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81.
Gregory B. Daniel DVM MS Kyle K. Kerstetter DVM Jill E. Sackman DVM PhD Janice M. Bright MS DVM Dorothy Schmidt BS 《Veterinary radiology & ultrasound》1998,39(5):459-469
Radionuclide ventriculography has been used in humans to evaluate valvular incompetency. The stroke volume ratio, derived from the radionuclide ventriculogram, is used to quantify the severity of mitral regurgitation (MR). Previous studies conducted in humans have shown that left to right stroke volume ratio increases as the severity of MR increases. In this study, we evaluated radionuclide ventriculography as a noninvasive method to detect MR in dogs with surgically created mitral insufficiency. Six male and three female adult, conditioned mongrel dogs were used. Scintigraphic studies were performed prior to and 4 weeks after surgically created MR. Because of the overlap of the left and right ventricles when viewed from a left lateral position, we combined data from a first-pass radionuclide angiocardiogram with the radionuclide ventriculogram to obtain a corrected stroke volume ratio. Blood flow transit parameters were also derived from the first-pass radionuclide angiocardiogram. Standard left ventricular functional indices were also measured from the radionuclide ventriculogram. On the left lateral view of the heart, 25 to 30% of the right ventricular volume overlaps the left ventricle. After correcting for the overlap, the stroke volume ratio of normal dogs was 1.17±0.178 (mean±SD), which increased to 2.06±0.41 (mean±SD) (p<.001) 4 weeks after creation of MR. The was no significant change in left ventricular ejection fraction or peak rate of ejection following MR. The transit times of blood through the left ventricle were measured from the first-pass radionuclide angiocardiogram and were expressed as half-time clearance, peak clearance rate, and time to peak clearance rate. The baseline half-time clearance was 2.07±0.71 s (mean±SD), which increased to 6.70±4.89 s (mean±SD) (p=.02) after creation of MR. The baseline peak clearance rate was 49.75±8.96 cts/s (mean±SD), which decreased to 23.12±6.84 cts/s (mean±SD) (p<.001) after creation of MR. Stroke volume ratios significantly increased following creation of MR. Blood flow transit through the left ventricle slowed following creation of MR. The variability of these parameters were small in the baseline studies, suggesting these techniques may be clinically useful to gauge the severity of MR in dogs. 相似文献
82.
Paul Y. Barthez DVM William J. Hornof DVM MS Larry D. Cowgill DVM PhD Larry A. Neal BS Paul Mickel 《Veterinary radiology & ultrasound》1998,39(5):470-474
The scintigraphically measured percentage dose uptake of 99m Tc-DTPA by the kidneys and the plasma clearance of 99m Tc-DTPA have been reported to correlate well with inulin clearance. These two parameters were evaluated in seven dogs with known or suspected naturally occurring renal disease and compared to simultaneously measured renal inulin clearance. Correlation between inulin clearance and the 99m Tc-DTPA plasma clearance was better ( p =.0016) than the correlation between the percentage DTPA uptake by the kidney. It was concluded that measurement of 99m Tc-DTPA plasma clearance is a more accurate method to estimate global glomerular filtration rate (GFR) than the percentage kidney uptake. 相似文献
83.
