Publications by authors named "Natanson C"

A "restrictive" red blood cell transfusion threshold, a hemoglobin concentration <7 to 8 g/dL, has long been recommended for most hospitalized patients including anemic patients with stable cardiovascular disease (CVD). Although no threshold recommendation is given for acute coronary syndromes (ACSs), recent evidence suggests that "liberal" rather than "restrictive" transfusion strategies are associated with significantly improved safety for hospitalized patients with stable CVD and/or ACS. This finding suggests that previously available data were misinterpreted.

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  • Septic shock leads to increased end-diastolic volume (EDV) and decreased ejection fraction in survivors, unlike nonsurvivors, whose EDV does not increase due to more severe diastolic dysfunction early in the condition.* -
  • In a study with beagles, findings indicate that septic animals experienced significant heart issues, including wall edema and thinning, resulting in decreased heart performance, particularly in nonsurvivors during the initial phase of sepsis.* -
  • The research suggests that cardiac dysfunction during sepsis is connected to microvascular injury and edema, with important implications for understanding heart changes and recovery in septic patients.*
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  • * Beagles were given either saline or epinephrine infusions, with results indicating that while epinephrine significantly increased plasma levels, it did not worsen heart function compared to saline.
  • * The findings suggest that heart dysfunction in sepsis is not mainly caused by high levels of catecholamines, but also highlight changes in microcirculatory perfusion and heart function variability between treated and untreated groups.
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  • Septic shock causes significant cardiac dysfunction in both humans and animal models, characterized by increased biventricular end diastolic volume and decreased ejection fraction, with these abnormalities developing over the course of two days and generally reversing by day ten.
  • In a study involving purpose-bred beagles, septic animals showed greater left ventricular wall edema and dysfunction compared to controls, with non-survivors displaying more severe changes in cardiac function and size.
  • The differential changes in cardiac volume and function between survivors and non-survivors suggest that septic shock impacts heart performance significantly, but the exact mechanisms behind these differences remain unclear.
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To determine whether contemporaneous practices are adequately represented in recent critical care comparative effectiveness research studies. All critical care comparative effectiveness research trials published in the from April 2019 to March 2020 were identified. To examine studies published in other high impact medical journals during the same period, such trials were subsequently also identified in the and All cited sources were reviewed, and the medical literature was searched to find studies describing contemporary practices.

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Background: Comparative effectiveness research is meant to determine which commonly employed medical interventions are most beneficial, least harmful, and/or most costly in a real-world setting. While the objectives for comparative effectiveness research are clear, the field has failed to develop either a uniform definition of comparative effectiveness research or an appropriate set of recommendations to provide standards for the design of critical care comparative effectiveness research trials, spurring controversy in recent years. The insertion of non-representative control and/or comparator arm subjects into critical care comparative effectiveness research trials can threaten trial subjects' safety.

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Cell-free hemoglobin (CFH) levels are elevated in septic shock and are higher in nonsurvivors. Whether CFH is only a marker of sepsis severity or is involved in pathogenesis is unknown. This study aimed to investigate whether CFH worsens sepsis-associated injuries and to determine potential mechanisms of harm.

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Comparative effectiveness research can help guide the use of common, routine medical practices. However, to be safe and informative, such trials must include at least one treatment arm that accurately portrays current practices. While comparative effectiveness research is widely perceived as safe and to involve no or only minimal risks, these assumptions may not hold true if unrecognised deviations from usual care exist in one or more study arms.

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Tools for standardizing patient care can take many forms, including but not limited to, bundles, quality improvement and performance measures, guidelines, and protocols. Each is intended to improve compliance with interventions believed to be supported by the best available evidence, ensuring consistency of management across all patients with the ultimate goal of improving outcomes. However, in the ICU, patients typically present with complex acute illnesses and accompanying comorbidities, requiring careful tailoring of interventions and treatments for each individual patient.

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In 2015, the Centers for Medicare and Medicaid Services (CMS) instituted an all-or-none sepsis performance measure bundle (SEP-1) to promote high-quality, cost-effective care. Systematic reviews demonstrated only low-quality evidence supporting most of SEP-1's interventions. CMS has removed some but not all of these unproven components.

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The finding of toxicity in a meta-analysis of observational clinical studies of transfused longer stored red blood cells (RBC) and ethical issues surrounding aging blood for human studies prompted us to develop an experimental model of RBC transfusion. Transfusing older RBCs during canine pneumonia increased mortality rates. Toxicity was associated with in vivo hemolysis with release of cell-free hemoglobin (CFH) and iron.

