Search Results

You are looking at 1 - 8 of 8 items for

  • Author or Editor: Karen M. Young x
  • Refine by Access: All Content x
Clear All Modify Search

Abstract

Objective—To evaluate the efficacy of disinfectant-filled foot mats at reducing tracking of Salmonella enterica and overall bacterial contamination on floors in a veterinary teaching hospital.

Design—Prospective study.

Samples—Bacteria collected from floors before and after placement of disinfectant-filled foot mats.

Procedures—Foot mats filled with a phenolic-based disinfectant were placed at key transition areas in common-use corridors between the large animal hospital (LAH) and small animal hospital in a veterinary medical teaching hospital. Microbiological samples were collected for total bacterial counts and for the presence of S enterica at 14 designated sample sites in the veterinary medical teaching hospital. Samples were collected at regular intervals for 7 months before mat placement and for 13 months after mat placement.

Results—Median numbers of aerobic bacteria isolated before and after disinfectant mat placement were not significantly different for most sites sampled. For 3 of the 4 transition areas between the LAH and connecting common-use corridor, there was a significant difference in median bacterial counts on either side of the threshold. This difference was significant regardless of whether a disinfectant mat was present or not. Salmonella enterica isolates were cultured from several sites in the LAH and sites outside the LAH, irrespective of the presence of a disinfectant mat.

Conclusions and Clinical Relevance—Disinfectant-filled mats may not be uniformly effective in reducing the bacterial load on floors or in reducing mechanical tracking of S enterica from contaminated areas in a veterinary teaching hospital. Further studies are needed to determine effective measures to reduce mechanical transmission of bacteria on footwear in veterinary hospitals.

Restricted access
in Journal of the American Veterinary Medical Association

Abstract

Objective—To compare cardiopulmonary responses during anesthesia maintained with halothane and responses during anesthesia maintained by use of a total intravenous anesthetic (TIVA) regimen in horses.

Animals—7 healthy adult horses (1 female, 6 geldings).

Procedure—Each horse was anesthetized twice. Romifidine was administered IV, and anesthesia was induced by IV administration of ketamine. Anesthesia was maintained for 75 minutes by administration of halothane (HA) or IV infusion of romifidine, guaifenesin, and ketamine (TIVA). The order for TIVA or HA was randomized. Cardiopulmonary variables were measured 40, 60, and 75 minutes after the start of HA or TIVA.

Results—Systolic, diastolic, and mean carotid arterial pressures, velocity time integral, and peak acceleration of aortic blood flow were greater, and systolic, diastolic, and mean pulmonary arterial pressure were lower at all time points for TIVA than for HA. Pre-ejection period was shorter and ejection time was longer for TIVA than for HA. Heart rate was greater for HA at 60 minutes. Minute ventilation and alveolar ventilation were greater and inspiratory time was longer for TIVA than for HA at 75 minutes. The PaCO2 was higher at 60 and 75 minutes for HA than for TIVA.

Conclusions and Clinical Relevance—Horses receiving a constant-rate infusion of romifidine, guaifenesin, and ketamine maintained higher arterial blood pressures than when they were administered HA. There was some indication that left ventricular function may be better during TIVA, but influences of preload and afterload on measured variables could account for some of these differences. (Am J Vet Res 2002;63:1655–1661)

Full access
in American Journal of Veterinary Research

Abstract

Objective—To examine the effects of flunixin meglumine and etodolac treatment on recovery of ischemicinjured equine jejunal mucosa after 18 hours of reperfusion.

Animals—24 horses.

Procedure—Jejunum was exposed to 2 hours of ischemia during anesthesia. Horses received saline (0.9% NaCl) solution (12 mL, IV, q 12 h), flunixin meglumine (1.1 mg/kg, IV, q 12 h), or etodolac (23 mg/kg, IV, q 12 h). Tissue specimens were obtained from ischemic-injured and nonischemic jejunum immediately after ischemia and 18 hours after recovery from ischemia. Transepithelial electric resistance (TER) and transepithelial flux of tritium-labeled mannitol measured mucosal permeability. Denuded villous surface area and mean epithelial neutrophil count per mm2 were calculated. Western blot analysis for cyclooxygenase (COX)-1 and -2 was performed. Pharmacokinetics of flunixin and etodolac and eicosanoid concentrations were determined.

Results—Ischemic-injured tissue from horses treated with flunixin and etodolac had significantly lower TER and increased permeability to mannitol, compared with that from horses treated with saline solution. Epithelial denudation after ischemia and 18 hours after recovery was not significantly different among treatments. Both COX-1 and -2 were expressed in ischemic-injured and nonischemic tissues. Ischemia caused significant upregulation of both COX isoforms. Eicosanoid concentrations were significantly lower in tissues from flunixin and etodolac-treated horses, compared with that from horses treated with saline solution.