Strength Characteristics and Failure Modes of Locking-Loop and Three-Loop Pulley Suture Patterns in Equine Tendons 总被引:1,自引:0,他引:1
HENRY W. JANN DVM MS DiplomateACVs LARRY E. STEIN PhD JAMES K. GOOD PhD 《Veterinary surgery : VS》1990,19(1):28-33
Size 3-0 polydioxanone was used as a single strand, single braid (3 strands), or double braid (6 strands) to create six suture material-pattern combinations for equine tenorrhaphy: single-strand locking loop, single-braid locking loop, double-braid locking loop, single-strand three-loop pulley, single-braid three-loop pulley, and double-braid three-loop pulley. Maximum load to failure for the single-strand locking loop (46.1 +/- 2.9 newtons [N]) was less than for all other sutures (range, 103-155 N). The load required to form a 2 mm gap between tendon ends was greater for the single-braid three-loop pulley (66.7 +/- 6.9 N) and double-braid three-loop pulley (85.4 +/- 17.7 N) than any other sutures. The load required to produce a 10 mm gap was least for the single-strand locking loop (34.3 +/- 3.9 N) and greatest for the double-braid three-loop pulley (131.5 +/- 27.5 N). Gap between tendon ends at maximum load was greater for the single-braid (18.1 +/- 0.9 mm) and double-braid (19.2 +/- 2.2 mm) locking loops than for any other sutures. Suture material broke in 53% of the locking-loop tests but in only 17% of the three-loop pulley tests. Tendon matrix disruption accounted for 43% of the locking-loop failures and 77% of the three-loop pulley failures. The three-loop pulley pattern provided more support, less tendon distraction, and less tendon matrix constriction and distortion than the locking-loop pattern.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
84.
Total gastric emptying time was determined in nine mongrel dogs using a barium meal contrast procedure. Within the group, total gastric emptying time ranged from 7.0–15.0 hours. Comparison of the population mean showed a statistical difference (p − 0.01) from previously published values. Individual dogs showed consistent total gastric emptying time over three trials. The technique can be used to test the effect of a procedure on total gastric emptying time when a normal value has been established for the dog. Due to the wide range of normal values observed, evaluation of clinical patients could be difficult unless there is a gross abnormality in function. 相似文献
85.
J. T. BLACKFORD dvm MS D. O. GOBLE dvm DiplomateACVS R. W. HENRY dvm PhD D. R. GEISER dvm J. P. HELD DrMedVet 《Veterinary surgery : VS》1985,14(4):287-294
A modified bone-flap technique was used to expose space occupying lesions that involved the conchofrontal sinus, ethmoturbinates, and caudal nasal cavity in five horses. The most common clinical findings were chronic nasal discharge and upper airway obstruction. Surgical intervention was based on endoscopic and radiographic interpretation. The triangulated bone-flap technique increased surgical exposure to the conchofrontal sinus by almost twice the area observed in previously described surgical techniques. The major advantages were that this technique allowed excellent visualization, thorough palpation, and surgical manipulation within the sinus and associated structures. Complications were minimal. One horse was euthanized 1 month postoperatively with recurrence and spread of a mycotic granuloma. The technique extended the usefulness of the other four horses in a 9 to 24 month follow-up period, although the obstructing lesion recurred after 2 years in one of the four horses. 相似文献
86.
Laparoscopic Cryptorchid Castration in Standing Horses 总被引:1,自引:0,他引:1
DEAN A. HENDRICKSON DVM MS Dipiomate ACVS DAVID G. WILSON DVM Dipiomate ACVS 《Veterinary surgery : VS》1997,26(4):335-339
Objective — This article describes a new technique for laparoscopic cryptorchid castration in standing horses. Study Design — Prospective study. Animals or Sample Population — Eight horses aged 11 months to 3 years and weighing between 300 and 643 kg. Methods — Food was withheld for 24 to 36 hours, and then horses were sedated with detomidine HC1 (0.02 to 0.03 mg/kg) and butorphanol tartrate (0.02 mg/kg). The paralumbar fossa region was desensitized with 2% mepivacaine in an inverted “L” pattern and caudal epidural anesthesia was administered with either xylazine (0.18 mg/kg diluted to 10 to 15 mL with 0.9% sodium chloride) or a combination of 2% mepivacaine and xylazine (0.18 mg/kg). Initial laparoscopic exploration was performed from the left flank; in three horses, right flank laparoscopy was needed to complete the procedure. The spermatic cord was ligated within the abdomen with one or two sutures of 0 polydioxanone suture, and the testis or testes removed through a flank incision. Results — In five horses with no palpably descended testes, standing laparoscopy was the only procedure performed, whereas in two horses, the abdominal testis was removed laparoscopically, and the descended testis was removed under short acting anesthesia. In one horse, with nonpalpable testes, it was determined by laparoscopic observation that the testes were in the inguinal canal, and castration was performed under general anesthesia. No surgical or postoperative complications were noted. The right side of the abdomen, and especially the right vaginal ring, could be easily observed from the left side by passing the laparoscope through a small perforation in the mesocolon of the descending colon or by elevating the descending colon with an instrument or by use of an arm in the rectum. Conclusions — The standing laparoscopic approach combined with or without short-acting anesthesia to remove the descended testis is easily performed. Clinical Relevance — This approach will provide surgeons with another option to castrate cryptorchid stallions. 相似文献
87.
