Introduction: The severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) infection resulted in significant worldwide morbidity and mortality. The aim of our study was to evaluate the results of laboratory tests performed on patients on admission to the hospital between groups of patients requiring and not requiring oxygen supplementation, and to find predictive laboratory indicators for the use of high-flow nasal oxygen therapy (HFNOT)/continuous positive airway pressure (CPAP)/bilevel positive airway pressure (BPAP). Materials and Methods: We retrospectively analysed the data of consecutive patients hospitalised in the Pulmonology Department of the Temporary COVID Hospital in Poznan from February to May 2021. On admission to the department, the patients had a panel of laboratory blood tests. Results: The study group consisted of 207 patients with a mean age of 59.2 ± 15.0 years of whom 179 (72%) were male. During hospitalisation, oxygen supplementation was required by 87% of patients. Patients requiring oxygen supplementation and/or the use of HFNOT/CPAP/BPAP had lower lymphocyte counts and higher levels of urea, C-reactive protein, D-dimer, troponin, glucose, lactate dehydrogenase (LDH) as well as higher white blood cell and neutrophil counts, The parameter that obtained the highest area under curve value in the receiver operator curve analysis for the necessary use of HFNOT/CPAP/BPAP or CPAP/BPAP was LDH activity. Conclusions: Among the basic parameters assessed on admission to the temporary hospital, LDH activity turned out to be the most useful for assessing the need for CPAP/BPAP active oxygen therapy. Other parameters that may be helpful for predicting the need for HFNOT/CPAP/BPAP are serum levels of urea, D-dimer and troponin.

Background: COVID-19 most often affects the respiratory system and may manifest as acute respiratory failure requiring the use of non-invasive respiratory support (NIRS). The aim of this study was to find predictors based on laboratory results and chest computed tomography (CT) scans performed on admission to the hospital indicating the need for NIRS and predicting mortality after hospital discharge. Methods: We retrospectively analysed data from consecutive patients hospitalised in the Pulmonology Department of the Temporary COVID Hospital in Poznan from 1 February 2021 to 31 March 2022. Upon admission to the department, the patients underwent a series of laboratory blood tests and high-resolution chest CT scan. Results: The study group included 282 patients, with an average age of 60.0 ± 15.0 years. In total, 54 (53%) patients of 101 requiring NIRS died from various causes or required intubation. Patients who required NIRS were significantly older and had more severe changes in the lung parenchyma. They had higher white blood cell and neutrophil counts and lower lymphocyte counts, as well as higher concentrations of D-dimer, CRP, PCT, and IL-6 and greater activities of LDH and AST. Conclusions: Laboratory tests and chest CT performed on hospital admission may be useful to rapidly identify patients at higher risk for severe disease.