Brain Magnetic Resonance Imaging Findings in Pediatric Patients Post Extracorporeal Membrane Oxygenation

Abstract

Neurologic complications can occur with extracorporeal membrane oxygenation (ECMO) due to several factors. Prior studies identified neonates as having unique risk factors and neuroimaging findings post ECMO. The aim of this study is to describe brain magnetic resonance imaging findings of pediatric patients treated with ECMO. We conducted a retrospective study of nonneonatal pediatric patients who underwent a comprehensive brain magnetic resonance imaging after ECMO between January 2000 and July 2015. We identified 47 pediatric patients in the study cohort with a median age of 8 months (interquartile range 3-170 months) and a median ECMO run duration of 7.15 days (interquartile range 3.8-10.3 days). Among indications for ECMO cannulation, 12 (25.5%) were cardiac, 23 (48.9%) were respiratory, and 12 (25.5%) were extracorporeal cardiopulmonary resuscitation cannulations. There were 33 (70.2%) veno-arterial cannulations of which 14 (42%) were transthoracic cannulations. There were 13 patients (27.7%) with an overall incidence of stroke: 8 patients had exclusive ischemic strokes, 2 had hemorrhagic strokes, and 3 had mixed types of stroke. The number of strokes in patients on veno-arterial ECMO was significantly decreased in patients undergoing transthoracic cannulation when compared with peripheral cannulation (7 vs. 42%, p = 0.05). Further study will be used to identify risk factors for neurological injury after ECMO and to look for outcome predictors based on neuroradiologic findings.

Stroke Patterns and Cannulation Strategy during Veno-Arterial Extracorporeal Membrane Support

“…A study of pediatric VA-ECMO patients by Werho et al 17 did not find association between stroke risk and cannulation site in neonates. Another study by Pinto et al 19 found that peripheral cannulation was associated with higher incidence of stroke in pediatric patients. Few studies have studied such associations among adult VA-ECMO patients.…”

Seizures Are Associated With Brain Injury in Infants Undergoing Extracorporeal Membrane Oxygenation

“…27 Specifically, pediatric patients with ischemic stroke, intraparenchymal hemorrhage, or venous thrombosis are at particularly high risk for seizures, ranging from 19% to 44%. 13 Patients on extracorporeal membrane oxygenation are also at high risk for these neurologic injuries, including, ischemic, hemorrhagic, or venous infarction, 4,28,29 with head ultrasonography identified as an insufficient screening tool for infarction. 28 Lin and colleagues 16 also showed 71% of patients with electrographic seizures in their extracorporeal membrane oxygenation cohort had acute imaging findings.…”

Neurologic Complications and Neuromonitoring on ECMO

“…Differential hypoxia, where the arterial oxygen tension is lower in the upper half of the body than in the lower half, is a phenomenon occasionally seen in patients supported on peripheral VA ECMO that causes cerebral ischemia [21]. For pediatric patients on VA ECMO, the incidence of stroke was much lower for transthoracic or central cannulation compared to peripheral cannulation [22]. VA ECMO is also unique in that poor cardiac function results in absence of pulsatile flow, with potential implications for cerebral autoregulation and vascular reactivity.…”

“…There are conflicting reports on laterality of lesions [37] but seem to occur in the middle cerebral artery vascular territory. A single center pediatric study found that majority of strokes were bilateral, a few were unilateral right sided lesions and no patients had unilateral left sided strokes; majority of the lesions were in the anterior cerebral circulation distribution [22]. Ischemic lesions are associated with electrographic seizures and decreased survival [38].…”