Vitamin C (ascorbic acid) is a water-soluble vitamin with antioxidant properties.
Previous studies showed that the administration of vitamin C was associated with
decreased triglyceride (TG) levels in ambulatory patients, especially in patients with
type 2 diabetes. The decrease in TG level was more significant the younger the patient's
age (less than 52.8 years), the longer the administration of vitamin C lasted (over 12
weeks) and the higher the daily dose was (over 1 gram per day) (2). However, we did not
find any studies that examined the relationship between administration of vitamin C and
lowering of TG level in critical patients in intensive care. High TG levels are often
found in these patients, secondary to sepsis, administration of propofol by continuous
infusion, administration of TPN, pancreatitis, liver failure and chronic dyslipidemia,
diabetes and chronic renal failure. High TG levels in these patients may cause
pancreatitis secondary to elevated TG, and we take several actions to lower TG levels in
the unit when they exceed 500 mg per dL in order to avoid these complications. The
actions taken include starting treatment with fibrates and/or statins, giving high-dose
insulin, stopping the propofol drip and changing it to another hypnotic drug (usually
midazolam), and giving fat-free TPN instead of fat-containing TPN. There are of course
disadvantages to these interventions, such as drug interactions, longer clearance time
and higher incidence of delirium when giving midazolam compared to propofol, hypoglycemia
when giving a continuous insulin drip in high doses and giving a lower amount of calories
to a patient who will receive TPN without lipids.
There are many studies that examined the administration of vitamin C to patients in
intensive care, especially patients with sepsis, with varied but inconclusive results. A
recently published meta-analysis found a reduction in mortality among critical intensive
care patients treated with intravenous vitamin C, especially in the subgroup of
critically ill patients with a high risk of in-hospital mortality. The drug was found to
be safe for use among patients in intensive care. In these patients in the various
studies, vitamin C treatment was given intravenously in different doses, with most
patients receiving a dose of 6 grams per day for 3-5 days. In light of a trend about five
years ago that showed an improvement in survival among septic patients in intensive care
who were treated with intravenous vitamin C as monotherapy, or in combination with
steroids and/or intravenous thiamine, also in the intensive care unit at our institution
(as well as in other hospitals) we started giving this treatment, at the recommended dose
of 6 grams per day for 3-5 days. Over time, new studies did not find clear benefits for
this treatment, so we gradually stopped giving it. However, if indeed vitamin C can
contribute to a significant decrease in TG levels in patients in intensive care, there
may be a point in administering it to a group of patients with high TG levels, in order
to reduce complications associated with a high TG level and/or treatment to reduce it.