Vitamin C, Thiamine, and Hydrocortisone in the Treatment of Sepsis: A Meta-Analysis and Trial Sequential Analysis of Randomized Controlled Trials

Combined treatment with vitamin C, hydrocortisone and thiamine does not attenuate morbidity and mortality of septic sheep

BACKGROUND

Sepsis is associated with a highest mortality rate in the ICU. Present study tests the efficacy of combined therapy with vitamin C, hydrocortisone and thiamine (combined therapy) in the ovine model of sepsis induced by Pseudomonas aeruginosa. In this study, sepsis was induced in sheep by instillation of Pseudomonas aeruginosa (1 × 1011 CFU) into the lungs via bronchoscope, under anesthesia. Nine hours after injury, intravenous infusion of vitamin C (0.75 g every 6 h), hydrocortisone (25 mg every 6 h), and thiamine (100 mg every 12 h) or saline was given to the treatment and control groups. Cardiopulmonary variables were recorded.

RESULTS

The survival rate was 16.7% in control and 33.3% in treatment groups. In the control group, mean arterial pressure dropped from 93.6 ± 8.6 to 75.5 ± 9.7 mmHg by 9 h, which was not affected by the combined therapy. Pulmonary dysfunction was not attenuated by the combined therapy either. The combined therapy had no effect on increased extravascular lung water content and fluid effusion into thoracic cavity. The bacterial number in the bronchoalveolar lavage fluid was significantly increased in the treatment group than the control group. The blood bacterial number remained comparable between groups.

CONCLUSIONS

Combined vitamin C, hydrocortisone, and thiamine did not attenuate severity of ovine sepsis.

Metabolic failure due to thiamine deficiency during critical illness

PURPOSE OF REVIEW

Thiamine is a crucial component in cellular energy metabolism, serving as a cofactor for multiple enzymatic processes and also having a role in regulating neuronal and neuromuscular transmission. Also it exerts antioxidant proprieties. The objective of this review is to consolidate and assess the most recent research concerning the consequences of insufficient thiamine levels for critically ill patients and to examine thiamine-related interventions.

RECENT FINDINGS

Recent studies have unveiled a noteworthy association between thiamine deficiency and unfavorable consequences, such as heightened morbidity and fatality rates. The aforementioned deficiency exhibits a significant presence in medical situations such as starvation and alcohol use disorder, but also in patients during critical illness. Thiamine deficiency can have significant metabolic implications resulting in compromised energy generation and organ dysfunction, warranting prompt recognition and management.

SUMMARY

Thiamine deficiency may not be recognized in critical care. Timely identification and management are imperative to mitigate adverse outcomes and improve patient prognosis. Thiamine may offer benefits for specific patient groups at higher risk of deficiency. Future studies should focus to establish optimal dosing, timing, and monitoring strategies on understanding the pathophysiological changes associated with thiamine deficiency in ICU patients and clarify its role in improving clinical outcomes.

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/.

[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.

The outcome of IV vitamin C therapy in patients with sepsis or septic shock: a meta-analysis of randomized controlled trials

BACKGROUND

To update a meta-analysis of randomized controlled trials (RCTs) and further explore the outcome of IV vitamin C (IVVC) administration in sepsis or septic shock patients.

METHODS

This study is a meta-analysis of RCTs. The RCTs of vitamin C therapy in sepsis or septic shock were searched in PubMed, EMBASE and Clinical Trials.gov from inception to January 16, 2023. We registered the protocol with PROSPERO (CRD42022354875). The primary outcome was delta Sequential Organ Failure Assessment (SOFA) score at 72-96 h. Two reviewers independently assessed RCTs according to eligibility criteria: (1) study type: RCT; (2) patient population: patients ≥ 18 years with sepsis or septic shock; (3) intervention: IVVC at any doses as monotherapy or combined with thiamine or and hydrocortisone compared with standard of care, no intervention or placebo (defined as control group); (4) the RCT described short-term mortality or SOFA score. Then, two authors independently extracted related information from RCTs.

