Use of Hydrocortisone, Ascorbic Acid, and Thiamine in Adults with Septic Shock

Effectiveness of Fludrocortisone Plus Hydrocortisone versus Hydrocortisone Alone in Septic Shock: A Systematic Review and Network Meta-Analysis of Randomized Controlled Trials

Rationale: The use of hydrocortisone in adult patients with septic shock is controversial, and the effectiveness of adding fludrocortisone to hydrocortisone remains uncertain. Objectives: To assess the comparative effectiveness and safety of fludrocortisone plus hydrocortisone, hydrocortisone alone, and placebo or usual care in adults with septic shock. Methods: A systematic review and a Bayesian network meta-analysis of peer-reviewed randomized trials were conducted. The primary outcome was all-cause mortality at last follow-up. Treatment effects are presented as relative risks (RRs) with 95% credible intervals (CrIs). Placebo or usual care was the reference treatment. Measurements and Main Results: Among 7,553 references, we included 17 trials (7,688 patients). All-cause mortality at last follow-up was lowest with fludrocortisone plus hydrocortisone (RR, 0.85; 95% CrI, 0.72-0.99; 98.3% probability of superiority, moderate-certainty evidence), followed by hydrocortisone alone (RR, 0.97; 95% CrI, 0.87-1.07; 73.1% probability of superiority, low-certainty evidence). The comparison of fludrocortisone plus hydrocortisone versus hydrocortisone alone was based primarily on indirect evidence (only two trials with direct evidence). Fludrocortisone plus hydrocortisone was associated with a 12% lower risk of all-cause mortality compared with hydrocortisone alone (RR, 0.88; 95% CrI, 0.74-1.03; 94.2% probability of superiority, moderate-certainty evidence). Conclusions: In adult patients with septic shock, fludrocortisone plus hydrocortisone was associated with lower risk of all-cause mortality at last follow-up than placebo and hydrocortisone alone. The scarcity of head-to-head trials comparing fludrocortisone plus hydrocortisone versus hydrocortisone alone led our network meta-analysis to rely primarily on indirect evidence for this comparison. Although we undertook several sensitivity analyses and assessments, these findings should be considered while also acknowledging the heterogeneity of included trials.

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.

Intravenous Vitamin C for Patients Hospitalized With COVID-19: Two Harmonized Randomized Clinical Trials

Importance

The efficacy of vitamin C for hospitalized patients with COVID-19 is uncertain.

Objective

To determine whether vitamin C improves outcomes for patients with COVID-19.

Design, Setting, and Participants

Two prospectively harmonized randomized clinical trials enrolled critically ill patients receiving organ support in intensive care units (90 sites) and patients who were not critically ill (40 sites) between July 23, 2020, and July 15, 2022, on 4 continents.

Interventions

Patients were randomized to receive vitamin C administered intravenously or control (placebo or no vitamin C) every 6 hours for 96 hours (maximum of 16 doses).

Main Outcomes and Measures

The primary outcome was a composite of organ support-free days defined as days alive and free of respiratory and cardiovascular organ support in the intensive care unit up to day 21 and survival to hospital discharge. Values ranged from -1 organ support-free days for patients experiencing in-hospital death to 22 organ support-free days for those who survived without needing organ support. The primary analysis used a bayesian cumulative logistic model. An odds ratio (OR) greater than 1 represented efficacy (improved survival, more organ support-free days, or both), an OR less than 1 represented harm, and an OR less than 1.2 represented futility.

