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SUMMARY: Aim: To evaluate the risks of restrictive red blood cell transfusion strategies (haemoglobin 7–8 g dL−1) 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. Results: In CVD patients not undergoing cardiac interventions, a liberal strategy decreased (P = 0·01) the relative risk (95% CI) (RR) of MACE [0·50 (0·29–0·86)] (I2 = 0%). Among patients without known CVD, the incidence of MACE was lower (1·7 vs 3·9%), and the effect of a liberal strategy on MACE [0·79, (0·39–1·58)] was smaller and non‐significant but not different from CVD patients (P = 0·30). Combining all CVD and non‐CVD patients, a liberal strategy decreased MACE [0·59, (0·39–0·91); P = 0·02]. Conversely, among studies reporting mortality, a liberal strategy decreased mortality in CVD patients (11·7% vs·13·3%) but increased mortality (19·2% vs 18·0%) in patients without known CVD [interaction P = 0·05; ratio of RR 0·73, (0·53–1·00)]. A liberal strategy also did not benefit patients undergoing cardiac surgery; data were insufficient for percutaneous cardiac procedures. Conclusions: In patients hospitalised for non‐cardiac indications, liberal transfusion strategies are associated with a decreased risk of MACE in both those with and without known CVD. However, this only provides a survival benefit to CVD patients not admitted for CVD‐corrective procedures. [ABSTRACT FROM AUTHOR]

Background and Objectives Preclinical studies generated the hypothesis that older stored red blood cells ( RBCs) can increase transfusion risks. To examine the most updated and complete clinical evidence and compare results between two trial designs, we assessed both observational studies and randomized controlled trials ( RCTs) studying the effect of RBC storage age on mortality. Materials and Methods Five databases were searched through December 2014 for studies comparing mortality using transfused RBCs having longer and shorter storage times. Results Analysis of six RCTs found no significant differences in survival comparing current practice (average storage age of 2 to 3 weeks) to transfusion of 1- to 10-day-old RBCs ( OR 0·91, 95% CI 0·77-1·07). RBC storage age was lower in RCTs vs. observational studies ( P = 0·01). The 31 observational studies found an increased risk of death ( OR 1·13, 95% CI 1·03-1·24) ( P = 0·01) with increasing age of RBCs, a different mortality effect than RCTs ( P = 0·02). Conclusion RCTs established that transfusion of 1- to 10-day-old stored RBCs is not superior to current practice. The apparent discrepancy in mortality between analyses of RCTs and observational studies may in part relate to differences in hypotheses tested and ages of stored RBCs studied. Further trials investigating 1- to 10-day-old stored RBC benefits would seem of lower priority than studies to determine whether 4- to 6-week stored units have safety and efficacy equivalent to the 2- to 3-week-old stored RBCs commonly transfused today. [ABSTRACT FROM AUTHOR]

The red blood cell ( RBC) storage interval has been extended from less than a week to the current storage interval of 6-8 weeks. Regulatory criteria for extending storage rely upon a minimal degree of hemolysis and acceptable in vivo 24-h post transfusion recovery. Clinical studies of safety and efficacy have never been required. Concerns have arisen that RBC toward the end of storage develop a 'storage lesion' with previously unrecognized toxicity. Of the several mechanisms proposed, the bolus of iron delivered to macrophages as a result of hemolysis of stored RBC might pose a particular risk to patients with existing infections. We developed a canine model of pneumonia to compare the toxicity of stored RBC transfusion. We described increased mortality after transfusion of old RBC. We found that transfused older RBC increased mortality, in vivo hemolysis, circulating cell-free hemoglobin that scavenges nitric oxide, and elevations of non-transferrin bound and plasma labile iron. Disappearance of circulating iron correlated with increased mortality, worsening pulmonary function, and bacterial proliferation. Washing decreased the mortality associated with transfusing older RBC, but had the opposite effect on fresher blood. With low doses of bacteria, survival was unaffected by the age of blood, whereas high bacteria doses masked any effect of RBC age on mortality. Older RBC may have adverse effects, but the patient's clinical status, the age, volume and method of preparation of the RBC may be critical variables. Several mechanisms may account for this toxicity, but in the presence of bacterial infection, availability of iron likely plays a major role. [ABSTRACT FROM AUTHOR]

Practice misalignments can occur in any clinical trial investigating a pre-existing therapy that is typically adjusted based on clinical characteristics outside of the trial setting. To eliminate the heterogeneity in clinical practice, recent trials investigating titrated therapies have randomized patients to fixed-dose regimens without including a routine care control group receiving titrated therapy. In these trials, the normal relationships between clinically important characteristics and therapy titration are disrupted. Within each arm of the trial, randomization creates subgroups of patients receiving levels of therapy inconsistent with current practices outside of the trial. These practice misalignments may have outcomes worse than routine care and may compromise patient safety. In addition, comparisons of trial arms with practice misalignments have limited interpretability and generalizability. In this review, we use examples from the literature to discuss how practice misalignments can impact the safety, results and conclusions of clinical trials. In addition, we discuss methods to characterize relationships between therapy titration and clinical characteristics and trial design strategies that may minimize practice misalignments. [ABSTRACT FROM AUTHOR]

