Can affinity of hemoglobin to oxygen to be a prognostic marker in critically ill COVID-19 patients?

Abstract

This study's objective is to determine the slope of the hemoglobin oxygen dissociation curve in critically ill patients who have COVID-19 along with blood gas measurements and how mortality might be impacted by this circumstance. It has been reported that the hemoglobin oxygen dissociation curve is not different from healthy patients in COVID-19. However, there are insufficient data on the behavior of the curve in patients who require intensive care. This retrospective study was conducted between 01.03.2021 and 01.07.2021 with patients who were followed up due to COVID-19 in adult intensive care unit. P50 and lactate value obtained from in vitro calculated blood gas analysis. The survival status of the patients was recorded. The mean P50 value at the admission of nonsurvivors was significantly higher than survivors. In correlation analysis, a significant positive correlation was seen between P50, mortality, and lactate level at admission. SpO2, PaO2/FiO2 ratio, and length of stay in intensive care unit were significantly negatively correlated with P50 levels. A right shift in the hemoglobin oxygen dissociation curve is associated with mortality. Lactate levels were also associated with a right shift. Prospective experimental studies are needed to provide a better understanding of this process.