Does a patient with polycythemia require medical clearance before surgery?

From the Guidelines

Patients with polycythemia require medical clearance before surgery to minimize the risk of perioperative complications, particularly thrombosis and bleeding, by optimizing hematocrit levels and addressing associated risks. The primary recommendation is to have the patient evaluated by a hematologist before proceeding with any elective surgery, as suggested by the NCCN guidelines 1. The hematologist should:

• Assess the severity and control of the polycythemia
• Optimize the patient's hematocrit levels, aiming for normalization or near-normalization of CBC, and maintain hematocrit <45% prior to performing elective surgery 1
• Consider phlebotomy if hematocrit levels are above target 1
• Evaluate and manage any associated thrombotic risk factors Specific pre-operative management may include:

• Phlebotomy to reduce blood viscosity
• Hydration to maintain adequate blood volume
• Anticoagulation management (if the patient is on anticoagulants), which should be withheld prior to surgery and restarted after surgery when considered acceptable depending on the bleeding risk 1
• Aspirin therapy assessment (often used in polycythemia patients), which should be discontinued one week prior to surgical procedure and restarted 24 hours after surgery or when considered acceptable depending on the bleeding risk 1 Justification: Polycythemia increases the risk of perioperative complications, particularly thrombosis and bleeding, due to increased blood viscosity, which can impair tissue perfusion and oxygenation 1. By optimizing hematocrit levels and addressing associated risks, the surgical team can minimize these potential complications and ensure safer anesthesia administration. Additional considerations:
• Inform the anesthesiologist about the patient's condition for appropriate intraoperative management
• Plan for potential need of blood products during surgery
• Consider postponing elective procedures if polycythemia is poorly controlled By obtaining proper clearance and management, the surgical team can significantly reduce the risks associated with operating on a patient with polycythemia.

From the Research

Medical Clearance for Surgery in Patients with Polycythemia

• Patients with polycythemia may require medical clearance before surgery due to the increased risk of bleeding and thrombosis 2, 3, 4, 5.
• The need for reduction of the packed cell volume in polycythaemic patients before operation is emphasized, and a full regimen of perioperative antithrombosis therapy is recommended 2.
• A systematic review of the literature suggests that interventions such as preoperative intermittent phlebotomy, generous perioperative fluid management, and postoperative therapy involving one antiplatelet agent and one anticoagulant may be considered to minimize complications in patients with polycythaemia vera undergoing cardiac surgery 3.
• Studies have shown that patients with polycythemia vera are at increased risk for transfusion intraoperatively and during hospitalization, and may require careful management to reduce the risk of thromboembolic complications 4, 5.

Preoperative Management

• Preoperative management may include reduction of the packed cell volume through phlebotomy, and administration of antithrombotic therapy such as heparin or dextran 2, 3.
• The use of antiplatelet agents and anticoagulants may also be considered, depending on the individual patient's risk factors and medical history 3, 5.
• Maintenance of a hematocrit <45% with aggressive phlebotomy is recommended in patients with polycythemia vera 6.

Risk Assessment

• Patients with polycythemia vera and essential thrombocythemia are at high risk for thrombotic and hemorrhagic events, and require careful risk assessment and management 5, 6.
• A prognostic risk model for patients with high-risk polycythemia vera and essential thrombocythemia has been proposed, taking into account factors such as age, prior thrombotic history, and cardiovascular risk factors 6.