Background: The current target oxygen saturation range for patients with COVID-19 recommended by the National Institutes of Health is 92-96%. Main body: This article critically examines the evidence guiding current target oxygen saturation recommendation for COVID-19 patients, and raises important concerns in the extrapolation of data from the two studies stated to be guiding the recommendation. Next, it examines the influence of hypoxia on upregulation of ACE2 (target receptor for SARS-CoV-2 entry) expression, with supporting transcriptomic analysis of a publicly available gene expression profile dataset of human renal proximal tubular epithelial cells cultured in normoxic or hypoxic conditions. Finally, it discusses potential implications of specific clinical observations and considerations in COVID-19 patients on target oxygen saturation, such as diffuse systemic endothelitis and microthrombi playing an important pathogenic role in the wide range of systemic manifestations, exacerbation of hypoxic pulmonary vasoconstriction in the setting of pulmonary vascular endothelitis/microthrombi, the phenomenon of "silent hypoxemia" with some patients presenting to the hospital with severe hypoxemia disproportional to symptoms, and overburdened health systems and public health resources in many parts of the world with adverse implications on outpatient monitoring and early institution of oxygen supplementation. Conclusions: The above factors and analyses, put together, call for an urgent exploration and re-evaluation of target oxygen saturation in COVID-19 patients, both in the inpatient and outpatient settings. Until data from such trials become available, where possible, it may be prudent to target an oxygen saturation at least at the upper end of the recommended 92-96% range in COVID-19 patients both in the inpatient and outpatient settings (in patients that are normoxemic at pre-COVID baseline). Home pulse oximetry, tele-monitoring, and earlier institution of oxygen supplementation for hypoxemic COVID-19 outpatients could be beneficial, where public health resources allow for their implementation.

Background : Patients hospitalized for severe COVID-19 infection are at risk for in-hospital cardiac arrest (IHCA). It is unknown whether certain characteristics of cardiac arrest care and outcomes of IHCAs during the COVID-19 pandemic differed compared to a pre-COVID-19 period. Methods : All patients who experienced an IHCA at our hospital from March 1st through May 15th 2020, during the peak of the COVID-19 pandemic, and those who had an IHCA from January 1st 2019 to December 31st 2019 were identified. All patient data was extracted from our hospital's Get With The Guidelines-Resuscitation (GWTG-R) registry, a prospective hospital-based archive of IHCA data. Baseline characteristics of patients, interventions and overall outcomes of IHCAs during the COVID-19 pandemic were compared to IHCAs in 2019, prior to the COVID-19 pandemic. Results : There were 125 IHCAs during a 2.5-month period at our hospital during the peak of the COVID-19 pandemic compared to 117 IHCAs in all of 2019. IHCAs during the COVID-19 pandemic occurred more often on general medicine wards than in intensive care units (46% vs 33%; 19% vs 60% in 2019, p<0.001), were overall shorter in duration (median time of 11 min (8.5-26.5) vs 15 min (7.0-20.0), p=0.001), led to fewer endotracheal intubations (52% vs 85%, p<0.001) and had overall worse survival rates (3% vs 13%, p=0.007) compared to IHCAs prior to the COVID-19 pandemic. Conclusions : Patients who experienced an IHCA during the COVID-19 pandemic had overall worse survival compared to those who had an IHCA prior to the COVID-19 pandemic. Our findings highlight important differences between these two time periods. Further study is needed on cardiac arrest care in patients with COVID-19.

Together, chronic obstructive pulmonary disease (COPD) and asthma account for the most common non-infectious respiratory pathologies. Conflicting preliminary studies have shown varied effect for COPD and asthma as prognostic factors for mortality in coronavirus disease 2019 (COVID-19). The aim of this study was to explore the association of COPD and asthma with in-hospital mortality in patients with COVID-19 by systematically reviewing and synthesizing with a meta-analysis the available observational studies. MEDLINE, Scopus, and medRxiv databases were reviewed. A random-effects model meta-analysis was used, and I-square was utilized to assess for heterogeneity. In-hospital mortality was defined as the primary endpoint. Sensitivity and meta-regression analyses were performed. Thirty studies with 21,309 patients were included in this meta-analysis (1465 with COPD and 633 with asthma). Hospitalized COVID-19 patients with COPD had higher risk of death compared to those without COPD (OR: 2.29; 95% CI: 1.79–2.93; I2 59.6%). No significant difference in in-hospital mortality was seen in patients with and without asthma (OR: 0.87; 95% CI: 0.68–1.10; I2 0.0%). The likelihood of death was significantly higher in patients with COPD that were hospitalized with COVID-19 compared to patients without COPD. Further studies are needed to assess whether this association is independent or not. No significant difference was demonstrated in COVID-19-related mortality between patients with and without asthma.