Medical Care
Correction of the underlying cause of secondary polycythemia is the most important element of managment. This may include cessation of exogenous erythropoietin, repair of shunts or removal of tumors that are secreting erythropoietin.
The development of secondary erythrocytosis in response to tissue hypoxia is physiologic and probably beneficial to many patients. The expanded red blood cell mass may partially or totally compensate for the lack of oxygen delivery and result in tissue oxygenation to its normal level.
At hematocrit levels higher than 60-65%, however, the compensatory increase in red blood cells reaches the limit of benefit and begins to compromise circulation because of hyperviscosity. The latter leads to greater tissue hypoxia and erythropoietin secretion, a continued increase in red blood cells, and further impairment of circulation.
To restore viscosity and maintain circulation at its optimal level, phlebotomize or remove the offending red blood cells. Some patients with extreme secondary polycythemia have impaired alertness, dizziness, headaches, and compromised exercise tolerance. They may also be at increased risk for thrombosis, strokes, myocardial infarction, and deep venous thrombosis. These are the patients who require phlebotomy.
The optimal level of hematocrit is one that is as close as possible to normal without impairing the compensatory benefit of increased oxygen delivery. This may be determined individually by symptom relief or decompensation, depending on the viscosity level.
Repeated phlebotomies result in iron deficiency that can cause other symptoms. [25] This may limit or retard further erythropoiesis so that additional phlebotomies may not be necessary. Proper treatment of the underlying condition in polycythemia, when possible, is important, such as the following:
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Provide oxygen supplementation to patients with chronic obstructive pulmonary disease.
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Recommend weight loss in patients with obesity and hypoventilation.
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Recommend smoking cessation for patients with carboxyhemoglobin.
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Surgically correct arteriovenous shunts.
Surgical Care
Some cases of secondary polycythemia are caused by conditions that can be ameliorated by surgical removal or correction.
