Vitamin C administration shortened the length of stay in the intensive care unit on average by 8% in 12 trials with 1766 patients according to a meta-analysis published in Nutrients. The biochemistry of vitamin C is complex. For example, it is involved in the synthesis of norepinephrine and vasopressin, both of which influence the cardiovascular system, and carnitine, which is involved in energy metabolism.

Vitamin C levels can decline dramatically

However, through its epigenetic effects, vitamin C may influence hundreds of genes. In controlled trials, vitamin C has lowered blood pressure, decreased the incidence of atrial fibrillation; decreased bronchoconstriction, decreased pain, decreased glucose levels in patients with type 2 diabetes; and it has shortened the duration of colds. Very low vitamin C plasma levels are not uncommon in hospitals.

Furthermore, vitamin C metabolism; changed in many conditions; that involve physiological stress, such as infections, surgery, traumas, and burns; in which case vitamin C levels can decline dramatically. Although 0.1 grams per day of vitamin C can maintain a normal plasma level; in healthy persons, much higher doses; up to 4 grams per day, are needed for critically ill patients to increase their plasma vitamin C levels to the range of normal healthy people.

Therefore, high vitamin C doses may be needed to compensate for the increased metabolism in critically ill patients.Given that vitamin C has shown diverse effects on medical conditions, and the accumulated evidence for low vitamin C levels and increased metabolism of vitamin C in critically ill patients, vitamin C might influence practical outcomes such as the length of ICU stay, without any restrictions on the specific medical conditions that cause the stay in the ICU.

Vitamin C administration shortened ICU stay by 7.8%

Dr. Harri Hemilä from the University of Helsinki, Finland, and Dr. Elizabeth Chalker from the University of Sydney, Australia, carried out a systematic review of vitamin C for ICU patients. They identified 18 relevant controlled trials, and 12 of them; included in the meta-analysis on the length of stay. On average, vitamin C administration shortened ICU stay by 7.8%.
So in six trials, orally administered vitamin C with an average dose of 2 grams per day reduced the length; of ICU stay on average by 8.6%. According to Hemilä and Chalker, “Vitamin C is a safe, low-cost essential nutrient. Given the consistent evidence; from the trials published so far, vitamin C might administer to ICU patients; although further studies needed to find out optimal protocols for its administration. A few common cold studies have indicated that there may be a linear dose response for vitamin C on common cold duration for up to 6 and 8 grams per day. Evidently the dose response for doses higher than 2 grams per day should also be; investigated for ICU patients.”