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1.
Antioxidants (Basel) ; 13(1)2024 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-38247519

RESUMO

Acute respiratory distress syndrome (ARDS) is a life-threatening event that occurs in patients suffering from bacterial, fungal, or viral sepsis. Research performed over the last five decades showed that ARDS is a consequence of severe unrestrained systemic inflammation, which leads to injury of the lung's microvasculature and alveolar epithelium. ARDS leads to acute hypoxic/hypercapnic respiratory failure and death in a significant number of patients hospitalized in intensive care units worldwide. Basic and clinical research performed during the time since ARDS was first described has been unable to construct a pharmacological agent that will combat the inflammatory fire leading to ARDS. In-depth studies of the molecular pharmacology of vitamin C indicate that it can serve as a potent anti-inflammatory agent capable of attenuating the pathobiological events that lead to acute injury of the lungs and other body organs. This analysis of vitamin C's role in the treatment of ARDS includes a focused systematic review of the literature relevant to the molecular physiology of vitamin C and to the past performance of clinical trials using the agent.

2.
Nutrients ; 14(20)2022 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-36297099

RESUMO

(1) Background: The disease-modifying mechanisms of high-dose intravenous vitamin C (HDIVC) in sepsis induced acute respiratory distress syndrome (ARDS) is unclear. (2) Methods: We performed a post hoc study of plasma biomarkers from subjects enrolled in the randomized placebo-controlled trial CITRIS-ALI. We explored the effects of HDIVC on cell-free DNA (cfDNA) and syndecan-1, surrogates for neutrophil extracellular trap (NET) formation and degradation of the endothelial glycocalyx, respectively. (3) Results: In 167 study subjects, baseline cfDNA levels in HDIVC (84 subjects) and placebo (83 subjects) were 2.18 ng/µL (SD 4.20 ng/µL) and 2.65 ng/µL (SD 3.87 ng/µL), respectively, p = 0.45. At 48-h, the cfDNA reduction was 1.02 ng/µL greater in HDIVC than placebo, p = 0.05. Mean baseline syndecan-1 levels in HDIVC and placebo were 9.49 ng/mL (SD 5.57 ng/mL) and 10.83 ng/mL (SD 5.95 ng/mL), respectively, p = 0.14. At 48 h, placebo subjects exhibited a 1.53 ng/mL (95% CI, 0.96 to 2.11) increase in syndecan-1 vs. 0.75 ng/mL (95% CI, 0.21 to 1.29, p = 0.05), in HDIVC subjects. (4) Conclusions: HDIVC infusion attenuated cell-free DNA and syndecan-1, biomarkers associated with sepsis-induced ARDS. Improvement of these biomarkers suggests amelioration of NETosis and shedding of the vascular endothelial glycocalyx, respectively.


Assuntos
Ácidos Nucleicos Livres , Armadilhas Extracelulares , Síndrome do Desconforto Respiratório , Sepse , Humanos , Glicocálix , Sindecana-1/metabolismo , Sindecana-1/farmacologia , Ácido Ascórbico/uso terapêutico , Sepse/complicações , Sepse/tratamento farmacológico , Sepse/metabolismo , Síndrome do Desconforto Respiratório/tratamento farmacológico , Síndrome do Desconforto Respiratório/etiologia , Vitaminas/uso terapêutico , Biomarcadores
3.
Lancet Respir Med ; 10(9): 916-924, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36057279

RESUMO

The acute respiratory distress syndrome (ARDS) is a common critical illness syndrome with high morbidity and mortality. There are no proven pharmacological therapies for ARDS. The current definition of ARDS is based on shared clinical characteristics but does not capture the heterogeneity in clinical risk factors, imaging characteristics, physiology, timing of onset and trajectory, and biology of the syndrome. There is increasing interest within the ARDS clinical trialist community to design clinical trials that reduce heterogeneity in the trial population. This effort must be balanced with ongoing work to craft an inclusive, global definition of ARDS, with important implications for trial design. Ultimately, the two aims-to design trials that are applicable to the diverse global ARDS population while also advancing opportunities to identify targetable traits-should coexist. In this Personal View, we recommend two primary strategies to improve future ARDS trials: the development of new methods to target treatable traits in clinical trial populations, and improvements in the representativeness of ARDS trials, with the inclusion of global populations. We emphasise that these two strategies are complementary. We also discuss how a proposed expansion of the definition of ARDS could affect the future of clinical trials.


