Background: Critically ill patients are frequently suffering from vitamin C deficiency. Previous studies showed that high doses of vitamin C administration had conflicting results on clinical outcomes in patients with severe sepsis, burns and trauma. Because of high incidence and morbidity/mortality with severe pneumonia, we aimed to investigate the effect of administration of high dose vitamin C in critically ill patients with severe pneumonia.
Methods: Eighty critically ill patients with pneumonia were enrolled in this randomized double blinded clinical trial. Patients with CURB-65 score >3, one major criteria, or ≥3 minor criteria were considered as severe pneumonia. Patients were randomly assigned to intervention or placebo groups receiving standard treatment plus 60 mg/kg/day vitamin C as continuous infusion or normal saline in the same volume correspondingly for 96 hours. Serum levels of vitamin C were noted at baseline and 48 hours after vitamin C administration. Duration of mechanical ventilation, ICU length of stay, PaO2/FiO2 and mortality rate were noted for all patients till the 28th day. Any complications related to vitamin C administration were recorded. (IRCT registration number: IRCT20190312043030N1 , Registration date: 2019-08-26, seied hadi saghaleini).
Results: Duration of mechanical ventilation and vasopressor use were significantly lower in intervention group (p: <0.001 and 0.003, respectively). Baseline levels of vitamin C in both groups did not have significant difference but its levels increased in intervention group and decreased in control group during the study period. Mortality rate insignificantly decreased in intervention group (p: 0.17). Three patients showed hypotension and tachycardia during the administration of vitamin C which was self-limited with decreasing the dose of vitamin C.
Conclusion: Our results showed that the intravenous administration of a relatively high dose of vitamin C to critically ill patients with severe pneumonia was safe and could decrease the inflammation, mechanical ventilation duration and vasopressor use without any significant effect on mortality.