Thrombocytopenia and laboratory evidence of disseminated intravascular coagulation after shunts for ascites in malignant disease.

Twenty-eight peritoneovenous shunts were placed to relieve ascites in 26 patients with a variety of underlying malignancies. Nine of the patients had documented liver metastases and hyperbilirubinemia. Severe thrombocytopenia with laboratory evidence of disseminated intravascular coagulation (DIC) occurred in four of these nine patients following shunt placement. Relative or absolute thrombocytopenia was also commonly observed in this series. Other complications included pulmonary edema, ventricular tachycardia, culture-negative fever, pneumonia, and late shunt occlusion. Good palliation, with relief of abdominal pain or respiratory compromise, was achieved in 57% of these patients. Our experience suggests that DIC following peritoneovenous shunts in patients with malignancy may be more common than previously reported, although not as frequent as the incidence of DIC associated with shunt placement for cirrhotic ascites. Platelet aggregation or Factor X activation by ascitic fluid and failure of the liver to inactivate activated clotting factors may play a role in this coagulopathy. Because of the risk of potentially fatal DIC, palliative peritoneovenous shunts should be considered with caution in patients with liver metastases and hyperbilirubinemia.