Mortality in septic patients treated with vitamin C: a systematic meta-analysis

The effects of antioxidant supplementation on short-term mortality in sepsis patients

Background

The occurrence and development of sepsis are related to the excessive production of oxygen free radicals and the weakened natural clearance mechanism. Further dependable evidence is required to clarify the effectiveness of antioxidant therapy, especially its impact on short-term mortality.

Objectives

The purpose of this systematic review and meta-analysis was to evaluate the effect of common antioxidant therapy on short-term mortality in patients with sepsis.

Methods

According to PRISMA guidelines, a systematic literature search on antioxidants in adults sepsis patients was performed on PubMed/Medline, Embase, and the Cochrane Library from the establishment of the database to November 2023. Antioxidant supplements can be a single-drug or multi-drug combination: HAT (hydrocortisone, ascorbic acid, and thiamine), ascorbic acid, thiamine, N-acetylcysteine and selenium. The primary outcome was the effect of antioxidant treatment on short-term mortality, which included 28-day mortality, in-hospital mortality, intensive care unit mortality, and 30-day mortality. Subgroup analyses of short-term mortality were used to reduce statistical heterogeneity and publication bias.

Results

Sixty studies of 130,986 sepsis patients fulfilled the predefined criteria and were quantified and meta-analyzed. Antioxidant therapy reduces the risk of short-term death in sepsis patients by multivariate meta-analysis of current data, including a reduction of in-hospital mortality (OR = 0.81, 95% CI 0.67 to 0.99; P = 0.040) and 28-day mortality (OR = 0.81, 95% CI 0.69 to 0.95]; P = 0.008). Particularly in subgroup analyses, ascorbic acid treatment can reduce in-hospital mortality (OR = 0.66, 95% CI 0.90 to 0.98; P = 0.006) and 28-day mortality (OR = 0.43, 95% CI 0.24 to 0.75; P = 0.003). However, the meta-analysis of RCTs found that antioxidant therapy drugs, especially ascorbic acid, did substantially reduce short-term mortality(OR = 0.78, 95% CI 0.62 to 0.98; P = 0.030; OR = 0.57, 95% CI 0.36 to 0.91; P = 0.020).

Conclusions

According to current data of RCTs, antioxidant therapy, especially ascorbic acid, has a trend of improving short-term mortality in patients with sepsis, but the evidence remains to be further demonstrated.

High-dose Vitamin C injection ameliorates against sepsis-induced myocardial injury by anti-apoptosis, anti-inflammatory and pro-autophagy through regulating MAPK, NF-κB and PI3K/AKT/mTOR signaling pathways in rats

AIMS

This study aimed to evaluate the effects of VC on SIMI in rats.

METHODS

In this study, the survival rate of high dose VC for SIMI was evaluated within 7 days. Rats were randomly assigned to three groups: Sham group, CLP group, and high dose VC (500 mg/kg i.v.) group. The animals in each group were treated with drugs for 1 day, 3 days or 5 days, respectively. Echocardiography, myocardial enzymes and HE were used to detect cardiac function. IL-1β, IL-6, IL-10 and TNF-α) in serum were measured using ELISA kits. Western blot was used to detect proteins related to apoptosis, inflammation, autophagy, MAPK, NF-κB and PI3K/Akt/mTOR signaling pathways.

RESULTS

High dose VC improved the survival rate of SIMI within 7 days. Echocardiography, HE staining and myocardial enzymes showed that high-dose VC relieved SIMI in rats in a time-dependent manner. And compared with CLP group, high-dose VC decreased the expressions of pro-apoptotic proteins, while increased the expression of anti-apoptotic protein. And compared with CLP group, high dose VC decreased phosphorylation levels of Erk1/2, P38, JNK, NF-κB and IKK α/β in SIMI rats. High dose VC increased the expression of the protein Beclin-1 and LC3-II/LC3-I ratio, whereas decreased the expression of P62 in SIMI rats. Finally, high dose VC attenuated phosphorylation of PI3K, AKT and mTOR compared with the CLP group.

SIGNIFICANCE

Our results showed that high dose VC has a good protective effect on SIMI after continuous treatment, which may be mediated by inhibiting apoptosis and inflammatory, and promoting autophagy through regulating MAPK, NF-κB and PI3K/AKT/mTOR pathway.

High-dose vitamin C improves norepinephrine level in patients with septic shock: A single-center, prospective, randomized controlled trial

BACKGROUND

The effects of vitamin C supplementation on patients with septic shock remain controversial. We aimed to evaluate the effects of different vitamin C dosages on norepinephrine (NE) synthesis in adult patients with septic shock.

METHODS

A total of 58 patients with septic shock admitted to our intensive care unit (ICU) between July 2021 and December 2022 were included. Patients were randomly divided into 3 groups: high-dose vitamin C (150 mg/kg/d, group A), low-dose vitamin C (50 mg/kg/d, group B), and placebo (group C). NE synthesis-related indicators (dopamine-β-hydroxylase [DβH], tyrosine hydroxylase [TH], tetrahydrobiopterin [BH4], and dopamine [DA]), plasma NE, and vitamin C levels were measured every 24 hours and analyzed. All-cause mortality within 28 days and other clinical outcomes (including Acute Physiology and Chronic Health Evaluation [APACHE], Sequential Organ Failure Assessment [SOFA], and Multiple-Organ Dysfunction Syndrome [MODS] scores) were compared.

RESULTS

Changes in TH, BH4, and DβH levels at 96 hours in groups A and B were greater than those in group C. These differences became more pronounced over the course of the intravenous vitamin C administration. Significant differences between groups A and C were detected at 96-hours TH, 72-hours BH4, 96-hours BH4, 96-hours DA, and DβH levels every 24 hours. The 96-hours TH, 96-hours BH4, and 48-hours DβH in group B were significantly higher than those in group C. The NE levels every 24 hours in groups A and B were higher than those in group C, group A and group C had a statistically significant difference. The 96-hours exogenous NE dosage in groups A and B was significantly lower than that in group C. No significant reductions in APACHE, SOFA, or MODS scores were observed in the vitamin C group, including the duration of ICU stay and mechanical ventilation. The 28-days mortality was lower in groups A and B than in group C (0%, 10%, and 16.67%, P = .187), but the difference was not significant.

CONCLUSION

For patients with septic shock, treatment with vitamin C significantly increased TH, BH4, and DβH levels and reduced the exogenous NE dosage, but did not significantly improve clinical outcomes.

Intravenous high-dose vitamin C monotherapy for sepsis and septic shock: A meta-analysis of randomized controlled trials

BACKGROUND

Vitamin C has been used as an adjuvant in the treatment of sepsis and septic shock; however, its role remains controversial. This study aimed to assess the effectiveness of intravenous high-dose vitamin C in sepsis and septic shock patients by meta-analysis.

METHODS

The PubMed, Embase, and Cochrane Library electronic databases were searched to identify relevant studies. The primary outcome was defined as the short-term all-cause mortality rate. Secondary outcomes included duration of vasoactive drug use, intensive care unit length of stay, sequential organ failure assessment scores up to 96 hours after treatment and 90-day mortality. Review Manager version 5.4 was used to perform the meta-analysis. Relative risk and mean differences (MD) with 95% confidence intervals were determined using fixed- or random-effects models.

RESULTS

Eight randomized controlled trials (RCTs) comprising 1394 patients were eligible for assessment. Overall, the pooled results showed that high-dose vitamin C decreased short-term all-cause mortality in patients with sepsis, but no significant differences were observed in patients with septic shock. Additionally, high-dose vitamin C was associated with decreased duration of vasoactive drug use in patients with sepsis, but not in patients with septic shock. However, it did not significantly affect the duration of intensive care unit stay in RCTs of patients with sepsis and septic shock. Additionally, it did not significantly affect sequential organ failure assessment scores 96 hours post-treatment or 90-day mortality.

