The Clinical Utility of Relative Bradycardia for Identifying Cases of Coronavirus Disease 2019 Pneumonia: A Retrospective Pneumonia Cohort Study.

Objective Both coronavirus disease 2019 (COVID-19) pneumonia and relative bradycardia are common conditions among clinicians; however, the association between these has not been well studied. The present study assessed whether or not relative bradycardia on admission was more predominant in patients with COVID-19 pneumonia than in those with other infectious pneumonia. Methods For this single-center, retrospective cohort study, we collected data through electronic medical records and examined the occurrence of relative bradycardia on admission. We used logistic regression analyses to compare outcomes with and without relative bradycardia on admission. The primary outcome was COVID-19 pneumonia. The secondary outcome was hypoxemia during the hospital stay. We performed multivariable regression with adjusting for the effects of age, sex, healthcare-associated pneumonia, body mass index, Charlson comorbidity index, and bilateral infiltration on computed tomography (CT) as confounding factors. Patients Adult patients with new-onset hospitalized infectious pneumonia confirmed by CT between January 1, 2020, and July 31, 2021. Results This study included 395 participants. On admission, 87 (22.0%) participants exhibited relative bradycardia, and 302 (76.5%) participants had COVID-19. Relative bradycardia on admission was not significantly associated with COVID-19 pneumonia [adjusted odds ratio (OR) 1.32; 95% confidence interval (CI) 0.49-3.54, p=0.588] but was associated with hypoxemia (adjusted OR 4.74; 95%CI 2.64-8.52, p<0.001). Conclusion The study results showed that relative bradycardia on admission was not associated with COVID-19 in cases of infectious pneumonia. However, relative bradycardia may be associated with the incidence of hypoxemia in pneumonia.

Disparities in COVID-19 incidence and fatality rates at high-altitude.

Background: SARS-CoV-2 has affected every demography disproportionately, including even the native highland populations. Hypobaric-hypoxic settings at high-altitude (HA, >2,500 masl) present an extreme environment that impacts the survival of permanent residents, possibly including SARS-CoV-2. Conflicting hypotheses have been presented for COVID-19 incidence and fatality at HA. Objectives: To evaluate protection or risk against COVID-19 incidence and fatality in humans under hypobaric-hypoxic environment of high-altitude (>2,501 masl). Methods: Global COVID-19 data of March 2020-21, employed from official websites of the Indian Government, John Hopkins University, and Worldometer were clustered into 6 altitude categories. Clinical cofactors and comorbidities data were evaluated with COVID-19 incidence and fatality. Extensive comparisons and correlations using several statistical tools estimated the risk and protection. Results: Of relevance, data analyses revealed four distinct responses, namely, partial risk, total risk, partial protection, and total protection from COVID-19 at high-altitude indicating a mixed baggage and complexity of the infection. Surprisingly, it included the countries within the same geographic region. Moreover, body mass index, hypertension, and diabetes correlated significantly with COVID-19 incidence and fatality rate (P ≤ 0.05). Conclusions: Varied patterns of protection and risk against COVID-19 incidence and fatality were observed among the high-altitude populations. It is though premature to generalize COVID-19 effects on any particular demography without further extensive studies.

Hospitalised COVID-19 outcomes are predicted by hypoxaemia and pneumonia phenotype irrespective of the timing of their emergence.

