veterinary Emergency and Critical Care》2008,18(2):142-152
Objective: To document the clinical practice of cardiopulmonary–cerebral resuscitation (CPCR) among academic veterinarians. Design: Survey. Setting: Eight colleges of veterinary medicine in the United States. Subjects: Two hundred and one academic veterinarians. Interventions: The survey was distributed by hand by the authors into the mailboxes of small animal faculty, residents, and interns. Demographic variables, questions regarding number of cardiopulmonary arrests (CPA) supervised and number successful, do not attempt resuscitation discussions, and Likert‐style questions about client presence during CPCR, appropriateness of CPCR, and CPCR decision‐making were included. Multiple linear regression models were constructed to determine the effect of multiple questions on different target variables of interest. Measurements and main results: Numerous differences were noted based on institution, gender, specialty, and position. Most institutions did not have a standard resuscitation consent form. Most respondents believed the client, house officer, and senior clinician should determine whether to perform resuscitation or not. Quality of life was the most significant determinant of whether to resuscitate or not, followed by long‐term prognosis, then short‐term prognosis. Conclusions: Veterinarians differ in many aspects of their approach to CPA and resuscitation. Creating consensus within the veterinary profession would benefit client service and patient care. 相似文献
67.
Ada To Eric T. Hostnik Jaylyn D. Rhinehart Brian A. Scansen 《Veterinary radiology & ultrasound》2019,60(2):145-158
Pulmonary valve stenosis (PS) is one of the most commonly diagnosed congenital heart defects in dogs. Currently, transthoracic echocardiography (TTE) is the standard modality used to evaluate PS. Image acquisition by TTE can be challenging in some brachycephalic breeds of dogs. The use of echocardiographic‐gated CT angiography (ECG‐gated CTA) in veterinary medicine is limited. This retrospective method comparison study investigated right and left ventricular outflow diameters by sedated ECG‐gated CTA and unsedated TTE in 14 brachycephalic dogs with PS and 12 brachycephalic dogs without PS. Measurements of ventricular outflow structures were made in early systole and end diastole for both modalities and then compared for significance between systolic and diastolic phases, as well as between the two modalities. Ratios of the pulmonary trunk diameter to the aorta at different locations (aortic valve, aortic annulus, and ascending aorta) and in different planes (transverse, sagittal) were compared between dogs with PS and without PS, as well as within dogs, by both TTE and ECG‐gated CTA. Transthoracic echocardiography and ECG‐gated CTA both detected significantly greater pulmonary trunk to aorta ratios in dogs with PS at all aortic locations (P < 0.05). Pulmonary valve to aortic valve ratios were significantly smaller in dogs with PS (P < 0.05). Pulmonary trunk to aorta and pulmonary valve to aorta ratios were achieved with good anatomic detail using ECG‐gated CTA. Ratios of the pulmonary trunk and pulmonary valve relative to the aorta may be useful to evaluate for PS using a modality that is underutilized for cardiac assessment. 相似文献
68.
Elizabeth R. Carvalho Tatiana Champion Francielli Ambrosini Gabrieli A. da Silva Gabrielle C. Freitas Ricardo G. D’Otaviano de Castro Vilani 《Veterinary anaesthesia and analgesia》2019,46(1):43-54
Objective
To investigate the effects of a low dose of dexmedetomidine (DEX) followed by constant rate infusion (CRI) and reversal with atipamezole on systolic and diastolic functions in isoflurane-anesthetized healthy cats.Study design
Prospective cohort study.Animals
A group of 11 client-owned adult cats.Methods
Baseline transthoracic echocardiography (TTE) was performed, followed by intramuscular (IM) administration of DEX (5 μg kg?1). After 10 minutes, sedation was scored, adverse effects were recorded and another TTE performed. Approximately 40 minutes after DEX administration, anesthesia was induced by isoflurane mask and maintained with 1.2% end-tidal isoflurane and DEX CRI (1 μg kg?1 hour?1) for 80 minutes. Physiological variables were recorded every 10 minutes, and TTE was repeated 10, 30 and 60 minutes after the start of anesthesia. CRI was stopped, atipamezole (30 μg kg?1) was administered IM and a final TTE was performed after 10 minutes. Repeated measures over time were submitted to one-way analysis of variance or Kruskal–Wallis test according to data distribution; significance was assumed at p < 0.05.Results
After DEX premedication, mild sedation and a slight but significant increase in systolic arterial pressure occurred, and vomiting was a common adverse effect. The cardiac output (CO) and heart rate decreased during anesthesia, with no changes after administration of atipamezole. Trivial valvular insufficiencies were commonly seen after DEX premedication and during CRI. Myocardial radial and longitudinal systolic functions were not affected by sedation or by anesthesia. The late phase of diastole on both right and left ventricles was affected by isoflurane–DEX CRI. Global left ventricular myocardial performance was not impaired.Conclusions
and clinical relevance Decreased CO and late diastolic impairment were observed in healthy cats administered a low dose of DEX for premedication followed by anesthesia with isoflurane and DEX CRI. 相似文献69.
70.
Evaluation of agreement and trending ability between transpulmonary thermodilution and calibrated pulse contour and pulse power cardiac output monitoring methods against pulmonary artery thermodilution in anesthetized dogs 下载免费PDF全文