Relation between lactate dehydrogenase levels and COVID-19 respiratory failure

Abstract

Early detection of severe patients with covid-19 is crucial for individual treatment. There is ample evidence that serum levels of lactate dehydrogenase (LDH) reflect the extent of various pathophysiological processes. However, current data on altered LDH dynamics in covid-19 pneumonia have not been well studied. Due to the small number of studies in patients with Covid-19, in this study, we decided to determine the relationship between LDH and PaO2 / FiO2 ratio to be able to use laboratory values of LDH as a predictor of the severity of pulmonary involvement in patients with Covid-19. Material and methods: The study was performed on 210 confirmed cases of covid-19 infection. Chest CT scan and PCR test were performed to confirm the presence of Covid-19 on patients. Serum LDH levels were determined on diagnostic examination and the relationship between LDH blood level and PaO2 / FiO2 ratio was measured as a marker of ARDS disease severity and pulmonary involvement as well as the relationship between LDH blood level and mortality in patients. Results: There was a significant difference in LDH levels between the groups with non-severe and severe respiratory failure (P <0.008). With increasing LDH, the amount of PO2 / FIO2 decreased and led to severe respiratory failure (r = -0.241 and P <0.0001) and LDH levels in deceased patients were much higher than in patients who have recovered (P <0.0001).