Polycythemia Evaluation and management Diagnostic criteria Confirm polycythemia by demonstrating a persistently elevated hematocrit on at least 2 measurements over a 3-month period. Identification of comorbidities Screen for hypertension, dyslipidemia, diabetes, and tobacco use. Thrombophilic workup Evidence is lacking to support routine thrombophilia screening in polycythemia vera. B Management of apparent erythrocytosis Advise a reduction or elimination of factors which may contribute to apparent erythrocytosis, such as a reduction in smoking and alcohol intake and control of hypertension (without the use of a thiazide diuretic). B Management of apparent erythrocytosis Q Does the patient have a recent history of thrombosis, or additional risk factors for thrombosis? Q Does the patient have a hematocrit > 0.54? Yes to any Consider venesection in patients with a recent history of thrombosis or additional risk factors for thrombosis, in patients whose hematocrit exceeds > 0.54. C No to all Monitor patients not treated with phlebotomy to exclude a further rise in hematocrit and possible evolution to absolute erythrocytosis. B Management of idiopathic erythrocytosis Q Does the patient have idiopathic erythrocytosis? Yes Initiate venesection to reduce the hematocrit to < 0.45 in patients with idiopathic erythrocytosis and a hematocrit > 0.54. B Initiate venesection to reduce the hematocrit to < 0.45 in patients with idiopathic erythrocytosis and a hematocrit < 0.54 in whom there is an risk of thrombosis, i.e. evidence of ischemia, previous history of thrombosis, peripheral vascular disease, diabetes or hypertension. B Avoid administering cytoreductive therapy in patients with idiopathic erythrocytosis. D No Management of high affinity hemoglobins Q Does the patient have symptoms and signs of polycythemia, such as dizziness, dyspnea, or angina? Q Has the patient had 1 thrombotic complications? Q Does the patient have a family member with a high oxygen affinity Hgb, similar Hgb concentration, and comparable risk factors for thrombosis, who has developed thrombotic complications? Yes to any Consider venesection for high affinity Hgbs in patients with symptoms of polycythemia, thrombosis, or a history of thrombosis in a family member affected by the disease with comparable thrombotic risk profile. Consider targeting a hematocrit < 0.60 in patients managed with venesection, rather than targeting a normal hematocrit. No to all Patients with pulmonary disease Q Does the patient have pulmonary disease? Yes Refer to a respirology specialist for consideration of long-term oxygen therapy and other thrapies. A Consider ACEIs or ARBs in patients who do not tolerate venesection, based on limited evidence. C No Patients with cyanotic heart disease Q Does the patient have cyanotic heart disease? Yes Manage patients with cyanotic congenital heart disease and an erythrocytosis in a specialized congenital heart disease unit. B Perform isovolumic venesection when the patient has symptoms of hyperviscosity; no general target Hct can be suggested and treatment should be individualized. B No Patients post renal transplantation Q Does the patient have a history of renal transplantation? Counsel patients to maintain adequate fluid intake in order to avoid dehydration. Initiate an ACEI or an ARB. Perform venesection to target a reduction in hematocrit of < 45%. B