Page 634 - Small Animal Internal Medicine, 6th Edition

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.)