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Anticoagulation-free VV ECMO for Acute Respiratory Failure

Anticoagulation-free VV ECMO for Acute Respiratory Failure: A Pilot Safety and Feasibility Randomized Clinical Trial

Status
Recruiting
Phases
Phase 2Phase 3
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT04273607
Acronym
A-FREE ECMO
Enrollment
40
Registered
2020-02-18
Start date
2022-09-01
Completion date
2027-01-30
Last updated
2026-01-16

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Extracorporeal Membrane Oxygenation Complication

Keywords

Extracorporeal membrane oxygenation, Anticoagulation, Thrombosis, Hemorrhage

Brief summary

Currently international experts recommend therapeutic anticoagulation for veno-venous extracorporeal membrane oxygenation (VV-ECMO). Reports and case series suggest that the absence of therapeutic anticoagulation is safe for VV-ECMO. No randomized control trials have assessed this. The aim of this pilot study is to assess safety and feasibility of an "anticoagulation-free strategy" for veno-venous ECMO (VV-ECMO) in Acute respiratory distress syndrome (ARDS).

Detailed description

Although anticoagulation targets and monitoring strategies vary around the world, the current practice is still to anticoagulate patients on ECMO, mostly with UFH. However, the use of heparin coated circuits has changed their thrombogenicity. Preliminary data suggest that a low-dose unfractionated heparin (UFH) strategy is non-inferior to a therapeutic dose UFH. Indeed, in daily practice, when a patient on ECMO has severe bleeding complications, UFH is often stopped until the hemorrhagic issue is under control, sometimes for days. This has led some to hypothesize that anticoagulation might not be necessary for VV-ECMO, and a few case series report little to no increase in adverse events as a result. There are currently no randomized controlled trials comparing anticoagulation to no anticoagulation for patients supported with ECMO. Anticoagulation is, for physiological reasons, less necessary during VV-ECMO than VA-ECMO and this is the reason why our pilot study will focus on VV-ECMO only. Whereas the whole ECMO device is identical for both configurations, the risk of systemic embolization (e.g., stroke) and its severe complications is much higher in VA-ECMO where blood is reinjected directly into the systemic arterial system. Moreover, in the presence of severely decreased left ventricular function requiring VA-ECMO, the risk of left ventricular thrombus is very high and requires anticoagulation. During VV-ECMO, the risk of systemic embolization is low because the whole circuit is on the right side of the heart and relatively preserved biventricular function is needed to perform VV-ECMO The hypothesis is that VV-ECMO is safe and feasible without therapeutic anticoagulation for adults with ARDS. The objectives of this study is to assess, through a pilot study, the safety and feasibility of an "anticoagulation free strategy" for veno-venous ECMO (VV-ECMO) in acute respiratory failure

Interventions

The intervention group will receive prophylactic heparin instead of standard of care therapeutic intravenous heparin

Sponsors

Damian Ratano
Lead SponsorOTHER
The Physicians' Services Incorporated Foundation
CollaboratorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE

Eligibility

Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No

Inclusion criteria

* Adult patient with ARDS on VV-ECMO

Exclusion criteria

* Contraindication to anticoagulation with UFH (known heparin-induced thrombocytopenia, active hemorrhage, any surgery precluding the use of anticoagulation), * Indication for therapeutic anticoagulation (pulmonary embolism or deep vein thrombosis, chronic anticoagulation therapy before ECMO insertion) * Low-flow (\<2 liters/min) VV-ECMO (ECCO2R)

Design outcomes

Primary

MeasureTime frameDescription
ECMO associated thrombotic complicationsthrough ECMO completion, an average of 14 daysComposite outcome of: * ECMO membrane oxygenator function assessed by trans-membrane pressure drop (\> 10mmHg/l/min) and a membrane PaO2/FiO2 ratio (\< 200mmHg) * Need to change ECMO circuit due to clotting or dysfunction * Platelets drop \>50% in 24 hours and \<50 /mm3 * Development of a clinically significant thromboembolic event * Clinical deep vein thrombosis, clinically suspected and confirmed by ultrasound * Acute ischemic stroke, clinically suspected and confirmed by head-CT

Secondary

MeasureTime frameDescription
Hemorrhagic complicationsthrough ECMO completion, an average of 14 daysHemorrhagic complications assessed and adapted as per Bleeding Academic Research Consortium (BARC) * Type 0: No bleeding * Type 1: Bleeding requiring transfusion of packed red blood cells (PRBC) or reduction of UFH * Type 2: Bleeding requiring transfusion of PRBC and reduction of UFH * Type 3: Life-threatening bleeding requiring, transfusion of PRBC, surgical intervention or discontinuation of ECMO * Type 4: Any fatal bleeding

Countries

Canada

Contacts

CONTACTDamian Ratano, MD
damian.ratano@chuv.ch+1 416-340-3601
CONTACTEddy Fan, MD, PhD
eddy.fan@uhn.ca+1 416-340-3601
PRINCIPAL_INVESTIGATORDamian Ratano, MD

University Health Network, Toronto

PRINCIPAL_INVESTIGATOREddy Fan, MD, PhD

University Health Network, Toronto

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026