Assuntos
Síndrome do Desconforto Respiratório , Ensaios Clínicos como Assunto , Humanos , Fenótipo , Síndrome do Desconforto Respiratório/terapia , Fatores de Risco
4.
Nutrients ; 13(10)2021 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-34684565

RESUMO

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.


Assuntos
Ácido Ascórbico/farmacologia , Estado Terminal , Injúria Renal Aguda/terapia , Ensaios Clínicos como Assunto , Estado Terminal/mortalidade , Mortalidade Hospitalar , Humanos , Unidades de Terapia Intensiva , Tempo de Internação , Terapia de Substituição Renal
5.
JAMA ; 325(8): 742-750, 2021 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-33620405

RESUMO

Importance: Sepsis is a common syndrome with substantial morbidity and mortality. A combination of vitamin C, thiamine, and corticosteroids has been proposed as a potential treatment for patients with sepsis. Objective: To determine whether a combination of vitamin C, thiamine, and hydrocortisone every 6 hours increases ventilator- and vasopressor-free days compared with placebo in patients with sepsis. Design, Setting, and Participants: Multicenter, randomized, double-blind, adaptive-sample-size, placebo-controlled trial conducted in adult patients with sepsis-induced respiratory and/or cardiovascular dysfunction. Participants were enrolled in the emergency departments or intensive care units at 43 hospitals in the United States between August 2018 and July 2019. After enrollment of 501 participants, funding was withheld, leading to an administrative termination of the trial. All study-related follow-up was completed by January 2020. Interventions: Participants were randomized to receive intravenous vitamin C (1.5 g), thiamine (100 mg), and hydrocortisone (50 mg) every 6 hours (n = 252) or matching placebo (n = 249) for 96 hours or until discharge from the intensive care unit or death. Participants could be treated with open-label corticosteroids by the clinical team, with study hydrocortisone or matching placebo withheld if the total daily dose was greater or equal to the equivalent of 200 mg of hydrocortisone. Main Outcomes and Measures: The primary outcome was the number of consecutive ventilator- and vasopressor-free days in the first 30 days following the day of randomization. The key secondary outcome was 30-day mortality. Results: Among 501 participants randomized (median age, 62 [interquartile range {IQR}, 50-70] years; 46% female; 30% Black; median Acute Physiology and Chronic Health Evaluation II score, 27 [IQR, 20.8-33.0]; median Sequential Organ Failure Assessment score, 9 [IQR, 7-12]), all completed the trial. Open-label corticosteroids were prescribed to 33% and 32% of the intervention and control groups, respectively. Ventilator- and vasopressor-free days were a median of 25 days (IQR, 0-29 days) in the intervention group and 26 days (IQR, 0-28 days) in the placebo group, with a median difference of -1 day (95% CI, -4 to 2 days; P = .85). Thirty-day mortality was 22% in the intervention group and 24% in the placebo group. Conclusions and Relevance: Among critically ill patients with sepsis, treatment with vitamin C, thiamine, and hydrocortisone, compared with placebo, did not significantly increase ventilator- and vasopressor-free days within 30 days. However, the trial was terminated early for administrative reasons and may have been underpowered to detect a clinically important difference. Trial Registration: ClinicalTrials.gov Identifier: NCT03509350.


Assuntos
Anti-Inflamatórios/uso terapêutico , Ácido Ascórbico/uso terapêutico , Hidrocortisona/uso terapêutico , Respiração Artificial , Sepse/tratamento farmacológico , Tiamina/uso terapêutico , Vitaminas/uso terapêutico , Adulto , Idoso , Estado Terminal , Método Duplo-Cego , Quimioterapia Combinada , Término Precoce de Ensaios Clínicos , Feminino , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Escores de Disfunção Orgânica , Insuficiência Respiratória/etiologia , Insuficiência Respiratória/terapia , Sepse/complicações , Sepse/mortalidade , Sepse/terapia , Resultado do Tratamento , Vasoconstritores/uso terapêutico
8.
Nutrients ; 12(2)2020 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-31978969

RESUMO

Sepsis, a life-threatening organ dysfunction due to a dysregulated host response to infection, is a leading cause of morbidity and mortality worldwide. Decades of research have failed to identify any specific therapeutic targets outside of antibiotics, infectious source elimination, and supportive care. More recently, vitamin C has emerged as a potential therapeutic agent to treat sepsis. Vitamin C has been shown to be deficient in septic patients and the administration of high dose intravenous as opposed to oral vitamin C leads to markedly improved and elevated serum levels. Its physiologic role in sepsis includes attenuating oxidative stress and inflammation, improving vasopressor synthesis, enhancing immune cell function, improving endovascular function, and epigenetic immunologic modifications. Multiple clinical trials have demonstrated the safety of vitamin C and two recent studies have shown promising data on mortality improvement. Currently, larger randomized controlled studies are underway to validate these findings. With further study, vitamin C may become standard of care for the treatment of sepsis, but given its safety profile, current treatment can be justified with compassionate use.