Conclusions and Clinical Relevance—Flunixin and etodolac treatment retarded recovery of intestinal barrier function in jejunal mucosa after 18 hours of reperfusion, whereas tissues from horses treated with saline solution recovered baseline values of TER and permeability to mannitol. (Am J Vet Res 2004;65:761–769)

Full access
in American Journal of Veterinary Research

Abstract

Objective—To use Doppler ultrasonography and singlefiber laser Doppler flowmetry (LDF) to evaluate blood flow in the dependent and nondependent hind limbs of anesthetized horses and to evaluate changes in femoral arterial blood flow and microvascular skeletal muscle perfusion in response to administration of phenylephrine hydrochloride or dobutamine hydrochloride.

Animals—6 healthy adult horses.

Procedure—Horses were anesthetized and positioned in left lateral recumbency. Doppler ultrasonography was used to measure velocity and volumetric flow in the femoral vessels. Single-fiber LDF was used to measure relative microvascular perfusion at a single site in the semimembranosus muscles. Phenylephrine or dobutamine was then administered to decrease or increase femoral arterial blood flow, and changes in blood flow and microvascular perfusion were recorded.

Results—Administration of phenylephrine resulted in significant decreases in femoral arterial and venous blood flows and cardiac output and significant increases in mean aortic blood pressure, systemic vascular resistance, and PCV. Administration of dobutamine resulted in significant increases in femoral arterial blood flow, mean aortic blood pressure, and PCV. Significant changes in microvascular perfusion were not detected.

Conclusion and Clinical Relevance—Results suggest that Doppler ultrasonography and single-fiber LDF can be used to study blood flows in the hind limbs of anesthetized horses. However, further studies are required to determine why changes in femoral arterial blood flows were not associated with changes in microvascular perfusion. (Am J Vet Res 2000;61:286–290)

Full access
in American Journal of Veterinary Research

Abstract

Objective—To evaluate the hemodynamic effects of dobutamine hydrochloride (0.5 µg/kg of body weight/min) in halothane-anesthetized horses.

Animals—6 adult Thoroughbred horses.

Procedure—Anesthesia was induced by use of romifidine (100 µg/kg) and ketamine (2.2 mg/kg), IV. Anesthesia was maintained by halothane (end-tidal concentration 0.9 to 1.0%). Aortic, left ventricular, and right atrial pressures were measured, using cathetermounted strain gauge transducers. Cardiac output (CO), velocity time integral, maximal aortic blood flow velocity and acceleration, and left ventricular preejection period and ejection time were measured from aortic velocity waveforms obtained by transesophageal Doppler echocardiography. Velocity waveforms were recorded from the femoral vessels, using Doppler ultrasonography. The time-averaged mean velocity and early diastolic deceleration slope (EDDS) were measured. Pulsatility index (PI) and volumetric flow were calculated. Microvascular perfusion was measured in the semimembranosus muscles by laser Doppler flowmetry. Data were recorded 60 minutes after induction of anesthesia (control) and at 15 and 30 minutes after start of an infusion of dobutamine (0.5 µg/kg/min).

Results—Aortic pressures were significantly increased during the infusion of dobutamine. No change was observed in the indices of left ventricular systolic function including CO. Femoral arterial flow significantly increased, and the PI and EDDS decreased. No change was observed in the femoral venous flow or in microvascular perfusion.

Conclusions and Clinical Relevance—At this dosage, dobutamine did not alter left ventricular systolic function. Femoral blood flow was preferentially increased as the result of local vasodilatation. The lack of effect of dobutamine on microvascular perfusion suggests that increased femoral flow is not necessarily associated with improved perfusion of skeletal muscles. (Am J Vet Res 2000;61:1282–1288)

Full access
in American Journal of Veterinary Research

Abstract

Objective—To determine the accuracy of cytologic diagnosis, compared with histologic diagnosis, in determination of disease in ultrasound-guided fine-needle aspirates of splenic lesions.

Design—Retrospective study.

Sample Population—Splenic specimens from 29 dogs and 3 cats.

Procedures—Records were searched for dogs and cats that had undergone ultrasound-guided splenic aspiration. Criteria for inclusion were ultrasonographic identification of splenic lesions and cytologic and histologic evaluation of tissue from the same lesion. Cytologic samples were obtained by fine-needle aspiration, and histologic specimens were obtained via surgical biopsy, ultrasound-guided biopsy, or necropsy.

