The recent development of the pandemic due to the SARS-CoV-2 virus has showed that a substantial proportion of patients developed a severe condition requiring critical care, notably because of acute respiratory distress syndrome requiring mechanical ventilation and deep sedation. Outside of this coronavirus infection, this situation is classically associated with a high prevalence of brainstem dysfunction, even in the absence of brain injury. This dysfunction, either structural or functional, can be detected using appropriate clinical tools such as the BRASS score and/or using the quantitative analysis of EKG and EEG. Crucially, brainstem dysfunction is associated not only with ICU complications such as delirium, but also with a poorer survival.
Moreover, some reports of encephalitis cases and the presence of anosmia/agueusia raised the question of whether the virus could directly invade the central nervous system.
For these two reasons, it is reasonable to assume that brainstem dysfunction is particularly prevalent in critically ill patients infected with SARS-CoV-2 and that this dysfunction could be one of the major determinant of patients outcome.