Respiratory function and its multiple implicated mechanisms have the objective to control pressures of carbon dioxide and oxygen, and adequate homeostasis by control of the concentration of hydrogen emissions. The neural role of respiratory physiology is important to maintain the said functioning. Interestingly, two sets of neuronal networks present within the brainstem is crucial for the generation of respiratory rhythm.1 Literature suggests that neurotropism is one of the common features of coronaviruses. It is prudent to identify if SARS CoV-2 affects the respiratory control mechanisms at the brainstem and lead to complications in addition to primary respiratory damage.2 SARS-CoV-2 can enter the brain directly via the cribriform plate or the hematogenous route.3 , 4 Studies indicate that SARS-CoV probably enters the brain through olfactory bulb and spread to thalamus and brainstem.5 There are reports which suggest that involvement of pontine and medullary centres by SARS-CoV-2 is a mechanism implicated in potential central respiratory failure complicating primary pulmonary injury.2 Interestingly, 62.4% of severe cases of SARS-CoV-2 do not present with dyspnea.6 Since dyspnea is the perception of shortness of breath, this could be due to damage of sensory afferents in brain stem carrying signals from peripheral receptors. Recently a case report published illustrated brainstem dysfunction due to rhombencephalitis in a patient with acute COVID-19.6 The use of preclinical models will be especially useful to understand the pathobiology of the coronavirus in the brain stem.7 Therefore, patients with SARS-CoV-2 with neurological symptoms must be followed up closely as they can have further deterioration in their respiratory function.8 It is also important to find the way SARS-CoV-2 invade the brain, i.e. direct, indirect, vascular or through peripheral nerves.9 We propose the use of a neuroimaging protocol as soon as possible after the removal of mechanical ventilation to characterize the injury at the level of neural structures. Further insight can be obtained in these questions by using other neurological investigations and studies on neural architecture in autopsy studies.
Declaration of Competing Interest
The authors have no conflicts of interest relevant to this article.
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