Tracheal intubation in coronavirus disease 2019 (COVID-19) patients creates a risk to physiologically compromised patients and to attending healthcare providers. Clinical information on airway management and expert recommendations in these patients are urgently needed. By analysing a two-centre retrospective observational case series from Wuhan,

Coronavirus Disease 2019 (COVID-19)

While the antibody response to SARS-CoV-2 has been extensively studied in blood, relatively little is known about the mucosal immune response and its relationship to systemic antibody levels. Since SARS-CoV-2 initially replicates in the upper airway, the antibody response in the oral cavity is likely an important parameter that influences the course of infection. We developed enzyme linked immunosorbent assays to detect IgA and IgG antibodies to the SARS-CoV-2 spike protein (full length trimer) and its receptor binding domain (RBD) in serum (n=496) and saliva (n=90) of acute and convalescent patients with laboratory-diagnosed COVID-19 ranging from 3-115 days post-symptom onset (PSO), compared to negative controls. Anti-CoV-2 antibody responses were readily detected in serum and saliva, with peak IgG levels attained by 16-30 days PSO. Whereas anti-CoV-2 IgA antibodies rapidly decayed, IgG antibodies remained relatively stable up to 115 days PSO in both biofluids. Importantly, IgG responses in saliva and serum were correlated, suggesting that antibodies in the saliva may serve as a surrogate measure of systemic immunity.

Nucleus taenia (Tn) in birds is a discrete component of a loosely defined archistriatal structure, the posterior and medial archistriatum. By virtue of its hypothalamic projections, the posterior and medial archistriatum is thought to be an avian homolog of the amygdala in mammals. A recent fluorogold (FG) study of avian hippocampus revealed backfilled labels in nucleus Tn, suggesting that this nucleus may indeed be the homolog of mammalian amygdala. In the present study, we sought to characterize nucleus Tn in terms of its connections and function. We used the anterograde tracers Phaseolus vulgaris leucoagglutinin (PHAL) and biotinylated dextran amine (BDA) to map the efferent projections of Tn. The retrograde tracers FG and BDA were used to corroborate the efferent projections and to explore the pattern of afferent inputs to Tn. Finally, we explored the role of Tn in social behavior by observing behavioral changes associated with electrolytic lesions to Tn. The subjects of our studies were ring doves and European starlings, representing two avian orders. When a deposit of anterograde tracer was centered in Tn, it revealed projections to the hypothalamus, following the course of the hypothalamic-occipitomesencephalic tract previously reported in pigeons. The projections were bilateral in ring doves and ipsilateral in starlings. The BDA injections in the archistratum intermedium, lateral to Tn, did not yield the same projectional pattern. Together with corroborative data from FG retrograde experiments, these findings suggest that Tn is probably the primary origin of the hypothalamic projection. A robust projection to the hyperstriatal region was present along the lateral wall of the lateral ventricle, continuing into the anteroventral pole of the ventricle. Highly arborized terminal fields were found all along this pathway, notably in the medial parolfactory lobe (corresponding to the basal ganglia) and along the dorsal roof of the rostral hyperstriatum ventrale just ventral to the laminal frontalis superior (in ring doves) and the lamina frontalis suprema (in starlings). Projections to the hippocampal complex were mostly restricted to the parahippocampus. The FG data suggest the presence of afferent projections from the ovoidais shell and nucleus subrotundus region, the hippocampal complex in both species, and high vocal nucleus in starlings. Behavioral effects of Tn lesions suggest that nucleus taenia is involved in the control of social behavior through its influence on the affective state. Nucleus taenia thus exhibits many of the structural and functional features of the amygdaloid complex in mammals – that is, subcortical sensory inputs, hippocampal complex connections, and a functional role in adaptive patterns of social behavior.

The outbreak of the new Coronavirus disease, COVID-19, has been involved in 77,262 cases in China as well as in 27 other countries as of February 24, 2020. Because the virus is novel to human beings, and there is no vaccine yet available, every individual is susceptible and can become infected. Healthcare workers are at high risk, and unfortunately, more than 3,000 healthcare workers in China have been infected. Anesthesiologists are among healthcare workers who are at an even higher risk of becoming infected because of their close contact with infected patients and high potential of exposure to respiratory droplets or aerosol from their patients’ airways. In order to provide healthcare workers with updated recommendations on the management of patients in the perioperative setting as well as for emergency airway management outside of the operating room, the two largest anesthesia societies, the Chinese Society of Anesthesiology (CSA) and the Chinese Association of Anesthesiologists (CAA) have formed a task force to produce the recommendations. The task force hopes to help healthcare workers, particularly anesthesiologists, optimize the care of their patients and protect patients, healthcare workers, and the public from becoming infected. The recommendations were created mainly based on the practice and experience of anesthesiologists who provide care to patients in China. Therefore, adoption of these recommendations outside of China must be done with caution, and the local environment, culture, uniqueness of the healthcare system, and patients’ needs should be considered. The task force will continuously update the recommendations and incorporate new information in future versions.