You hospitalize Olivia, place an intravenous catheter, and start crystalloid fluid therapy and intravenous ampicillin (20 mg/kg every eight hours). You also administer a lactulose enema, which can be repeated depending on her response to therapy. You run an in-house serum chemistry profile and Olivia’s blood glucose and albumin concentrations and other measurements are normal but her ALT activity has increased to 350 IU/L (it was 145 IU/L previously).
Alterations in portal blood flow and subsequent portal hypertension may sometimes result in gastrointestinal ulceration as evidenced by anemia, black tarry stools, or both. This may be treated with gastric protectants such as famotidine (0.5 to 1 mg/kg/day intravenously or orally) or omeprazole (0.5 to 1 mg/kg/day orally) and sucralfate (1 g/25 kg orally every eight hours).
Olivia shows improvement within the first 12 hours and is bright and alert by 24 hours after treatment. She has not exhibited any neurologic signs.
The owner is now considering surgical correction of the shunt, and you discuss the potential risks of surgery (e.g. postoperative seizures, gastrointestinal ulceration due to altered portal blood flow). If they do well in the perioperative period, dogs with extrahepatic shunts can have a good long-term outcome. About 30% to 60% of patients cannot tolerate complete acute occlusion of the shunt vessel, so devices such as ameroid constrictors and cellophane bands provide gradual, complete shunt occlusion with excellent outcomes. Interventional radiology allows placement of coils at the level of the shunt to partially occlude the vessel, but long-term outcome studies are lacking.
A recent study evaluated the use of levetiracetam at 20 mg/kg given orally every eight hours prior to surgical extrahepatic PSS correction with an ameroid constrictor.2 The drug was administered for a minimum of 24 hours before surgery and significantly decreased the risk of postoperative seizures and death.