CONCLUSION

These results suggest that intravenous high-dose vitamin C may improve outcomes in patients with sepsis, but do not benefit patients with septic shock. Further RCTs and other studies should be conducted to determine whether vitamin C should be recommended as an adjunctive sepsis treatment.

Real-time monitoring of vitamin C levels in trauma patients by electron-spin resonance spectrometry

BACKGROUND

In critically ill patients, healthy vitamin C levels are important to avoid an imbalance in reactive oxygen species. To achieve this, oxidative stress levels in emergency patients need to be accurately measured in real-time. However, normally, reactive oxygen/nitrogen species are short-lived, rendering measurement difficult; moreover, measurement of relatively stable antioxidants and other oxidative stress markers in real-time is challenging. Therefore, we used electron-spin resonance spectrometry (ESR) to assess vitamin C levels, clarify their relationship with patients' severity, and establish more effective vitamin C therapy in critically ill patients.

METHODS

We studied 103 severely ill emergency patients and 15 healthy volunteers. Vitamin C radical (VCR/dimethyl sulfoxide [DMSO]) values were analyzed in arterial blood samples by ESR at admission and once daily thereafter during the acute recovery phase. Severity scores were calculated. The relationship between these scores and VCR/DMSO values and chronological changes in VCR/DMSO values were analyzed.

RESULTS

Serum VCR/DMSO values were significantly lower in critically ill patients than in healthy volunteers (0.264 ± 0.014 vs. 0.935 ± 0.052, p < 0.05), particularly in the severe trauma group and the cardiopulmonary arrest/post-cardiac arrest syndrome group. VCR/DMSO values and various severity scores did not correlate at admission; however, they correlated with SOFA scores from days 2-6. VCR/DMSO values remained low from the first measurement day through Day 6 of illness.

CONCLUSIONS

Vitamin C levels were low at admission, remained low with conventional nutritional support, and did not correlate with the initial patient's severity; however, they correlated with patients' severity after admission. Some patients had normal vitamin C levels. Therefore, vitamin C levels should be measured in real-time and supplemented if they are below normal levels.

TRIAL REGISTRATION

Retrospectively registered.

Effect of intravenous vitamin C on adult septic patients: a systematic review and meta-analysis

Background

An increasing number of studies indicate that vitamin C (VC) reduces the mortality of adult septic patients, while some articles suggest otherwise. We performed this systematic review and meta-analysis to resolve the discrepancies in reported results concerning the efficacy of VC in septic patients.

Methods

We comprehensively searched MEDLINE, EMBASE, and the Cochrane Central Register of Controlled trials for randomized controlled trials (RCTs) evaluating the efficacy of intravenous VC (IVVC) on adult septic patients published from inception to November 28, 2022. The quality of outcomes for eligible studies was assessed using the Recommendations Assessment, Development, and Evaluation methodology. The results were analyzed using the pooled mean difference (MD) or risk ratio (RR) and 95% confidence intervals (CIs).

Results

Twenty-two studies (3,570 adult septic patients) were included. IVVC treatment did not improve 28-day mortality compared to the control group (RR, 0.92; 95% CI, 0.81-1.04; I2 = 26%; evidence risk, moderate). IVVC monotherapy decreased mortality (RR, 0.69; 95% CI, 0.52-0.93; I2 = 57%), whereas combination therapy did not affect mortality (RR, 1.03; 95% CI, 0.90-1.17; I2 =0%). IVVC had a trend to decrease the mortality of septic patients (RR, 0.83; 95% CI, 0.69-1.00; I2 = 33%) but did not affect septic shock patients (RR, 1.01; 95% CI, 0.85-1.21; I2 = 18%). IVVC reduced the duration of vasopressor use (MD, -8.45; 95% CI, -15.43 to -1.47; evidence risk, very low) but did not influence the incidence of AKI, ICU length of stay, duration of mechanical ventilation.

Conclusions

IVVC treatment did not improve the 28-day mortality in septic patients. Subgroup analysis indicated that VC had a trend to decrease the 28-day mortality in patients with sepsis but not septic shock. IVVC monotherapy, rather than combination therapy, decreased the 28-day mortality in septic patients. The findings imply that Hydrocortisone, Ascorbic acid, Thiamine (HAT) combination therapy is not superior to IVVC monotherapy for septic patients. These findings warrant further confirmation in future studies, which should also investigate the mechanisms underlying the enhanced efficacy of IVVC monotherapy in septic patients.

Systematic review registration

https://inplasy.com/.

The Best Surgical Treatment for Cervical Radiculopathy: A Systematic Review and Network Meta-Analysis

A case with an inflamed or damaged nerve root in the cervical spine is defined as cervical radiculopathy.The purpose of the current study is to recognize the most effective surgical procedures in cervical radiculopathy subjects. All related studies were taken using PubMed searching international databases, Scopus, ISI Web of Science (WoS), and Science direct with no limit of until November 20th, 2021. Finally, based on the inclusion and exclusion criteria, after reviewing all randomized controlled trial studies which had the related data the researchers were looking for, they conducted meta-analysis with the seven remaining studies including eight different treatments. Heterogeneity was evaluated by Cochran's Q and Higgins I2 using R software for the network. In the results presented in this study, the neck disability index (NDI) changes as a result of taking cervical anterior discectomy without (ACD) and with fusion (ACDF) and ACD arthroplasty were -0.003, -1.659, and -1.656, respectively. According to the final diagram of the network, 11 comparisons were made in pairs. When each treatment group is compared with ACDF, it is shown that there was a significant mean effect among the patients who receive Mobi-C, Kineflx|C, and ADR, with mean differences of - 8.60 [CI 95% (- 12.75, - 4.45)], - 1.10 [CI 95% (- 5.22, 3.02)], and - 1.00 [CI 95% (- 7.18, 5.18)], respectively. The most effective surgical treatments for cervical radiculopathy were Mobi-c, Kineflx|C, and artificial disc replacement compared to ACDF treatment, respectively.

Exploring hub pyroptosis-related genes, molecular subtypes, and potential drugs in ankylosing spondylitis by comprehensive bioinformatics analysis and molecular docking

BACKGROUND

Ankylosing spondylitis (AS) is a chronic inflammatory autoimmune disease, and the diagnosis and treatment of AS have been limited because its pathogenesis is still unclear. Pyroptosis is a proinflammatory type of cell death that plays an important role in the immune system. However, the relationship between pyroptosis genes and AS has never been elucidated.

METHODS

GSE73754, GSE25101, and GSE221786 datasets were collected from the Gene Expression Omnibus (GEO) database. Differentially expressed pyroptosis-related genes (DE-PRGs) were identified by R software. Machine learning and PPI networks were used to screen key genes to construct a diagnostic model of AS. AS patients were clustered into different pyroptosis subtypes according to DE-PRGs using consensus cluster analysis and validated using principal component analysis (PCA). WGCNA was used for screening hub gene modules between two subtypes. Gene Ontology (GO) terms and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways were used for enrichment analysis to elucidate underlying mechanisms. The ESTIMATE and CIBERSORT algorithms were used to reveal immune signatures. The connectivity map (CMAP) database was used to predict potential drugs for the treatment of AS. Molecular docking was used to calculate the binding affinity between potential drugs and the hub gene.

