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.

Outcomes after Prolonged Weaning in Chronic Obstructive Pulmonary Disease Patients: Data from the German WeanNet Initiative.

BACKGROUND: The outcome of prolonged weaning in COPD patients is still unclear. METHODS: A subgroup analysis of 2,937 COPD patients (median: age 69 years, 5 comorbidities, 43% female) from the entire WeanNet cohort of specialized German weaning centers previously published (N = 11,424) was performed. RESULTS: Weaning outcomes were as follows: successful weaning without subsequent long-term noninvasive ventilation (NIV): N = 900; 30.6%; successful weaning with subsequent long-term NIV: N = 900; 30.6%; weaning failure with subsequent long-term invasive ventilation: N = 780; 26.6%; and death: N = 357; 12.2%. Most important predictors of mortality and weaning failure were advanced age and duration of mechanical ventilation in the transferring ICU, respectively. On discharge, the tracheostoma was closed in only 53% and 59% of patients with successful weaning not receiving and receiving long-term NIV, respectively. Unsuccessfully weaned patients were predominantly discharged home (20.5%) or to long-term care facilities (57.2%). Successfully weaned patients were predominantly discharged home (22.4%/35.9%: without/with NIV) and to rehabilitation (41.0%/43.1%: without/with NIV), respectively. CONCLUSION: COPD forms an important subgroup of prolonged weaning patients. Following transfer from the ICU to a specialized weaning center, weaning is successful more than 60%. Importantly, both tracheostomy status and initial destination following discharge are highly dependent on the weaning outcome.