We hypothesized that patients undergoing extracorporeal membrane oxygenation (ECMO) would have electrographic seizures at a similar frequency as other intensive care unit (ICU) populations and that interictal patterns observed during continuous electroencephalography (cEEG) may be predictive of adverse neurological events and discharge outcome.

Use of ECMO has dramatically increased in the past decade. Neurological complications can be devastating. Data supporting the use of cEEG with ECMO in the adult population is limited, therefore more research is needed.

We retrospectively reviewed data from a cohort of 50 consecutive patients undergoing ECMO and cEEG at a single academic medical center in the US between 12/2016 and 7/2020.

Patients were 48 +/- 13 (mean +/- SD) years of age and 37/50 (74%) were men. ECMO types included V-V (n=15), V-A (n=19), and eCPR (n=16). No patient exhibited electrographic seizures. All (6/6) patients with good outcomes (CPC 1-2) at discharge had a reactive EEG; 24/44 (55%) of patients with poor outcomes (CPC 3-5) at discharge also had a reactive EEG. One-fifth (10/50 [20%]) of patients had sporadic epileptiform discharges (SED) and/or rhythmic or period patterns (RPP), of which 90% had poor outcome at discharge. Overall, 15/50 (30%) patients had adverse neurological events on neuroimaging: 5 had ischemic stroke; 5 had intracranial hemorrhage; 6 had global hypoxic-ischemic injury. Of the 9 individual patients with focal pathology, 44% (4/9) had focal slowing and/or attenuation of faster frequencies, and 44% (4/9) were found to have SED and/or RPP.

In this single center study, the rate of electrographic seizures during ECMO was significantly lower than reported for other ICU populations. However, our findings support existing literature that suggest EEG reactivity may predict good outcome. cEEG may be a useful tool to monitor for the occurrence of adverse neurological events during ECMO, but further prospective study is needed.