RESULTS

Sixteen DE-PRGs were detected in AS compared to healthy controls, and some of these genes showed a significant correlation with immune cells such as neutrophils, CD8 + T cells, and resting NK cells. Enrichment analysis showed that DE-PRGs were mainly related to pyroptosis, IL-1β, and TNF signaling pathways. The key genes (TNF, NLRC4, and GZMB) screened by machine learning and the protein-protein interaction (PPI) network were used to establish the diagnostic model of AS. ROC analysis showed that the diagnostic model had good diagnostic properties in GSE73754 (AUC: 0.881), GSE25101 (AUC: 0.797), and GSE221786 (AUC: 0.713). Using 16 DE-PRGs, AS patients were divided into C1 and C2 subtypes, and these two subtypes showed significant differences in immune infiltration. A key gene module was identified from the two subtypes using WGCNA, and enrichment analysis suggested that the module was mainly related to immune function. Three potential drugs, including ascorbic acid, RO 90-7501, and celastrol, were selected based on CMAP analysis. Cytoscape showed GZMB as the highest-scoring hub gene. Finally, molecular docking results showed that GZMB and ascorbic acid formed three hydrogen bonds, including ARG-41, LYS-40, and HIS-57 (affinity: -5.3 kcal/mol). GZMB and RO-90-7501 formed one hydrogen bond, including CYS-136 (affinity: -8.8 kcal/mol). GZMB and celastrol formed three hydrogen bonds, including TYR-94, HIS-57, and LYS-40 (affinity: -9.4 kcal/mol).

CONCLUSIONS

Our research systematically analyzed the relationship between pyroptosis and AS. Pyroptosis may play an essential role in the immune microenvironment of AS. Our findings will contribute to a further understanding of the pathogenesis of AS.

[Immunomodulation by nutritional intervention in critically ill patients]

Critically ill patients often suffer from a complex and severe immunological dysfunction. The differentiation and function of human immune cells are fundamentally controlled through metabolic processes. New concepts of immunonutrition therefore try to use enteral and parenteral nutrition to positively impact on the immune function of intensive care unit patients. This review article concisely presents the currently available evidence on the commonly used isolated supplements (anti-oxidative substances, amino acids, essential fatty acids) and difficulties related to their clinical use. The second part presents new and more comprehensive concepts of immunonutrition to influence the intestinal microbiome and to modulate the macronutrient composition. Immunonutrition of critically ill patients bears enormous potential and could become a valuable clinical tool for modulation of the immunometabolism of intensive care unit patients.

Impact of intravenous vitamin C as a monotherapy on mortality risk in critically ill patients: A meta-analysis of randomized controlled trials with trial sequential analysis

Background

This meta-analysis aimed at investigating the pooled evidence regarding the effects of intravenous vitamin C (IVVC) on mortality rate in critically ill patients.

Methods

Databases including Medline, Embase, and Cochrane Library were searched from inception to October, 2022 to identify RCTs. The primary outcome was the risk of overall mortality. Subgroup analyses were performed based on IVVC dosage (i.e., cut-off value: 100 mg/kg/day or 10000 mg/day). Trial sequential analysis (TSA) was used to examine the robustness of evidence.

Results

A total of 12 trials including 1,712 patients were analyzed. Although meta-analysis demonstrated a lower risk of mortality in patients with IVVC treatment compared to those without [risk ratio (RR): 0.76, 95% CI: 0.6 to 0.97, p = 0.02, I2 = 36%, 1,711 patients), TSA suggested the need for more studies for verification. Moreover, subgroup analyses revealed a reduced mortality risk associated with a low IVVC dosage (RR = 0.72, p = 0.03, 546 patients), while no beneficial effect was noted with high IVVC dosage (RR = 0.74, p = 0.13, I2 = 60%, 1,165 patients). The durations of vasopressor [mean difference (MD): −37.75 h, 404 patients) and mechanical ventilation (MD: −47.29 h, 388 patients) use were shorter in the IVVC group than those in the controls, while there was no significant difference in other prognostic outcomes (e.g., length of stay in intensive care unit/hospital) between the two groups.

Conclusion

Although intravenous vitamin C as a monotherapy reduced pooled mortality, durations of vasopressor use and mechanical ventilation, further research is required to support our findings and to identify the optimal dosage of vitamin C in the critical care setting.

Systematic review registration

https://www.crd.york.ac.uk/prospero/, identifier CRD42022371090.

Effects of hydrocortisone combined with vitamin C and vitamin B1 versus hydrocortisone alone on microcirculation in septic shock patients: A pilot study

OBJECTIVE

To investigate the effects of hydrocortisone combined with vitamin C and vitamin B1 versus hydrocortisone on sublingual microcirculation in septic shock patients.

METHODS

This pilot study enrolled septic shock patients admitted to the ICU of a tertiary teaching hospital from February 2019 to January 2020. We randomly assigned the enrolled patients to the treatment group (hydrocortisone combined with vitamin C and vitamin B1 added to standard care) and the control group (hydrocortisone alone added to standard care) in a 1 : 1 ratio. The primary outcome was perfused small vascular density (sPVD) monitored by a sublingual microcirculation imaging system at 24 hours after treatment.

RESULTS

Twelve patients in the treatment group and ten in the control group completed the study. The baseline characteristics were comparable between the groups. No statistically significant difference was found in the sPVD between the groups at baseline. The sPVD in the treatment group was significantly higher than that in the control group at 4 hours after treatment (mean difference, 7.042; 95% CI, 2.227-11.857; P = 0.009) and 24 hours after treatment (mean difference, 7.075; 95% CI, 2.390-11.759; P = 0.008).

CONCLUSIONS

Compared with hydrocortisone, hydrocortisone combined with vitamin C and vitamin B1 significantly improves microcirculation in septic shock patients.

A Systematic Review and Meta-Analysis on Possible Role of Vitamin C in Sepsis

Sepsis is a substantial healthcare burden, and its management continues to be a major challenge. Prior studies demonstrate conflicting evidence regarding the utility of vitamin C in sepsis. This systematic review and meta-analysis aim to collect data among critically ill patients (sepsis/septic shock), comparing the efficacy of parenteral vitamin C with standard care. A literature review was conducted using databases including PubMed, Web of Science, Google Scholar, and the Cochrane Library to identify randomized controlled trials (RCTs) and observational studies comparing intravenous vitamin C alone or in combination with thiamine or glucocorticoids to the standard of care. We identified 11 RCTs and seven retrospective cohort studies. The primary outcome was 28-day mortality. Secondary outcomes included intensive care unit (ICU) length of stay, change in Sequential Organ Failure Assessment (SOFA) score, duration of vasopressor use, and duration of mechanical ventilation. A total of 18 studies with 4078 patients were included in our final analysis. Overall, we found no mortality reduction in patients treated with vitamin C compared to standard of care (odds ratio (OR) 0.92; 95% confidence interval (CI) 0.78 to 1.09; p = 0.34). Studies that reported a change in SOFA scores, ICU length of stay, duration of mechanical ventilation, or duration of vasopressor use did not show any significant difference between groups. Subgroup analysis with RCT versus observational studies and vitamin C dosage regimens did not show any difference. Among patients with sepsis or septic shock, treatment with vitamin C was not associated with a reduction in mortality, ICU length of stay, change in SOFA score, duration of vasopressor use, or duration of mechanical ventilation. Further studies are needed to demonstrate the potential role of vitamin C in the management of sepsis.

Current role of high dose vitamin C in sepsis management: A concise review

Sepsis and septic shock are common diagnoses for patients requiring intensive care unit admission and associated with high morbidity and mortality. In addition to aggressive fluid resuscitation and antibiotic therapy, several other drugs have been tried as adjuvant therapies to reduce the inflammatory response and improve outcomes. Vitamin C has been shown to have several biological actions, including anti-inflammatory and immunomodulatory effects, which may prove beneficial in sepsis management. Initial trials showed improved patient outcomes when high dose vitamin C was used in combination with thiamine and hydrocortisone. These results, along with relative safety of high-dose (supra-physiological) vitamin C, encouraged physicians across the globe to add vitamin C as an adjuvant therapy in the management of sepsis. However, subsequent large-scale randomised control trials could not replicate these results, leaving the world divided regarding the role of vitamin C in sepsis management. Here, we discuss the rationale, safety profile, and the current clinical evidence for the use of high-dose vitamin C in the management of sepsis and septic shock.