BRENT A. HAGUE DVM CLIFFORD M. HONNAS DVM Dipiomate ACVS R. BRUCE SIMPSON DVM MS Dipiomate ACVM JOHN G. PELOSO DVM MS Dipiomate ACVS 《Veterinary surgery : VS》1997,26(2):121-125
Objective —This study evaluates skin bacterial flora before and after aseptic preparation of clipped and nonclipped arthrocentesis sites in horses. Study Design —The hair over one midcarpal joint and one distal interphalangeal joint on each horse was clipped. The contralateral joint served as the nonclipped comparison. Animals or Sample Population —Twelve adult horses. Methods —A prescrub sample for microbial culture was taken from the dorsal surface of all four joints for each horse. Each site was aseptically prepared with povidone iodine and 70% alcohol, followed by postscrub sampling for microbial culture. Colony forming units (CFUs) were determined for each sample, 24 hours after inoculation of blood agar plates. Results —There was no significant difference (P >.05) in number of postscrub CFUs between clipped and nonclipped skin over the midcarpal or distal interphalangeal joints. Percent bacterial reduction (mean ± SD%) after aseptic preparation differed significantly (P=.02) between clipped (99.8 ±.003%) and nonclipped (96.2 ±.05%) skin at the midcarpal joint, but not at the distal interphalangeal joint (clipped, 98.5 ±.03% and nonclipped, 97.8 ± 0.21%). There was a significant difference (P=.009) in number of prescrub CFUs obtained from clipped and nonclipped skin for the midcarpal joint. There was no significant difference in number of prescrub CFUs between clipped and nonclipped skin at the distal interphalangeal joint. Bacteria isolated from both clipped and nonclipped skin sampled postscrub included Bacillus sp, nonhemolytic Staphylococcus sp, and Micrococcus sp. Conclusions —The presence of hair over the midcarpal and distal interphalangeal joints does not appear to inhibit the ability of antiseptics to effectively reduce bacterial flora to an acceptable level for arthrocentesis. Clinical Relevance —Aseptic preparation of the skin over the midcarpal and distal interphalangeal joints can be accomplished without hair removal in horses. 相似文献
88.
KENNETH E. BARTELS dvm MS ROGER C. PENWICK VMD LYN J. FREEMAN dvm RICHARD L. LOWERY PhD TOM ALEXANDER BS KENT APPLEMAN BS CATHRYN BLOUNT BS 《Veterinary surgery : VS》1985,14(4):310-318
Eight synthetic casting materials were evaluated with respect to tensile and fatigue strengths, exothermicity (evolution of heat during polymerization), permeability (porosity), radiolucency, and cost. Strength determination for a five-layer sample included measurement of the ultimate load at which a material failed, the ability to absorb energy, and the stiffness a material possessed after application of a cyclic stress. Results indicated that Vet Cast was superior with respect to tensile and fatigue strengths. The exothermic reaction associated with the "curing" or polymerization process was evaluated and not considered excessive although Ultra Cast attained a temperature of 48.0°C and was uncomfortable to handle during application. Permeability was determined. Delta Lite and Hexcelite NS were the most permeable materials and dried more rapidly and thoroughly after immersion than the other casting materials. Hexcelite NS was considered the least radiolucent material and was the most expensive material studied. Each of the synthetic casting materials demonstrated superiority in one or more of the categories tested. No one product demonstrated consistent superiority in criteria appropriate for clinical application. 相似文献
89.
