The Role of ECMO Cannulation on Pediatric Mortality

Purpose:

Pediatric oncology, hemophagocytic histiocytosis (HLH), and bone marrow transplant (BMT) patients have variable degrees of underlying immune system suppression and/or dysregulation, putting them at high risk of developing serious illness and potentially requiring extracorporeal life support. Once supported by extracorporeal membrane oxygenation (ECMO), these patients are thought to have a higher mortality when compared to pediatric patients without these conditions. This study aims to describe specific approaches to ECMO support in this population, describing how these patients are cannulated, and how cannulae configuration potentially relates to outcomes.

Methods:

Retrospective data was collected from multiple institutions, identifying 176 pediatric patients with an oncologic, HLH, and/or BMT diagnosis who were supported by ECMO from 2010. This study evaluates pre-, on and post- ECMO characteristics including oncologic, HLH, and BMT diagnosis, status (active vs remission), reasons for ECMO, the type of ECMO, complications associated with ECMO support, and mortality.

Results:

Patients supported with veno-venous (VV) ECMO had the highest ECMO, ICU, and hospital survival compared to those supported with, or converted to, veno-arterial (VA) ECMO. Specifically, 67% of VV ECMO patients survived, while 53% of VA neck and 48% of VA femoral ECMO patients survived. Bleeding complications were high in all patients supported with ECMO. Intracranial hemorrhages occurred more frequently in patients with VA neck cannulation compared to femoral approaches, but even in patients on VV support without carotid cannulation, intra-cranial hemorrhage rates were high. Specifically, 27% of VA neck cannulated patients experienced a head bleed during ECMO, while 7% of VA femoral patients and 8% of VV ECMO patients did. Furthermore, 26% of VV ECMO patients required anticoagulation administration 48 hours prior to ECMO, while 94% of patients required anticoagulation during ECMO. 14% of VA neck cannulated patients and 10% of VA femoral cannulated patients required anticoagulation 48 hours prior to ECMO. However, 94% of VA neck cannulated patients and 86% of VA femoral cannulated patients required anticoagulation administration during ECMO. Lastly, femoral cannulation approaches resulted in limb ischemia with increased frequency.

Conclusions:

Pediatric patients requiring ECMO support during oncological processes require a variety of different cannulation strategies, each with their own associated risks. Overall patient morbidity including major bleeding events and ECMO complication rates are higher than can be expected compared to the average pediatric cohort.