Vitamin C deficiency in critically ill COVID-19 patients admitted to intensive care unit.
Level 4 - case-series / case-control
Prospective single-center observational case series/cohort without a control group
PubMed 38188336 · doi:10.3389/fmed.2023.1301001
What was done
Prospective, observational, single-center study in an intensive care unit in Barcelona between November 2020 and February 2021. Plasma vitamin C concentrations were measured on days 1, 5, and 10 of admission in 43 patients with severe hypoxemic acute respiratory failure due to COVID-19 using ultra-performance liquid chromatography. Patients received standard care without enteral or parenteral vitamin C supplementation. Plasmatic levels were classified as undetectable (<1.5 mg/L), deficiency (<2 mg/L), low (2-5 mg/L), and normal (>5 mg/L).
What was found
Among 43 patients (65% men, mean age 62 ± 10 years, median SOFA score 3, median APACHE II score 13, 53% requiring invasive mechanical ventilation), 86% had undetectable plasma vitamin C levels on ICU admission. Low or undetectable levels remained constant throughout the 10-day study period in the vast majority of patients. Overall ICU and hospital survival were 77% and 74%, respectively.
Why it matters
It demonstrates that severe circulating vitamin C depletion is highly prevalent upon ICU admission and persistently sustained over the first 10 days in critically ill COVID-19 patients managed without supplementation.
Limits
Small, single-center observational sample (n = 43) lacking a non-COVID critically ill control group or healthy comparator group. Baseline pre-admission nutritional status was not assessed, and no therapeutic supplementation was tested to evaluate clinical outcomes.
Cited by
- supports Critically ill patients with conditions such as viral infections can have plasma vitamin C levels that are less than 25% of the levels observed in healthy individuals.