Despite the known clinical importance of hypoxemia and pneumonia, there is a paucity of evidence for these variables with respect to risk of mortality and short-term outcomes among those hospitalised with COVID-19. OBJECTIVE: Describe the prevalence and clinical course of patients hospitalised with COVID-19 based on oxygenation and pneumonia status at presentation and determine the incidence of emergent hypoxaemia or radiographic pneumonia during admission. METHODS: A retrospective study was conducted using a Canadian regional registry. Patients were stratified according to hypoxaemia/pneumonia phenotype and prevalence. Clinical parameters were compared between phenotypes using χ2 and one-way Analysis of variance (ANOVA). Cox analysis estimated adjusted Hazard Ratios (HR) for associations between disease outcomes and phenotypes. RESULTS: At emergency department (ED) admission, the prevalence of pneumonia and hypoxaemia was 43% and 50%, respectively, and when stratified to phenotypes: 28.2% hypoxaemia+/pneumonia+, 22.2% hypoxaemia+/pneumonia-, 14.5% hypoxaemia-/pneumonia+ and 35.1% hypoxaemia-/pneumonia-. Mortality was 31.1% in the hypoxaemia+/pneumonia- group and 26.3% in the hypoxaemia+/pneumonia+ group. Hypoxaemia with pneumonia and without pneumonia predicted higher probability of death. Hypoxaemia either <24 hours or ≥24 hours after hospitalisation predicted higher mortality and need for home oxygen compared with those without hypoxaemia. Patients with early hypoxaemia had higher probability of Intensive care unit (ICU) admission compared with those with late hypoxaemia. CONCLUSION: Mortality in COVID-19 infection is predicted by hypoxaemia with or without pneumonia and was greatest in patients who initially presented with hypoxaemia. The emergence of hypoxaemia was predicted by radiographic pneumonia. Patients with early and emergent hypoxaemia had similar mortality but were less likely to be admitted to ICU. There may be delayed identification of hypoxaemia, which prevents timely escalation of care.

Demographic and clinical profile of patients suffering prolonged severe hypoxia in COVID-19.

BACKGROUND: Coronavirus disease 2019 (COVID-19) may result in rapid onset of hypoxemic respiratory failure. This study aimed to characterize the factors and outcomes associated with prolonged hypoxia in patients with COVID-19. Prolonged severe hypoxia (PSH) was defined as hypoxia requiring ≥6 L/min of oxygen by nasal cannula or equivalent for more than 10 days. RESEARCH DESIGN AND METHODS: This study was designed as a single-center retrospective analysis. Multivariable logistic regression was utilized to assess factors associated with PSH. RESULTS: The sample included 554 patients with 117 (21%) having PSH. Median length of stay of patients with PSH was significantly longer (median IQR: 18 days vs 6 days, p < 0.0001). Patients with PSH had significantly higher rates of venous thromboembolism (p < 0.0001) and major bleeding (p < 0.004). The presence of cirrhosis (OR 3.32, 95% CI [1.02 to 10.83]) and hypertension (OR 1.99, 95% CI [1.12 to 3.53]) were independently associated with PSH, while outpatient use of anti-platelet agents had an inverse association (OR 0.57, 95% CI [0.36 to 0.91]). CONCLUSION: PSH is associated with increased length of stay, morbidity, and mortality. Hypertension and liver cirrhosis were significantly associated with higher odds of PSH, while use of anti-platelet therapy had a protective effect.

Respiratory Drive, Dyspnea, and Silent Hypoxemia: A Physiological Review in the Context of COVID-19.

Infection with SARS-CoV-2 in select individuals results in viral sepsis, pneumonia, and hypoxemic respiratory failure, collectively known as COVID-19. In the early months of the pandemic, the combination of novel disease presentation, enormous surges of critically ill patients, and severity of illness lent to early observations and pronouncements regarding COVID-19 that could not be scientifically validated owing to crisis circumstances. One of these was a phenomenon referred to as "happy hypoxia." Widely discussed in the lay press, it was thought to represent a novel and perplexing phenomenon: severe hypoxemia coupled with the absence of respiratory distress and dyspnea. Silent hypoxemia is the preferred term describing an apparent lack of distress in the presence of hypoxemia. However, the phenomenon is well known among respiratory physiologists as hypoxic ventilatory decline. Silent hypoxemia can be explained by physiologic mechanisms governing the control of breathing, breathing perception, and cardiovascular compensation. This narrative review examines silent hypoxemia during COVID-19 as well as hypotheses that viral infection of the central and peripheral nervous system may be implicated. Moreover, the credulous embrace of happy hypoxia and the novel hypotheses proposed to explain it has exposed significant misunderstandings among clinicians regarding the physiologic mechanisms governing both the control of breathing and the modulation of breathing sensations. Therefore, a substantial focus of this paper is to provide an in-depth review of these topics.