Assuntos
Ácido Ascórbico/uso terapêutico , Sepse/tratamento farmacológico , Vitaminas/uso terapêutico , Administração Intravenosa , Humanos
9.
Trials ; 20(1): 670, 2019 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-31801567

RESUMO

BACKGROUND: Observational research suggests that combined therapy with Vitamin C, thiamine and hydrocortisone may reduce mortality in patients with septic shock. METHODS AND DESIGN: The Vitamin C, Thiamine and Steroids in Sepsis (VICTAS) trial is a multicenter, double-blind, adaptive sample size, randomized, placebo-controlled trial designed to test the efficacy of combination therapy with vitamin C (1.5 g), thiamine (100 mg), and hydrocortisone (50 mg) given every 6 h for up to 16 doses in patients with respiratory or circulatory dysfunction (or both) resulting from sepsis. The primary outcome is ventilator- and vasopressor-free days with mortality as the key secondary outcome. Recruitment began in August 2018 and is ongoing; 501 participants have been enrolled to date, with a planned maximum sample size of 2000. The Data and Safety Monitoring Board reviewed interim results at N = 200, 300, 400 and 500, and has recommended continuing recruitment. The next interim analysis will occur when N = 1000. This update presents the statistical analysis plan. Specifically, we provide definitions for key treatment and outcome variables, and for intent-to-treat, per-protocol, and safety analysis datasets. We describe the planned descriptive analyses, the main analysis of the primary end point, our approach to secondary and exploratory analyses, and handling of missing data. Our goal is to provide enough detail that our approach could be replicated by an independent study group, thereby enhancing the transparency of the study. TRIAL REGISTRATION: ClinicalTrials.gov, NCT03509350. Registered on 26 April 2018.


Assuntos
Ácido Ascórbico/administração & dosagem , Interpretação Estatística de Dados , Hidrocortisona/administração & dosagem , Ensaios Clínicos Controlados Aleatórios como Assunto , Tamanho da Amostra , Sepse/tratamento farmacológico , Tiamina/administração & dosagem , Método Duplo-Cego , Quimioterapia Combinada , Humanos , Estudos Prospectivos , Projetos de Pesquisa
10.
JAMA ; 322(13): 1261-1270, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31573637

RESUMO

Importance: Experimental data suggest that intravenous vitamin C may attenuate inflammation and vascular injury associated with sepsis and acute respiratory distress syndrome (ARDS). Objective: To determine the effect of intravenous vitamin C infusion on organ failure scores and biological markers of inflammation and vascular injury in patients with sepsis and ARDS. Design, Setting, and Participants: The CITRIS-ALI trial was a randomized, double-blind, placebo-controlled, multicenter trial conducted in 7 medical intensive care units in the United States, enrolling patients (N = 167) with sepsis and ARDS present for less than 24 hours. The study was conducted from September 2014 to November 2017, and final follow-up was January 2018. Interventions: Patients were randomly assigned to receive intravenous infusion of vitamin C (50 mg/kg in dextrose 5% in water, n = 84) or placebo (dextrose 5% in water only, n = 83) every 6 hours for 96 hours. Main Outcomes and Measures: The primary outcomes were change in organ failure as assessed by a modified Sequential Organ Failure Assessment score (range, 0-20, with higher scores indicating more dysfunction) from baseline to 96 hours, and plasma biomarkers of inflammation (C-reactive protein levels) and vascular injury (thrombomodulin levels) measured at 0, 48, 96, and 168 hours. Results: Among 167 randomized patients (mean [SD] age, 54.8 years [16.7]; 90 men [54%]), 103 (62%) completed the study to day 60. There were no significant differences between the vitamin C and placebo groups in the primary end points of change in mean modified Sequential Organ Failure Assessment score from baseline to 96 hours (from 9.8 to 6.8 in the vitamin C group [3 points] and from 10.3 to 6.8 in the placebo group [3.5 points]; difference, -0.10; 95% CI, -1.23 to 1.03; P = .86) or in C-reactive protein levels (54.1 vs 46.1 µg/mL; difference, 7.94 µg/mL; 95% CI, -8.2 to 24.11; P = .33) and thrombomodulin levels (14.5 vs 13.8 ng/mL; difference, 0.69 ng/mL; 95% CI, -2.8 to 4.2; P = .70) at 168 hours. Conclusions and Relevance: In this preliminary study of patients with sepsis and ARDS, a 96-hour infusion of vitamin C compared with placebo did not significantly improve organ dysfunction scores or alter markers of inflammation and vascular injury. Further research is needed to evaluate the potential role of vitamin C for other outcomes in sepsis and ARDS. Trial Registration: ClinicalTrials.gov Identifier: NCT02106975.


