What lab values are checked for plasma pheresis?

Laboratory Monitoring for Plasmapheresis

Before initiating plasmapheresis, you must check a complete coagulation profile including PT, INR, APTT, fibrinogen, platelet count, and a comprehensive metabolic panel with electrolytes and calcium. 1

Pre-Procedure Essential Laboratory Tests

Coagulation Parameters

• Prothrombin Time (PT) and INR: Essential to assess baseline coagulation status and risk of bleeding complications during the procedure 2
• Activated Partial Thromboplastin Time (APTT): Required to evaluate intrinsic coagulation pathway function 2
• Fibrinogen level: Must be maintained above 100-150 mg/dL during plasmapheresis to prevent hemorrhagic complications 3
• Platelet count: Critical baseline measurement, as counts should be maintained above 30-50 × 10⁹/L during the procedure 3

Hematologic Assessment

• Complete blood count with differential: Necessary to evaluate baseline hemoglobin, hematocrit, and white blood cell counts 1
• Peripheral blood smear: Should be examined for specific findings such as rouleaux formation or circulating abnormal cells 4

Biochemistry Panel

• Comprehensive metabolic panel: Including liver function tests, renal function tests (creatinine, BUN), and electrolytes 4
• Serum calcium and albumin: Essential as plasmapheresis can cause hypocalcemia due to citrate anticoagulation used during the procedure 4
• Serum protein electrophoresis: When plasmapheresis is indicated for paraproteinemia or hyperviscosity syndromes 5

Intra-Procedure Monitoring

Fluid and Electrolyte Balance

• Continuous electrolyte monitoring: Particularly calcium, as citrate anticoagulation chelates calcium and can cause symptomatic hypocalcemia 1
• Strict fluid balance tracking: Close medical and nursing supervision is necessary to monitor fluid balance and prevent volume-related complications 5

Hemodynamic Parameters

• Continuous vital signs monitoring: Blood pressure should be monitored closely, as hypotension occurs in 8.4% of procedures 1
• Cardiac rhythm monitoring: Arrhythmias develop in 3.5% of procedures and require immediate recognition 1

Post-Procedure Laboratory Assessment

Immediate Post-Procedure (Within 24 Hours)

• Repeat coagulation profile: PT, INR, APTT, fibrinogen, and platelet count to assess for coagulopathy 2
• Electrolytes and calcium: To identify and correct any imbalances induced by the procedure 1
• Complete blood count: To monitor for anemia or thrombocytopenia 1

Sample Stability Considerations

• PT and INR samples: Can be safely stored in refrigerator for up to 24 hours if immediate testing is not possible 2
• APTT samples: Deteriorate at 12 hours in refrigerator and should be processed immediately or frozen 2
• All coagulation samples: Should be frozen if storage beyond 24 hours is required, as they remain stable for up to 36 hours in freezer 2

Special Monitoring for Specific Conditions

Hyperviscosity Syndromes

• Serum protein electrophoresis and immunofixation: To quantify monoclonal protein levels before and after plasmapheresis 4
• Serum immunoglobulin quantitation by nephelometry: Complementary to electrophoresis for accurate protein measurement 4

Thrombotic Thrombocytopenic Purpura

• Lactate dehydrogenase (LDH): Marker of hemolysis and disease activity 1
• Peripheral smear for schistocytes: To assess for ongoing microangiopathic hemolysis 1

Critical Pitfalls to Avoid

• Do not delay plasmapheresis for minor coagulation abnormalities in life-threatening conditions, but correct severe coagulopathy (fibrinogen <100 mg/dL, platelets <30 × 10⁹/L) before elective procedures 3
• Do not use room temperature storage for coagulation samples, as PT, INR, and APTT all deteriorate within 12 hours at room temperature 2
• Do not assume stable coagulation parameters throughout multiple plasmapheresis sessions; repeat testing before each procedure is essential 1
• Avoid invasive procedures such as central line placement in patients with severe coagulopathy until parameters are corrected 3