Background and aims: Currently there is limited knowledge on medical comorbidities and COVID-19; we conducted a systematic review and meta-analysis to evaluate the impact of various morbidities on serious events in COVID 19. Methods: PubMed, Cochrane Central Register of Clinical Trials were searched on April 28, 2020, to extract published articles that reported the outcomes of COVID-19 patients. The search terms were "coronavirus" and "clinical characteristics". ICU admission, mechanical ventilation, ARDS, Pneumonia, death was considered serious events. The comorbidities assessed in the study were Hypertension (HTN), Diabetes mellitus (DM), Cardiovascular diseases (CVD), Chronic obstructive pulmonary disease (COPD) and Chronic Kidney disease (CKD). Subsequently, comparisons between comorbidity patient group and the non-comorbidity patient groups, in terms of serious events were made using the pooled estimates of odd's ratio (OR) Results: We identified 688 published results and 16 studies with 3994 patients were included in the systematic review. Serious events were seen in 526(13.16%) patients. Presence of hypertension with OR 2.95, diabetes mellitus with OR 3.07, Cardio vascular disease with OR 4.58, COPD with OR 6.66 and Chronic kidney disease with OR 5.32 had significant association in patients with COVID 19 on having serious events. Presence of diabetes mellitus (OR 2.78)) had a significant impact on death in COVID 19 patients with a p-value 0.004. Conclusions: Presence of medical comorbidities in COVID-19 leads to higher risk of developing serious events i.e. ICU admission, mechanical intubation and mortality. The presence of Diabetes mellitus has a significant impact on mortality rate in COVID-19 patients.

Objective This systematic review and meta-analysis were conducted to study the prevalence and pattern of sleep disturbances in children and adolescents during the COVID-19 pandemic. Methods MEDLINE, EMBASE, and Web of Science were searched for original studies describing sleep abnormalities in children and adolescents with or without pre-existing neurobehavioral disorders during the COVID-19 pandemic. The pooled estimates for various sleep abnormalities were calculated using a random-effect model. Results Of 371 articles screened, 16 studies were included. Among these, five studies were in preschool children, two were in children with pre-existing neurobehavioral disorders and the remaining were in school going children and adolescents. The outcome measures used for sleep were markedly heterogeneous across the studies. The pooled prevalence of any sleep disturbance in children during the pandemic was 54%(95%CI:50–57%). Interestingly, the prevalence in pre-school children was lower than pre-pandemic times (RR = 0.87; 95% CI:0.58–1.30) but this was not statistically significant. The pooled prevalence of children not meeting sleep recommendation was 49% (95%CI: 39–58%). Conclusion The prevalence of sleep problems in children and adolescents during the COVID-19 pandemic is alarming. Pre-school children had a trend towards relatively fewer sleep disturbances due to home confinement measures in comparison with pre-pandemic times. Sleep duration recommendations were not met in nearly half of healthy children. However, these conclusions need to be seen in light of limited literature on the topic, few included studies done in heterogenous populations, and dubious quality of inferences drawn from these studies which were predominantly online surveys. Prospero registration id CRD42020213788.

The mechanism(s) by which anesthetics reversibly suppress consciousness are incompletely understood. Previous functional imaging studies demonstrated dynamic changes in thalamic and cortical metabolic activity, as well as the maintained presence of metabolically defined functional networks despite the loss of consciousness. However, the invasive electrophysiology associated with these observations has yet to be studied. By recording electrical activity directly from the cortical surface, electrocorticography (ECoG) provides a powerful method to integrate spatial, temporal, and spectral features of cortical electrophysiology not possible with noninvasive approaches. In this study, we report a unique comprehensive recording of invasive human cortical physiology during both induction and emergence from propofol anesthesia. Propofolinduced transitions in and out of consciousness (defined here as responsiveness) were characterized by maintained large-scale functional networks defined by correlated fluctuations of the slow cortical potential (<0.5 Hz) over the somatomotor cortex, present even in the deeply anesthetized state of burst suppression. Similarly, phase-power coupling between θ-and γ-range frequencies persisted throughout the induction and emergence from anesthesia. Superimposed on this preserved functional architecture were alterations in frequency band power, variance, covariance, and phase-power interactions that were distinct to different frequency ranges and occurred in separable phases. These data support that dynamic alterations in cortical and thalamocortical circuit activity occur in the context of a larger stable architecture that is maintained despite anesthetic-induced alterations in consciousness.cortical networks | human cortex | gamma rhythms E very year millions of people undergo general anesthesia, yet the mechanism(s) by which widely used clinical anesthetics reversibly ablate consciousness remains incompletely understood (1). Moreover, the manner in which the brain is able to tolerate global pharmacologic suppression, yet still maintain memories and resume complex cortical interactions that define a person's cognition after removal of this suppression, also remains unknown. Thus far, the majority of studies in humans have used noninvasive methods such as functional imaging and electroencephalography (EEG) to arrive at the current understanding. To date, positron emission tomography (PET) and functional magnetic resonance imaging (fMRI) studies show that there is a complex interplay between and within the thalamus and the cortex. These studies demonstrate that the thalamus is a common site of deactivation during induction by various anesthetic agents (2,3), that there appears to be a disruption of thalamo-cortical and cortico-cortical connectivity (4, 5), and that specific regions of association cortices show enhanced deactivation with certain anesthetics (6, 7). In parallel with these dynamic interactions, there also appear to be physiologic elements that are invariant and do not change wi...

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Electrocorticography (ECoG) has emerged as a new signal platform for brain-computer interface (BCI) systems. Classically, the cortical physiology that has been commonly investigated and utilized for device control in humans has been brain signals from sensorimotor cortex. Hence, it was unknown whether other neurophysiological substrates, such as the speech network, could be used to further improve on or complement existing motor-based control paradigms. We demonstrate here for the first time that ECoG signals associated with different overt and imagined phoneme articulation can enable invasively monitored human patients to control a one-dimensional computer cursor rapidly and accurately. This phonetic content was distinguishable within higher gamma frequency oscillations and enabled users to achieve final target accuracies between 68 and 91% within 15 minutes. Additionally, one of the patients achieved robust control using recordings from a microarray consisting of 1 mm spaced microwires. These findings suggest that the cortical network associated with speech could provide an additional cognitive and physiologic substrate for BCI operation and that these signals can be acquired from a cortical array that is small and minimally invasive.