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 uid administration beyond replacement may be associated with cardiopulmonary failure as these animals are completely volume expanded. In cases that require multiple phlebotomies in a short period, replacement of coagulation factors and albumin with plasma may need to be considered. The target hematocrit is higher in dogs than in cats, as well as in cases with cardiopulmonary disease, but generally is greater than 50%.
Longterm control of absolute polycythemia may
be achieved by periodic phlebotomies, radioactive phosphorus, and/or chemotherapy. Chemotherapy
with hydroxyurea at 10-25 mg/kg twice daily to once every other day is commonly used. Animals treated with chemotherapy need to be monitored, not only by PCV measurements as for phlebotomized patients, but also by complete blood cell counts to identify drug induced cytopenias. Hydroxurea has also caused nail sloughing. Furthermore, antithrombotic doses of aspirin (1 mg/kg per day) may be considered, but there is no proof that
it reduces the risk of thrombosis, and higher doses may lead to increased bleeding tendencies. Polycythemic animals may remain asymptomatic for weeks to years and, in some cases, can be successfully managed for years. Longterm follow up has not been reported in animals, although the author has observed persistent polycythemia for more than a decade in certain animals.
An Urban Experience

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