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606    PART IV   Hepatobiliary and Exocrine Pancreatic Disorders


            the patient’s life as an alternative to surgery. This is usually   evidence that the liver progressively atrophies throughout
            because the client cannot afford referral, is unhappy about   life. Ultimately, more studies are needed to identify the fac-
  VetBooks.ir  the risks associated with surgery, or because the patient has   tors that are most important in determining prognosis after
                                                                 medical and/or surgical management and to help preopera-
            multiple or intrahepatic shunts. Mildly affected and older
            animals are good candidates for medical management, but
                                                                 poor outcome after surgery. The specific details of medical
            generally  these  are  dogs  with  smaller  shunting  fractions.   tively identify the small number of animals that will have a
            Dogs (particularly terriers) that present at an older age with   management of hepatic encephalopathy are given below.
            urate stones but no neurologic signs are also good candidates
            for medical management alone. In addition, dogs with con-  Management of Hepatic Encephalopathy
            current portal vein hypoplasia and/or MVD tend to have a   Whether caused by congenital or acquired PSS, the treat-
            higher surgical risk and are best managed medically. Medical   ment of HE in dogs is similar (Fig. 36.13). The main dif-
            management does not reverse the underlying disorder but   ference is that acquired PSSs are usually the result of portal
            can result in good long-term results. A recent prospective   hypertension, so treatment of its other manifestations and
            study of 126 dogs with congenital PSSs comparing surgical   the underlying liver disease will also be necessary in these
            with medical management found that surgically managed   cases (see earlier). Controlled trials have not been conducted
            dogs had a higher probability of survival over the course of   in animals to determine the optimal treatment for HE and
            the study (Greenhalgh et al., 2010). However, only 18 dogs   for each stage (mild, moderate, severe) of HE. Therefore
            had died by the end of the study, and survival time was   current recommendations are based on human studies and
            long for the dogs remaining alive in both groups (mean, 729   on anecdotal reports in dogs.
            days). Age at the time of surgery did not appear to affect   The goal of treatment in dogs with HE is to restore
            prognosis. Once the dog has reached adulthood, there is no   normal neurologic function by decreasing the formation





















                         A                                     B
















                                            C

                          FIG 36.13
                          Female German Shepherd Dog with noncirrhotic portal hypertension. (A) At 14 months of
                          age, with ascites and in poor body condition, but remarkably alert. (B) 5 years later on
                          medical management only—very stable and in good body condition, with no detectable
                          ascites. The dog lived for 8 years with a good quality of life before developing a
                          gastroduodenal ulcer (see Fig. 36-5). (C) Drugs that the dog received long term, in
                          addition to dietary management. (B and C reproduced by permission from Watson PJ:
                          Treatment of liver disease in dogs and cats. Part 2: Treatment of specific canine and feline
                          liver diseases, UK Vet 9:39, 2004.)
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