Management of systemic unfractionated heparin anticoagulation during therapeutic plasma exchange

Background:: Therapeutic plasma exchange (TPE) may remove medications from the patient's plasma. Data is limited on the effect of TPE on unfractionated heparin (UFH). Study Design and Methods: A retrospective review was performed of patients receiving TPE and continuous IV infusion UFH from 1/1/2008 to 6/30/2010. TPE with plasma or 5% albumin for replacement fluid and pre and post anti-Xa levels within approximately six hours were analyzed. Results: Three patients had 15 TPE with plasma replacement. Anti-Xa levels decreased 47% (mean, −0.25 IU/mL) for two TPE when UFH was not changed, 78% (−0.35 IU/mL) for one TPE when the UFH rate was decreased 25%; and 61% (mean −0.72 IU/mL) for two single volume TPE and 87% (−0.65 IU/mL) for one 1.5 plasma volume TPE when UFH was stopped. During nine TPE, the UFH rate was increased by 65% resulting in a mean increase in the anti-Xa level (mean 0.06 IU/mL, 30%). One patient had five single plasma volume TPE with 5% albumin. Anti-Xa levels decreased when the UFH was not changed (−0.06 IU/mL, 38%) and increased when UFH was increased by 30% (0.19 IU/mL, 61%) and 69% (mean 0.04 IU/mL, 15% in three TPE). The PTT increased with all albumin procedures, with more marked increases observed when the UFH rate was increased, while the antithrombin level decreased (mean 65%). Conclusion: Heparin was removed from the patient's plasma during TPE. Adjustment of the dose during TPE may be necessary to maintain therapeutic drug levels. Methods for monitoring UFH therapy may not agree. J. Clin. Apheresis 31:507–515, 2016.