Outcomes after extrahepatic portosystemic shunt ligation in 49 dogs.
ABSTRACT To evaluate outcomes after attenuation of extrahepatic portosystemic shunts in dogs using surgical silk.
Case records were reviewed for degree of surgical attenuation, experience of the primary surgeon, perioperative mortality and problems related to persistent portosystemic shunting or shunt ligation. Presence of portosystemic shunting after surgery was evaluated by ammonia tolerance testing, measurement of postprandial serum bile acid, plasma urea and cholesterol concentrations and liver enzyme activity. The influence of age, postocclusion portal pressure, primary surgeon, degree of attenuation and postoperative biochemical findings on the occurrence of postoperative problems was assessed.
The mortality rate was 2.1%. Shunt attenuation was complete in 34% and partial in 66% of dogs. Portal hypertension necessitating ligature removal was encountered in only one dog. Five dogs experienced neurological abnormalities (seizures or ataxia), possibly as a manifestation of 'postligation seizure syndrome'. Postoperative liver function was normal in 78% of dogs, including 70% with partial shunt attenuation. Experience of the surgeon was related positively to outcome after partial attenuation (P = 0.002). Postoperative biochemical evidence of abnormal liver function was the most sensitive predictor of recurrence of clinical signs referable to persistent portosystemic shunting.
In the hands of an experienced surgeon, surgical attenuation of single extrahepatic shunts was safe and effective, even in animals with partial attenuation. Most dogs with biochemical evidence of persistent shunting suffer relapse of clinical signs within 18 months of surgery. Postligation neurological syndromes of variable intensity may be more common than previously thought.
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ABSTRACT: To determine if there were significant changes in prothrombin time (PT), partial thromboplastin time (PTT), and fibrinogen levels in dogs with naturally occurring congenital portosystemic shunts (CPSS) and to determine if there was any association between these values, serum albumin concentration, and the ability to attenuate the shunt vessel. Retrospective clinical study. Thirty-nine client-owned dogs. Medical records of 60 dogs with confirmed CPSS were retrospectively evaluated. Hemostatic profiles had been performed before surgery in 39 cases. Dogs with CPSS had significantly higher values for PTT (P < .001) when compared with normal dogs. Of the total number of dogs, 64.1% had a PTT greater than 16 seconds (25/39). PTT was prolonged by 25% or more in 51.3% of dogs (20/39). PT tended to be higher in dogs with CPSS (P = .036), although only 7.7% (3/39) of dogs had a PT greater than 12 seconds (the maximum reference value). Dogs with CPSS had significantly lower values for albumin and fibrinogen (P < .001). Platelet numbers were within the normal range in 87.2% of cases (34/39). Of the 5 dogs with platelet numbers outside the normal range, 3 were mildly thrombocytopenic. Fibrin degradation product concentrations were not elevated in any dogs tested (N = 22). There was no significant difference in any of the measured variables between dogs with extrahepatic shunts and those with intrahepatic shunts (P > .1). For PT, PTT, albumin, and fibrinogen, there was no significant difference between dogs that underwent total, partial, or no attenuation (P > .3). Dogs with CPSS have a tendency to have a prolonged PTT. There was no significant difference in hemostatic profile results between dogs with intrahepatic shunts versus extrahepatic shunts. Preoperative hemostatic profile abnormalities were not useful as predictors of ability to attenuate CPSS. Prolonged PTT was not associated with bleeding tendencies in any of the dogs. Assays of individual clotting factors may help to further characterize the abnormalities present in animals with CPSS and may identify specific factor deficiencies. This might enable identification of a noninvasive diagnostic or prognostic indicator.Veterinary Surgery 01/2001; 30(1):97-104. · 1.24 Impact Factor
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ABSTRACT: Dans sa forme la plus pure, la radiologie interventionnelle désigne l’utilisation de l’imagerie radiologique afin de guider le chirurgien dans la réalisation d’un nombre varié d’interventions mini-invasives, au travers de l’utilisation d’un équipement spécialisé. Les techniques de radiologie interventionnelle peuvent être plus efficaces, plus sûres, moins douloureuses et associées à un temps de convalescence plus court que pour les techniques de chirurgie conventionnelle. La première technique a été décrite en 1953 lors d’une procédure diagnostique. Dix ans plus tard, la première procédure interventionnelle était décrite. Depuis la radiologie interventionnelle a été utilisée dans un grand nombre de procédures. Certaines ont été transposées en médecine vétérinaire. Chaque année de nouvelles techniques sont développées, offrant au vétérinaire un large choix de techniques, notamment dans le domaine de la médecine cardio-vasculaire des carnivores domestiques.
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ABSTRACT: ABSTRACT: PERCUTANEOUSLY CONTROLLED HYDRAULIC OCCLUDERS AND THEIR APPLICATION IN GRADUAL VENOUS OCCLUSION By Colin Wayne Sereda December, 2004 Chair: Christopher A. Adin Major Department: Veterinary Medicine Surgical occlusion is widely accepted as the treatment of choice for congenital portosystemic shunts in dogs. Unfortunately, acute occlusion of portosystemic shunts is frequently associated with life threatening portal hypertension. Despite years of research in this area, veterinary surgeons continue to search for a safe and effective method to produce gradual occlusion of portosystemic shunts in dogs. The overall goal of this thesis project was to evaluate a novel technique for gradual venous occlusion using a percutaneously controlled silicone hydraulic occluder. ABSTRACT: In order to identify the qualities desired in an ideal surgical device for treatment of congenital portosystemic shunts, a comprehensive literature review pertaining to congenital portosystemic shunts in veterinary patients was performed. Following the literature review, a prospective evaluation of the silicone hydraulic occluder was performed using a rat model. The vena cava of each rat was instrumented with a silicone hydraulic occluder, as well as a perivascular ultrasonic flow probe. Gradual decrease in blood flow was documented during an 8-week period, although limitations were identified with the experimental model due to the size disparity between the large implants and the small, compressible rat vena cava. A second problem identified was a marked difference between the predicted filling volume of the occluder and the actual filling volume required to cause cessation of blood flow. ABSTRACT: It was hypothesized that several factors contributed to this phenomenon, including diffusion of filling solutions, size differences in the HOs secondary to manufacturing inconsistencies, and plastic deformation of the materials over time. Due to questions regarding the reliability of the vascular occluders in chronic applications, a series of in vitro experiments were performed to evaluate the mechanical properties of hydraulic occluders immersed in simulated body fluid. Data from these studies confirmed that air diffused rapidly from the occluders, whereas both saline and sodium hyaluronate functioned as appropriate filling solutions. Size differences among the occluders secondary to manufacturing were statistically significant, and could potentially affect filling volumes and fine adjustment of the level of occlusion in chronic applications. ABSTRACT: Changes in internal pressure were also noted to occur over time, suggesting that mechanical deformation of the silicone occluders may also contribute to changes in filling volume required. Mechanical deformation appeared to be more significant in the smaller occluders studied. Typescript. Text (Electronic thesis) in PDF format. System requirements: World Wide Web browser and PDF reader. Mode of access: World Wide Web. Title from title page of source document. Document formatted into pages; contains 69 pages. Thesis (M.S.)--University of Florida, 2004. Includes Vita. Includes bibliographical references.