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111.
Urethral extension was performed in 14 cows with clinical urovagina and infertility. Urovagina was corrected in nine cows (64%) and was reduced in the others. Formation of fistulas at the cranial end of the extension site was the most frequent complication (4 cows). In one cow, the urethral extension was not extended far enough caudally. Eleven cows (79%) returned to fertility after surgery. Severity of urine pooling, cranial displacement of the urethral orifice, and severe preoperative vaginitis may explain the failure of the urethral extension in some cows.  相似文献   
112.
Two thousand sixty-three surgical procedures were performed on 1992 patients (1715 dogs and 277 cats). In a retrospective analysis, the procedures were categorized according to the expected degree of wound contamination, and corresponding wound infection rates were determined. The number of procedures in each category and the percent that became infected were as follows: clean (1100, 2.5%), clean-contaminated (554, 4.5%), contaminated (172, 5.8%), and dirty (237, 18.1%). The administration of antibiotics significantly reduced the frequency of wound infection in clean surgical procedures performed by senior veterinary students (p less than 0.05), but not in clean elective procedures performed by faculty or resident surgeons that required 90 minutes or less to complete. There was a significant correlation between elevation of rectal temperature postoperatively and increased duration of the surgical procedure. However, the rectal temperature measured the day after surgery was not an accurate predictor of wound infection.  相似文献   
113.
Sixty-eight cases of cortical bone sequestration in 67 equine patients were reviewed with regard to the clinical presentation, method of treatment, and outcome. All lesions were located in skeletal areas with minimal soft tissue coverage, with 53% of them in the metatarsal and metacarpal bones. At the time of admission, 60% of the patients with limb lesions were lame; the majority improved with therapy. After sequestrectomy, there was a trend for surgical wounds which could be managed by primary closure to heal more rapidly (3.8 weeks) than wounds which required second intention healing (6.4 weeks). The appearance of healed wounds, as evaluated by owners, was acceptable in 45 cases. Dissatisfaction with the appearance of the healed wounds in 22 cases suggested a need to address the issue of cosmetic results.  相似文献   
114.
Twenty-four dogs underwent unilateral excision of the femoral head and neck. An adjunctive biceps femoris muscle sling procedure was done in 16 dogs. In eight dogs (controls), the flap was dissected and returned to its original position. Four dogs with muscle slings were euthanatized on days 2, 5, 30, and 60, respectively. Four control dogs were euthanatized on day 2 and four dogs on day 5. Limb function did not differ consistently between dogs with muscle slings and control dogs. There was marked swelling and edema of the affected limb in half the dogs with muscle slings but not in the controls. Postoperative temperature elevations were significantly higher in dogs with muscle slings on days 1 and 2 (p less than 0.05). Infection was documented in four dogs with muscle slings. Flaps from control dogs had only minor gross and histologic abnormalities. On days 2 and 5, flaps from dogs with muscle slings appeared congested and swollen beneath and distal to the ostectomy site, with infarction involving 50 to 90% of the muscle mass. On days 30 and 60, the muscle slings were atrophic and fibrous, and by day 60 a synovial membrane covered the surfaces of all slings within the pseudarthrosis. Muscle fiber loss was attributed to infarction, necrosis, and disuse atrophy.  相似文献   
115.
The equine carpal joint was used to evaluate arthroscopic diagnosis of lesions created in joints obtained from horses euthanized for reasons other than lameness. Full-thickness articular defects were made in 13 sites within the antebrachiocarpal joint and middle carpal joint approximating those found in diseased carpal joints. Arthroscopic evaluation of the lesions included location, depth, and size of the defects. The joints were subsequently examined grossly. Results showed that, when compared to gross evaluation, arthroscopy is capable of accurately identifying subtle changes in articular cartilage and bone. A statistically significant increase in error rate was found for lesions at the medial aspect of the proximal radial carpal bone. Other sites with limited arthroscopic access were the proximal ulnar carpal bone, the proximal fourth carpal bone, and the distal intermediate carpal bone. The accuracy of arthroscopic identification of lesions improved significantly during the study as experience with the technique was gained.  相似文献   
116.
Gradual occlusion of the splenic vein, using a specialized device (ameroid constrictor), was evaluated experimentally in three normal beagle dogs. Splenoportograms were used to verify that total occlusion of the splenic vein had occurred in all dogs within 4 to 5 weeks after application of the device. The ameroid constrictor (AC) was also evaluated as a method of gradual vascular occlusion in 12 dogs and two cats with single, extrahepatic, portosystemic shunts (PSS). Serum bile acid (SBA) concentrations were measured and portal scintigraphy (PS) was performed on all 14 animals preoperatively and 10, 20, 30, and 60 days postoperatively. Two dogs (14%) died from portal hypertension in the early postoperative period. One dog and one cat developed multiple acquired PSS, confirmed by mesenteric portography 90 days after the operation. Portal scintigraphy confirmed total occlusion of the primary shunt in the other 10 animals. Shunt fractions (SF), as measured by PS on postoperative days 30 and 60, declined significantly from preoperative values. Significant decreases were noted between preoperative and postoperative values for preprandial SBA on postoperative day 60 and for postprandial SBA on postoperative day 30. SBA concentrations did not correlate with SF. Based on this study, gradual vascular occlusion using the AC is recommended as a method for treatment of single, extrahepatic, PSS.  相似文献   
117.