MARY ANN NIEVES DVM MS PATRICIA HARTWIG DVM JOANN M. KINYON BS MS DEAN H. RIEDESEL DVM PhD Diplomate ACVA 《Veterinary surgery : VS》1997,26(1):26-32
Objective — This study evaluates the association between dental procedures and bacteremia in dogs, including a comparison of bacteria isolated from plaque and blood, severity of the bacteremia versus the severity of dental disease, and the longevity of bacteremia.
Study Design — Bacteria cultured from the blood over time were compared with those isolated from the plaque and crevicular fluid and in relation to severity of dental disease.
Animals or Sample Population — Twenty adult greyhounds.
Methods — Blood samples were collected for culture before induction of general anesthesia, immediately after intubation, 20 minutes after initiation of the dental procedure, and at 10-minute intervals until 10 minutes after the dental procedure was completed. Samples of plaque were taken for microbiological culture.
Results — Sixty to ninety percent of the bacterial genera isolated from the plaque were present in the blood. Dogs classified according to severity of dental disease showed no difference in the total number of different species or number of different Gram-negative, Gram-positive, or anaerobic bacteria isolated from plaque or blood (P <.05). Bacteremia was present in all of the dogs studied, within 40 minutes from the initiation of the dental procedure, regardless of the severity of oral disease.
Conclusions — Gram-negative, Gram-positive, and anaerobic bacteria are present in blood during dental procedures; the bacteremia can persist beyond the dental procedure, and is not associated with the severity of dental disease.
Clinical Relevance — The nature and extent of bacteremia occuring during routine dental procedures is important in understanding a potential risk to dogs. 相似文献
Study Design — Bacteria cultured from the blood over time were compared with those isolated from the plaque and crevicular fluid and in relation to severity of dental disease.
Animals or Sample Population — Twenty adult greyhounds.
Methods — Blood samples were collected for culture before induction of general anesthesia, immediately after intubation, 20 minutes after initiation of the dental procedure, and at 10-minute intervals until 10 minutes after the dental procedure was completed. Samples of plaque were taken for microbiological culture.
Results — Sixty to ninety percent of the bacterial genera isolated from the plaque were present in the blood. Dogs classified according to severity of dental disease showed no difference in the total number of different species or number of different Gram-negative, Gram-positive, or anaerobic bacteria isolated from plaque or blood (P <.05). Bacteremia was present in all of the dogs studied, within 40 minutes from the initiation of the dental procedure, regardless of the severity of oral disease.
Conclusions — Gram-negative, Gram-positive, and anaerobic bacteria are present in blood during dental procedures; the bacteremia can persist beyond the dental procedure, and is not associated with the severity of dental disease.
Clinical Relevance — The nature and extent of bacteremia occuring during routine dental procedures is important in understanding a potential risk to dogs. 相似文献
90.
Andrea J. Fascetti Glenna E. Mauldin DVM MS G. Neal Mauldin 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1997,11(1):9-13
There are no available biochemical analyses that will reliably identify malnourished cats or enable monitoring them during supportive alimentation. Studies in people indicate that creatine kinase (CK) activity is high in malnourished patients and may decrease in response to nutritional intervention. The purpose of this study was to determine the value of quantifying serum CK activities in anorectic cats and to assess the usefulness of this test in monitoring nutritional support in these patients. Serum CK activity was evaluated in nonanorectic cats (Group 1, n = 25), and in hospitalized, anorectic cats that received nutritional support through a nasoesophageal tube (Group 2, n = 25). Anorectic cats had a significantly higher serum CK activity (median = 2,529 U/L, range 88 to 153,000 U/L) than the control group (median = 175 U/L, range 81 to 363 U/L, P < .001). There were significant positive correlations between serum CK and both aspartate transaminase (AST) ( P < .05; r = .59) and lactate dehydrogenase (LDH) (P < .05; r = .41) activities. Serum CK activity was significantly lower in anorectic cats after 48 hours of nutritional support than at time 0 ( P < .001) and eventually returned to normal with continued support. Serum CK activity may serve as a useful marker in assessing and monitoring nutritional status in cats. 相似文献