Early ascorbic acid administration prevents vascular endothelial cell damage in septic mice

Oxidation of BH₄, a cofactor of nitric oxide synthase (NOS), produces reactive oxygen species (ROS) through uncoupling of NOS and affects vascular endothelial dysfunction. Ascorbic acid (AsA) inhibits the oxidation of BH₄ and reduces ROS. However, the kinetic changes of BH₄ in sepsis and its effect on the kinetic changes in AsA administration therapy, as well as the appropriate timing of AsA administration for AsA therapy to be effective, are unclear. Mice with sepsis, induced by cecal ligation and puncture (CLP), were examined for the effect of AsA administration (200 mg/kg) on vascular endothelial cell dysfunction at two administration timings: early group (AsA administered immediately after CLP) and late group (AsA administered 12 h after CLP). Survival rates were compared between the early and late administration groups, and vascular endothelial cell damage, indicated by the dihydrobiopterin/tetrahydrobiopterin ratio, serum syndecan-1, and endothelial nitric oxide synthase, as well as liver damage, were examined. The early group showed significantly improved survival compared to the non-treatment group (p < 0.05), while the late group showed no improved survival compared to the non-treatment group. Compared to the non-treated group, the early AsA group showed less oxidation of BH₄ in sepsis. Syndecan1, a marker of vascular endothelial cell damage, was less elevated and organ damage was reduced in the early AsA-treated group. In septic mice, early AsA administration immediately after CLP may protect vascular endothelial cells by inhibiting BH₄ oxidation, thereby reducing organ dysfunction and improving survival.

Parenteral Vitamin C in Patients with Severe Infection: A Systematic Review

BACKGROUND: Inflammation and oxidative damage caused by severe infections may be attenuated by vitamin C. METHODS: We conducted a systematic review of randomized controlled trials (RCTs) of parenteral vitamin C as combined therapy or monotherapy versus no parenteral vitamin C administered to adults hospitalized with severe infection. The primary outcome was mortality. We performed random-effects meta-analyses and assessed certainty in effect estimates. RESULTS: Of 1547 citations, 41 RCTs (n = 4915 patients) were eligible for inclusion. Low-certainty evidence suggested that vitamin C may reduce in-hospital mortality (21 RCTs, 2762 patients; risk ratio, 0.88 [95% confidence interval (CI), 0.73 to 1.06]), 30-day mortality (24 RCTs, 3436 patients; risk ratio, 0.83 [95% CI, 0.71 to 0.98]), and early mortality (before hospital discharge or 30 days; 34 RCTs, 4366 patients; risk ratio, 0.80 [95% CI, 0.68 to 0.93]). Effects were attenuated in sensitivity analyses limited to published blinded trials at low risk-of-bias (in-hospital mortality: risk ratio, 1.07 [95% CI, 0.92 to 1.24], moderate certainty; 30-day mortality: risk ratio, 0.88 [95% CI, 0.71 to 1.10], low certainty; and early mortality: risk ratio, 0.88 [95% CI, 0.73 to 1.06], low certainty). For 90-day mortality, all trials had low risk-of-bias; moderate-certainty evidence suggested harm (five RCTs, 1722 patients; risk ratio, 1.07 [95% CI, 0.94 to 1.21]). Moderate-certainty evidence suggested an increased risk of hypoglycemia (risk ratio, 1.20 [95% CI, 0.69 to 2.08]). Effects on other secondary outcomes were mixed and informed by low-certainty evidence. No credible subgroup effects were observed for mortality related to cointerventions (monotherapy vs. combined therapy), dose, or type of infection (Covid-19 vs. other). CONCLUSIONS: Overall, evidence from RCTs does not establish a survival benefit for vitamin C in patients with severe infection. (PROSPERO number, CRD42020209187.)

Delayed Diagnosis of Severe Hypoglycemia in a Septic Patient With Chronic Renal Failure

High-dose vitamin C therapy has gained increased interest as an adjunctive treatment of septic shock, although convincing evidence is still lacking. High blood levels of vitamin C may interfere with several point-of-care blood glucose meters. We describe the case of a 67-year-old septic patient known with chronic renal failure who developed truly severe hypoglycemia, which was masked by spuriously high glucose values measured on a capillary blood glucose meter. This initially led to the treatment of spurious hyperglycemia with high-dose insulin and a delayed correct diagnosis and treatment, rendering substantial risk for the patient. Awareness of this dangerous interference is warranted.

The Role and Efficacy of Vitamin C in Sepsis: A Systematic Review and Meta-Analysis

Clinical rationale for study: Despite advancements in critical care, the mortality rate of sepsis remains high, with an overall poor prognosis. There is a complex pathophysiology of a lethal cascade of cytokines and inflammatory proteins underlying sepsis. The use of vitamin C can theoretically suppress the inflammatory cascade but remains a questionable practice due to a lack of conclusive evidence. Aims of the study: To appraise the therapeutic role of vitamin C in sepsis. Materials and methods: A systematic review was conducted on PubMed, Embase, and the Central Cochrane Registry. The study included randomized clinical trials (RCTs) with vitamin C as an intervention arm in the septic patient population. For continuous variables, the difference in means (MD) and for discrete variables, the odds ratio (OR) was used. For effect sizes, a confidence interval of 95% was used. A p-value of less than 0.05 was used for statistical significance. The analysis was performed using a random-effects model irrespective of heterogeneity. Heterogeneity was evaluated using the I2 statistic. Results: 23 studies were included with the total sample size of 2712 patients. In patients treated with vitamin C, there was a statistically significant reduction in the mortality: OR = 0.778 (0.635 to 0.954), p = 0.016; the sequential organ failure assessment score (SOFA): MD = −0.749 (−1.115 to −0.383), p < 0.001; and the duration of vasopressor requirement: MD = −1.034 days (−1.622 to −0.445), p = 0.001. No significant difference was found in the hospital or ICU length of stay. Conclusions and clinical implications: Vitamin C treatment regimens were associated with reduced mortality, SOFA score, and vasopressor requirement compared to the control in sepsis. Given its low cost and minimal adverse effects, we strongly encourage further large, randomized trials to establish vitamin C as a standard of care in sepsis management.

Efficacy of High-Dose Vitamin C Infusion on Outcomes in Sepsis Requiring Mechanical Ventilation: A Double-Blind Randomized Controlled Trial

Background. Critically ill patients have an increased requirement for vitamin C in sepsis and these patients have low levels of vitamin C. The researchers validated the efficacy of high-dose vitamin C intravenous infusion (IVI) in patients with sepsis requiring mechanical ventilation. Methods. Forty patients were randomly assigned to 2 groups (20 each) in a 1 : 1 ratio in accordance with the vitamin C treatment regimen: Group I (GI): patients received 1.5 g/6 h vitamin C in 50 ml of dextrose 5% in water (D5W) IVI over 30 minutes for 4 consecutive days; Group II (GII): patients received 100 mg vitamin C/day as a first single dose in 50 ml of D5W IVI over 30 minutes and the other three subsequent doses were 50 ml of plain D5W IVI over 30 minutes for 4 consecutive days. Primary outcomes were the change in sequential organ failure assessment (SOFA) score at day 7, the incidence of ventilator-associated pneumonia (VAP), and the plasma vitamin C level. The glutathione peroxidase (GPX) activity, C-reactive protein (CRP) level, duration of vasopressor therapy, and 28-day mortality were secondary outcomes. Results. The change in SOFA score at day 7 showed a significant difference between GI and GII ( $p<0.001$ ). The incidence of early VAP was significantly lower in GI ( $p=0.044$ ). Vitamin C levels showed a significant rise in GI at day 1 and day 4 ( $p<0.001$ and $p<0.001$ , respectively). GPX activity of day 4 and day 7 was significantly higher in GI ( $p=0.005$ and $p=0.014$ , respectively). CRP levels of day 4 and day 7 were significantly higher in GII ( $p<0.001$ and $p<0.001$ , respectively). There was a significant difference in 28-day mortality ( $p=0.038$ ) and duration of vasopressor therapy ( $p=0.033$ ) in GI compared to GII. Conclusion. The early use of high-dose vitamin C intravenous infusion in patients with sepsis requiring mechanical ventilation in combination with the standard treatment for sepsis lowered the incidence of VAP, increased the antioxidant status, and improved the illness severity. Trial Registration. This trial is registered with ClinicalTrials.gov Identifier (NCT04029675).

