American Society of Hirudotherapy

Challenges in the Monitoring of Therapeutic Plasma Exchange during Acute Heparin-Induced Thrombocytopenia in Adults under ECMO

Research article published in TH open : companion journal to thrombosis and haemostasis (2024)

Last Updated: June 18, 2026Reviewed by: ASH Editorial Board
Research article — evidence reviewArticle reference
Evidence: Case reportClinical TrialsGendron et al. · TH open : companion journal to thrombosis and haemostasis, 2024

Abstract

Therapeutic plasma exchange (TPE) has been proposed to remove heparin-induced thrombocytopenia (HIT) antibodies before planned thoracic surgery in patients with acute HIT and to allow brief re-exposure to heparin during surgery. In patients on extracorporeal membrane oxygenation (ECMO), simultaneous administration of TPE and alternative nonheparin anticoagulant therapies is challenging. We report 2 patients on ECMO with acute HIT who underwent repeated TPE to enable cardiothoracic surgery with the use of heparin. In both cases, serial monitoring of HIT antibody titer and heparin-induced platelet activation assay (HIPA) was performed. The effect of adding exogenous platelet factor 4 (PF4) in the HIPA was also tested. Negative anti-PF4/H IgG levels were achieved after 5 and 3 TPE sessions, respectively and patients could beneficiate from surgery with brief heparin re-exposure without any thrombotic complication. Negative HIPA results were obtained before negative anti-PF4/H IgG in one patient but remained positive in the other despite very low antibody titers. The addition of PF4 in HIPA led to more contrasted results for the two patients. Serial HIT screening including immunological and functional assays is necessary to closely monitor TPE in acute HIT patients on ECMO who require surgery. The addition of PF4 in HIPA could help detect clinically relevant platelet-activating antibodies and guide re-exposure to heparin.

Abstract sourced from PubMed (NCBI) for the cited record. See the original publication for the authoritative version.

Publication typeCase ReportsJournal Article

Summary

Peer-reviewed clinical and outcomes research relevant to anticoagulation, leech therapy, and microsurgical flap management. Indexed in PubMed and verified against the NCBI record.

Why This Matters for Hirudotherapy

This two-patient case series reports using repeated therapeutic plasma exchange (TPE) to clear heparin/PF4 antibodies in adults on ECMO with acute heparin-induced thrombocytopenia so that brief heparin re-exposure for cardiothoracic surgery could proceed; per the abstract both patients reached negative anti-PF4/heparin IgG after several TPE sessions and underwent surgery without thrombotic complications, with serial immunological and functional (HIPA) monitoring, including added exogenous PF4, recommended to guide re-exposure. Relevance to hirudotherapy is contextual: it illustrates how hard heparin is to manage once HIT antibodies appear, the scenario in which non-heparin direct thrombin inhibitors like hirudin are otherwise considered. Caveat: with only two patients and no comparison group this is preliminary, descriptive evidence, and it concerns heparin and TPE rather than any leech-derived agent.

Citation

Challenges in the Monitoring of Therapeutic Plasma Exchange during Acute Heparin-Induced Thrombocytopenia in Adults under ECMO.

Gendron et al. · TH open : companion journal to thrombosis and haemostasis, 2024

Added to ASH library: May 28, 2026 · Site last updated: June 18, 2026

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