Results

Enrollment was terminated after statistical triggers for harm and futility were met. The trials had primary outcome data for 1568 critically ill patients (1037 in the vitamin C group and 531 in the control group; median age, 60 years [IQR, 50-70 years]; 35.9% were female) and 1022 patients who were not critically ill (456 in the vitamin C group and 566 in the control group; median age, 62 years [IQR, 51-72 years]; 39.6% were female). Among critically ill patients, the median number of organ support-free days was 7 (IQR, -1 to 17 days) for the vitamin C group vs 10 (IQR, -1 to 17 days) for the control group (adjusted proportional OR, 0.88 [95% credible interval {CrI}, 0.73 to 1.06]) and the posterior probabilities were 8.6% (efficacy), 91.4% (harm), and 99.9% (futility). Among patients who were not critically ill, the median number of organ support-free days was 22 (IQR, 18 to 22 days) for the vitamin C group vs 22 (IQR, 21 to 22 days) for the control group (adjusted proportional OR, 0.80 [95% CrI, 0.60 to 1.01]) and the posterior probabilities were 2.9% (efficacy), 97.1% (harm), and greater than 99.9% (futility). Among critically ill patients, survival to hospital discharge was 61.9% (642/1037) for the vitamin C group vs 64.6% (343/531) for the control group (adjusted OR, 0.92 [95% CrI, 0.73 to 1.17]) and the posterior probability was 24.0% for efficacy. Among patients who were not critically ill, survival to hospital discharge was 85.1% (388/456) for the vitamin C group vs 86.6% (490/566) for the control group (adjusted OR, 0.86 [95% CrI, 0.61 to 1.17]) and the posterior probability was 17.8% for efficacy.

Conclusions and Relevance

In hospitalized patients with COVID-19, vitamin C had low probability of improving the primary composite outcome of organ support-free days and hospital survival.

Trial Registration

ClinicalTrials.gov Identifiers: NCT04401150 (LOVIT-COVID) and NCT02735707 (REMAP-CAP).

Patient Outcomes After Long-Term Acute Care Hospital Closures

Importance

Long-term acute care hospitals (LTCHs) are common sites of postacute care for patients recovering from severe respiratory failure requiring mechanical ventilation (MV). However, federal payment reform led to the closure of many LTCHs in the US, and it is unclear how closure of LTCHs may have affected upstream care patterns at short-stay hospitals and overall patient outcomes.

Objective

To estimate the association between LTCH closures and short-stay hospital care patterns and patient outcomes.

Design, Setting, and Participants

This retrospective, national, matched cohort study used difference-in-differences analysis to compare outcomes at short-stay hospitals reliant on LTCHs that closed during 2012 to 2018 with outcomes at control hospitals. Data were obtained from the Medicare Provider Analysis and Review File, 2011 to 2019. Participants included Medicare fee-for-service beneficiaries aged 66 years and older receiving MV for at least 96 hours in an intensive care unit (ie, patients at-risk for prolonged MV) and the subgroup also receiving a tracheostomy (ie, receiving prolonged MV). Data were analyzed from October 2022 to June 2023.

Exposure

Admission to closure-affected hospitals, defined as those discharging at least 60% of patients receiving a tracheostomy to LTCHs that subsequently closed, vs control hospitals.

Main Outcomes and Measures

Upstream hospital care pattern outcomes were short-stay hospital do-not-resuscitate orders, palliative care delivery, tracheostomy placement, and discharge disposition. Patient outcomes included hospital length of stay, days alive and institution free within 90 days, spending per days alive within 90 days, and 90-day mortality.

Results

Between 2011 and 2019, 99 454 patients receiving MV for at least 96 hours at 1261 hospitals were discharged to 459 LTCHs; 84 LTCHs closed. Difference-in-differences analysis included 8404 patients (mean age, 76.2 [7.2] years; 4419 [52.6%] men) admitted to 45 closure-affected hospitals and 45 matched-control hospitals. LTCH closure was associated with decreased LTCH transfer rates (difference, -5.1 [95% CI -8.2 to -2.0] percentage points) and decreased spending-per-days-alive (difference, -$8701.58 [95% CI, -$13 323.56 to -$4079.60]). In the subgroup of patients receiving a tracheostomy, there was additionally an increase in do-not-resuscitate rates (difference, 10.3 [95% CI, 4.2 to 16.3] percentage points) and transfer to skilled nursing facilities (difference, 10.0 [95% CI, 4.2 to 15.8] percentage points). There was no significant association of closure with 90-day mortality.

Conclusions and Relevance

In this cohort study, LTCH closure was associated with changes in discharge patterns in patients receiving mechanical ventilation for at least 96 hours and advanced directive decisions in the subgroup receiving a tracheostomy, without change in mortality. Further studies are needed to understand how LTCH availability may be associated with other important outcomes, including functional outcomes and patient and family satisfaction.