In humans, anesthetic uptake in a closed system with constant arterial concentration has been shown to be inversely proportional to the square root of time. A practical method for quantitative dosage of volatile anesthetic was derived from this. The method was evaluated in nine dogs anesthetized with a closed circle system using halothane and isoflurane. A unit dose (UD) of anesthetic was calculated in milliliters of vapor which was converted to milliliters of liquid and repeatedly administered into the expiratory limb between the squares of integer units of time (0-1, 1-4, 4-9 minutes, etc). The UD was derived as follows: UD = 2 f MAC X lambda B/G X 2 (kg)3/4, where f MAC was the desired alveolar concentration, lambda B/G the blood-gas partition coefficient, and 2 (kg)3/4 was an approximation of cardiac output. The method resulted in a stable plane of anesthesia and permitted continuous monitoring of O2 consumption. There was no significant difference between predicted and measured values of O2 consumption, cumulative doses, or alveolar concentrations at 9 and 16 minutes of anesthesia.  相似文献   
118.
Lateral Patellar Luxation in Miniature Horses   总被引:1,自引:0,他引:1  
Bilateral luxation of the patella in four Miniature Horses was corrected by a lateral release incision and medial imbrication of the parapatellar fascia to the tendon of the sartorius muscle. Before surgery, the four horses had a grade 3 to 4 lateral patellar luxation bilaterally and had difficulty walking. Trochlear ridge hypoplasia was evident on radiographs in each horse. Follow-up information varied from 11 months to 4 years after surgery. Three horses had no patellar luxation or lameness. The other horse had a normal right stifle, but patellar luxation (grade 3) had recurred on the left.  相似文献   
119.
An approach combining ventral midline celiotomy with transdiaphragmatic thoracotomy was evaluated in eight healthy cats for ligation of the thoracic duct system. Evans Blue solution was injected into the right colic lymph node to outline the intestinal lymphatic trunk and the thoracic duct system. Three cats (group 1) had mesenteric lymphangiograms and three (group 2) had only lymph node dye injection before thoracic duct ligation. The thoracic duct system was ligated with hemostatic clips just cranial to the aortic hiatus of the diaphragm, through a left transdiaphragmatic thoracotomy. Two cats (group 3) had prethoracotomy mesenteric lymphangiograms and thoracic duct isolation without ligation. Mesenteric lymphangiography was performed immediately after the surgery. In all of the cats, an absence of contrast medium in the thoracic duct system cranial to the surgical site was interpreted as complete obstruction. Four weeks after ligation, there was complete obstruction of the thoracic duct system with alternate lymphaticovenous communications in four of the six cats with ligated thoracic duct systems. Partial obstruction of the thoracic duct system with alternate lymphaticovenous communications was present in the other two cats. Both cats without thoracic duct ligation had patent thoracic duct systems. At necropsy of the six cats with ligated thoracic ducts, there was mild focal lymphadenitis of injected lymph nodes in three cats. The wall of the aorta adjacent to the hemostatic clips was normal in all six cats. The surgical technique was simple and provided excellent exposure. Vital staining with Evans Blue helped visualize the thoracic duct system, but mesenteric lymphangiography did not. Postligation lymphangiography was not of value in identifying incomplete ligation.  相似文献   
120.
Changes in synovial fluid and clinical variables after arthroscopic partial synovectomy of the middle carpal joint were studied in 12 normal horses. A 7 mm motorized synovial resector was inserted into each middle carpal joint; one middle carpal joint of each horse was randomly selected to have arthroscopic synovectomy (treated) and the opposite joint was lavaged (control). Lameness examinations and synovial fluid analyses were performed before operation and at 8, 14, 21, and 28 days after operation. Lameness variables did not differ between treated and control legs. Middle carpal and carpometacarpal joint circumference measurements were increased for 4 weeks. Synovial fluid specific gravity, pH, total protein, albumin concentration, and alpha-1-, beta- and gamma-globulin concentrations, at 8 and 14 days were significantly higher than before operation in both treated and control middle carpal joints. No significant differences were found between treated and control middle carpal joints at any time for color, clarity, pH, mucin clot formation, total protein, albumin, and globulin fractions. Arthroscopic partial synovectomy and lavage did not cause significant lameness and resulted in a synovitis indistinguishable from synovitis related to arthroscopic lavage alone.  相似文献   
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