Neurological complications of critically ill COVID-19 patients

Abstract
Purpose of review COVID-19 and systemic critical illness are both associated with neurological complications. We provide an update on the diagnosis and critical care management of adult patients with neurological complications of COVID-19. Recent findings Large prospective multicentre studies conducted in the adult population over the last 18 months improved current knowledge on severe neurological complications of COVID-19. In COVID-19 patients presenting with neurological symptoms, a multimodal diagnostic workup (including CSF analysis, brain MRI, and EEG) may identify different syndromes associated with distinct trajectories and outcomes. Acute encephalopathy, which represents the most common neurological presentation of COVID-19, is associated with hypoxemia, toxic/metabolic derangements, and systemic inflammation. Other less frequent complications include cerebrovascular events, acute inflammatory syndromes, and seizures, which may be linked to more complex pathophysiological processes. Neuroimaging findings include infarction, haemorrhagic stroke, encephalitis, microhaemorrhages and leukoencephalopathy. In the absence of structural brain injury, prolonged unconsciousness is usually fully reversible, warranting a cautious approach for prognostication. Advanced quantitative MRI may provide useful insights into the extent and pathophysiology of the consequences of COVID-19 infection including atrophy and functional imaging changes in the chronic phase. Summary Our review highlights the importance of a multimodal approach for the accurate diagnosis and management of complications of COVID-19, both at the acute phase and in the long-term.