Results—Cytologic diagnoses corresponded with histologic diagnoses in 19 of 31 (61.3%) cases and differed in 5 of 31(16.1%) cases, and 1 aspirate was inadequate for evaluation. In 7 of 31 (22.6%) cases, histologic evaluation of tissue architecture was required to distinguish between reactive and neoplastic conditions. On the basis of histologic diagnosis in 14 animals with nonneoplastic conditions, the cytologic diagnosis was correct in 11 cases, not definitive in 2 cases, and incorrect in 1 case. In 17 animals with malignant neoplastic diseases, the cytologic diagnosis was correct in 8 cases, not definitive but consistent with possible neoplasia in 5 cases, and incorrect in 4 cases. Multiple similar-appearing nodules were significantly associated with malignancy, whereas single lesions were more often benign.

Conclusions and Clinical Relevance—Ultrasound-guided aspiration of splenic lesions is a minimally invasive tool for obtaining specimens for cytologic evaluation. Although cytologic diagnoses often reflect histologic results, if missampling or incomplete sampling occurs or tissue architecture is required to distinguish between reactive and neoplastic conditions, accurate diagnosis with fine-needle aspiration may not be possible.

Restricted access
in Journal of the American Veterinary Medical Association

Abstract

Objective—To determine nonenteric sites associated with Escherichia coli isolates in dogs and the antimicrobial susceptibilities of the isolates.

Design—Retrospective study.

Sample Population—17,000 canine specimens.

Procedure—Medical records of 17,000 canine specimens submitted for bacteriologic culture were examined and the number of isolations of E coli was determined. For these cases, records were further examined with respect to body system involvement, sex, concurrent infection with other species of bacteria, and antimicrobial susceptibility.

Results—674 E coli isolates (424 from urine, 62 from the skin, 52 from the respiratory tract, 45 from the ear, 43 from the female reproductive tract, 25 from the male reproductive tract, and 23 from other organ systems) were identified. There was a significantly higher proportion of isolates from urine specimens from spayed females than from sexually intact females or males. Escherichia coli was isolated in pure culture from 65.9% of the specimens. Most E coli isolates were susceptible to norfloxacin (90%), enrofloxacin (87.5%), gentamicin (90.7%), and amikacin (85.9%).

Conclusions and Clinical Relevance—Most nonenteric E coli infections in dogs involve the urinary tract. Amikacin, gentamicin, norfloxacin, and enrofloxacin have the highest efficacy against canine E coli isolates. For E coli isolates from dogs, in vitro susceptibility to commonly used antimicrobial agents has remained fairly stable during the past decade. (J Am Vet Med Assoc 2001;218:381–384)

Restricted access
in Journal of the American Veterinary Medical Association

Abstract

Objective—To assess the suitability of lithium dilution as a method for measuring cardiac output in anesthetized horses, compared with thermodilution and transesophageal Doppler echocardiography.

Animals—6 horses (3 Thoroughbreds, 3 crossbreeds).

Procedure—Cardiac output was measured in 6 anesthetized horses as lithium dilution cardiac output (LiDCO), thermodilution cardiac output (TDCO), and transesophageal Doppler echocardiographic cardiac output (DopplerCO). For the LiDCO measurements, lithium chloride was administered IV, and cardiac output was derived from the arterial lithium dilution curve. Sodium nitroprusside, phenylephrine hydrochloride, and dobutamine hydrochloride were used to alter cardiac output. Experiments were divided into 4 periods. During each period, 3 LiDCO measurements, 3 DopplerCO measurements, and 3 sets of 3 TDCO measurements were obtained.

Results—70 comparisons were made between LiDCO, DopplerCO, and triplicate TDCO measurements over a range of 10 to 43 L/min. The mean (± SD) of the differences of LiDCO – TDCO was –0.86 ± 2.80 L/min; LiDCO = –1.90 + 1.05 TDCO (r = 0.94). The mean of the differences of DopplerCO – TDCO was 1.82 ± 2.67 L/min; DopplerCO = 2.36 + 0.98 TDCO (r = 0.94). The mean of the differences of LiDCO – DopplerCO was –2.68 ± 3.01 L/min; LiDCO = –2.53 + 0.99 DopplerCO (r = 0.93).

Conclusions and Clinical Relevance—These results indicate that lithium dilution is a suitable method for measuring cardiac output in horses. As well as being accurate, it avoids the need for pulmonary artery catheterization and is quick and safe to use. Monitoring cardiac output during anesthesia in horses may help reduce the high anesthetic mortality in this species. (Am J Vet Res 2000;61:731–737)

Full access
in American Journal of Veterinary Research