Progress and Setbacks in Translating a Decade of Ferroptosis Research into Clinical Practice

Ten years after its initial description, ferroptosis has emerged as the most intensely studied entity among the non-apoptotic forms of regulated cell death. The molecular features of ferroptotic cell death and its functional role have been characterized in vitro and in an ever-growing number of animal studies, demonstrating that it exerts either highly detrimental or, depending on the context, occasionally beneficial effects on the organism. Consequently, two contrary therapeutic approaches are being explored to exploit our detailed understanding of this cell death pathway: the inhibition of ferroptosis to limit organ damage in disorders such as drug-induced toxicity or ischemia-reperfusion injury, and the induction of ferroptosis in cancer cells to ameliorate anti-tumor strategies. However, the path from basic science to clinical utility is rocky. Emphasizing ferroptosis inhibition, we review the success and failures thus far in the translational process from basic research in the laboratory to the treatment of patients.

Vitamin C-based regimens for sepsis and septic shock: Systematic review and meta-analysis of randomized clinical trials

PURPOSE

to critically appraise and synthesize the evidence on the effects of vitamin C-based regimens for patients with sepsis or septic shock.

METHODS

a broad search was performed on May 2021 to identify randomized clinical trials (RCTs) assessing vitamin C-based regimens as adjuvant therapy for adults with sepsis or septic shock. We used the Cochrane Risk of Bias table to assess the methodological quality of the included RCTs and the GRADE approach to evaluate the evidence certainty.

RESULTS

We included 20 RCTs (2124 participants). Evidence from low to very low certainty showed that vitamin C compared to placebo may reduce all-cause mortality up to 28 days (relative risk [RR] 0.60, 95% confidence interval (CI) 0.45 to 0.80, 4 RCTs, 335 participants). Considering the other comparisons (vitamin C alone or combined with thiamine and/or hydrocortisone, compared to placebo, standard care or hydrocortisone), there were a little to no difference or very uncertain evidence for adverse events, SOFA score, ICU length of stay, acute kidney injury, mechanical ventilation- and vasoactive drugs-free days up to 28 days.

CONCLUSION

Further RCTs with higher methodological quality, an increased number of participants and assessing clinically relevant outcomes are needed to provide better decision-making guidance.

PROSPERO REGISTER

CRD42021251786.

Oxidative Stress and Hyper-Inflammation as Major Drivers of Severe COVID-19 and Long COVID: Implications for the Benefit of High-Dose Intravenous Vitamin C

Oxidative stress is a pivotal point in the pathophysiology of COVID-19 and presumably also in Long-COVID. Inflammation and oxidative stress are mutually reinforcing each other, thus contributing to the systemic hyperinflammatory state and coagulopathy which are cardinal pathological mechanisms of severe stages. COVID-19 patients, like other critically ill patients e.g. with pneumonia, very often show severe deficiency of the antioxidant vitamin C. So far, it has not been investigated how long this deficiency lasts or whether patients with long COVID symptoms also suffer from deficiencies. A vitamin C deficit has serious pathological consequences because vitamin C is one of the most effective antioxidants, but also co-factor of many enzymatic processes that affect the immune and nervous system, blood circulation and energy metabolism. Because of its anti-oxidative, anti-inflammatory, endothelial-restoring, and immunomodulatory effects the supportive intravenous (iv) use of supraphysiological doses has been investigated so far in 12 controlled or observational studies with altogether 1578 inpatients with COVID-19. In these studies an improved oxygenation, a decrease in inflammatory markers and a faster recovery were observed. In addition, early treatment with iv high dose vitamin C seems to reduce the risks of severe courses of the disease such as pneumonia and also mortality. Persistent inflammation, thrombosis and a dysregulated immune response (auto-immune phenomena and/or persistent viral load) seem to be major contributors to Long-COVID. Oxidative stress and inflammation are involved in the development and progression of fatigue and neuro-psychiatric symptoms in various diseases by disrupting tissue (e.g. autoantibodies), blood flow (e.g. immune thrombosis) and neurotransmitter metabolism (e.g. excitotoxicity). In oncological diseases, other viral infections and autoimmune diseases, which are often associated with fatigue, cognitive disorders, pain and depression similar to Long-COVID, iv high dose vitamin C was shown to significantly relieve these symptoms. Supportive iv vitamin C in acute COVID-19 might therefore reduce the risk of severe courses and also the development of Long-COVID.

Low-Molecular-Weight Synthetic Antioxidants: Classification, Pharmacological Profile, Effectiveness and Trends

Mounting research has been performed and published on natural antioxidants, more so than on synthetic ones, as key molecules that control oxidative damage and its pathway to disease. Since the discovery of vitamins, various fully synthetic or natural-identical compounds have been developed as stable small molecules translated into constantly active and completely controlled products which are widely exploited in the food and pharmaceutical industries. There is currently a debate within the literature about their mechanism of action, bioavailability, safety and real benefit for human health. Using a semiquantitative method and eligible criteria of selection, this review aimed to provide a very useful classification of antioxidants and a comprehensive cross-disciplinary description of 32 approved synthetic/natural-identical antioxidants, in terms of regulatory, antioxidant mechanism of action, safety issues, pharmacological properties, effectiveness in human health, timeline and future trends. Enriched interpretation of the data was obtained from summary bibliometrics, useful to portray the “good antioxidant” within the period 1966–2021 and, hopefully, to encourage further research.

Vitamin C Plasma Levels Associated with Inflammatory Biomarkers, CRP and RDW: Results from the NHANES 2003–2006 Surveys

Although undisputed for its anti-inflammatory and immune system boosting properties, vitamin C remains an inconsistently investigated nutrient in the United States. However, subclinical inadequacies may partly explain increased inflammation and decreased immune function within the population. This secondary analysis cross-sectional study used the 2003–2006 NHANES surveys to identify more clearly the association between plasma vitamin C and clinical biomarkers of acute and chronic inflammation C-reactive protein (CRP) and red cell distribution width (RDW). From plasma vitamin C levels separated into five defined categories (deficiency, hypovitaminosis, inadequate, adequate, and saturating), ANOVA tests identified significant differences in means in all insufficient vitamin C categories (deficiency, hypovitaminosis, and inadequate) and both CRP and RDW in 7607 study participants. There were also statistically significant differences in means between sufficient plasma vitamin C levels (adequate and saturating categories) and CRP. Significant differences were not identified between adequate and saturating plasma vitamin C levels and RDW. Although inadequate levels of vitamin C may not exhibit overt signs or symptoms of deficiency, differences in mean levels identified between inflammatory biomarkers suggest a closer examination of those considered at risk for inflammatory-driven diseases. Likewise, the subclinical levels of inflammation presented in this study provide evidence to support ranges for further clinical inflammation surveillance.

