Abstract
Objective: SARS-CoV-2 has caused nearly 4 million confirmed
cases of COVID-19 worldwide in the approximately 4 months since it
emerged in Wuhan, China in December 2019. Comorbidities increase
morbidity and mortality in COVID-19, and many laboratory parameters have
been associated with mortality. The aim of the present study was to
identify the relationship between endogenous carboxyhemoglobin (COHb)
level and the clinical course and prognosis of COVID-19.
Methods: The study included 48 non-smokers or ex-smokers aged
18 years or older who presented to the emergency department, were
diagnosed with COVID-19 by real-time PCR analysis of nasopharyngeal swab
sample, and were treated in the pulmonary diseases ward of the Atatürk
University hospital after between March 24, 2020 and April 15, 2020. The
patients’ laboratory parameters and demographic data were analyzed
retrospectively.
Results : Prothrombin time and C-reactive protein (CRP),
troponin-I, and D-dimer levels decreased in COVID-19 patients during
follow-up (p=0.024, p=0.001, p=0.001, p=0.001), while
PaO2/FiO2 ratio and COHb increased
(p=0.002, p=0.001). COHb level at admission was significantly lower in
patients who developed macrophage activation syndrome (MAS), acute
respiratory distress syndrome (ARDS), and those who died compared to the
other patients (p=0.002, p=0.001). COHb level on day 5 of treatment was
significantly higher in patients with ARDS and patients who died
(p=0.001, p=0.001).Significant correlations were detected between COHb
level and CRP (r=-0.425, p=0.001), ferritin (r=-0.395, p=0.001) and
PaO2/FiO2 ratio (r=0.431, p=0.001).
Conclusions: COHb level may be an easily accessible biomarker
that guides early follow-up and treatment planning to avoid ARDS, MAS,
and mortality in COVID-19.
Keywords: COVID-19, endogenous carboxyhemoglobin, acute
respiratory distress