Neurologic Complications of Extracorporeal Membrane Oxygenation: A Review

Abstract

To review the evidence on neurologic complications in adult extracorporeal membrane oxygenation (ECMO) patients with regard to incidence, pathophysiology, risk factors, diagnosis, monitoring techniques, prevention, and management. Literature review. Observational studies and case reports from a variety of institutions. Adult ECMO patients. Six electronic databases were searched from their dates of inception to October 2016. The range of neurologic complications reported in adult ECMO patients included stroke, intracranial hemorrhage, and brain death. Due to a lack of standardized reporting, their true incidence may have been underestimated significantly. A variety of pathophysiologic mechanisms and risk factors have been proposed. Some of these are specific to venoarterial ECMO, whereas others may be more relevant to venovenous ECMO (eg, rapid correction of hypercarbia). With regard to diagnosis and monitoring, clinical examination alone can be challenging and insufficiently sensitive, particularly for the confirmation of brain death. Computed tomography is the main imaging modality for acute neurologic assessment because magnetic resonance imaging is not feasible in these patients. Options for neuromonitoring are limited, although cerebral near-infrared spectroscopy may be useful. There are very limited data to guide the management of specific complications such as intracranial hemorrhage, which remains a leading cause of mortality in ECMO patients. ECMO can be lifesaving and is being used increasingly for severe respiratory and/or cardiac failure. However, it remains associated with significant neurologic morbidity and mortality. Greater research clearly is needed to determine the best approach to the assessment and management of neurologic complications in this rapidly growing patient population.