Predictors of silent hypoxia in hospitalized patients with COVID-19 in Japan.

INTRODUCTION: Silent hypoxia (SH) is common in patients with coronavirus disease (COVID-19) in Japan and other countries. Early identification of SH is important as more treatment options for COVID-19 have become available. This study aimed to identify predictors of SH using a nationwide COVID-19 registry of hospitalized patients. METHODS: Adult patients who were admitted to hospital with COVID-19 between January 2020 and June 2021 and who were hypoxic on admission (SpO2: 70-93%), not transferred from another facility, and who did not have disturbance of consciousness, confusion, or dementia, were included. SH was defined as hypoxia in the absence of shortness of breath/dyspnea upon admission. Predictors of SH were identified using univariable and multivariable logistic regression. RESULTS: The study included 1904 patients, of whom 990 (52%) satisfied the criteria for SH. Compared to patients without SH, patients with SH were older, more likely to be female, and had a slightly higher SpO2 on admission. Compared to patients without SH, patients with SH had a lower prevalence of chronic lung disease (CLD) other than chronic obstructive pulmonary disease (COPD), asthma, and obesity. Multivariable analysis revealed that the independent predictors of SH were older age, a shorter interval from symptom onset to admission, higher SpO2, and an absence of CLD or COPD. CONCLUSIONS: The absence of underlying lung disease and older age were important predictors of SH. The results of this study, which is the largest such study reported to date in Japan, may help clarify the mechanism of SH.

Impact of covid-19 on long-term oxygen therapy 2020: A nationwide study in Sweden.

INTRODUCTION: Covid-19 can cause chronic hypoxic respiratory failure, but the impact on the need for long-term oxygen therapy (LTOT) is unknown. The aim was to investigate change in incidence and characteristics of patients starting LTOT in Sweden 2020 after the outbreak of the pandemic. MATERIAL AND METHODS: Population-based observational study using data from the National Registry for Respiratory Failure (Swedevox) and from a survey to all centres prescribing LTOT in Sweden. Swedevox data provided information on incidence of LTOT and characteristics of patients starting LTOT during 2015-2020. RESULTS: Between March-Dec 2020, 131 patients started LTOT due to covid-19, corresponding to 20.5% of incident LTOT in Sweden. Compared with 2015-19, the total number of patients starting LTOT did not increase. No significant differences in patient characteristics or underlying causes of hypoxemia were found between patients starting LTOT during 2020 compared 2015-2019. The majority of the LTOT centres estimated that, since the start of the pandemic, the incidence of LTOT was unchanged and the time devoted for LTOT work was the same or slightly less. CONCLUSIONS: Covid-19 caused one fifth of all LTOT starts during the pandemic in 2020. The LTOT incidence overall did not increase possibly due to reduction in other infections.

Risk factors associated with asymptomatic hypoxemia among COVID-19 patients: a retrospective study using the nationwide Japanese registry, COVIREGI-JP.

Deaths of home-care patients with coronavirus disease (COVID-19) have become a social problem. One of their causes is hypoxemia without dyspnea which delays seeking medical attention. This was a retrospective study including patients registered in the COVID-19 Registry Japan, in which hospitalized patients with COVID-19 in 227 participating healthcare facilities were enrolled. The enrolled patients were divided into two groups: non-dyspneic patients with a peripheral capillary oxygen saturation (SpO2) ≤ 93% on admission (the hypoxemia without dyspnea group) and non-dyspneic patients with an SpO2> 93% (the control group). We conducted a multivariate logistic regression analysis to identify the factors associated with hypoxemia without dyspnea. 21544 patients were enrolled, 1035 (4.8%) patients were in the hypoxemia without dyspnea group, and 20509 (95.2%) patients were in the control group. The median respiratory rate (RR) of the hypoxemia without dyspnea group was higher than that of the control group (31/min vs. 18/min, p < 0.001). Age> 65, male, body mass index> 25, smoking, chronic obstructive pulmonary disease, other chronic lung disease, and diabetes mellitus were the independent factors associated with hypoxemia without dyspnea. Patients with those background should be closely monitored. RR is an important indicator of hypoxemia, even in the absence of dyspnea.