New avenues of sepsis research: obtaining perspective by analyzing and comparing SSCG 2021 and J-SSCG 2020

Recently, revisions of two sepsis guidelines, namely, the Japanese Clinical Practice Guidelines for Management of Sepsis and Septic Shock 2020 and the Surviving Sepsis Campaign Guidelines 2021, were published. Although both guidelines were created in accordance with the Grading of Recommendations, Assessment, Development and Evaluation approach, the evidence-to-decision tables differed between them. In addition, certain recommendations may differ between these guidelines for similar clinical questions because of differences in the “PICO” criteria. Other differences in recommendations between the two guidelines are due to unclear evidence, and these ambiguities may provide the basis for further sepsis research. We hope that these two guidelines will contribute to the creation of new clinical evidence in addition to supporting treatment of patients with sepsis.

Is it time to reconsider the administration of thiamine alone or in combination with vitamin C in critically ill patients? A meta-analysis of clinical trial studies

Background

Although the effect of thiamine alone or in combination with vitamin C has been studied in multiple trials (RCT and interventional studies), their results are inconsistent. This meta-analysis aimed to assess impact of thiamine administration alone, thiamine in combination with vitamin C, and co-administration of low-dose hydrocortisone, vitamin C and thiamine (HVT) on clinical outcomes in critically ill patients.

Methods and materials

After electronic searches on PubMed, Scopus, Cochrane Library, and Web of Science databases, initially 3367 papers were found, and 20 interventional studies were included in our analysis. We assessed the risk-difference between treatment and control (standard treatment) groups by pooling available data on ICU length of stay, number of ventilator free days, mortality, and changes in Sequential Organ Failure Assessment (SOFA) scores.

Results

The results of present studies revealed no significant effect of thiamine in combination with vitamin C, and HVT on number of free days of ventilation. Thiamine alone supplementation was associated with high mortality percentage (WMD: 5.17%; 95% CI: 2.67, 7.67). Thiamine in combination with vitamin C had no significant impact on mortality rate. In contrast, HVT could decrease mortality rate (WMD: − 7.23%; 95% CI: − 10.31, − 4.16; I-square: 0.0%). There was no significant effect of thiamine alone, co-administration of thiamine and vitamin C, and HVT on ICU length of stay. The results of the meta-analysis showed that thiamine alone and HVT supplementation had no significant effect on SOFA score. Interestingly, co-supplementation of thiamine and vitamin C had a significant decreasing effect on SOFA score (WMD: − 0.73; 95% CI: − 1.29, − 0.17; I-square: 0.0%).

Conclusion

In contrast to HVT, thiamine supplementation alone was associated with increased mortality rate in ICU. However, co-supplementation of thiamine and vitamin C had a significant decreasing effect on SOFA score.

Thiamine, co-supplementation of thiamine and vitamin C and co-administration of hydrocortisone, vitamin C and thiamine (HVT) had no significant effect on free days of ventilation and ICU length of stay.

HVT could decrease and thiamine supplementation could increase mortality rate in ICU.

Co-supplementation of thiamine and vitamin C could decrease SOFA score.

Ascorbic acid attenuates activation and cytokine production in sepsis-like monocytes

Sepsis manifests due to the host's dysregulated immune response to infection. High-dose ascorbic acid (AA) has emerged as a potential treatment of sepsis, yet little is known regarding how AA influences the immune system in sepsis, such as monocytes. The objective of this study is to investigate the effects of high-dose AA on monocyte polarization and cytokine production in vitro. Monocytes isolated from healthy donors (n = 6) were polarized in vitro for 48 h using LPS or lipoteichoic acid (LTA). Polarization was confirmed by surface marker expression using flow cytometry. In parallel, monocytes from septic patients (n = 3) were analyzed for polarization markers as a comparison with the in vitro polarization. The effect of AA on monocyte polarization was then evaluated. Finally, monocytes were analyzed for cytokine production by intracellular staining. Both LPS and LTA induced polarization in healthy monocytes in vitro, with increased expression of both pro (M1) (CD40 and PDL1, p < 0.05) and anti-inflammatory (M2) (CD16 and CD163, p < 0.05) polarization markers. This pattern resembled that of monocytes from septic patients. Treatment with AA significantly inhibited surface expression of CD16 and CD163 (p < 0.05) in a dose-dependent manner. Finally, AA attenuated LPS- or LTA-induced cytokine production of IL-1ß, IL-6, IL-8, and TNF. In conclusion, AA attenuates proinflammatory cytokine production and diminishes up-regulation of CD16 and CD163, but not of CD40 and PDL-1 in LPS- or LTA-polarized monocytes. This study provides important insight into the effects of high-dose AA on monocytes and potential implications in sepsis.

Vitamin C for ≥ 5 days is associated with decreased hospital mortality in sepsis subgroups: a nationwide cohort study

Background

Previous randomized trials of vitamin C, hydrocortisone, and thiamine on sepsis were limited by short-term vitamin C administration, heterogeneous populations, and the failure to evaluate each component’s effect. The purpose of this study was to determine whether vitamin C alone for ≥ 5 days or in combination with corticosteroids and/or thiamine was associated with decreased mortality across the sepsis population and subpopulation.

Methods

Nationwide population-based study conducted using the Korean National Health Insurance Service database. A total of 384,282 adult patients with sepsis who were admitted to the intensive care unit were enrolled from January 2017 to December 2019. The primary outcome was hospital mortality, while the key secondary outcome was 90-day mortality.

Results

The mean [standard deviation] age was 69.0 [15.4] years; 57% were male; and 36,327 (9%) and 347,955 did and did not receive vitamin C, respectively. After propensity score matching, each group involved 36,327 patients. The hospital mortality was lower by − 0.9% in the treatment group (17.1% vs 18.0%; 95% confidence interval, − 1.3 to − 0.5%; p < 0.001), a significant but extremely small difference. However, mortality decreased greater in patients who received vitamin C for ≥ 5 days (vs 1–2 or 3–4 days) (15.8% vs 18.8% vs 18.3%; p < 0.001). Further, vitamin C was associated with a lower hospital mortality in patients with older age, multiple comorbidities, pneumonia, genitourinary infection, septic shock, and mechanical ventilation. Consistent findings were found for 90-day mortality. Moreover, vitamin C alone or in combination with thiamine was significantly associated with decreased hospital mortality.

Conclusions

Intravenous vitamin C of ≥ 5 days was significantly associated with decreased hospital and 90-day mortality in sepsis patients. Vitamin C combined with corticosteroids and/or thiamine in specific sepsis subgroups warrants further study.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13054-021-03872-3.

Comparison of the effects of vitamin C and thiamine on refractory hypotension in patients with sepsis: A randomized controlled trial

Background

The study aimed to compare the effect of thiamine and ascorbic acid (AA) on mortality, sequential organ failure assessment (SOFA) score, duration and dose of vasopressor support, and need for renal replacement therapy (RRT) in patients with septic shock with refractory hypotension.

Methods

Consenting adult patients with septic shock and refractory hypotension were included in this study. Patients were divided into three groups: Group A received 100 ml of balanced salt solution 8 hourly, Group B received 2 mg/kg of thiamine 8 hourly, Group C received 25 mg/kg of AA 8 hourly intravenous (IV) for 72 h. All patients received IV infusion of hydrocortisone 200 mg/day for 72 h. Serum lactate, dose and duration of vasopressor support, SOFA score, need for RRT and hospital mortality were analyzed.

Results

The SOFA Score was significantly lower in Group B than in Group A and C at 24, 48, and 72 h. Dosage of norepinephrine was lower in Group B at 66 h and after that, whereas in Groups A and C, it was comparable at all time points. Mortality in Group B was significantly lower but comparable in Groups A and C. The need for RRT was significantly lower in Group B (44%) compared to the control group (88%) but comparable in Group C (76%).