HAT therapy for sepsis: A review of the therapeutic rationale and current clinical evaluation status

Vitamin C-based cluster therapy, which involves the combined application of hydrocortisone, vitamin C, and thiamine (HAT), is a recently proposed new treatment option for sepsis on top of conventional treatment. This therapy has a strong theoretical basis, but its clinical efficacy remains inconclusive. This review summarizes the rationale for HAT therapy for sepsis and describes the evaluation of its efficacy in clinical observational studies and randomized controlled trials, with the aim of providing a reference for the future clinical practice application of HAT therapy in sepsis.

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.

First-line Vasopressor Use in Septic Shock and Route of Administration: An Epidemiologic Study

RATIONALE

Norepinephrine is a first-line agent for treatment of hypotension in septic shock. However, its frequency of use, and potential barriers to its use are unclear.

OBJECTIVES

To evaluate the frequency of use of norepinephrine in septic shock, to identify potential barriers to its use, and to evaluate trends in use of vasopressors over time.

METHODS

Retrospective population-based cohort study of patients with septic shock in Alberta, Canada between July 1, 2012 and December 31, 2018. The primary outcome was receipt of a first-line vasopressor other than norepinephrine ("non-norepinephrine vasopressor"). Predictors of receiving a non-norepinephrine vasopressor were assessed using a multivariable-adjusted, multilevel logistic regression model with intensive care unit (ICU) as a random effect.

RESULTS

Among 6343 patients with septic shock, the proportion of patients receiving non-norepinephrine vasopressors as first-line treatment decreased steadily from 11.5% in 2012 to 3.0% in 2018. Two factors most strongly associated with their receipt were having peripheral intravenous access only (adjusted odds ratio (aOR) 6.15, 95% confidence interval (CI) 4.58-8.26, p<0.001) and year of admission (aOR 0.74 per year after 2012, 95% CI 0.69-0.80, p<0.001). Other factors that had associations after adjustment included admission to a non-teaching hospital (aOR 2.19, 95% CI 1.23-3.89, p=0.007), admission to a coronary care unit (aOR 2.56, 95% CI 1.001-6.54, p=0.05), SOFA score (aOR 0.92 per unit increase, 95% CI 0.88-0.96, p<0.001) and heart rate (aOR 0.92 per 10 beat per minute increase, 95% CI 0.87-0.97, p=0.002).

CONCLUSIONS

In a large cohort of patients in Alberta, Canada, we found a steady decrease in use of first-line vasopressors other than norepinephrine in septic shock. The strongest factor associated with their use was the presence of only peripheral venous access, suggesting this may still be considered a barrier to administration of norepinephrine.

The Use of Hydrocortisone, Ascorbic Acid and Thiamine in Patients with Sepsis and Septic Shock - A Systematic Review

Background: Sepsis and septic shock are associated with enormous mortality and health care burden. Since the study of Marik et al suggested mortality benefit, there has been great interest in evaluating the role of hydrocortisone, ascorbic acid and thiamine (HAT therapy) in sepsis and septic shock. Purpose: The objective of this article is to review current literature of using HAT therapy in sepsis and septic shock, and discuss the findings in hospital mortality, change in 72 hr SOFA score, other outcomes, and the study limitations. Research Design: Three databases (PubMed, Embase, and Cochrane) were screened using predefined search terms ascorbic acid, vitamin C, thiamine, vitamin B1, hydrocortisone, sepsis, septic shock. Study Sample: Data extracted from eligible studies include authors, publication year, sample size, study design, intervention, outcome measures and study results. Each study was reviewed critically. Results: Among 11 studies included in this literature review, 3 studies reported HAT therapy was associated with mortality benefit, 1 reported hospital mortality was significantly higher in HAT group and the rest of studies didn't reach statistical significance in mortality analysis. Significant improvement of secondary outcomes, although not consistently, were reported. Conclusions: In conclusion, HAT therapy has demonstrated a good safety profile and potential benefits in management of sepsis and septic shock. Further research is required to confirm these findings.

