PB1360 - Plasmapheresis before lung transplantation is associated with an increase in tissue factor activity and procoagulant phospholipids

Background: Plasma exchange (PE) can be performed prior to organ transplantation in order to reduce anti-HLA antibodies. It is usually associated with a depletion in fibrinogen, coagulation factors and platelets.

Aims: To assess the impact of PE on hemostasis using innovative biomarkers [Tissue factor activity (TFA) and procoagulant phospholipids (PPL)]. Our objective is to analyze whether a procoagulant state can compensate the depletion of coagulation factors in lung transplantation (LT).

Methods: 49 lung transplanted patients were enrolled, PE with fresh frozen plasma (FFP) was performed in 23 (47%) cases prior to transplantation (Table 1). Blood samples were collected at various time (pre-, post-transplantation, day 1 and day 2). A commercially available chromogenic assay was used to quantify Tissue Factor-dependent Factor Xa generation, containing an anti-TF antibody for assay specificity. A commercially available assay was used to determine PPL.

Results: TFA was significantly increased preoperatively in patients with PE (11.5 [3.5-15.5] vs 3.4 [2.5-9.1] fM) as well as PPL (39.4 [34.6-42.2] vs 54.1 [38.7-61.4] sec) (Figure 1). Fibrinogen was slightly lower in patients with PE than those without PE (3.39 [2.84-3.93] vs 3.86 [3.52-4.94] g/L, p=0.013) whereas platelet counts were similar in both groups. Immediately after transplantation, in all patients, TFA was significantly higher than preoperatively (21 [13-38] vs 6 [3-14] fM) without difference between PE and non-PE group. Number of patients who received more than 3 blood products was similar in PE and non-PE patients (Fisher’s exact test, p=0.08 and p=0.76 for red blood cells and FFP, respectively). There was no difference in the occurrence of deep vein thrombosis within 15 days post-surgery between both group (p=0.51).

Conclusion(s): Preoperative plasmapheresis in LT is associated with an unusual procoagulant profile, but it is not associated with an elevated risk of thrombosis or a decrease need for blood products.