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Background: In experimental canine septic shock, depressed circulating granulocyte counts were associated with a poor outcome and increasing counts with prophylactic granulocyte colony-stimulating factor (G-CSF) improved outcome. Therapeutic G-CSF, in contrast, did not improve circulating counts or outcome, and therefore investigation was undertaken to determine whether transfusing granulocytes therapeutically would improve outcome.

Study Design And Methods: Twenty-eight purpose-bred beagles underwent an intrabronchial Staphylococcus aureus challenge and 4 hours later were randomly assigned to granulocyte (40-100 × 10 cells) or plasma transfusion.

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Comparative effectiveness studies, referred to here as "usual-care" trials, seek to compare current medical practices for the same medical condition. Such studies are presumed to be safe and involve only minimal risks. However, that presumption may be flawed if the trial design contains "unusual" care, resulting in potential risks to subjects and inaccurately informed consent.

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Background: During sepsis, higher plasma cell-free hemoglobin (CFH) levels portend worse outcomes. In sepsis models, plasma proteins that bind CFH improve survival. In our canine antibiotic-treated Staphylococcus aureus pneumonia model, with and without red blood cell (RBC) exchange transfusion, commercial human haptoglobin (Hp) concentrates bound and compartmentalized CFH intravascularly, increased CFH clearance, and lowered iron levels, improving shock, lung injury, and survival.

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Objective: To address three controversial components in the Centers for Medicare and Medicaid Service's sepsis bundle for performance measure (SEP-1): antibiotics within 3 hours, a 30 mL/kg fluid infusion for all hypotensive patients, and repeat lactate measurements within 6 hours if initially elevated. We hypothesized that antibiotic- and fluid-focused bundles like SEP-1 would probably show benefit, but evidence supporting specific antibiotic timing, fluid dosing, or serial lactate requirements would not be concordant. Therefore, we performed a meta-analysis of studies of sepsis bundles like SEP-1.

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Dysfunction in the nitric oxide (NO) signaling pathway can lead to the development of pulmonary hypertension (PH) in mammals. Discovery of an alternative pathway to NO generation involving reduction from nitrate to nitrite and to NO has motivated the evaluation of nitrite as an alternative to inhaled NO for PH. In contrast, inhaled nitrate has not been evaluated to date, and potential benefits include a prolonged half-life and decreased risk of methemoglobinemia.

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Background: Storage temperature is a critical factor for maintaining red-blood cell (RBC) viability, especially during prolonged cold storage. The target range of 1 to 6°C was established decades ago and may no longer be optimal for current blood-banking practices.

Study Design And Methods: Human and canine RBCs were collected under standard conditions and stored in precision-controlled refrigerators at 2°C, 4°C, or 6°C.

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During the last half-century, numerous antiinflammatory agents were tested in dozens of clinical trials and have proven ineffective for treating septic shock. The observation in multiple studies that cell-free hemoglobin (CFH) levels are elevated during clinical sepsis and that the degree of increase correlates with higher mortality suggests an alternative approach. Human haptoglobin binds CFH with high affinity and, therefore, can potentially reduce iron availability and oxidative activity.

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Aim: To evaluate the risks of restrictive red blood cell transfusion strategies (haemoglobin 7-8 g dL ) in patients with and without known cardiovascular disease (CVD).

Background: Recent guidelines recommend restrictive strategies for CVD patients hospitalised for non-CVD indications, patients without known CVD and patients hospitalised for CVD corrective procedures.

Methods/materials: Database searches were conducted through December 2017 for randomised clinical trials that enrolled patients with and without known CVD, hospitalised either for CVD-corrective procedures or non-cardiac indications, comparing effects of liberal with restrictive strategies on major adverse coronary events (MACE) and death.

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Healthcare agencies should ensure that performance measures for accreditation or reimbursement are supported by sound scientific evidence and safeguarded from potential commercial influences, argue

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Unlabelled: This article has been corrected. To see what has changed, please read the Letter to the Editor and the authors' response. The original version (PDF) is appended to this article as a Supplement.

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The US Food and Drug Administration (FDA) held a workshop on red blood cell (RBC) product regulatory science on October 6 and 7, 2016, at the Natcher Conference Center on the National Institutes of Health (NIH) Campus in Bethesda, Maryland. The workshop was supported by the National Heart, Lung, and Blood Institute, NIH; the Department of Defense; the Office of the Assistant Secretary for Health, Department of Health and Human Services; and the Center for Biologics Evaluation and Research, FDA. The workshop reviewed the status and scientific basis of the current regulatory framework and the available scientific tools to expand it to evaluate innovative and future RBC transfusion products.

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