A Standardized Step-by-Step Approach for the Diagnosis and Treatment of Sepsis

Sepsis is the major culprit of death among critically ill patients who are hospitalized in intensive care units (ICUs). Although sepsis-related mortality is steadily declining year-by-year due to the continuous understanding of the pathophysiological mechanism on sepsis and improvement of the bundle treatment, sepsis-associated hospitalization is rising worldwide. Surviving Sepsis Campaign (SSC) guidelines are continuously updating, while their content is extremely complex and comprehensive for a precisely implementation in clinical practice. As a consequence, a standardized step-by-step approach for the diagnosis and treatment of sepsis is particularly important. In the present study, we proposed a standardized step-by-step approach for the diagnosis and treatment of sepsis using our daily clinical experience and the latest researches, which is close to clinical practice and is easy to implement. The proposed approach may assist clinicians to more effectively diagnose and treat septic patients and avoid the emergence of adverse clinical outcomes.

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.

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.

Vitamin C in Critically Ill Patients: An Updated Systematic Review and Meta-Analysis

Background: Vitamin C is a water-soluble antioxidant vitamin. Oxidative stress and its markers, along with inflammatory markers, are high during critical illness. Due to conflicting results of the published literature regarding the efficacy of vitamin C in critically ill patients, and especially the concerns for nephrotoxicity raised by some case reports, this meta-analysis was carried out to appraise the evidence and affirmation regarding the role of vitamin C in critically ill patients. Methods: We searched the database thoroughly to collect relevant studies that assessed intravenous vitamin C use in critically ill patients published until 25 February 2021. We included randomized controlled trials and observational studies with 20 or more critically ill patients who have received intravenous ascorbic acid (vitamin C). After screening 18,312 studies from different databases, 53 were included in our narrative synthesis, and 48 were included in the meta-analysis. We used the Covidence software for screening of the retrieved literature. Review Manager (RevMan) 5.4 was used for the pooling of data and Odds Ratios (OR) and Mean difference (MD) as measures of effects with a 95% confidence interval to assess for explanatory variables. Results: Pooling data from 33 studies for overall hospital mortality outcomes using a random-effect model showed a 19% reduction in odds of mortality among the vitamin C group (OR, 0.81; 95% CI, 0.66–0.98). Length of hospital stay (LOS), mortality at 28/30 days, ICU mortality, new-onset AKI and Renal Replacement Therapy (RRT) for AKI did not differ significantly across the two groups. Analysis of data from 30 studies reporting ICU stay disclosed 0.76 fewer ICU days in the vitamin C group than the placebo/standard of care (SOC) group (95% CI, −1.34 to −0.19). This significance for shortening ICU stay persisted even when considering RCTs only in the analysis (MD, −0.70; 95% CI, −1.39 to −0.02). Conclusion: Treatment of critically ill patients with intravenous vitamin C was relatively safe with no significant difference in adverse renal events and decreased in-hospital mortality. The use of vitamin C showed a significant reduction in the length of ICU stays in critically ill patients.

Therapeutic Approaches in Modulating the Inflammatory and Immunological Response in Patients With Sepsis, Acute Respiratory Distress Syndrome, and Pancreatitis: An Expert Opinion Review

Immunomodulation has long been an adjunct approach in treating critically ill patients with sepsis, acute respiratory distress syndrome (ARDS), and acute pancreatitis (AP). Hyperactive immune response with immunopathogenesis leads to organ dysfunction and alters the clinical outcomes in critically ill. Though the immune response in the critically ill might have been overlooked, it has gathered greater attention during this novel coronavirus disease 2019 (COVID-19) pandemic. Modulating hyperactive immune response, the cytokine storm, especially with steroids, has shown to improve the outcomes in COVID-19 patients. In this review, we find that immune response pathogenesis in critically ill patients with sepsis, ARDS, and AP is nearly similar. The use of immunomodulators such as steroids, broad-spectrum serine protease inhibitors such as ulinastatin, thymosin alpha, intravenous immunoglobulins, and therapies such as CytoSorb and therapeutic plasma exchange may help in improving the clinical outcomes in these conditions. As the experience of the majority of physicians in using such therapeutics may be limited, we provide our expert comments regarding immunomodulation to optimize outcomes in patients with sepsis/septic shock, ARDS, and AP.