Assuntos
Ácido Ascórbico/administração & dosagem , Insuficiência de Múltiplos Órgãos/prevenção & controle , Síndrome do Desconforto Respiratório/tratamento farmacológico , Sepse/tratamento farmacológico , Vitaminas/administração & dosagem , Adulto , Idoso , Ácido Ascórbico/uso terapêutico , Biomarcadores/sangue , Proteína C-Reativa/análise , Método Duplo-Cego , Feminino , Humanos , Infusões Intravenosas , Unidades de Terapia Intensiva , Masculino , Pessoa de Meia-Idade , Insuficiência de Múltiplos Órgãos/etiologia , Escores de Disfunção Orgânica , Síndrome do Desconforto Respiratório/complicações , Síndrome do Desconforto Respiratório/mortalidade , Sepse/complicações , Sepse/mortalidade , Trombomodulina/sangue , Vitaminas/uso terapêutico
11.
J Thromb Haemost ; 17(11): 1827-1837, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31322812

RESUMO

BACKGROUND: Fluid resuscitation plays a prominent role in stabilizing trauma patients with hemorrhagic shock yet there remains uncertainty with regard to optimal administration time, volume, and fluid composition (e.g., whole blood, component, colloids) leading to complications such as trauma-induced coagulopathies (TIC), acidosis, and poor oxygen transport. Synthetic fluids in combination with antioxidants (e.g., vitamin C) may resolve some of these problems. OBJECTIVES: We applied quantitative mass spectrometry-based proteomics [liquid chromatography-mass spectrometry (LC-MS/MS)] to map the effects of fluid resuscitation and intravenous vitamin C (VitC) in a pig model of polytrauma (hemorrhagic shock, tissue injury, liver reperfusion, hypothermia, and comminuted bone fracture). The goal was to determine the effects of VitC on plasma protein expression, with respect to changes associated with coagulation and trauma-induced coagulopathy (TIC). METHODS: Longitudinal blood samples were drawn from nine male Sinclair pigs at baseline, 2 h post trauma, and 0.25, 2, and 4 h post fluid resuscitation with 500 mL hydroxyethyl starch. Pigs were treated intravenously (N = 3/treatment group) with saline, 50 mg VitC/kg (Lo-VitC), or 200 mg VitC/kg (Hi-VitC) during fluid resuscitation. RESULTS: A total of 436 plasma proteins were quantified of which 136 changed following trauma and resuscitation; 34 were associated with coagulation, complement cascade, and glycolysis. Unexpectedly, Lo-VitC and Hi-VitC treatments stabilized ADAMTS13 levels by ~4-fold (P = .056) relative to saline and enhanced ADAMTS13/von Willebrand factor (VWF) cleavage efficiency based on LC-MS/MS evidence for the semitryptic VWF cleavage product (VWF1275-1286 ). CONCLUSIONS: This study provides the first comprehensive map of trauma-induced changes to the plasma proteome, especially with respect to proteins driving the development of TIC.


Assuntos
Antioxidantes/administração & dosagem , Ácido Ascórbico/administração & dosagem , Coagulação Sanguínea , Proteínas Sanguíneas/metabolismo , Hidratação , Traumatismo Múltiplo/terapia , Ressuscitação , Choque Hemorrágico/terapia , Administração Intravenosa , Animais , Biomarcadores/sangue , Cromatografia Líquida , Modelos Animais de Doenças , Masculino , Traumatismo Múltiplo/sangue , Proteômica , Choque Hemorrágico/sangue , Sus scrofa , Espectrometria de Massas em Tandem , Fatores de Tempo
12.
Crit Care Med ; 47(10): 1388-1395, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31343474