Context: Hemoglobin-based blood substitutes (HBBSs) are infusible oxygen-carrying liquids that have long shelf lives, have no need for refrigeration or cross-matching, and are ideal for treating hemorrhagic shock in remote settings. Some trials of HBBSs during the last decade have reported increased risks without clinical benefit.Objective: To assess the safety of HBBSs in surgical, stroke, and trauma patients.Data Sources: PubMed, EMBASE, and Cochrane Library searches for articles using hemoglobin and blood substitutes from 1980 through March 25, 2008; reviews of Food and Drug Administration (FDA) advisory committee meeting materials; and Internet searches for company press releases.Study Selection: Randomized controlled trials including patients aged 19 years and older receiving HBBSs therapeutically. The database searches yielded 70 trials of which 13 met these criteria; in addition, data from 2 other trials were reported in 2 press releases, and additional data were included in 1 relevant FDA review.Data Extraction: Data on death and myocardial infarction (MI) as outcome variables.Results: Sixteen trials involving 5 different products and 3711 patients in varied patient populations were identified. A test for heterogeneity of the results of these trials was not significant for either mortality or MI (for both, I2 = 0%, P > or = .60), and data were combined using a fixed-effects model. Overall, there was a statistically significant increase in the risk of death (164 deaths in the HBBS-treated groups and 123 deaths in the control groups; relative risk [RR], 1.30; 95% confidence interval [CI], 1.05-1.61) and risk of MI (59 MIs in the HBBS-treated groups and 16 MIs in the control groups; RR, 2.71; 95% CI, 1.67-4.40) with these HBBSs. Subgroup analysis of these trials indicated the increased risk was not restricted to a particular HBBS or clinical indication.Conclusion: Based on the available data, use of HBBSs is associated with a significantly increased risk of death and MI. [ABSTRACT FROM AUTHOR]

Background: Risk of death may influence the efficacy of anti-inflammatory agents in sepsis. "Physiologic" dose corticosteroids, while improving survival in earlier trials with higher control mortality rates (>50%), were not beneficial in the recent CORTICUS trial with lower control mortality (31%). We investigated whether risk of death altered the effects of hydrocortisone in a mouse pneumonia model.Methods: Mice (n=637) challenged with high, medium or low intratracheal E. coli doses were randomized to receive one of three hydrocortisone doses (5, 25 or 125 mg/kg) or normal saline (NS) only (control) for 4 days. All animals were treated with similar volumes of ceftriaxone and NS support following E. coli and were observed for 168 h.Results: Decreasing E. coli doses reduced control mortality rates (from 94 to 12%). In similar patterns (not significant) each hydrocortisone dose increased the odds ratio (OR) of survival (95% confidence interval) with each E. coli dose (ORs ranging from 1.2 [0.4, 3.7] to 6.1 [0.6, 61.0]). The effect of hydrocortisone on the OR was not related to control mortality rate (r=-0.13, p=0.29) and overall was highly significant (2.04 [1.37, 3.03], p=0.0004). In randomly selected animals 48 h after the highest E. coli dose, compared with the control, hydrocortisone (125 mg/kg) significantly decreased IL-6, INFgamma, and nitric oxide levels.Conclusions: In this mouse model the beneficial effects of hydrocortisone were independent of risk of death. These findings suggest that factors other than risk of death may underlie the differing effects of corticosteroids in recent sepsis trials. [ABSTRACT FROM AUTHOR]

Excessive production of inflammatory mediators during invasive infection plays a key role in the pathogenesis of septic shock. In an attempt to improve survival of patients with this lethal syndrome, agents were developed to selectively inhibit mediators in this inflammatory response. Despite promising preclinical results, several different mediator-specific anti-inflammatory agents failed to demonstrate significant benefit in patients. There was, however, a significant difference in mortality between preclinical and clinical trials. The median control mortality in preclinical trials, performed almost uniformly in highly lethal sepsis models, was 88%. In clinical trials however, the median control mortality rate was much lower, at 41%. A recent meta-regression analysis of these preclinical and clinical trials in combination with prospective confirmatory studies demonstrated that risk of death as assessed by control group mortality rate significantly altered the treatment effect of these agents in both humans and animals. While anti-inflammatory agents were very beneficial in groups with high control mortality rates, they were ineffective or harmful in groups with low control mortality rates. Thus, variation in the risk of death due to sepsis provides a basis for the marked difference in the efficacy of these anti-inflammatory agents in preclinical and clinical trials over the last decade. In contrast to mediator-specific anti-inflammatory agents, glucocorticoids and activated protein C have recently demonstrated significant beneficial effects in individual clinical trials. However, glucocorticoids were studied only in patients with vasopressor-dependent septic shock, which is associated with a high control mortality rate (i.e. 61%) similar to the level at which mediator-specific agents would have been expected to be markedly beneficial. Furthermore, consistent with earlier findings for mediator-specific anti-inflammatory agents, analysis of the activated protein C study also demonstrated a relationship between risk of death and effect of treatment. Developing better methods to define high-risk septic populations for treatment with anti-inflammatory agents will increase the efficacy of this therapeutic approach and minimize its potential for harm. [ABSTRACT FROM AUTHOR]