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.

Attention to Immortal Time Bias in Critical Care Research

Observational studies in critical care medicine offer a popular and practical approach to questions of treatment effectiveness. Although observational research is widely understood to be susceptible to design and interpretation challenges, one well-described source of bias-immortal time bias (ITB)-is frequently present yet often overlooked. ITB may be introduced by study design oversights or mishandled during data analysis. When present, ITB can create inappropriate estimates of the benefit or harm of an exposure or intervention. Studies examining treatments in critically ill patients may be particularly susceptible to ITB, with consequences for clinical adoption and design and initiation of randomized trials. In this Critical Care Perspective, we illustrate the persistent problem of ITB in observational research using recent studies of hydrocortisone, ascorbic acid, and thiamine therapy in patients with sepsis and septic shock. Of the eight studies examined, none contained enough design or reporting elements to rule out the presence of ITB. To mitigate the influence of ITB in future observational studies, we present a novel checklist to help readers assess the features of study design, analysis, and reporting that introduce ITB or obscure its presence. We recommend that commonly used tools designed to evaluate observational research studies should include an ITB assessment.

Vitamin C for Sepsis and Septic Shock

BACKGROUND

Sepsis remains a leading cause of death in the critically ill. The combination of thiamine, vitamin C, and hydrocortisone has recently emerged as a potential adjunctive therapy and supportive care for patients with sepsis and septic shock.

AREAS OF UNCERTAINTY

Several randomized and observational controlled trials evaluated the role of vitamin C in sepsis and septic shock. However, there are variabilities in the findings of these studies that led to a substantial global debate on incorporating vitamin C therapy in clinical practice.

DATA SOURCES

A PubMed and Embase English language literature search through April 2021 was performed using the following terms: ascorbic acid, vitamin C, corticosteroid, hydrocortisone, thiamine, HAT, sepsis, and shock. Citations, including controlled trials, observational studies, review articles, guidelines, and consensus statements, were reviewed. The risk of bias for each clinical study was systematically evaluated. Relevant clinical data focusing on efficacy, safety, and special considerations regarding the use of vitamin C with and without thiamine and hydrocortisone in sepsis and septic shock were narratively summarized.

RESULTS

The most commonly used vitamin C dosing in sepsis and septic shock is 1.5 g every 6 hours with and without thiamine and hydrocortisone. Current literature is limited because of heterogeneity in vitamin C regimen used, initiation time, and duration of treatment. This limitation led to variability in outcomes evaluated. Vitamin C decreases proinflammatory mediators and slows the progression of endothelial injury in severe sepsis. There is an inconsistency between randomized controlled trials and observational controlled trials regarding mortality, resolution in organ failure, hospital and intensive care unit length of stay findings with the use of vitamin C in septic shock. Vitamin C seems to be safe in comparison with placebo.

CONCLUSIONS

Future studies with consistent end points, initiation time with an emphasis on early initiation, and standard vitamin C dosing regimen are needed to determine the overall benefit of vitamin C in sepsis.

The Efficacy of vitamin C, thiamine, and corticosteroid therapy in adult sepsis patients: a systematic review and meta-analysis

Background

Previous studies have suggested favorable outcomes of hydrocortisone, ascorbic acid (vitamin C), and thiamine (HAT) therapy in patients with sepsis. However, similar results have not been duplicated in sequential studies. This meta-analysis aimed to reevaluate the value of HAT treatment in patients with sepsis.

Methods

Electronic databases were searched up until October 2020 for any studies that compared the effect of HAT versus non-HAT use in patients with sepsis.

Results

Data from 15 studies (eight randomized controlled trials [RCTs] and seven cohort studies) involving 67,349 patients were included. The results from the RCTs show no significant benefit of triple therapy on hospital mortality (risk ratio [RR], 0.99; P=0.92; I2=0%); intensive care unit (ICU) mortality (RR, 0.77; P=0.20; I2=58%); ICU length of stay (weighted mean difference [WMD], 0.11; P=0.86; I2=37%) or hospital length of stay (WMD: 0.57; P=0.49; I2=17%), and renal replacement therapy (RR, 0.64; P=0.44; I2=39%). The delta Sequential Organ Failure Assessment (SOFA) score favored treatment after a sensitivity analysis (WMD, -0.72; P=0.01; I2=32%). However, a significant effect was noted for the duration of vasopressor use (WMD, -25.49; P<0.001; I2=46%). The results from cohort studies have also shown no significant benefit of HAT therapy on hospital mortality, ICU mortality, ICU length of stay, length of hospital stay, the delta SOFA score, the use of renal replacement therapy, or vasopressor duration.

