Role of serum lactate to predict early clinical deterioration in hospitalized adult patients with severe acute respiratory syndrome coronavirus-2 infection: A retrospective study

Background: Hospitalized patients with severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection are at risk of further clinical deterioration and poor outcome. In this study, clinical risk factors of the requirement of mechanical ventilation within the first 24 h of hospital admission in coronavirus disease 2019 pneumonia patients have been evaluated.

Methods: In this retrospective study, admission characteristics of SARS-CoV-2-infected patients and risk factors for requiring mechanical ventilation and death within 24 h of admission have been evaluated. Predictive ability was evaluated by area under the receiver operating characteristic (AUROC) curve and independent association was checked by a logistic regression model.

Results: One hundred and forty-three subjects were recruited in this study and the median (interquartile range) age of the included subjects was 51 (40-60) years, and 68.5% (98 of 143) patients were male. Subjects who required mechanical ventilation in the first 24 h of admission had higher baseline respiratory rate (P < 0.0001), lower oxyhemoglobin saturation (P < 0.0001), higher serum lactate (P < 0.0001), and higher percentage of subjects complained of shortness of breath at the time of presentation (P = 0.005) and higher sequential organ function assessment (SOFA) score (P < 0.001). Serum lactate, baseline respiratory rate, and oxyhemoglobin saturation were predictors of the requirement of mechanical ventilation with an AUROC (95% confidence interval) of 0.80 (0.72-0.88), 0.75 (0.66-0.84), and 0.77 (0.68-0.86), respectively. Logistic regression revealed that a model reported that baseline serum lactate (P < 0.001) and SOFA score (P < 0.001) were independent predictors of mechanical ventilation within 24 h of intensive care unit admission.

Conclusion: Baseline serum lactate level predicts early requirement of mechanical ventilation in adult subjects with SARS-CoV-2 infection even after adjustment of disease severity parameters, SOFA score.