Accumulations of von Willebrand factor within ECMO oxygenators: Potential indicator of coagulation abnormalities in critically ill patients?

Abstract

Clot formation within membrane oxygenators (MOs) remains a critical problem during extracorporeal membrane oxygenation (ECMO). The composition of the clots-in particular, the presence of von Willebrand factor (vWF)-may be an indicator for prevalent nonphysiological flow conditions, foreign body reactions, or coagulation abnormalities in critically ill patients. Mats of interwoven gas exchange fibers from randomly collected MOs (PLS, Maquet, Rastatt, Germany) of 21 patients were stained with antibodies (anti-vWF and anti-P-selectin) and counterstained with 4',6-diamidino-2-phenylindole. The extent of vWF-loading was correlated with patient and technical data. While 12 MOs showed low vWF-loadings, 9 MOs showed high vWF-loading with highest accumulations close to crossing points of adjacent gas fibers. The presence and the extent of vWF-fibers/"cobwebs," leukocytes, platelet-leukocyte aggregates (PLAs), and P-selectin-positive platelet aggregates were independent of the extent of vWF-loading. However, the highly loaded MOs were obtained from patients with a significantly elevated SOFA score, severe thrombocytopenia, and persistent liver dysfunction. The coagulation abnormalities of these critically ill patients may cause an accumulation of the highly thrombogenic and elongated high-molecular-weight vWF multimers in the plasma which will be trapped in the MOs during the ECMO therapy.

• Authors: Tamara Steiger, Maik Foltan, Alois Philipp, Thomas Mueller, Michael Gruber, Andre Bredthauer, Lars Krenkel, Clemens Birkenmaier, Karla Lehle
• Journal: Artificial organs (Artif Organs) Vol. 43 Issue 11 Pg. 1065-1076 (Nov 2019) ISSN: 1525-1594 [Electronic] United States
• PMID: 31192471 (Publication Type: Journal Article)
• Copyright: © 2019 The Authors. Artificial Organs published by Wiley Periodicals, Inc. on behalf of International Center for Artificial Organ and Transplantation (ICAOT).

Chemical References

• von Willebrand Factor

Topics

• Adult
• Aged
• Blood Coagulation
• Critical Illness (therapy)
• Equipment Design
• Extracorporeal Membrane Oxygenation (adverse effects, instrumentation)
• Female
• Humans
• Male
• Middle Aged
• Oxygenators, Membrane (adverse effects)
• Platelet Activation
• Thrombosis (etiology)
• von Willebrand Factor (analysis)