Prevalence of hypoxaemia in children with pneumonia in low-income and middle-income countries: a systematic review and meta-analysis.

BACKGROUND: Pneumonia accounts for around 15% of all deaths of children younger than 5 years globally. Most happen in resource-constrained settings and are potentially preventable. Hypoxaemia is one of the strongest predictors of these deaths. We present an updated estimate of hypoxaemia prevalence among children with pneumonia in low-income and middle-income countries. METHODS: We conducted a systematic review using the following key concepts "children under five years of age" AND "pneumonia" AND "hypoxaemia" AND "low- and middle-income countries" by searching in 11 bibliographic databases and citation indices. We included all articles published between Nov 1, 2008, and Oct 8, 2021, based on observational studies and control arms of randomised and non-randomised controlled trials. We excluded protocol papers, articles reporting hypoxaemia prevalence based on less than 100 pneumonia cases, and articles published before 2008 from the review. Quality appraisal was done with the Joanna Briggs Institute tools. We reported pooled prevalence of hypoxaemia (SpO2 <90%) by classification of clinical severity and by clinical settings by use of the random-effects meta-analysis models. We combined our estimate of the pooled prevalence of pneumonia with a previously published estimate of the number of children admitted to hospital due to pneumonia annually to calculate the total annual number of children admitted to hospital with hypoxaemic pneumonia. FINDINGS: We identified 2825 unique records from the databases, of which 57 studies met the eligibility criteria: 26 from Africa, 23 from Asia, five from South America, and four from multiple continents. The prevalence of hypoxaemia was 31% (95% CI 26-36; 101 775 children) among all children with WHO-classified pneumonia, 41% (33-49; 30 483 children) among those with very severe or severe pneumonia, and 8% (3-16; 2395 children) among those with non-severe pneumonia. The prevalence was much higher in studies conducted in emergency and inpatient settings than in studies conducted in outpatient settings. In 2019, we estimated that over 7 million children (95% CI 5-8 million) were admitted to hospital with hypoxaemic pneumonia. The studies included in this systematic review had high τ2 (ie, 0·17), indicating a high level of heterogeneity between studies, and a high I2 value (ie, 99·6%), indicating that the heterogeneity was not due to chance. This study is registered with PROSPERO, CRD42019126207. INTERPRETATION: The high prevalence of hypoxaemia among children with severe pneumonia, particularly among children who have been admitted to hospital, emphasises the importance of overall oxygen security within the health systems of low-income and middle-income countries, particularly in the context of the COVID-19 pandemic. Even among children with non-severe pneumonia that is managed in outpatient and community settings, the high prevalence emphasises the importance of rapid identification of hypoxaemia at the first point of contact and referral for appropriate oxygen therapy. FUNDING: UK National Institute for Health Research (Global Health Research Unit on Respiratory Health [RESPIRE]; 16/136/109).

Association between Prehospital Hypoxemia and Admission to Intensive Care Unit during the COVID-19 Pandemic: A Retrospective Cohort Study.