RESULTS

Eighteen RCTs (n = 3364 patients) were identified in this meta-analysis. There were significant effects in the delta SOFA score from baseline to 72-96 h (MD, - 0.62; 95% CI, - 1.00 to - 0.25; p = 0.001) and the duration of vasopressor use (MD, - 15.07; 95% CI, - 21.59 to - 8.55; p < 0.00001) with IVVC therapy. Treatment with IVVC was not shown to improve short-term mortality (OR, 0.89; 95% CI, 0.77 to 1.04; p = 0.14); nevertheless, dose at 25-100 mg/kg/d subgroup associated with a significant reduction in short-term mortality (OR, 0.80; 95% CI, 0.65 to 0.97; p = 0.03). An increase adverse event was observed in IVVC therapy (OR, 1.98; 95% CI, 1.06 to 3.68; p = 0.03).

CONCLUSION

In this meta-analysis, IVVC in sepsis or septic shock patients significantly improved delta SOFA score and reduced the duration of vasopressor use, whereas it was not associated with reduction in short-term mortality and had higher adverse events.

Medical nutrition therapy in patients receiving ECMO: Evidence-based guidance for clinical practice

Patients receiving extracorporeal membrane oxygenation (ECMO) inherit substantial disease-associated metabolic, endocrinologic, and immunologic modifications. Along with the technical components of ECMO, the aforementioned alterations may affect patients' needs and feasibility of adequate macronutrient and micronutrient supply and intake. Thus, patients receiving ECMO are at increased risk for iatrogenic malnutrition and require targeted individual medical nutrition therapy (MNT). However, specific recommendations for MNT in patients receiving ECMO are limited and, with some exceptions, based on an evidence base encompassing general patients who are critically ill. Consequently, clinician decision-making for MNT in patients receiving ECMO is unguided, which may further increase nutrition risk, culminating in iatrogenic malnutrition and ultimately affecting patient outcomes. The purpose of this article is to provide educational background and highlight specific points for MNT in adult patients receiving ECMO, which might serve as evidence-based guidance to develop institutional standard operating procedures and nutrition protocols for daily clinical practice.

Impact of supplemental thiamin on lactate levels in adults with septic shock

BACKGROUND

Elevated lactate levels at 24 h are highly predictive of in-hospital mortality in adults with septic shock. Thiamin is closely involved in carbohydrate metabolism, and in thiamin-deficient states, increased lactic acid levels can be found, exacerbated by critical illness. This integrative literature review focused on the relationship between supplemental thiamin, lactate clearance, and impact on mortality in sepsis.

METHODS

A search in PubMed, Embase, and CINAHL was conducted for literature published between January 2016 and January 2021. We included observational studies and clinical trials with ≥10 participants. We excluded studies involving pediatric (<18 years old) populations, animal studies, case studies, dropout rate of >20%, nonhospitalized patients, or patients receiving comfort measures only.

RESULTS

A total of 48 full-text articles were assessed for eligibility, with 15 evaluated for this integrative review. Included were five retrospective, two prospective observational, and eight randomized controlled trials. In almost all retrospective studies, thiamin administration was associated with decreased mortality, and in observational studies, with decreased lactate and improved clinical outcomes. In clinical trials, thiamin with or without vitamin C/hydrocortisone did not impact clinical outcomes or mortality. However, four trials testing intravenous thiamin 200-500 mg two to three times daily for up to 3 days reported improved lactate clearance.

CONCLUSIONS

Thiamin supplementation may improve lactate clearance when administered in the first 24 h. Those deficient in thiamin may benefit more from supplementation. The combination of thiamin, vitamin C, and/or hydrocortisone may not be advantageous. Lactate reduction in response to thiamin needs further rigorous research.