Conclusion

HAT therapy significantly reduced the duration of vasopressor use and improved the SOFA score but appeared not to have significant benefits in other outcomes for patients with sepsis. Further RCTs can help understand its benefit exclusively.

Benefits of combination therapy of hydrocortisone, ascorbic acid and thiamine in sepsis and septic shock: A systematic review

BACKGROUND

Sepsis and septic shock are severe medical conditions that can damage multiple organs with a higher risk of mortality. Recently, the combination of hydrocortisone, ascorbic acid and thiamine (HAT) was hypothesized to work synergistically to reverse septic shock and reduce mortality.

AIM

To ascertain the efficacy of HAT therapy and compare whether HAT therapy is more beneficial compared to the standard of care in sepsis and septic shock patients.

METHODS

PubMed, Clinicaltrials.gov, Scopus, Web of Science, Cochrane and Embase are databases that were used to identify trials that conducted a study of the combination of HAT in sepsis or septic shock.

RESULTS

There were 134 articles identified through a database search and 16 from other sources, which were subsequently reduced to 11 trials (six randomized trials and five non-randomized trials) that were deemed appropriate for inclusion in this review. Most of the outcomes from these studies focused on mortality, the need for renal replacement therapy, duration of vasopressor use, changes in Sequential Organ Failure Assessment score, procalcitonin clearance and lengths of intensive care unit stay.

CONCLUSION

Due to inconsistent results from clinical studies, the benefits of HAT therapy cannot be confirmed at this point in sepsis and septic shock. Currently, there are at least 20 randomized controlled trials testing HAT in various combinations and dosages in patients with severe sepsis and septic shock. The results of these studies are required before definitive conclusions can be made regarding the impact of this novel treatment strategy on the morbidity and mortality of patients with sepsis.

Early experience with critically ill patients with COVID-19 in Montreal

PURPOSE

Montreal has been the epicentre of the coronavirus disease (COVID-19) pandemic in Canada. Given the regional disparities in incidence and mortality in the general population, we aimed to describe local characteristics, treatments, and outcomes of critically ill COVID-19 patients in Montreal.

METHODS

A single-centre retrospective cohort of consecutive adult patients admitted to the intensive care unit (ICU) of Hôpital du Sacré-Coeur de Montréal with confirmed COVID-19 were included.

RESULTS

Between 20 March and 13 May 2020, 75 patients were admitted, with a median [interquartile range (IQR)] age of 62 [53-72] yr and high rates of obesity (47%), hypertension (67%), and diabetes (37%). Healthcare-related infections were responsible for 35% of cases. The median [IQR] day 1 sequential organ failure assessment score was 6 [3-7]. Invasive mechanical ventilation (IMV) was used in 57% of patients for a median [IQR] of 11 [5-22] days. Patients receiving IMV were characterized by a moderately decreased median [IQR] partial pressure of oxygen:fraction of inspired oxygen (day 1 PaO2:FiO2 = 177 [138-276]; day 10 = 173 [147-227]) and compliance (day 1 = 48 [38-58] mL/cmH2O; day 10 = 34 [28-42] mL/cmH2O) and very elevated estimated dead space fraction (day 1 = 0.60 [0.53-0.67]; day 10 = 0.72 [0.69-0.79]). Overall hospital mortality was 25%, and 21% in the IMV patients. Mortality was 82% in patients ≥ 80 yr old.

CONCLUSIONS

Characteristics and outcomes of critically ill patients with COVID-19 in Montreal were similar to those reported in the existing literature. We found an increased physiologic dead space, supporting the hypothesis that pulmonary vascular injury may be central to COVID-19-induced lung damage.