Mattia Busana1, Alessio Gasperetti2, Lorenzo Giosa3, Giovanni B Forleo4, Marco Schiavone4, Gianfranco Mitacchione5, Cecilia Bonino4, Paolo Villa4, Massimo Galli4, Claudio Tondo2, Ardan Saguner6, Peter Steiger6, Antonio Curnis5, Antonio Dello Russo7, Francesco Pugliese8, Massimo Mancone9, John J Marini10, Luciano Gattinoni11. 1. Department of Anesthesiology, Intensive Care and Emergency Medicine, Medical University of Göttingen, Göttingen, Germany - mat.busana@gmail.com. 2. Monzino Cardiology Center, IRCCS, Milan, Italy. 3. Department of Surgical Sciences, Città della Salute e della Scienza, Turin, Italy. 4. Luigi Sacco Hospital, Milan, Italy. 5. Spedali Civili Hospital, University of Brescia, Brescia, Italy. 6. University Hospital of Zurich, Zurich, Switzerland. 7. Clinic of Cardiology and Arithmology, Department of Biomedical Sciences and Public Health, Umberto I-Lancisi-Salesi University Hospital, Marche Polytechnic University, Ancona, Italy. 8. Department of General Surgery, Paride Stefanini Surgical Specialties, Sapienza University, Rome, Italy. 9. Department of Clinical Internal, Anesthesiological and Cardiovascular Sciences, Sapienza University, Rome, Italy. 10. Department of Pulmonary and Critical Care Medicine, University of Minnesota and Regions Hospital, Minneapolis, MN, USA. 11. Department of Anesthesiology, Intensive Care and Emergency Medicine, Medical University of Göttingen, Göttingen, Germany.
Abstract
BACKGROUND: In the early stages of COVID-19 pneumonia, hypoxemia has been described in absence of dyspnea ("silent" or "happy" hypoxemia). Our aim was to report its prevalence and outcome in a series of hypoxemic patients upon Emergency Department admission. METHODS: In this retrospective observational cohort study we enrolled a study population consisting of 213 COVID-19 patients with PaO<inf>2</inf>/FiO<inf>2</inf> ratio <300 mmHg at hospital admission. Two groups (silent and dyspneic hypoxemia) were defined. Symptoms, blood gas analysis, chest X-ray (CXR) severity, need for intensive care and outcome were recorded. RESULTS: Silent hypoxemic patients (68-31.9%) compared to the dyspneic hypoxemic patients (145-68.1%) showed greater frequency of extra respiratory symptoms (myalgia, diarrhea and nausea) and lower plasmatic LDH. PaO<inf>2</inf>/FiO<inf>2</inf> ratio was 225±68 mmHg and 192±78 mmHg in silent and dyspneic hypoxemia respectively (P=0.002). Eighteen percent of the patients with PaO<inf>2</inf>/FiO<inf>2</inf> from 50 to 150 mmHg presented silent hypoxemia. Silent and dyspneic hypoxemic patients had similar PaCO<inf>2</inf> (34.2±6.8 mmHg vs. 33.5±5.7 mmHg, P=0.47) but different respiratory rates (24.6±5.9 bpm vs. 28.6±11.3 bpm respectively, P=0.002). Even when CXR was severely abnormal, 25% of the population was silent hypoxemic. Twenty-six point five percent and 38.6% of silent and dyspneic patients were admitted to the ICU respectively (P=0.082). Mortality rate was 17.6% and 29.7% (log-rank P=0.083) in silent and dyspneic patients. CONCLUSIONS: Silent hypoxemia is remarkably present in COVID-19. The presence of dyspnea is associated with a more severe clinical condition.
BACKGROUND: In the early stages of COVID-19 pneumonia, hypoxemia has been described in absence of dyspnea ("silent" or "happy" hypoxemia). Our aim was to report its prevalence and outcome in a series of hypoxemic patients upon Emergency Department admission. METHODS: In this retrospective observational cohort study we enrolled a study population consisting of 213 COVID-19patients with PaO<inf>2</inf>/FiO<inf>2</inf> ratio <300 mmHg at hospital admission. Two groups (silent and dyspneic hypoxemia) were defined. Symptoms, blood gas analysis, chest X-ray (CXR) severity, need for intensive care and outcome were recorded. RESULTS: Silent hypoxemic patients (68-31.9%) compared to the dyspneic hypoxemic patients (145-68.1%) showed greater frequency of extra respiratory symptoms (myalgia, diarrhea and nausea) and lower plasmatic LDH. PaO<inf>2</inf>/FiO<inf>2</inf> ratio was 225±68 mmHg and 192±78 mmHg in silent and dyspneic hypoxemia respectively (P=0.002). Eighteen percent of the patients with PaO<inf>2</inf>/FiO<inf>2</inf> from 50 to 150 mmHg presented silent hypoxemia. Silent and dyspneic hypoxemic patients had similar PaCO<inf>2</inf> (34.2±6.8 mmHg vs. 33.5±5.7 mmHg, P=0.47) but different respiratory rates (24.6±5.9 bpm vs. 28.6±11.3 bpm respectively, P=0.002). Even when CXR was severely abnormal, 25% of the population was silent hypoxemic. Twenty-six point five percent and 38.6% of silent and dyspneic patients were admitted to the ICU respectively (P=0.082). Mortality rate was 17.6% and 29.7% (log-rank P=0.083) in silent and dyspneic patients. CONCLUSIONS:Silent hypoxemia is remarkably present in COVID-19. The presence of dyspnea is associated with a more severe clinical condition.
Authors: Tan Seng Beng; Carol Lai Cheng Kim; Chai Chee Shee; Diana Ng Leh Ching; Tan Jiunn Liang; Mehul Kumar Narendra Kumar; Ng Chong Guan; Lim Poh Khuen; Lam Chee Loong; Loh Ee Chin; Sheriza Izwa Zainuddin; David Paul Capelle; Ang Chui Munn; Lim Kah Yen; Nik Nathasha Hani Nik Isahak Journal: Am J Hosp Palliat Care Date: 2021-09-16 Impact factor: 2.090