IV Vitamin C in Sepsis: A Latest Systematic Review and Meta-Analysis

Sepsis is a high-incidence disease and demands intensive care. Finding effective treatment is the key to cure sepsis. Studies have shown a lower level of vitamin C in patients with sepsis. Therefore, vitamin C supplementation has become one of the measures to treat sepsis. However, the clinical studies of vitamin C in the treatment of sepsis have been controversial. We performed a meta-analysis to evaluate vitamin C's efficacy and safety in the treatment of sepsis. We searched four electronic databases: PubMed, Embase, Web of Science, and the Cochrane Library, and two researchers independently screened 24 eligible RCTs published in English. Our review demonstrates that intravenous (IV) vitamin C might improve short-term mortality (RR, 0.82; 95% CI, 0.65-1.02; P=0.07; and I ² = 45%) and overall mortality (RR, 0.86; 95% CI, 0.74-1.01; P=0.06; and I ² = 51%) of patients with sepsis. Moreover, the SOFA score of patients with sepsis improved significantly after treatment with vitamin C for over 72 hours (RR, 0.26; 95% CI, 0.09-0.42; P=0.002; and I ² = 0%). The main results of our study were moderate-quality evidence. More high-quality, multicenter RCTs are needed to provide more substantial evidence on the efficacy and safety of IV vitamin C for sepsis.

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.

HYDROCORTISONE, ASCORBIC ACID, AND THIAMINE THERAPY DECREASE RENAL OXIDATIVE STRESS AND ACUTE KIDNEY INJURY IN MURINE SEPSIS

ABSTRACT

Background: Acute kidney injury (AKI) occurs frequently in septic patients and correlates with increased mortality. Because clinical studies investigating hydrocortisone, ascorbic acid, and thiamine (HAT) have demonstrated discordant results, studies were performed using mortality stratification for therapy to identify candidates for therapy and determine mechanisms of organ injury. Methods: Sepsis was induced using the cecal ligation and puncture (CLP) model of sepsis with fluid and antibiotic support. Heart rate (HR) measurements obtained 6 hours after CLP stratified mice into live predicted (P-Live) or die predicted (P-Die). Stratified mice were then randomized for treatment with HAT or vehicle given 7 hours after CLP. Physiologic measurements were taken again at 24 hours, and mice were killed to collect blood and organs. Results: The following five groups were created: (1) P-Live vehicle, (2) P-Live HAT, (3) P-Die vehicle, (4) P-Die HAT, and (5) naive mice. Comparisons were made to test the hypotheses that (1) P-Die vehicle mice will have significant deterioration compared with P-Live mice targeting the kidney and (2) HAT will correct these deleterious changes in P-Die mice. Compared with P-Live, P-Die mice had a significant decline in all measured physiologic parameters (HR, cardiac output, breath rate, and temperature), which were corrected with HAT therapy (P < 0.05 for all parameters). The P-Die mice had declines in the ascorbic acid within the blood, peritoneal lavage, and kidney homogenate compared with P-Live mice indicating consumption, and the decline was corrected with HAT. Elevated IL-6, KC, Macrophage Inflammatory Protein-2, and IL-1RA were found in P-Die mice and decreased with HAT. Markers of endothelial cell injury (glypican 1 and glypican 4) were elevated in the P-Die mice, and these values were decreased with HAT therapy. Low oxygen levels with subsequent oxidative stress (OS) in the kidney were visualized in histologic sections using hypoxyprobe and also with carbonyl proteins and 8-iso-prostaglandin F2α in kidney homogenates. The P-Die mice had significant elevations of renal OSs, which was ameliorated with HAT. Kidney injury was evident in the P-Die mice compared with P-Live mice with elevations in blood urea nitrogen and cystatin C, which were significantly reduced with HAT. There was no evidence of global hypoxia or organ injury because hepatic parameters remained normal. Conclusions: Our data show that in CLP-induced sepsis, P-Die mice have increased inflammation, OS, and kidney injury. Hydrocortisone, ascorbic acid, and thiamine therapy decreased renal OS and injury in the P-Die group when given after the onset of sepsis-induced physiologic changes.

The effect of intravenous vitamin C on clinical outcomes in patients with sepsis or septic shock: A meta-analysis of randomized controlled trials

Objectives

Vitamin C deficiency is common among patients with sepsis and has been associated with poor clinical outcomes. Nevertheless, the effect of intravenous (IV) vitamin C for the treatment of sepsis remains controversial. The purpose of this meta-analysis was to evaluate the effect of IV vitamin C in patients with sepsis or septic shock.

