D-dimers Are a Predictor of Clot Volume Inside Membrane Oxygenators During Extracorporeal Membrane Oxygenation

Abstract

Thrombosis inside the membrane oxygenator (MO) is a critical complication during venovenous extracorporeal membrane oxygenation (ECMO). The aim of this study was to prove if thrombotic clots manifest within the MO when D-dimer levels are elevated over a long-term period. Heparin-coated polymethylpentene MOs (n = 13) were exchanged due to high plasma D-dimer levels. Clot volume was calculated using multidetector computed tomography (MDCT). Coagulation parameters and MO function were analyzed before and after MO exchange. Before MO exchange, D-dimer levels increased significantly in each patient (11.5 [6.5-15.5] mg/L to 35.0 [34-35] mg/L, P ≤ 0.001). High levels of D-dimers were tolerated for 1 to 6 days. Additionally, fibrinogen concentration (n = 8) and platelet count decreased (n = 8). Within 48 h after exchange, D-dimer levels decreased significantly (n = 11, 12 [8-16] mg/L, P = 0.004). Fibrinogen concentration and platelet counts increased. Clots were found in all MOs in the inlet part of the device. Clot volume (16-106 cm(3) ) did not correlate with MO support time but increased significantly when high D-dimer levels were accepted for >2 days. An increase or high levels of D-dimers in absence of other explaining pathology during ECMO therapy reflected coagulation activity within the MO. Evidence of clots within the MO at high D-dimer levels and decrease after exchange underline the relevance of D-dimer testing during ECMO treatment. Besides, surveillance of MOs during ongoing ECMO therapy will help to predict clot formation, and to avoid system-induced coagulation disorders as well as critical situations.

Technical Indicators to Evaluate the Degree of Large Clot Formation Inside the Membrane Fiber Bundle of an Oxygenator in an In Vitro Setup

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Emergency Abdominal Surgery Outcomes of Critically Ill Patients on Extracorporeal Membrane Oxygenation: A Case‐Matched Study with a Propensity Score Analysis

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Initial Clinical Experiences With Novel Diagonal ECLS System in Pediatric Cardiac Patients

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