Electroencephalographic features in patients undergoing extracorporeal membrane oxygenation

Area of Science:

• Neurology
• Critical Care Medicine
• Neurophysiology

Background:

• Neurologic injury is a leading cause of death in extracorporeal membrane oxygenation (ECMO) patients.
• Neurological examination is often unreliable in sedated ECMO patients, necessitating additional neuromonitoring.
• The utility of electroencephalogram (EEG) in adult ECMO patients requires further assessment.

Purpose of the Study:

• To evaluate the occurrence of electroencephalographic abnormalities in adult ECMO patients.
• To determine the association between EEG findings and 3-month neurologic outcomes.

Main Methods:

• Retrospective analysis of ECMO patients with concomitant EEG recordings (April 2009-December 2018).
• EEG background classified into mild/moderate encephalopathy, severe encephalopathy, burst-suppression (BS), and suppressed background.
• Analysis of EEG findings in relation to unfavorable neurological outcome (Glasgow Outcome Scale < 4) at 3 months.

Main Results:

• 139 patients were analyzed; 71% received veno-arterial (V-A) ECMO, and 71% experienced unfavorable outcomes.
• EEG abnormalities included severe encephalopathy (21%), BS (3%), suppressed background (14%), seizures (8%), periodic discharges (7%), and asymmetry (19%).
• Suppressed background (OR 10.08) and intracranial hemorrhage/ischemic stroke (OR 4.57) were independently associated with unfavorable outcomes.

Conclusions:

• EEG is valuable for identifying adult ECMO patients at high risk of poor neurologic outcomes.
• A suppressed EEG background is a significant independent predictor of unfavorable neurologic outcomes in ECMO patients.