Salma A. Rizo-Téllez, Immunometabolism Laboratory, Research Division, Hospital General de México “Dr. Eduardo Liceaga”; PECEM, Faculty of Medicine, National Autonomous University of Mexico; Mexico City, Mexico Alejandro Hernández-Solís, Pneumology and Thoracic Surgery Service, Hospital General de México ¨Dr. Eduardo Liceaga¨, Mexico City, Mexico Lucía A. Méndez-García, Immunometabolism Laboratory, Research Division, Hospital General de México “Dr. Eduardo Liceaga”, Mexico City, Mexico Galileo Escobedo, Immunometabolism Laboratory, Research Division, Hospital General de México “Dr. Eduardo Liceaga”, Mexico City, Mexico


Objective: Intensive care units (ICUs) collapsed under the global wave of coronavirus disease 2019 (COVID-19). Thus, we designed a clinical decision-making model that can help predict at hospital admission what patients with COVID-19 are at higher risk of requiring critical care. Methods: This was a cross-sectional study in 119 patients that met hospitalization criteria for COVID-19 including less than 30 breaths per minute, peripheral oxygen saturation < 93%, and/or ≥ 50% lung involvement on imaging. Depending on the need for critical care, patients were retrospectively assigned to ICU and non-ICU groups. Demographic, clinical, and laboratory parameters were collected at admission and analyzed by classification and regression tree (CRT). Results: Forty-five patients were admitted to ICU and 80% of them were men older than 57.13 ± 12.80 years on average. The leading comorbidity in ICU patients was hypertension. The CRT revealed that direct bilirubin (DB) > 0.315 mg/dl together with the neutrophil-to-monocyte ratio (NMR) > 15.90 predicted up to correctly in 92% of the patients the requirement of intensive care management, with sensitivity of 93.2%. Preexisting comorbidities did not influence on the tree growing. Conclusions: At hospital admission, DB and NMR can help identify nine in 10 patients with COVID-19 at higher risk of ICU admission.



Keywords: COVID-19. Severe acute respiratory syndrome coronavirus-2. Direct bilirubin. Neutrophil-to-monocyte ratio. Clinical decision-making model. Classification and regression trees.