Methods

Electronic databases (PubMed, Embase, Scopus, and Cochrane Library) were searched from inception through May 25, 2022 for randomized controlled trials evaluating the effect of IV vitamin C treatment in patients with sepsis. The primary outcome was short-term mortality, and secondary outcomes including the duration of vasopressor, length of intensive care unit (ICU) stay, and Sequential Organ Failure Assessment (SOFA) score after vitamin C treatment. Subgroup analyses were performed based on the type of disease, dose and duration of IV vitamin C.

Results

A total of 10 studies were included, with a total sample of 755 septic patients. The IV vitamin C was associated with a significant reduction in the short-term mortality (OR 0.51, 95% CI 0.37–0.69, I² = 0%) and duration of vasopressor (MD −27.88, 95% CI −49.84 to −5.92, I² = 95%). The length of ICU stay (MD −0.68, 95% CI −2.13 to 0.78, I² = 74%) and SOFA score (MD −0.05, 95% CI −1.69 to 1.58, I² = 86%) were not significantly different between two groups.

Conclusion

In patients with sepsis or septic shock, the IV vitamin C reduced the short-term mortality rate and duration of vasopressor, with no effect on the length of ICU stay and SOFA score. Further trials are required to explore the optimal dosage and duration of IV vitamin C.

Systematic Review Registration

https://inplasy.com/inplasy-2022-6-0013/, identifier INPLASY202260013.

[Resuscitation strategy for patients with sepsis and septic shock]

Fluid and vasopressor resuscitation is, along with antimicrobial therapy and control of the focus of infection, a basic issue of the treatment of sepsis and septic shock. There is currently no accepted protocol that we can follow for the resuscitation of these patients and the Surviving Sepsis Campaign proposes controversial measures and without sufficient evidence support to establish firm recommendations. We propose a resuscitation strategy adapted to the situation of each patient: in the patient in whom community sepsis is suspected, we consider that the early administration of 30mL/kg of crystalloids is effective and safe; in the patient with nosocomial sepsis, we must carry out a more in-depth evaluation before initiating aggressive resuscitation. In patients who do not respond to initial resuscitation, it is necessary to increase monitoring level and, depending on the hemodynamic profile, administer more fluids, a second vasopressor or inotropes.

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.

Insights Into Thiamine Supplementation in Patients With Septic Shock

Septic shock is associated with unacceptably high mortality rates, mainly in developing countries. New adjunctive therapies have been explored to reduce global mortality related to sepsis. Considering that metabolic changes, mitochondrial dysfunction and increased oxidative stress are specific disorders within the path of septic shock, several micronutrients that could act in cellular homeostasis have been studied in recent decades. Thiamine, also known as vitamin B1, plays critical roles in several biological processes, including the metabolism of glucose, synthesis of nucleic acids and reduction of oxidative stress. Thiamine deficiency could affect up to 70% of critically ill patients, and thiamine supplementation appears to increase lactate clearance and decrease the vasopressor dose. However, there is no evident improvement in the survival of septic patients. Other micronutrients such as vitamin C and D, selenium and zinc have been tested in the same context but have not been shown to improve the outcomes of these patients. Some problems related to the neutrality of these clinical trials are the study design, doses, route, timing, length of intervention and the choice of endpoints. Recently, the concept that multi-micronutrient administration may be better than single-micronutrient administration has gained strength. In general, clinical trials consider the administration of a single micronutrient as a drug. However, the antioxidant defense is a complex system of endogenous agents in which micronutrients act as cofactors, and the physiological interactions between micronutrients are little discussed. In this context, the association of thiamine, vitamin C and corticoids was tested as an adjunctive therapy in septic shock resulting in a significant decrease in mortality. However, after these initial results, no other study conducted with this combination could reproduce those benefits. In addition, the use of low-dose corticosteroids is recommended in patients with septic shock who do not respond to vasopressors, which can affect the action of thiamine. Therefore, given the excellent safety profile, good biologic rationale and promising clinical studies, this review aims to discuss the mechanisms behind and the evidence for single or combined thiamine supplementation improving the prognosis of patients with septic shock.

