How are fibrinogen levels affected by plasmapheresis (plasma exchange) for ABO incompatible (ABOI) kidney transplants?

From the Guidelines

Plasmapheresis significantly reduces fibrinogen levels during ABOI kidney transplant preparation, with a typical decrease of 60-70% from baseline after each session, as supported by the general understanding of plasmapheresis effects on plasma proteins 1. The reduction in fibrinogen levels is clinically significant because fibrinogen is essential for blood clotting, and levels below 100 mg/dL may increase bleeding risk during surgery.

• Fibrinogen levels should be monitored before and after each plasmapheresis session, with most centers targeting to maintain levels above 100-150 mg/dL.
• If levels drop too low, cryoprecipitate (typically 10 units) or fresh frozen plasma may be administered to replenish fibrinogen, with the goal of achieving a plasma fibrinogen level ≥ 1.5 g/L, as recommended for treatment of hypofibrinogenemia in major bleeding 1. The typical ABOI desensitization protocol includes 4-6 plasmapheresis sessions before transplantation, with each session removing approximately one plasma volume.
• Fibrinogen levels generally recover within 24-48 hours after plasmapheresis, but repeated sessions scheduled closely together (often every other day) can lead to cumulative depletion. This fibrinogen reduction occurs alongside the intended removal of anti-ABO antibodies, which is the primary goal of plasmapheresis in this setting. The use of fibrinogen concentrate or cryoprecipitate is recommended if major bleeding is accompanied by hypofibrinogenemia, with an initial supplementation of 3–4 g, as suggested by recent guidelines 1.

From the Research

Fibrinogen Levels and Plasmapheresis in ABOi Kidney Transplants

• Fibrinogen levels are affected by plasmapheresis in ABO-incompatible (ABOi) kidney transplants, with significant depletions observed after the procedure 2.
• The median fibrinogen depletions were ~60% (filtration therapeutic plasmapheresis), 64% (double-filtration plasmapheresis), and 76% (centrifugation therapeutic plasmapheresis) 2.
• These findings suggest that plasmapheresis can significantly reduce fibrinogen levels, which may be an important consideration in the management of ABOi kidney transplant patients.
• However, the clinical significance of these findings and their impact on patient outcomes are not fully understood and require further study.

Comparison of Plasmapheresis Modalities

• Different plasmapheresis modalities, such as centrifugation therapeutic plasmapheresis, filtration therapeutic plasmapheresis, and double-filtration plasmapheresis, may have varying effects on fibrinogen levels and isoagglutinin titers 2.
• The choice of plasmapheresis modality may depend on various factors, including the patient's specific needs and the transplant center's protocols.
• Further research is needed to compare the efficacy and safety of different plasmapheresis modalities in ABOi kidney transplant patients.

Clinical Outcomes and Fibrinogen Levels

• The relationship between fibrinogen levels and clinical outcomes in ABOi kidney transplant patients is not well established 3, 4, 5, 6.
• While plasmapheresis can reduce fibrinogen levels, its impact on patient survival, graft survival, and other clinical outcomes is not fully understood.
• Further studies are needed to investigate the clinical significance of fibrinogen levels in ABOi kidney transplant patients and to determine the optimal management strategies for these patients.