Background: New controversies have raised on brain death (BD) diagnosis when lesions are localized in the posterior fossa. Objective: To discuss the particularities of diagnosis BD in patients with posterior fossa lesions. Material and Methods. The author made a systematic review of literature on this topic. Results and Conclusions: A supratentorial brain lesion usually produces a rostrocaudal transtentorial brain herniation, resulting in forebrain and brainstem loss of function. In secondary brain lesions [i.e., cerebral hypoxia], the brainstem is also affected like the forebrain. Nevertheless, some cases complaining posterior fossa lesions [i.e., basilar artery thrombotic infarcts, or hemorrhages of the brainstem and/or cerebellum] may retain intracranial blood flow and EEG activity. In this article I discuss that if a posterior fossa lesion does not produce an enormous increment of intracranial pressure, a complete intracranial circulatory arrest does not occur, explaining the preservation of EEG activity, evoked potentials, and autonomic function. I also address Jahi McMath, who was declared braindead, but ancillary tests, performed 9 months after initial brain insult, showed conservation of intracranial structures, EEG activity, and autonomic reactivity to “Mother Talks” stimulus, rejecting the diagnosis of BD. Jahi McMath’s MRI study demonstrated a huge lesion in the pons. Some authors have argued that in patients with primary brainstem lesions it might be possible to find a in some cases partial recover of consciousness, even fulfilling clinical BD criteria. This was the case in Jahi McMath.

Lewis et al. published an important and timely necessary article about the determination of death by neurological criteria, revising the Uniform Determination of Death.The acceptance of brain death (BD) has been progressively accepted beginning at the late 1950s. Nonetheless, contentious brain-death cases have recently raised new controversies about the diagnosis of BD, such as the Jahi McMath case, extensively covered by the US and international press. Jahi McMath meant a terrible tragedy for her and her family. But further than this gloomy story, the case has also raised confusion and challenging qualms about a fundamental query: how we confirm whether a person is dead or alive? Since 1981, the Uniform Determination of Death Act (UDDA) has served as the legal foundation for the medical practice of determining death. But, although death by neurologic criteria is considered legal death throughout the United States, several recent lawsuits have quizzed the rightfulness the authority of the UDDA to declare death by neurological criteria. This issue explains the importance of Lewis’s et al. paper. In this article I want to present the historical procedure for issuing a law in Cuba for the determination and certification of death. Of course, it is impossible to compare our country with USA. Cuba is a small and developing country, in which a law encompasses a national scenery, in contrast with USA, a multistate nation.

Covid-19 pandemic has captivated scientists to investigate if this new disease can affect the central nervous system (CNS). The most challenging symptoms of Covid-19 are related to respiratory distress, and most patients admitted in intensive care units cannot breathe by their own. Therefore, a crucial question is if respiratory distress can be partially explained by the CNS affection. SARS-Cov-2 is a beta-coronavirus that shares high similarities with SARS-CoV. The infection of SARS‐CoV has been reported in the brains from both patients and experimental animals, where the brainstem was heavily infected. Those coronaviruses have been able to invade the brainstem via a synapse‐connected route to the medullary respiratory center, where the infected regions included the nucleus of the solitary tract and nucleus ambiguous. The vagal afferent nerves from receptors in the lung communicate with the medulla and pons respiratory control centers to coordinate inspiration and expiration. This suggests that neuroinvasion of SARS‐CoV‐2 might play a role in the acute respiratory failure of Covid-19. Therefore, acute respiratory distress in Covid-19 can be partially explained by brainstem dysfunction, suggesting the needs of more specific and aggressive treatments with the direct participation of neurologists and neurointensivists.

SARS-CoV-2 (CoV-2) is a coronavirus which is causing the actual COVID-19 pandemic. The disease caused by 2019 new coronavirus (2019-nCoV) was named coronavirus disease-19 (COVID-19) by the World Health Organization in February 2020. Primary non-specific reported symptoms of 2019-nCoV infection at the prodromal phase are malaise, fever, and dry cough. The most commonly reported signs and symptoms are fever (98%), cough (76%), dyspnea (55%), and myalgia or fatigue (44%). Nonetheless, recent reports suggest an association between COVID-19 and altered olfactory and taste functions, although smell seems to be more affected than taste. These associations of smell and taste dysfunctions and CoV-2 are consistent with case reports describing a patient with SARS with long term anosmia after recovery from respiratory distress, with the observation that olfactory function is commonly altered after infection with endemic coronaviruses, and with data demonstrating that intentional experimental infection of humans with CoV-299 raises the thresholds at which odors can be detected. Post-viral anosmia and is one of the leading causes of loss of sense of smell in adults, accounting for up to 40% cases of anosmia. Viruses that give rise to the common cold are well known to cause post-infectious loss, and over 200 different viruses are known to cause upper respiratory tract infections. I reviewed the possible mechanisms of smell and taste loss in COVID-19. I concluded that since the existence of such a relationship is likely, it is highly recommended that those patients who experience complications such as smell and/or taste loss, even as unique symptoms, should be considered as potential SARS-CoV-2 virus carriers.