High-dose Intravenous Vitamin C (HDIVC) as Adjuvant Therapy in Critical Patients With Positive COVID-19. A Pilot Randomized Controlled Dose-comparison Trial.

Inclusion Criteria: * Adult patients with consent, adult men or women, age ≥ 18 years. * Laboratory confirmed SARS-CoV-2 infection as determined by polymerase chain reaction (PCR) or other commercial or public health assays; and/or clinical findings suggesting infection. * Hospitalized with a SARS-CoV-2 infection of any duration. * Ability to provide an informed consent signed by the study patient or a legally acceptable representative. * Willingness and ability to comply with the procedures/evaluations related to the study. * Have an oxygen saturation (SaO2) of 94% or less while breathing room air; or a ratio between the partial pressure of oxygen (PaO2) and the fraction of inspired oxygen (FiO2) (Pao2: Fio2) equal to or less than 300 mg. Hg. (WHO defines PAFI less than or equal to 250; being mild: 200-300; moderate: 100-200; severe: 100 or less. * Normal kidney function: (creatinine 0.7 mg / dl for men or 20 to 200ng / ml and 0.6 to 1.1 mg / dl for women or 15-150 ng / ml); urinary output greater than or equal to 1 cc / kg / hour; glomerular filtration rate greater than 30 cc / min). * Without chronic kidney disease (CKD) defined by stage II or higher according to the Kidney Disease Improving Global Outcomes (KDIGO) classification. Exclusion Criteria: * Age \<18 or pregnant or lactating woman. * Allergy to vitamin C. * Severe liver failure. * eGFR ≤ 30 ml / min / 1.73 m2 (defined by the CKD-EPI SCr formula). * History of any organ transplants requiring treatment active immunosuppressant that may interfere with kidney function. * If you required cardiopulmonary resuscitation (CPR) within 14 days, and/or DNR orders (do not resuscitate) DNI (do not intubate). * If death is considered imminent or unavoidable during this admission, and the treating physician, patient, or surrogate decision-maker is not engaged in active treatment. * Be on dialysis (either acute or chronic) or need dialysis imminent at the time of enrollment. * Patients with known HIV infection. * Patients with a known or suspected history of nephropathy due to oxalate or hyperoxaluria, scurvy, chronic iron overload, deficiency by G-6PD. * Patients with known hemochromatosis.