Conclusion

In patients with septic shock treated with hydrocortisone, co-treatment with thiamine led to earlier correction of organ dysfunction, reduced need for RRT, and improved mortality compared to patients treated with AA or balanced salt solution. The addition of AA did not yield measurable benefits beyond hydrocortisone alone.

Biomarker Analysis for Combination Therapy of Vitamin C and Thiamine in Septic Shock: A Post-Hoc Study of the ATESS Trial

INTRODUCTION

We evaluated the effects of vitamin C and thiamine administration on biomarkers in patients with septic shock.

METHODS

This was a post-hoc analysis of the Ascorbic Acid and Thiamine Effect in Septic Shock (ATESS) trial, a multicenter, double-blind, randomized controlled trial. Patients were randomized to either a treatment group (intravenous vitamin C and thiamine for 48 h) or a control group. Interleukin (IL)-6, IL-10, angiopoietin-II (AP2), and S100β were assessed at baseline and at 72 h. The primary outcomes were the biomarker levels at 72 h, and the secondary outcome was reduction rate.

RESULTS

Forty-five patients were assigned to the treatment group and 52 were assigned to the control group. Baseline biomarker levels and at 72 h were not significantly different between the treatment and the placebo groups. The reduction rates were not significantly different between the two groups. These outcome variables showed fair diagnostic accuracy for predicting 28-day mortality according to the area under the receiver operating characteristic curve.

CONCLUSION

Vitamin C and thiamine administration during the early phase of septic shock did not significantly change prognostic biomarker levels of IL-6, IL-10, AP2, and S100β.

TRIAL REGISTRATION

NCT, ClinicalTrials.gov NCT03756220, ATESS. Registered 28 November 2018, https://clinicaltrials.gov/ct2/show/NCT03756220.

Combination therapy of thiamine, vitamin C and hydrocortisone in treating patients with sepsis and septic shock: a meta-analysis and trial sequential analysis

Background

The objective of this study was to evaluate the clinical efficacy of thiamine and vitamin C with or without hydrocortisone coadministration on the treatment of sepsis and septic shock.

Methods

MEDLINE, EMBASE and CENTRAL databases were searched for randomized controlled trials (RCTs) that made a comparative study between the combination therapy of vitamin C and thiamine with or without hydrocortisone and the administration of placebo in patients with sepsis or septic shock. Two reviewers independently performed study selection, data extraction and quality assessment. Both short-term mortality and change in the sequential organ failure assessment (SOFA) score from baseline (delta SOFA) were set as the primary outcomes. Secondary endpoints included intensive care unit (ICU) mortality, new onset of acute kidney injury, total adverse events, ICU and hospital length of stay, duration of vasopressor usage and ventilator-free days. Meanwhile, trial sequential analysis was conducted for primary outcomes.

Results

Eight RCTs with 1428 patients were included in the current study. The results showed no significant reduction of short-term mortality in sepsis and septic shock patients who received combination therapy of vitamin C and thiamine with or without hydrocortisone compared to those with placebo {risk ratio (RR), 1.02 [95% confidence interval (CI), 0.87 to 1.20], p = 0.81, I² = 0%; risk difference (RD), 0 [95% CI, −0.04 to 0.05]}. Nevertheless, the combination therapy was associated with significant reduction in SOFA score [mean difference (MD), −0.63, (95% CI, −0.96 to −0.29, p < 0.001, I² = 0%] and vasopressors duration (MD, −22.11 [95% CI, −30.46 to −13.77], p < 0.001, I² = 6%). Additionally, there were no statistical differences in the pooled estimate for other outcomes.

Conclusions

In the current meta-analysis, the combination therapy of vitamin C and thiamine, with or without hydrocortisone had no impact on short-term mortality when compared with placebo, but was associated with significant reduction in SOFA score among patients with sepsis and septic shock.

Nutrition support for critically ill patients

Nutrition support is an important aspect of the management of critically ill patients. This review highlights the emerging evidence on critical care nutrition and focuses on the pathophysiologic interplay between critical illness, the gastrointestinal tract, and nutrition support and the evidence on the best route, dose, and timing of nutrition. Although indirect calorimetry is recommended to measure energy expenditure, predictive equations are commonly used but are limited by their inaccuracy in individual patients. The current evidence supports early enteral nutrition (EN) in most patients, with a gradual increase in the daily dose over the first week. Delayed EN is warranted in patients with severe shock. According to recent trials, parenteral nutrition seems to be as effective as EN and may be started if adequate EN is not achieved by the first week of critical illness. A high protein dose has been recommended, but the best timing is unclear. Immuno-nutrition should not be routinely provided to critically ill patients. Patients receiving artificial nutrition should be monitored for metabolic derangements. Additional adequately powered studies are still needed to resolve many unanswered questions.

Effect of IV High-Dose Vitamin C on Mortality in Patients With Sepsis: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

OBJECTIVES

The aim of this study was to conduct a systematic review and meta-analysis of randomized controlled trials to investigate whether IV high-dose vitamin C improves the short-term mortality of patients with sepsis.

DESIGN

This study is a systematic review and meta-analysis of randomized controlled trials. We searched EMBASE, the Cochrane Central Register of Controlled Trials, and MEDLINE for randomized controlled trials that met inclusion criteria. The protocol was registered at the University hospital Medical Information Network Clinical Trials Registry (UMIN000040528). All analyses were presented with the use of random-effects models. The primary outcome was short-term mortality defined as 28-day, 30-day, or in-hospital mortality.

PATIENTS

Two authors independently evaluated the following eligibility criteria: 1) randomized controlled trial, 2) patients with sepsis aged ≥18 years, and 3) received intravenous high-dose vitamin C in addition to standard of care, or standard of care alone. Then, two authors independently extracted the selected patient and study characteristics and outcomes from studies that met above eligibility criteria.

MEASUREMENTS AND MAIN RESULTS

Eleven randomized controlled trials (n = 1,737 patients) were included in this meta-analysis. High-dose IV vitamin C was not associated with a significantly lower short-term mortality (risk ratio, 0.88; 95% CI, 0.73-1.06; p = 0.18; I2 = 29%) but was associated with a significantly shorter duration of vasopressor use (standardized mean difference, -0.35; 95% CI, -0.63 to -0.07; p < 0.01; I2 = 80%) and a significantly greater decline in the Sequential Organ Failure Assessment score at 72-96 hours (standardized mean difference, -0.20; 95% CI, -0.32 to -0.08; p < 0.01; I2 = 16%). One study reported significant association with hypernatremia, but adverse effects were rare, and high-dose vitamin C is deemed relatively safe.

CONCLUSIONS

In this meta-analysis, the use of IV high-dose vitamin C in patients with sepsis was not associated with lower short-term mortality although it was associated with significantly shorter duration of vasopressor use and greater decline in the Sequential Organ Failure Assessment score at 72-96 hours.

Any Role of High-Dose Vitamin C for Septic Shock in 2021?

While the use of vitamin C as a therapeutic agent has been investigated since the 1950s, there has been substantial recent interest in the role of vitamin C supplementation in critical illness and particularly, sepsis and septic shock. Humans cannot synthesize vitamin C and rely on exogenous intake to maintain a plasma concentration of approximately 70 to 80 μmol/L. Vitamin C, in healthy humans, is involved with antioxidant function, wound healing, endothelial function, and catecholamine synthesis. Its function in the human body informs the theoretical basis for why vitamin C supplementation may be beneficial in sepsis/septic shock.Critically ill patients can be vitamin C deficient due to low dietary intake, increased metabolic demands, inefficient recycling of vitamin C metabolites, and loss due to renal replacement therapy. Intravenous supplementation is required to achieve supraphysiologic serum levels of vitamin C. While some clinical studies of intravenous vitamin C supplementation in sepsis have shown improvements in secondary outcome measures, none of the randomized clinical trials have shown differences between vitamin C supplementation and standard of care and/or placebo in the primary outcome measures of the trials. There are some ongoing studies of high-dose vitamin C administration in patients with sepsis and coronavirus disease 2019; the majority of evidence so far does not support the routine supplementation of vitamin C in patients with sepsis or septic shock.

