ABSTRACT
Objective: To describe the autonomic and SNC manifestations of patients with coronavirus disease 2019 (COVID-19) and happy hypoxemia. Background: Happy hypoxemia is the absence of dyspnea despite low oxygen saturation. Several hypotheses for its occurrence include potential viral neuroinvasion, autonomic dysfunction, and cortical ischemic damage. Design/Methods: We studied prospectively nine patients with COVID-19 who arrived at the ER with very low oxygen saturation (50-79%) and no dyspnea complaints. Patients were invited to participate and underwent a full clinical history, brain MRI with gadolinium, and 24H-Holter with spectroscopy while hospitalized and bed-ridden. We used Pearson's coefficient correlation for the correlation analysis. Results: Two patients were excluded from the study because they no longer wished to participate and one because he had FA. we analyzed six patients (66% women) with a mean age of 59 years old (47-83). Two patients had high blood pressure, one patient had a history of tuberculosis, and one had Down Syndrome. Upon arrival at the ER, the mean oxygen saturation was 67% and PaO2 59.3 (47-83). One patient (14%) complain of headache and none of anosmia or ageusia. Four patients underwent a brain MRI that showed gadolinium enhancement of the olfactory bulbs and white matter lesions. One patient also had a left insular lesion. Three patients had abnormal SDNN<100 (83ms, 30-146), and one had RMSSD <15. Vagally mediated changes reflected in HRv were significantly lower in patients with lower blood O2 saturation (SDDN p=0.002, r=.95, HF p=0.009, r=.92, LF/HF ns, -0.42). Conclusions: Patients with happy hypoxemia had decreased heart rate variability that correlated with the degree of hypoxemia, suggesting altered modulation of vagal tone and autonomic dysregulation. All the patients had olfactory bulb enhancement. In our patients, hyposmia /anosmia did not correlate with olfactory bulb hyperintensities or happy hypoxemia.
ABSTRACT
Objective: To describe the neurologic manifestations and complications of Mexican patients with confirmed coronavirus disease 2019 (COVID-19). Background: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was confirmed to have reached Mexico in February 2020. At present, Mexico is one of the most affected countries by the pandemic of COVID-19 worldwide. In the first months of the pandemic, only a few Mexican studies on COVID-19 had been reported. Scarce national data limited our understanding of the unique nuances that may occur in our setting and hindered the interpretation of evidence from other countries in the local context. Design/Methods: In March 2020, the Mexican Academy of Neurology (MAN) launched a national registry to have a clearer picture of the full spectrum of neurologic manifestations and complications of COVID-19 in Mexican patients. This online registry was available to all MAN members. Only patients with SARS-CoV-2 detected by real-time RT-PCR were included in this analysis. Results: At the end of August 2020, 89 patients (31 women, 34.8%) have been included. Their mean age was 50.5±18.8 years. Most cases were reported in central and southern regions (96%). Most patients showed respiratory symptoms (87%) and were admitted to hospital (88%). Among severe neurologic manifestations, vascular etiologies were the most commonly reported: ischemic stroke (n=17), intraparenchymal hemorrhage (n=6), and subarachnoid hemorrhage (n=4). Olfactory and gustatory dysfunctions were reported in 34 and 26 patients. Headache and delirium were reported in 54 and 18 patients. 7 patients had seizures. Meningitis and encephalitis were reported in 2 and 5 patients. 5 cases of Guillain-Barré syndrome were reported;three of them were classified as axonal variants. Neurologic sequelae were reported in 30 patients (33%). 19 (21%) patients died. Conclusions: In this nationwide registry, one in five patients with COVID-19 and neurologic manifestations died. Cerebrovascular insults were the most common severe neurologic manifestations.