100 years after the discovery of a bacterial 'endotoxin', 50 years after the introduction of antibiotics and 25 years after the routine use of intensive care units to support septic shock patients, Gram-negative infections continue to account for significant morbidity and mortality. In the coming decade, basic research on the structure/function of LPS, the cytokine cascade, and receptor-mediated intracellular signalling responses to LPS and cytokines will provide a greater understanding of the molecular, cellular and systemic responses to endotoxin and infection. New therapeutic agents now emerging from research, and better designed clinical trials to assess those agents will contribute to the next significant decline in sepsis- and shock-related morbidity and mortality. This article summarizes the findings of a workshop convened at the National Institutes of Health (NIH) to examine current research on endotoxin and Gram-negative septic shock. [ABSTRACT FROM PUBLISHER]

Purpose: To review selected new therapies for septic shock designed to inhibit bacterial toxins or endogenous mediators of inflammation.Data Sources: Scientific journals, scientific meeting proceedings, and Food and Drug Administration advisory committee proceedings.Study Selection and Extraction: Preclinical and clinical data from trials using core-directed antiendotoxin antibodies and anticytokine therapies for sepsis and studies in animal models of sepsis from our laboratory.Results Of Data Synthesis: Ten clinical trials using core-directed antiendotoxin antibodies produced inconsistent results and did not conclusively establish the safety or benefit of this approach. Both anti-interleukin-1 and anti-tumor necrosis factor (TNF) therapies have been beneficial in some animal models of sepsis but did not clearly improve survival in initial human trials, and one anti-TNF therapy actually produced harm. Neutrophils, another target for therapeutic intervention, protect the host from infection but may also contribute to the development of tissue injury during sepsis. In a canine model of septic shock, granulocyte colony-stimulating factor increased the number of circulating neutrophils and improved survival, but an anti-integrin (CD11/18) antibody that inhibits neutrophil function worsened outcome. Nitric oxide, a vasodilator produced by the host, causes hypotension during septic shock but may also protect the endothelium and maintain organ blood flow. In dogs challenged with endotoxin, the inhibition of nitric oxide production decreased cardiac index and did not improve survival.Conclusions: No new therapy for sepsis has shown clinical efficacy. Perhaps more accurate clinical and laboratory predictors are needed to identify patients who may benefit from a given treatment strategy. On the other hand, the therapeutic premises may be flawed. Targeting a single microbial toxin such as endotoxin may not represent a viable strategy for treating a complex inflammatory response to diverse gram-negative bacteria. Similarly, the strategy of inhibiting the host inflammatory response may not be beneficial because immune cells and cytokines play both pathogenic and protective roles. Finally, our scientific knowledge of the complex timing of mediator release and balance during sepsis may be insufficient to develop successful therapeutic interventions for this syndrome. [ABSTRACT FROM AUTHOR]

Septic shock is the commonest cause of death in intensive care units. Although sepsis usually produces a low systemic vascular resistance and elevated cardiac output, strong evidence (decreased ejection fraction and reduced response to fluid administration) suggests that the ventricular myocardium is depressed and the ventricle dilated. In survivors, these abnormalities are reversible. Failure to develop ventricular dilatation in nonsurvivors suggests that dilatation is a compensatory mechanism needed to maintain adequate cardiac output. With a canine model of septic shock that is very similar to human sepsis, myocardial depression was confirmed using load-independent measures of ventricular performance. Endotoxin administration to humans simulates the qualitative, cardiovascular abnormalities of sepsis. The pathogenesis of septic shock is extraordinarily complex. Diverse microorganisms can generate toxins, stimulating release of potent mediators that act on vasculature and myocardium. A circulating myocardial depressant substance has been closely associated with the myocardial depression of human septic shock. Therapy has emphasized early use of antibiotics, critical care monitoring, aggressive volume resuscitation, and, if shock continues, use of inotropic agents and vasopressors. Pharmacologic or immunologic antagonism of endotoxin or other mediators may prove to enhance survival in this highly lethal syndrome. [ABSTRACT FROM AUTHOR]

Presents a case report of a patient with cardiopulmonary toxicity after liposomal amphotericin B infusion. Facts of the case; Methodology; Discussion.