Measuring vitamin C in critically ill patients: clinical importance and practical difficulties-Is it time for a surrogate marker?

This article is one of ten reviews selected from the Annual Update in Intensive Care and Emergency Medicine 2021. Other selected articles can be found online at  https://www.biomedcentral.com/collections/annualupdate2021 . Further information about the Annual Update in Intensive Care and Emergency Medicine is available from  https://link.springer.com/bookseries/8901 .

Efficacy of intravenous vitamin C intervention for septic patients: A systematic review and meta-analysis based on randomized controlled trials

BACKGROUND

The role of vitamin C in sepsis is still controversial, we aimed to systematically review the efficacy of intravenous vitamin C supplementation in the treatment of sepsis.

METHODS

MEDLINE, EmBase, Web of Science, WanFang Data and CNKI were comprehensively searched to collect randomized controlled trails (RCTs) of vitamin C supplementation for patients with sepsis or sepsis shock from January 2000 to March 2021. Two researchers independently screened the literature, extracted the data and accessed the risk of bias in the included studies; meta-analysis was then performed by using Revman 5.4 software.

RESULTS

A total of 10 RCTs involving 1400 participants were included. The results of meta-analysis showed that intravenous vitamin C supplementation can improve SOFA (ΔSOFA) within 72 h [RR = 1.32,95% CI(0.80,1.85), P < 0.0001] of septic patients. There were no difference on short term mortality (28-30d)[RR = 0.83,95% CI(0.65,1.05), P = 0.11], long term mortality (90d) [RR = 1.16,95% CI(0.82,1.66), P = 0.40], hospital LOS[RR = 0.15,95% CI(-0.73,1.03), P = 0.55], ventilator-free days[RR = 0.09,95% CI(-0.24,0.42), P = 0.60], ICU-LOS[RR = 0.22,95% CI(-0.13,0.57), P = 0.22], between two groups. The results of Subgroup analysis showed that intravenous vitamin C alone can reduce the risk of short term mortality (28-30d) [RR = 0.61,95% CI(0.47,0.79), P = 0.0002]of sepsis patients.

CONCLUSION

Based on current RCTs, our work indicated that mono-intravenous vitamin C therapy may reduce short-term mortality of sepsis patients, and it may protect organ functions. Due to the limitation of the quantity and quality of included studies, the above conclusions need to be verified by more large scale and high quality randomized control trials.

Ex Vivo Evaluation of the Sepsis Triple Therapy High-Dose Vitamin C in Combination with Vitamin B1 and Hydrocortisone in a Human Peripheral Blood Mononuclear Cells (PBMCs) Model

Sepsis is an extremely complex clinical syndrome, usually involving an excessive inflammatory response including an overshooting cytokine release that damages tissue and organs of the patient. Due to the severity of this condition, it is estimated that over 11 million people die from sepsis each year. Despite intensive research in the field, there is still no specific therapy for sepsis. Many sepsis patients show a marked deficiency of vitamin C. 9 out of 10 sepsis patients have a hypovitaminosis C, and every third patient even shows a clinical deficiency in the scurvy range. In addition, low vitamin C levels of intensive care sepsis patients correlate with a higher need for vasopressors, higher Sequential Organ Failure Assessment (SOFA) scores, and increased mortality. Based on this observation and the conducted clinical trials using vitamin C as sepsis therapy in intensive care patients, the aim of the present ex vivo study was to evaluate the effects of high-dose vitamin C alone and in a triple combination supplemented with vitamin B1 (thiamine) and hydrocortisone on the lipopolysaccharide (LPS)-induced cytokine response in peripheral blood mononuclear cells (PBMCs) from healthy human donors. We found that all corticosteroid combinations strongly reduced the cytokine response on RNA- and protein levels, while high-dose vitamin C alone significantly diminished the PBMC mediated secretion of the cytokines interleukin (IL)-10, IL-23, and monocyte chemo-attractant protein (MCP-1), which mediate the inflammatory response. However, vitamin C showed no enhancing effect on the secretion of further cytokines studied. This data provides important insights into the possible immunomodulatory function of vitamin C in an ex vivo setting of human PBMCs and the modulation of their cytokine profile in the context of sepsis. Since vitamin C is a vital micronutrient, the restoration of physiologically adequate concentrations should be integrated into routine sepsis therapy, and the therapeutic effects of supraphysiological concentrations of vitamin C in sepsis patients should be further investigated in clinical trials.

Prevalence of Hypovitaminosis C and its Relationship with Frailty in Older Hospitalised Patients: A Cross-Sectional Study

Frailty is common in older hospitalised patients and may be associated with micronutrient malnutrition. Only limited studies have explored the relationship between frailty and vitamin C deficiency. This study investigated the prevalence of vitamin C deficiency and its association with frailty severity in patients ≥75 years admitted under a geriatric unit. Patients (n = 160) with a mean age of 84.4 ± 6.4 years were recruited and underwent frailty assessment by use of the Edmonton Frail Scale (EFS). Patients with an EFS score <10 were classified as non-frail/vulnerable/mildly frail and those with ≥10 as moderate–severely frail. Patients with vitamin C levels between 11–28 μmol/L were classified as vitamin C depleted while those with levels <11 μmol/L were classified as vitamin C deficient. A multivariate logistic regression model determined the relationship between vitamin C deficiency and frailty severity after adjustment for various co-variates. Fifty-seven (35.6%) patients were vitamin C depleted, while 42 (26.3%) had vitamin C deficiency. Vitamin C levels were significantly lower among patients who were moderate–severely frail when compared to those who were non-frail/vulnerable/mildly frail (p < 0.05). After adjusted analysis, vitamin C deficiency was 4.3-fold more likely to be associated with moderate–severe frailty (aOR 4.30, 95% CI 1.33-13.86, p = 0.015). Vitamin C deficiency is common and is associated with a greater severity of frailty in older hospitalised patients.

Safety and effectiveness of high-dose vitamin C in patients with COVID-19: a randomized open-label clinical trial

Background

Vitamin C is an essential water-soluble nutrient that functions as a key antioxidant and has been proven to be effective for boosting immunity. In this study, we aimed to assess the efficacy of adding high-dose intravenous vitamin C (HDIVC) to the regimens for patients with severe COVID-19 disease.

Methods

An open-label, randomized, and controlled trial was conducted on patients with severe COVID-19 infection. The case and control treatment groups each consisted of 30 patients. The control group received lopinavir/ritonavir and hydroxychloroquine and the case group received HDIVC (6 g daily) added to the same regimen.

Results

There were no statistically significant differences between two groups with respect to age and gender, laboratory results, and underlying diseases. The mean body temperature was significantly lower in the case group on the 3rd day of hospitalization (p = 0.001). Peripheral capillary oxygen saturations (SpO₂) measured at the 3rd day of hospitalization was also higher in the case group receiving HDIVC (p = 0.014). The median length of hospitalization in the case group was significantly longer than the control group (8.5 days vs. 6.5 days) (p = 0.028). There was no significant difference in SpO₂ levels at discharge time, the length of intensive care unit (ICU) stay, and mortality between the two groups.

Conclusions

We did not find significantly better outcomes in the group who were treated with HDIVC in addition to the main treatment regimen at discharge.

Trial registration irct.ir (IRCT20200411047025N1), April 14, 2020