What are the parameters for therapeutic phlebotomy?

Therapeutic Phlebotomy Parameters

Volume and Frequency

For hereditary hemochromatosis and iron overload, perform weekly or biweekly phlebotomy removing 500 mL of blood per session until serum ferritin reaches 50-100 μg/L, then transition to maintenance therapy. 1

Initial Treatment Phase

• Remove 500 mL of blood (one unit) per session during the initial iron depletion phase 1, 2
• Perform phlebotomy weekly or twice weekly as tolerated by the patient 1
• Each 500 mL unit removes approximately 200-250 mg of iron 1, 2
• Treatment duration may extend 2-3 years for patients with total body iron stores exceeding 30 g 1

Pre-Procedure Monitoring

• Check hemoglobin or hematocrit before every phlebotomy session 1, 3, 2
• Do not allow hematocrit/hemoglobin to fall more than 20% from baseline 1
• If hemoglobin drops below 12 g/dL, reduce phlebotomy frequency 3
• If hemoglobin drops below 11 g/dL, temporarily pause treatment 3

Ferritin Monitoring Schedule

• Check serum ferritin after every 10-12 phlebotomies (approximately every 3 months) during initial treatment 1, 4
• Once ferritin approaches 200 μg/L, increase monitoring frequency to every 1-2 treatment sessions 3
• Target ferritin level is 50-100 μg/L for both initial treatment completion and maintenance 1

Maintenance Phase

After reaching target ferritin of 50-100 μg/L, continue maintenance phlebotomy at individualized intervals to prevent iron reaccumulation. 1

• Maintenance frequency varies widely: some patients require monthly phlebotomy, others need only 1-2 units removed per year 1
• Not all patients reaccumulate iron and may not require maintenance therapy 1
• Continue checking hemoglobin before each session 3
• Monitor ferritin and transferrin saturation every 6 months during maintenance 3

Disease-Specific Parameters

Polycythemia Vera

• Maintain hematocrit strictly below 45% for all patients 2
• Consider lower target of approximately 42% for women and African Americans 2
• Remove one unit (500 mL) per session with appropriate fluid replacement 2
• Monitor for disease progression every 3-6 months 2

Congenital Heart Disease with Cyanosis

• Phlebotomy indicated only when hemoglobin >20 g/dL AND hematocrit >65% 2
• Perform only when hyperviscosity symptoms present (headache, fatigue) 2

Secondary Polycythemia

• Consider phlebotomy when hematocrit exceeds 52-55% 2

Critical Safety Considerations

Avoid Iron Deficiency

• Stop phlebotomy when ferritin reaches 50-100 μg/L to prevent overt iron deficiency 1
• Iron deficiency from excessive phlebotomy increases stroke risk and causes microcytosis 2

Patients with Advanced Disease

• Use extreme caution in patients with cardiac arrhythmias or cardiomyopathy due to increased risk of sudden death with rapid iron mobilization 1
• More cautious approach needed in elderly patients and those with cardiovascular disease 2

Dietary Restrictions

• Avoid vitamin C supplements as they accelerate iron mobilization to potentially dangerous levels 1, 3
• Avoid iron supplements 1, 3
• Patients with hemochromatosis should avoid raw shellfish due to Vibrio vulnificus risk 1, 4
• No other dietary adjustments necessary, as dietary iron restriction provides minimal benefit (2-4 mg/day) compared to phlebotomy (250 mg/week) 1

Alternative Approaches

Erythrocytapheresis

• Can remove up to 1000 mL of red blood cells per session (versus 250 mL with standard phlebotomy) 5
• Reduces total treatment duration by approximately 70% 5
• Consider for patients who poorly tolerate standard phlebotomy 3, 5
• Automated double red-cell phlebotomy removes 360-420 mL of RBCs and lowers hematocrit by 6.9% versus 3.0% with whole blood phlebotomy 6

Iron Chelation

• Reserve as second-line therapy only when phlebotomy is not feasible 3
• Deferoxamine: 20-40 mg/kg/day for secondary iron overload due to dyserythropoiesis 1
• Associated with gastrointestinal issues, kidney impairment, and neurotoxicity 1, 3