Background and Objectives: The aim of this study was to assess the association between prehospital peripheral oxygen saturation (SpO2) and intensive care unit (ICU) admission in confirmed or suspected coronavirus disease 19 (COVID-19) patients. Materials and Methods: We carried out a retrospective cohort study on patients requiring prehospital intervention between 11 March 2020 and 4 May 2020. All adult patients in whom a diagnosis of COVID-19 pneumonia was suspected by the prehospital physician were included. Patients who presented a prehospital confounding respiratory diagnosis and those who were not eligible for ICU admission were excluded. The main exposure was "Low SpO2" defined as a value < 90%. The primary outcome was 48-h ICU admission. Secondary outcomes were 48-h mortality and 30-day mortality. We analyzed the association between low SpO2 and ICU admission or mortality with univariable and multivariable regression models. Results: A total of 145 patients were included. A total of 41 (28.3%) patients had a low prehospital SpO2 and 21 (14.5%) patients were admitted to the ICU during the first 48 h. Low SpO2 was associated with an increase in ICU admission (OR = 3.4, 95% CI = 1.2-10.0), which remained significant after adjusting for sex and age (aOR = 5.2, 95% CI = 1.8-15.4). Mortality was higher in low SpO2 patients at 48 h (OR = 7.1 95% CI 1.3-38.3) and at 30 days (OR = 3.9, 95% CI 1.4-10.7). Conclusions: In our physician-staffed prehospital system, first low prehospital SpO2 values were associated with a higher risk of ICU admission during the COVID-19 pandemic.

Haematological profile of COVID-19 patients from a centre in Singapore.

BACKGROUND: Haematological markers such as absolute lymphopenia have been associated with severe COVID-19 infection. However, in the literature to date, the cohorts described have typically included patients who were moderate to severely unwell with pneumonia and who required intensive care stay. It is uncertain if these markers apply to a population with less severe illness. We sought to describe the haematological profile of patients with mild disease with COVID-19 admitted to a single centre in Singapore. METHODS: We examined 554 consecutive PCR positive SARS-COV-2 patients admitted to a single tertiary healthcare institution from Feb 2020 to April 2020. In all patients a full blood count was obtained within 24 h of presentation. RESULTS: Patients with pneumonia had higher neutrophil percentages (66.5 ± 11.6 vs 55.2 ± 12.6%, p < 0.001), lower absolute lymphocyte count (1.5 ± 1.1 vs 1.9 ± 2.1 x109/L, p < 0.011) and absolute eosinophil count (0.2 ± 0.9 vs 0.7 ± 1.8 × 109/L, p = 0.002). Platelet counts (210 ± 56 vs 230 ± 61, p = 0.020) were slightly lower in the group with pneumonia. We did not demonstrate significant differences in the neutrophil-lymphocyte ratio, monocyte-lymphocyte ratio and platelet-lymphocyte ratio in patients with or without pneumonia. Sixty-eight patients (12.3%) had peripheral eosinophilia. This was more common in migrant workers living in dormitories. CONCLUSION: Neutrophilia and lymphopenia were found to be markers associated with severe COVID-19 illness. We did not find that combined haematological parameters: neutrophil-lymphocyte ratio, monocyte-lymphocyte ratio and platelet-lymphocyte ratio, had any association with disease severity in our cohort of patients with mild-moderate disease. Migrant workers living in dormitories had eosinophilia which may reflect concurrent chronic parasitic infection.

Silent Hypoxia in COVID-19: A Case Series.