RESUMO

OBJECTIVES: There is mounting evidence that delays in appropriate antimicrobial administration are responsible for preventable deaths in patients with sepsis. Herein, we examine the association between potentially modifiable antimicrobial administration delays, measured by the time from the first order to the first administration (antimicrobial lead time), and death among people who present with new onset of sepsis. DESIGN: Observational cohort and case-control study. SETTING: The emergency department of an academic, tertiary referral center during a 3.5-year period. PATIENTS: Adult patients with new onset of sepsis or septic shock. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: We enrolled 4,429 consecutive patients who presented to the emergency department with a new diagnosis of sepsis. We defined 0-1 hour as the gold standard antimicrobial lead time for comparison. Fifty percent of patients had an antimicrobial lead time of more than 1.3 hours. For an antimicrobial lead time of 1-2 hours, the adjusted odds ratio of death at 28 days was 1.28 (95% CI, 1.07-1.54; p = 0.007); for an antimicrobial lead time of 2-3 hours was 1.07 (95% CI, 0.85-1.36; p = 0.6); for an antimicrobial lead time of 3-6 hours was 1.57 (95% CI, 1.26-1.95; p < 0.001); for an antimicrobial lead time of 6-12 hours was 1.36 (95% CI, 0.99-1.86; p = 0.06); and for an antimicrobial lead time of more than 12 hours was 1.85 (95% CI, 1.29-2.65; p = 0.001). CONCLUSIONS: Delays in the first antimicrobial execution, after the initial clinician assessment and first antimicrobial order, are frequent and detrimental. Biases inherent to the retrospective nature of the study apply. Known biologic mechanisms support these findings, which also demonstrate a dose-response effect. In contrast to the elusive nature of sepsis onset and sepsis onset recognition, antimicrobial lead time is an objective, measurable, and modifiable process.


Assuntos
Anti-Infecciosos/provisão & distribuição , Anti-Infecciosos/uso terapêutico , Sepse/tratamento farmacológico , Sepse/mortalidade , Tempo para o Tratamento , Estudos de Casos e Controles , Estudos de Coortes , Humanos , Estudos Retrospectivos
13.
Eur J Haematol ; 103(2): 134-136, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31140644

RESUMO

Checkpoint inhibitor therapy is effective in the treatment of relapsed classical Hodgkin's Lymphoma. Here, we report a patient with relapsed Hodgkin's Lymphoma who received nivolumab prior to autologous stem cell mobilization. She went on to develop cytokine storm shortly following transplantation, with marked T-cell proliferation coincident with myeloid engraftment. Non-cardiogenic pulmonary edema and alveolar hemorrhage developed despite corticosteroid therapy. There was rapid and complete resolution of these complications with parenteral ascorbic acid infusion. Our case illustrates the risk of cytokine release syndrome following infusion of stem cells mobilized after checkpoint inhibitor therapy and the role of ascorbic acid in its management.


Assuntos
Antineoplásicos Imunológicos/uso terapêutico , Mobilização de Células-Tronco Hematopoéticas , Doença de Hodgkin/complicações , Doença de Hodgkin/terapia , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Adulto , Antineoplásicos Imunológicos/administração & dosagem , Antineoplásicos Imunológicos/efeitos adversos , Ácido Ascórbico/administração & dosagem , Síndrome da Liberação de Citocina/diagnóstico , Síndrome da Liberação de Citocina/tratamento farmacológico , Síndrome da Liberação de Citocina/etiologia , Gerenciamento Clínico , Feminino , Mobilização de Células-Tronco Hematopoéticas/métodos , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Transplante de Células-Tronco Hematopoéticas/métodos , Doença de Hodgkin/diagnóstico , Humanos , Imuno-Histoquímica , Imunofenotipagem , Estadiamento de Neoplasias , Tomografia Computadorizada por Raios X , Condicionamento Pré-Transplante
14.
Trials ; 20(1): 197, 2019 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-30953543

