ECMO Hemostatic Transfusions in Children

Due to coagulopathy and thrombocytopenia induced by hemodilution and the extracorporeal circuit itself, children supported by extracorporeal membrane oxygenation (ECMO) are at significant risk of bleeding. In order to prevent bleeding, pediatric intensivists often prescribe prophylactic platelet transfusions. However, in observational studies, prophylactic platelet transfusions to children on ECMO have been independently associated with increased thrombosis, mortality, and paradoxically, increased bleeding. Guidelines to direct platelet transfusions in this patient population are limited by the lack of evidence and therefore based on expert opinion alone. Given the significant associated risks, it is crucial to provide evidence to guide clinicians.

The ECSTATIC pilot, a randomized controlled trial endorsed by BloodNet, PediECMO, the Extracorporeal Life Support Organization (ELSO), and the Pediatric Acute Lung Injury and Sepsis Investigators (PALISI), will be conducted in ten sites (9 in the US and 1 in Israel). The investigators will enroll an anticipated 50 consecutive critically ill children (0 to <18 years of age), admitted to a participating pediatric, neonatal, or cardiac intensive care unit (PICU/NICU/CICU), on ECMO, and who have either no bleeding or minimal bleeding.

Non-bleeding children 0 to less than 18 years of age will be randomized 1:1 to either a platelet transfusion threshold of 90 x10e9/L (higher platelet transfusion strategy) or 50 x10e9/L (lower platelet transfusion strategy). Participants will be followed until progression to severe bleeding and/or severe thrombosis, decannulation from ECMO, or reach 21 days.

In this pilot, the investigators will test the separation between the lower and higher transfusion strategies. The primary outcomes will be the separation between pre-transfusion platelet counts, and the total platelet dose (in mL/kg/run). Secondary outcomes will be feasibility of patient enrollment and ability for an adjudication committee to determine the severity of bleeding and thrombotic outcomes.

The purpose of this pilot study is to determine the feasibility of the transfusion strategies, intervention parameters, subject availability, and other information regarding outcomes that are essential to complete the design of a large randomized controlled trial.

The large future trial will evaluate the efficacy of the two transfusion strategies, in terms of progression to severe bleeding and/or severe thrombosis. To adequately calculate the sample size, the investigators need to know the difference between the pre-transfusion platelet counts, the screening and inclusion rates, the proportion of patients who are consented within the first 24 hours after cannulation, the proportion of transfusions that are compliant with each arm's strategy, and the number of temporary suspensions.

The proposed pilot trial is innovative in that it is focused on children supported by ECMO, a population in whom transfusion strategies have never been tested previously; it involves the largest separation between the two arms of any platelet transfusion trial conducted in the past; and it involves two newly developed definitions of bleeding and thrombosis particularly applicable to children supported by ECMO.

The pilot trial will provide necessary and sufficient information to proceed with the definitive ECSTATIC Randomized Controlled Trial (RCT) to evaluate the impact of a lower prophylactic platelet transfusion threshold on the clinical outcomes in children on ECMO. ECSTATIC has the potential to optimize efficacy, to reduce platelet transfusion exposure and to decrease mortality and morbidity of these extremely ill infants and children.

Inclusion criteria

• Critically ill children (0 to <18 years of age)
• Admitted to a participating pediatric, neonatal, or cardiac intensive care unite (PICU/NICU/CICU)
• On extracorporeal Membrane Oxygenation (ECMO)
• Who have either no bleeding or minimal bleeding, within 24 hours of cannulation. Minimal bleeding is defined as:

• streaks of blood in endotracheal tube or during suctioning only
• streaks of blood in nasogastric tube
• macroscopic hematuria
• subcutaneous bleeding (including hematoma and petechiae) < 5 cm in diameter
• quantifiable bleeding < 1mL/kg/hr (e.g., chest tube)
• bloody dressings required to be changed no more often than each 6hr, or weighing no more than 1mL/kg/hr if weighed, due to slow saturation

Exclusion criteria

• Post-conception age < 37 weeks at time of screening
• Underlying oncologic diagnosis (defined as receipt of chemotherapy or radiation in the last six months) or recipient of bone marrow transplant in the last year
• Congenital bleeding disorder
• Pregnant or admitted post-partum
• Decision to withdraw or withhold some critical care or interventions
• Known objection to blood transfusions
• On ECMO for > 24 hours at time of enrollment