BACKGROUND: The coronavirus disease 2019 (COVID-19) pandemic is an ongoing global crisis challenging the worldwide healthcare systems. Many patients present with a mismatch of profound hypoxemia and few signs of respiratory distress (i.e., silent hypoxemia). This particular clinical presentation is often cited, but data are limited. MAIN BODY: We describe dyspnea sensation as assessed by using the BORG scale in pulmonary patients admitted to the emergency room during a 4-week period and transferred to the respiratory department of Siloah Hospital, Hannover, Germany. From October 1 to November 1, 2020, 82 patients with hypoxemia defined as oxygen demand to achieve an oxygen saturation (SpO2) ≥92% were included. In 45/82 (55%) patients, SARS-CoV-2 was detected by PCR on admission. Among non-COVID patients, exacerbation of COPD was the main diagnosis (15/37, 41%). All subjects rated their perceived dyspnea using the modified Borg CR10 scale. Patients in the non-COVID group suffered from more dyspnea on the modified Borg CR10 scale (median 1, IQR: 0-2 vs. median 5, IQR: 3-6, p < 0.001). In multivariate analysis, "silent hypoxemia" as defined by the dyspnea Borg CR10 scale ≥5 was independently associated with COVID-19 and presence of severe hypocapnia with an odds ratio of 0.221 (95% confidence interval 0.054, 0.907, p 0.036). CONCLUSION: Among pulmonary patients with acute hypoxemia defined as oxygen demand, patients suffering from COVID-19 experience less dyspnea compared to non-COVID patients. "Silent" hypoxemia was more common in COVID-19 patients.

Bacterial infections and death among patients with Covid-19 versus non Covid-19 patients with pneumonia.

BACKGROUND: Many patients with Coronavirus disease-2019 (Covid-19) present with radiological evidence of pneumonia. Because it is difficult to determine co-existence of bacterial pneumonia, many of these patients are initially treated with antibiotics. We compared the rates of bacterial infections and mortality in Covid-19 patients with pulmonary infiltrates versus patients diagnosed with 'pneumonia' the year previously. METHODS: We conducted a medical record review of patients admitted with Covid-19 and a pulmonary infiltrate and compared them with patients diagnosed with pneumonia admitted in the prior year before the pandemic. Data abstracted included baseline demographics, comorbidities, signs and symptoms, laboratory and microbiological results, and imaging findings. Outcomes were bacterial infections and mortality. Patients presenting with and without Covid-19 were compared using univariable and multivariable analyses. RESULTS: There were 1398 and 1001 patients admitted through the emergency department (ED) with and without Covid-19 respectively. Compared with non-Covid-19 patients, those with Covid-19 were younger (61±18 vs. 65±25 years, P < 0.001) and had a lower Charlson Comorbidity Index (0.7 vs. 1.2, P < 0.001). Bacterial infections were present in fewer Covid-19 than non-Covid-19 patients (8% vs. 13%, P < 0.001), and most infections in Covid-19 were nosocomial as opposed to community acquired in non-Covid-19 patients. CXR was more often read as abnormal and with bilateral infiltrates in patients with Covid-19 (82% vs. 70%, P < 0.001 and 81% vs. 48%, P < 0.001, respectively). Mortality was higher in patients with Covid-19 vs. those without (15% vs. 9%, P < 0.001). Multivariable predictors (OR [95%CI]) of mortality were age (1.04 [1.03-1.05]/year), tachypnea (1.55 [1.12-2.14]), hypoxemia (2.98 [2.04-4.34]), and bacterial infection (2.80 [1.95-4.02]). Compared with non-Covid-19 patients with pneumonia, patients with Covid-19 were more likely to die (2.68 [1.97-3.63]). CONCLUSIONS: The rate of bacterial infections is lower in Covid-19 patients with pulmonary infiltrates compared with patients diagnosed with pneumonia prior to the pandemic and most are nosocomial. Mortality was higher in Covid-19 than non-Covid-19 patients even after adjusting for age, tachypnea, hypoxemia, and bacterial infection.

Association of SARS-CoV-2 placental histopathology findings with maternal-fetal comorbidities and severity of COVID-19 hypoxia.