RESUMO

BACKGROUND: Sepsis accounts for 30% to 50% of all in-hospital deaths in the United States. Other than antibiotics and source control, management strategies are largely supportive with fluid resuscitation and respiratory, renal, and circulatory support. Intravenous vitamin C in conjunction with thiamine and hydrocortisone has recently been suggested to improve outcomes in patients with sepsis in a single-center before-and-after study. However, before this therapeutic strategy is adopted, a rigorous assessment of its efficacy is needed. METHODS: The Vitamin C, Thiamine and Steroids in Sepsis (VICTAS) trial is a prospective, multi-center, double-blind, adaptive sample size, randomized, placebo-controlled trial. It will enroll patients with sepsis causing respiratory or circulatory compromise or both. Patients will be randomly assigned (1:1) to receive intravenous vitamin C (1.5 g), thiamine (100 mg), and hydrocortisone (50 mg) every 6 h or matching placebos until a total of 16 administrations have been completed or intensive care unit discharge occurs (whichever is first). Patients randomly assigned to the comparator group are permitted to receive open-label stress-dose steroids at the discretion of the treating clinical team. The primary outcome is consecutive days free of ventilator and vasopressor support (VVFDs) in the 30 days following randomization. The key secondary outcome is mortality at 30 days. Sample size will be determined adaptively by using interim analyses with pre-stated stopping rules to allow the early recognition of a large mortality benefit if one exists and to refocus on the more sensitive outcome of VVFDs if an early large mortality benefit is not observed. DISCUSSION: VICTAS is a large, multi-center, double-blind, adaptive sample size, randomized, placebo-controlled trial that will test the efficacy of vitamin C, thiamine, and hydrocortisone as a combined therapy in patients with respiratory or circulatory dysfunction (or both) resulting from sepsis. Because the components of this therapy are inexpensive and readily available and have very favorable risk profiles, demonstrated efficacy would have immediate implications for the management of sepsis worldwide. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT03509350 . First registered on April 26, 2018, and last verified on December 20, 2018. Protocol version: 1.4, January 9, 2019.


Assuntos
Ácido Ascórbico/administração & dosagem , Hidrocortisona/administração & dosagem , Sepse/tratamento farmacológico , Tiamina/administração & dosagem , Administração Intravenosa , Ácido Ascórbico/efeitos adversos , Método Duplo-Cego , Esquema de Medicação , Quimioterapia Combinada , Mortalidade Hospitalar , Humanos , Hidrocortisona/efeitos adversos , Estudos Multicêntricos como Assunto , Estudos Prospectivos , Ensaios Clínicos Controlados Aleatórios como Assunto , Tamanho da Amostra , Sepse/diagnóstico , Sepse/mortalidade , Sepse/fisiopatologia , Tiamina/efeitos adversos , Fatores de Tempo , Resultado do Tratamento , Estados Unidos
15.
J Trauma Acute Care Surg ; 85(1S Suppl 2): S57-S67, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29538225

RESUMO

BACKGROUND: Coagulopathy and inflammation induced by hemorrhagic shock and traumatic injury are associated with increased mortality and morbidity. Vitamin C (VitC) is an antioxidant with potential protective effects on the proinflammatory and procoagulant pathways. We hypothesized that high-dose VitC administered as a supplement to fluid resuscitation would attenuate inflammation, coagulation dysfunction, and end-organ tissue damage in a swine model of multiple injuries and hemorrhage. METHODS: Male Sinclair swine (n = 24; mean body weight, 27 kg) were anesthetized, intubated, mechanically ventilated, and instrumented for physiologic monitoring. Following stabilization, swine were subjected to shock/traumatic injury (hypothermia, liver ischemia and reperfusion, comminuted femur fracture, hemorrhagic hypotension), resuscitated with 500 mL of hydroxyethyl starch, and randomized to receive either intravenous normal saline (NS), low-dose VitC (50 mg/kg; LO), or high-dose VitC (200 mg/kg; HI). Hemodynamics, blood chemistry, hematology, and coagulation function (ROTEM) were monitored to 4 hours postresuscitation. Histological and molecular analyses were obtained for liver, kidney, and lung. RESULTS: Compared with VitC animals, NS swine showed significant histological end-organ damage, elevated acute lung injury scores, and increased mRNA expression of tissue proinflammatory mediators (IL-1ß, IL-8, TNFα), plasminogen activation inhibitor-1 and tissue factor. There were no statistically significant differences between treatment groups on mean arterial pressure or univariate measures of coagulation function; however, NS showed impaired multivariate clotting function at 4 hours. CONCLUSION: Although correction of coagulation dysfunction was modest, intravenous high-dose VitC may mitigate the proinflammatory/procoagulant response that contributes to multiple organ failure following acute severe multiple injuries. LEVEL OF EVIDENCE: Prospective randomized controlled blinded trial study, Preclinical (animal-based).


