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Sepsis/Septic Shock
Published in Charles Theisler, Adjuvant Medical Care, 2023
Ascorbic Acid: In one study, 14 patients with septic shock who required a vasopressor drug to maintain mean arterial pressure >65 mm Hg were assigned to receive either 25 mg/kg intravenous ascorbic acid every six hours or a matching placebofor 72 hours.4Administration of high-dose ascorbic acid significantly decreased the requirement for vasopressor's dose and duration in surgical critically ill patients with septic shock. Several mechanisms including anti-oxidant, anti-inflammatory, nitric oxide (NO) synthase inhibitory, reversing vascular hyporesponsiveness to vasopressors, increasing catecholamines and cortisol synthesis in adrenal medulla, and improving vascular endothelium integrity properties may justify the role of ascorbic acid in septic shock. In addition, no adverse event was detected in critically ill patients with burn injury who received ascorbic acid with a dose of 66 mg/kg/hour for 24 hours.4
Chemopreventive Agents
Published in David E. Thurston, Ilona Pysz, Chemistry and Pharmacology of Anticancer Drugs, 2021
Interestingly, there are some credible reports in the literature of laboratory experiments showing that ascorbic acid can reduce cell proliferation in vitro in several tumor cell lines including colon, prostate, hepatocellular, pancreatic, mesothelioma, and neuroblastoma. However, studies of ascorbic acid combined with other chemotherapy agents in animal models have provided mixed results, with improvement in efficacy and reduced side effects in some experiments but the reverse in others. Clinical trials in humans have shown that intravenous ascorbic acid is well tolerated, and the results of at least two studies of high-dose ascorbic in cancer patients have suggested an improved quality of life and a decrease in cancer-related side effects. However, there is no evidence to date to support the notion that ascorbic acid can act as a chemopreventive agent by blocking the damage of DNA and other cellular components by free radicals, one of the original hypotheses.
A “C Odyssey”
Published in Qi Chen, Margreet C.M. Vissers, Vitamin C, 2020
Mark Levine, Pierre-Christian Violet, Ifechukwude C. Ebenuwa, Hongbin Tu, Yaohui Wang
For ascorbic acid, specific pharmacokinetic goals were to learn how seven different ascorbic acid doses over an 80-fold range impacted steady-state blood and tissue concentrations in men and women, while simultaneously characterizing concentration relationships and normal physiology as extensively as possible [34,35]. Approaches were to conduct pharmacokinetic experiments in healthy humans, using oral and intravenous ascorbic acid. Data were obtained using a depletion-repletion design, with correction for all possible unintended vitamin and mineral deficiencies [36]. Subjects were hospitalized as inpatients at the National Institutes of Health (NIH) Clinical Research Center for approximately 6 months, to facilitate dietary control, compliance, and pharmacokinetic samplings over each of the seven different ascorbic acid doses. Subjects were first safely depleted of ascorbic acid using a vitamin C–restricted diet, with correction of any possible deficiencies in other vitamins [34–36]. When plasma concentrations were less than 10 μM, subjects were dose repleted in a stepwise manner. Subjects had to achieve steady state at each dose before advancing to the next highest dose. Daily doses were from 30 to 2500 mg. Half of the total daily dose was administered twice daily: before dinner, at least 4 hours after the past meal, or before breakfast in the morning, after overnight fasting. Ascorbic acid for oral administration was in a water solution, pH adjusted, with individualized doses that were routinely monitored for stability. Administration in this manner eliminated confounding effects of interferences from capsules or food components [37–39]. Ascorbic acid for intravenous injection was in individualized sterilized vials, pH adjusted, and routinely monitored for sterility and stability. The coulometric HPLC electrochemical measurement technique described earlier was utilized so that ascorbic acid could be measured in clinical samples. Measurements provided necessary sensitivity and specificity, without interferences from compounds in biological samples, and sample stability was accounted for during sample processing, assay, and long-term storage [21,40].
Advancements in the pharmacological management of sepsis in the elderly
Published in Expert Opinion on Pharmacotherapy, 2023
Christos Psarrakis, Evangelos J. Giamarellos-Bourboulis
In the ORANGES trial the findings were partially contradictive. This was a double-blind RCT and 137 patients in ICU with sepsis or septic shock (mean age 65 years) were randomized to receive either intravenous ascorbic acid 1500 mg, hydrocortisone 50 mg every 6 hours and thiamine 200 mg every 12 hours or placebo for a maximum of 4 days. The study showed that triple therapy compared to placebo was associated with higher rates of shock reversal defined as stop of vasopressor support (p < 0.001). However, no difference between the two study groups was reported for the baseline change of SOFA score at day 4 (−2.9 points in the intervention group vs −.93 in the placebo group), in-hospital-mortality (16.4% vs 19%, OR: 1.25, 95% CI: 0.5–2.97, p = 0.65) or length of hospital stay (mean 11.5 days vs 11 days, p = 0.75) [89].
Effect of hematocrit, galactose and ascorbic acid on the blood glucose readings of three point-of-care glucometers
Published in Scandinavian Journal of Clinical and Laboratory Investigation, 2022
Fawaz Albloui, James John, Osama Alghamdi, Faisal Alseraye, Abdullah Alqahtani, Waleed Tamimi, Abdullah Albloshi, Fahad M. Aldakheel, Ayesha Mateen, Rabbani Syed
Intravenous administration of ascorbic acid (6 g/d) in combination with thiamine and hydrocortisone was found to improve the outcome of critically ill patients with sepsis and reduced the mortality rate [26]. Additionally, intravenous ascorbic acid could be beneficial for COVID-19 patients with acute respiratory distress syndrome [27,28]. However, such electrochemical substances present in the blood could affect the reliability of POCGs that use electrical signals for glucose measurement. Several studies reported that POCGs were affected by the presence of ascorbic acid [10,17]. In this study, the Freestyle and ACCU-Chek Inform II glucose results were affected when ascorbic acid concentration was added.