OBJECTIVE: SARS-CoV-2 is known to impact multiple organ systems, with growing data to suggest the potential for placental infection and resultant pathology. Understanding how maternal COVID-19 disease can affect placental histopathology has been limited by small study cohorts with mild disease, review by multiple pathologists, and potential confounding by maternal-fetal comorbidities that can also influence placental findings. This study aims to identify pathologic placental findings associated with COVID-19 disease and severity, as well as to distinguish them from changes related to coexisting maternal-fetal comorbidities. METHODS: This is an observational study of 61 pregnant women with confirmed SARS-CoV-2 infection who delivered and had a placental histological evaluation at NYU Langone Health between March 19, 2020 and June 30, 2020. Primary outcomes were the prevalence of placental histopathologic features and their association with maternal-fetal comorbidities and severity of COVID-19 related hypoxia. Analysis was performed using Fisher's exact test and t-test with p < 0.05 considered significant. RESULTS: Sixty-one placentas were included in the study cohort, 71% from pregnancies complicated by at least one maternal-fetal comorbidity. Twenty-five percent of placentas were small for gestational age and 77% exhibited at least one feature of maternal vascular malperfusion. None of the histopathologic features in the examined placentas were associated with the presence of any specific maternal-fetal comorbidity. Thirteen percent of the cohort required maternal respiratory support for COVID-19 related hypoxia. Villous trophoblast necrosis was associated with maternal supplemental oxygen requirement (67 vs. 33%, p = 0.04) and intubation (67 vs. 33%, p = 0.01). CONCLUSION: In pregnancies complicated by COVID-19 disease, there was a high prevalence of placental histopathologic changes identified, particularly features of maternal vascular malperfusion, which could not be attributed solely to the presence of maternal-fetal comorbidities. The significantly increased prevalence of villous trophoblast necrosis in women needing respiratory support suggests a connection to the severity of COVID-19 illness.

Predictors and clinical outcomes of silent hypoxia in COVID-19 patients, a single-center retrospective cohort study.

BACKGROUND: Patients with COVID-19 usually present with fever and respiratory symptoms such as cough, sputum production, and dyspnea. However, they may suffer from severe hypoxemia without a clinical correlation with the respiratory symptoms, also known as silent or apathetic hypoxia. The aim of the study was to assess the predictors and clinical outcomes of COVID-19 patients without dyspnea. METHODS: A single-center retrospective cohort study, based on data extracted from the electronic hospital information system, with COVID-19 patients over a 10-month period in Riyadh, Saudi Arabia. RESULTS: Of the COVID-19 patients presenting at the Emergency Department with a SpO2 < 90%, 13% had silent hypoxia. The majority of the patients required BiPAP, 34% were intubated and 60% were admitted to an intensive care unit. There was no association between dyspnea and gender, age group, body mass index, or comorbidity. Cough, fever, and chronic cardiac diseases were predictive for dyspnea in a regression analysis. There was no difference in the clinical outcome between patients with silent dyspnea or dyspnea. Age and obesity were significantly associated with a decrease in survival, and an increase in the initial SpO2 increased survival. CONCLUSION: Patients with cardiac disease are more likely to present with silent hypoxia. The SpO2 saturation in COVID-19 may be an independent predictor of survival. Silent hypoxia in COVID-19 patients does not appear to have an association with increase in mortality.

Unmet need of essential treatments for critical illness in Malawi.

BACKGROUND: Critical illness is common throughout the world and has been the focus of a dramatic increase in attention during the COVID-19 pandemic. Severely deranged vital signs such as hypoxia, hypotension and low conscious level can identify critical illness. These vital signs are simple to check and treatments that aim to correct derangements are established, basic and low-cost. The aim of the study was to estimate the unmet need of such essential treatments for severely deranged vital signs in all adults admitted to hospitals in Malawi. METHODS: We conducted a point prevalence cross-sectional study of adult hospitalized patients in Malawi. All in-patients aged ≥18 on single days Queen Elizabeth Central Hospital (QECH) and Chiradzulu District Hospital (CDH) were screened. Patients with hypoxia (oxygen saturation <90%), hypotension (systolic blood pressure <90mmHg) and reduced conscious level (Glasgow Coma Scale <9) were included in the study. The a-priori defined essential treatments were oxygen therapy for hypoxia, intravenous fluid for hypotension and an action to protect the airway for reduced consciousness (placing the patient in the lateral position, insertion of an oro-pharyngeal airway or endo-tracheal tube or manual airway protection). RESULTS: Of the 1135 hospital in-patients screened, 45 (4.0%) had hypoxia, 103 (9.1%) had hypotension, and 17 (1.5%) had a reduced conscious level. Of those with hypoxia, 40 were not receiving oxygen (88.9%). Of those with hypotension, 94 were not receiving intravenous fluids (91.3%). Of those with a reduced conscious level, nine were not receiving an action to protect the airway (53.0%). CONCLUSION: There was a large unmet need of essential treatments for critical illness in two hospitals in Malawi.