Assuntos
Ácido Ascórbico , Transtornos da Coagulação Sanguínea , Inflamação , Traumatismo Múltiplo , Animais , Masculino , Anti-Inflamatórios/administração & dosagem , Anti-Inflamatórios/uso terapêutico , Anticoagulantes/administração & dosagem , Anticoagulantes/uso terapêutico , Ácido Ascórbico/administração & dosagem , Ácido Ascórbico/uso terapêutico , Transtornos da Coagulação Sanguínea/tratamento farmacológico , Transtornos da Coagulação Sanguínea/etiologia , Modelos Animais de Doenças , Inflamação/tratamento farmacológico , Inflamação/etiologia , Traumatismo Múltiplo/complicações , Traumatismo Múltiplo/terapia , Distribuição Aleatória , Ressuscitação/métodos , Choque Hemorrágico/etiologia , Choque Hemorrágico/terapia , Suínos
16.
Antioxidants (Basel) ; 6(3)2017 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-28704937

RESUMO

Stored red blood cells (RBCs) undergo oxidative stress that induces deleterious metabolic, structural, biochemical, and molecular changes collectively referred to as "storage lesions". We hypothesized that vitamin C (VitC, reduced or oxidized) would reduce red cell storage lesions, thus prolonging their storage duration. Whole-blood-derived, leuko-reduced, SAGM (saline-adenine-glucose-mannitol)-preserved RBC concentrates were equally divided into four pediatric storage bags and the following additions made: (1) saline (saline); (2) 0.3 mmol/L reduced VitC (Lo VitC); (3) 3 mmol/L reduced VitC (Hi VitC); or (4) 0.3 mmol/L oxidized VitC (dehydroascorbic acid, DHA) as final concentrations. Biochemical and rheological parameters were serially assessed at baseline (prior to supplementation) and Days 7, 21, 42, and 56 for RBC VitC concentration, pH, osmotic fragility by mechanical fragility index, and percent hemolysis, LDH release, glutathione depletion, RBC membrane integrity by scanning electron microscopy, and Western blot for ß-spectrin. VitC exposure (reduced and oxidized) significantly increased RBC antioxidant status with varying dynamics and produced trends in reduction in osmotic fragility and increases in membrane integrity. CONCLUSION: VitC partially protects RBC from oxidative changes during storage. Combining VitC with other antioxidants has the potential to improve long-term storage of RBC.

17.
Case Rep Crit Care ; 2016: 8560871, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27891260

RESUMO

This case report summarizes the first use of intravenous vitamin C employed as an adjunctive interventional agent in the therapy of recurrent acute respiratory distress syndrome (ARDS). The two episodes of ARDS occurred in a young female patient with Cronkhite-Canada syndrome, a rare, sporadically occurring, noninherited disorder that is characterized by extensive gastrointestinal polyposis and malabsorption. Prior to the episodes of sepsis, the patient was receiving nutrition via chronic hyperalimentation administered through a long-standing central venous catheter. The patient became recurrently septic with Gram positive cocci which led to two instances of ARDS. This report describes the broad-based general critical care of a septic patient with acute respiratory failure that includes fluid resuscitation, broad-spectrum antibiotics, and vasopressor support. Intravenous vitamin C infused at 50 mg per kilogram body weight every 6 hours for 96 hours was incorporated as an adjunctive agent in the care of this patient. Vitamin C when used as a parenteral agent in high doses acts "pleiotropically" to attenuate proinflammatory mediator expression, to improve alveolar fluid clearance, and to act as an antioxidant.

18.
Exp Gerontol ; 81: 101-9, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27188767

RESUMO

BACKGROUND: Approximately 800 thousand patients require mechanical ventilation in the United States annually with an in-hospital mortality rate of over 30%. The majority of patients requiring mechanical ventilation are over the age of 65 and advanced age is known to increase the severity of ventilator-induced lung injury (VILI) and in-hospital mortality rates. However, the mechanisms which predispose aging ventilator patients to increased mortality rates are not fully understood. Ventilation with conservative fluid management decreases mortality rates in acute respiratory distress patients, but to date there has been no investigation of the effect of conservative fluid management on VILI and ventilator associated mortality rates. We hypothesized that age-associated increases in susceptibility and incidence of pulmonary edema strongly promote age-related increases in ventilator associated mortality. METHODS: 2month old and 20month old male C57BL6 mice were mechanically ventilated with either high tidal volume (HVT) or low tidal volume (LVT) for up to 4h with either liberal or conservative fluid support. During ventilation, lung compliance, total lung capacity, and hysteresis curves were quantified. Following ventilation, bronchoalveolar lavage fluid was analyzed for total protein content and inflammatory cell infiltration. Wet to dry ratios were used to directly measure edema in excised lungs. Lung histology was performed to quantify alveolar barrier damage/destruction. Age matched non-ventilated mice were used as controls. RESULTS: At 4h, both advanced age and HVT ventilation significantly increased markers of inflammation and injury, degraded pulmonary mechanics, and decreased survival rates. Conservative fluid support significantly diminished pulmonary edema and improved pulmonary mechanics by 1h in advanced age HVT subjects. In 4h ventilations, conservative fluid support significantly diminished pulmonary edema, improved lung mechanics, and resulted in significantly lower mortality rates in older subjects. CONCLUSION: Our study demonstrates that conservative fluid alone can attenuate the age associated increase in ventilator associated mortality.