Hydrocortisone, ascorbic acid, and thiamine (HAT) for sepsis and septic shock: a meta-analysis with sequential trial analysis

BACKGROUND

Sepsis is a primary global health threat and costs a lot, requiring effective and affordable treatments. We performed this meta-analysis to explore the treatment of hydrocortisone, ascorbic acid, and thiamine (HAT) in sepsis and septic shock.

METHODS

We searched Ovid MEDLINE, Embase, and the Cochrane Central Register of Controlled Trials from inception to August 14, 2021. We included randomized controlled trials (RCTs) that evaluated the HAT treatments in sepsis and septic shock. The primary outcome was the change in SOFA score over the 72 h. The second outcomes were the hospital, and 28-/30-day mortality, the duration of vasopressors, PCT clearance, hospital length of stay (LOS), and ICU LOS. We performed a subgroup analysis and a trial sequential analysis (TSA). The Der Simonian-Laird random-effects models were used to report the pooled risk ratios (RR) or mean difference (MD) with confidence intervals (CI).

RESULTS

Nine RCTs, enrolling 1427 patients of sepsis and septic shock treated with HAT (717) or only standard care (710), were included. There was a significant difference between the two groups in the change in SOFA score over the first 72 h (MD 0.65, 95% CI 0.30 to 1.00), the duration of vasopressors (MD - 18.16, 95% CI - 25.65 to - 10.68) and the PCT clearance (MD 14.54, 95% CI 0.64 to 28.43). In addition, there was no significant difference in the hospital mortality (RR 1.07, 95% CI 0.85 to 1.34), the 28-/30-day mortality (RR 0.96, 95% CI 0.80 to 1.15), the hospital LOS (MD 0.78, 95% CI - 0.30 to 1.86), and ICU LOS (MD 0.12, 95% CI - 0.53 to 0.78).

CONCLUSIONS

The HAT combination improves the SOFA score in the first 72 h and reduces the duration of vasopressors in patients with sepsis. Given the minor mean difference of the change in SOFA score, the mortality benefit has not been observed.

TRIAL REGISTRATION

PROSPERO, CRD42020203166.

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.

Kidney Microcirculation as a Target for Innovative Therapies in AKI

Acute kidney injury (AKI) is a serious multifactorial conditions accompanied by the loss of function and damage. The renal microcirculation plays a crucial role in maintaining the kidney’s functional and structural integrity for oxygen and nutrient supply and waste product removal. However, alterations in microcirculation and oxygenation due to renal perfusion defects, hypoxia, renal tubular, and endothelial damage can result in AKI and the loss of renal function regardless of systemic hemodynamic changes. The unique structural organization of the renal microvasculature and the presence of autoregulation make it difficult to understand the mechanisms and the occurrence of AKI following disorders such as septic, hemorrhagic, or cardiogenic shock; ischemia/reperfusion; chronic heart failure; cardiorenal syndrome; and hemodilution. In this review, we describe the organization of microcirculation, autoregulation, and pathophysiological alterations leading to AKI. We then suggest innovative therapies focused on the protection of the renal microcirculation and oxygenation to prevent AKI.

Nutrition in the Intensive Care Unit-A Narrative Review

Background: While consent exists, that nutritional status has prognostic impact in the critically ill, the optimal feeding strategy has been a matter of debate. Methods: Narrative review of the recent evidence and international guideline recommendations focusing on basic principles of nutrition in the ICU and the treatment of specific patient groups. Covered topics are: the importance and diagnosis of malnutrition in the ICU, the optimal timing and route of nutrition, energy and protein requirements, the supplementation of specific nutrients, as well as monitoring and complications of a Medical Nutrition Therapy (MNT). Furthermore, this review summarizes the available evidence to optimize the MNT of patients grouped by primarily affected organ system. Results: Due to the considerable heterogeneity of the critically ill, MNT should be carefully adapted to the individual patient with special focus on phase of critical illness, metabolic tolerance, leading symptoms, and comorbidities. Conclusion: MNT in the ICU is complex and requiring an interdisciplinary approach and frequent reevaluation. The impact of personalized and disease-specific MNT on patient-centered clinical outcomes remains to be elucidated.