Hypoxemia and Cytokine Storm in COVID-19: Clinical Implications.

One of the most dreadful complications that can occur during the course of COVID-19 is the cytokine storm-also known as cytokine release syndrome-a form of systemic inflammatory response syndrome triggered by SARS-CoV-2 infection. The cytokine storm is an activation cascade of auto-amplifying cytokines, which leads to excessive activation of immune cells and generation of pro-inflammatory cytokines. It occurs when large numbers of white blood cells are activated and release inflammatory cytokines, in turn activating even more white blood cells, finally resulting in an exaggerated pro-inflammatory-mediated response and ineffective anti-inflammatory control, leading to tissue damage, multiorgan failure, acute respiratory distress syndrome and death. Although cytokine storm pathogenesis is multifactorial, we hypothesize there is a close association between hypoxemia and cytokine storms in COVID-19, although it is difficult to establish the direction of this relationship. Most probably they coexist and, given enough time, one triggers the other in a chain reaction. Careful analysis of the day-to-day clinical evolution of COVID-19 indicates that there are short and slight periods of hypoxemia (confirmed by pulse oximetry and arterial gasometry), even on the day of the onset of persistent cough and/or shortness of breath. We propose the use of continuous positive airway pressure in early stages of COVID-19, at the onset of respiratory symptoms. This non-invasive ventilation method may be useful in individualized treatments to prevent early hypoxemia in COVID-19 patients and thus avoid triggering a cytokine storm. We believe such an approach is relevant everywhere, and in Cuba in particular, since the country has initiated national production of mechanical ventilation systems, including non-invasive ventilators. Moreover, as Cuba's COVID-19 protocols ensure early patient admission to isolation centers or hospitals, clinicians can prescribe the early use of continuous positive airway pressure as soon as respiratory symptoms begin, averting early hypoxemia and its triggering effect on cytokine storm development, and consequently, avoiding acute respiratory distress syndrome, multi-organ failure, and death.

Predictors of severe hypoxemia among COVID-19 patients in Burkina Faso (West Africa): Findings from hospital based cross-sectional study.

INTRODUCTION: COVID-19 is one of the world's major health crises. The objective of this study was to determine the predictive factors of severe hypoxemia in patients hospitalized in COVID-19 health facilities in Burkina Faso. PATIENTS AND METHOD: This study was a hospital-based cross-sectional study. The data collected relate to the period of the first wave of the epidemic (March 9 to June 30, 2020). All patients hospitalized for COVID-19 in the requisitioned health facilities of Ouagadougou were included in this study. Predictors of severe hypoxemia were identified using a multivariate logistic regression model. RESULTS: During the study period, 442 patients were included, representing 45.7% of the total number of positive patients in the entire country. The most common co-morbidities were diabetes (55; 12.4%) and arterial hypertension (97; 21.9%). Severe hypoxemia (SpO2 < 90%) was observed in 64 patients (14.5%). Age over 65 years (OR = 8.24; 95% CI: 2.83-24.01) and diabetes (OR = 2.43; 95% CI: 1.17-5.06) were the predictors for occurrence of severe hypoxemia in multivariate analysis. CONCLUSION: The predictive factors of COVID-19 are similar in African and Caucasian populations. The surveillance of COVID-19 in risk groups should be strengthened to reduce their morbidity and mortality.