Assuntos
Envelhecimento , Hidratação/métodos , Pulmão/patologia , Lesão Pulmonar Induzida por Ventilação Mecânica/terapia , Animais , Líquido da Lavagem Broncoalveolar/química , Líquido da Lavagem Broncoalveolar/citologia , Inflamação/patologia , Estimativa de Kaplan-Meier , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Volume de Ventilação Pulmonar , Lesão Pulmonar Induzida por Ventilação Mecânica/mortalidade , Lesão Pulmonar Induzida por Ventilação Mecânica/patologia
19.
Int Wound J ; 13(4): 572-84, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26290474

RESUMO

Vitamin C (VitC) or ascorbic acid (AscA), a cofactor for collagen synthesis and a primary antioxidant, is rapidly consumed post-wounding. Parenteral VitC administration suppresses pro-inflammatory responses while promoting anti-inflammatory and pro-resolution effects in human/murine sepsis. We hypothesised that VitC could promote wound healing by altering the inflammatory, proliferative and remodelling phases of wound healing. Mice unable to synthesise VitC (Gulo(-/-) ) were used in this study. VitC was provided in the water (sufficient), withheld from another group (deficient) and supplemented by daily intra-peritoneal infusion (200 mg/kg, deficient + AscA) in a third group. Full thickness excisional wounds (6 mm) were created and tissue collected on days 7 and 14 for histology, quantitative polymerase chain reaction (qPCR) and Western blotting. Human neonatal dermal fibroblasts (HnDFs) were used to assess effects of In conclusion, VitC favorably on proliferation. Histological analysis showed improved wound matrix deposition and organisation in sufficient and deficient +AscA mice. Wounds from VitC sufficient and deficient + AscA mice had reduced expression of pro-inflammatory mediators and higher expression of wound healing mediators. Supplementation of HnDF with AscA induced the expression of self-renewal genes and promoted fibroblast proliferation. VitC favourably impacts the spatiotemporal expression of transcripts associated with early resolution of inflammation and tissue remodelling.


Assuntos
Cicatrização , Animais , Antioxidantes , Ácido Ascórbico , Fibroblastos , Humanos , Inflamação , Camundongos
20.
Crit Care ; 19: 418, 2015 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-26612352

RESUMO

Severe systemic inflammatory response to infection results in severe sepsis and septic shock, which are the leading causes of death in critically ill patients. Septic shock is characterised by refractory hypotension and is typically managed by fluid resuscitation and administration of catecholamine vasopressors such as norepinephrine. Vasopressin can also be administered to raise mean arterial pressure or decrease the norepinephrine dose. Endogenous norepinephrine and vasopressin are synthesised by the copper-containing enzymes dopamine ß-hydroxylase and peptidylglycine α-amidating monooxygenase, respectively. Both of these enzymes require ascorbate as a cofactor for optimal activity. Patients with severe sepsis present with hypovitaminosis C, and pre-clinical and clinical studies have indicated that administration of high-dose ascorbate decreases the levels of pro-inflammatory biomarkers, attenuates organ dysfunction and improves haemodynamic parameters. It is conceivable that administration of ascorbate to septic patients with hypovitaminosis C could improve endogenous vasopressor synthesis and thus ameliorate the requirement for exogenously administered vasopressors. Ascorbate-dependent vasopressor synthesis represents a currently underexplored biochemical mechanism by which ascorbate could act as an adjuvant therapy for severe sepsis and septic shock.


Assuntos
Arginina Vasopressina/uso terapêutico , Ácido Ascórbico/uso terapêutico , Norepinefrina/biossíntese , Sepse/tratamento farmacológico , Choque Séptico/tratamento farmacológico , Vasopressinas/biossíntese , Ácido Ascórbico/administração & dosagem , Hemodinâmica , Humanos , Norepinefrina/uso terapêutico , Vasoconstritores/uso terapêutico , Vasopressinas/uso terapêutico
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