Aldosterone and Vascular Mineralocorticoid Receptors in Murine Endotoxic and Human Septic Shock*:

The Mineralocorticoid Receptor in the Vasculature: Friend or Foe?

Originally described as the renal aldosterone receptor that regulates sodium homeostasis, it is now clear that mineralocorticoid receptors (MRs) are widely expressed, including in vascular endothelial and smooth muscle cells. Ample data demonstrate that endothelial and smooth muscle cell MRs contribute to cardiovascular disease in response to risk factors (aging, obesity, hypertension, atherosclerosis) by inducing vasoconstriction, vascular remodeling, inflammation, and oxidative stress. Extrapolating from its role in disease, evidence supports beneficial roles of vascular MRs in the context of hypotension by promoting inflammation, wound healing, and vasoconstriction to enhance survival from bleeding or sepsis. Advances in understanding how vascular MRs become activated are also reviewed, describing transcriptional, ligand-dependent, and ligand-independent mechanisms. By synthesizing evidence describing how vascular MRs convert cardiovascular risk factors into disease (the vascular MR as a foe), we postulate that the teleological role of the MR is to coordinate responses to hypotension (the MR as a friend).

The Evolving Understanding of Glucocorticoid Treatment in Septic Shock

There has long been interest in adjunctive therapies in septic shock because this condition continues to carry a significant risk of death and long-term sequelae.1 Adjunctive therapy with glucocorticoids has been the target of many controlled trials in septic shock on the basis of glucocorticoids' multiple putative benefits, including modulation of an excess inflammatory response to infection and treatment of relative adrenal insufficiency due to imbalance in the hypothalamic-pituitary-adrenal axis. Despite this effort, decades of conflicting trial results have left clinicians without consistent guidance about when, and for whom, to implement glucocorticoid therapy.

Mineralocorticoid pathway in retinal health and diseases

In the retina, the mineralocorticoid receptor (MR) is expressed in retinal and choroidal vessels and in cells from neural and glial origins. Like in the brain, the major ligand of the MR is cortisol and the MR/glucocorticoid receptor (GR) balance regulates the activation of the MR pathway. Experimental MR pathway activation using either pharmacological agents or transgenic manipulation favors retinal and choroidal pathology. In various models of retinal diseases, such as glaucomatous neuropathy, retinopathy of prematurity, ischemic retinopathies, diabetic retinopathy and choroidal neovascularization, MR antagonism exerts beneficial effects, demonstrating its potential in the treatment of major blinding retinal diseases. But specific formulations are required to optimize the bioavailability of MR antagonists in various compartments of the eye and molecular biomarkers of MR pathway activation remain to be identify in humans to select patients amenable to clinical trials.

Myeloid Mineralocorticoid Receptor Transcriptionally Regulates P-Selectin Glycoprotein Ligand-1 and Promotes Monocyte Trafficking and Atherosclerosis

Objective

MR (mineralocorticoid receptor) activation associates with increased risk of cardiovascular ischemia while MR inhibition reduces cardiovascular-related mortality and plaque inflammation in mouse atherosclerosis. MR in myeloid cells (My-MR) promotes inflammatory cell infiltration into injured tissues and atherosclerotic plaque inflammation by unclear mechanisms. Here, we examined the role of My-MR in leukocyte trafficking and the impact of sex.

Approach and Results

We confirm in vivo that My-MR deletion (My-MR-KO) in ApoE-KO mice decreased plaque size. Flow cytometry revealed fewer plaque macrophages with My-MR-KO. By intravital microscopy, My-MR-KO significantly attenuated monocyte slow-rolling and adhesion to mesenteric vessels and decreased peritoneal infiltration of myeloid cells in response to inflammatory stimuli in male but not female mice. My-MR-KO mice had significantly less PSGL1 (P-selectin glycoprotein ligand 1) mRNA in peritoneal macrophages and surface PSGL1 protein on circulating monocytes in males. In vitro, MR activation with aldosterone significantly increased PSGL1 mRNA only in monocytes from MR-intact males. Similarly, aldosterone induced, and MR antagonist spironolactone inhibited, PSGL1 expression in human U937 monocytes. Mechanistically, aldosterone stimulated MR binding to a predicted MR response element in intron-1 of the PSGL1 gene by ChIP-qPCR. Reporter assays demonstrated that this PSGL1 MR response element is necessary and sufficient for aldosterone-activated, MR-dependent transcriptional activity.

Conclusions

These data identify PSGL1 as a My-MR target gene that drives leukocyte trafficking to enhance atherosclerotic plaque inflammation. These novel and sexually dimorphic findings provide insight into increased ischemia risk with MR activation, cardiovascular protection in women, and the role of MR in atherosclerosis and tissue inflammation.

Examination of the association of steroids with fluid accumulation in critically ill patients, considering the possibility of biases

Glucocorticoids might have significant influence on positive fluid balance, mostly due to their mineralocorticoid effect. We assessed the association between glucocorticoid therapy and fluid balance in septic patients, in the intensive care unit (ICU). We considered two definitions of exposure: daily exposure to glucocorticoids and glucocorticoid treatment at any time. Of 945 patients, 375 were treated with glucocorticoids in the ICU. We applied four regression models. In the first, fluid balance did not differ during days with and without glucocorticoid treatment, among patients treated and not treated with glucocorticoids in the ICU. In our second model, daily fluid balance was increased in patients who were ever treated with glucocorticoids during their ICU stay compared to untreated patients. In the third model, which included only patients treated with glucocorticoids during their ICU stay, glucocorticoid treatment days were not associated with daily fluid balance. In the last model, on "steroid-free days", patients who received glucocorticoid treatment during their ICU stay had a positive fluid balance compared to those who were never treated with steroids. Despite their known mineralocorticoid activity, glucocorticoids themselves appear not to contribute substantially to fluid retention. This work highlights the importance of precise selection of variables to mitigate biases.

G Protein-Coupled Estrogen Receptor 1 (GPER1) Mediates Aldosterone-Induced Endothelial Inflammation in a Mineralocorticoid Receptor-Independent Manner

OBJECTIVE

It has been increasingly appreciated that G protein-coupled estrogen receptor 1 (GPER1) mediates both proinflammatory and anti-inflammatory response of estrogen. It is also involved in some rapid vascular effects of aldosterone in a mineralocorticoid receptor (MR) independent manner. However, whether GPER1 mediates aldosterone-induced inflammation response in endothelial cells and its relationship with MR are yet undetermined and therefore require further explanation.

METHOD

Based on the hypothesis that GPER1 plays a role in the aldosterone-related vascular inflammation, the present study utilized a model of human umbilical vein endothelial cells transfected with MR siRNA and induced for inflammatory response with increasing concentration of aldosterone.

RESULTS

It was discovered that induction of aldosterone had no effect on the expression of GPER1 but promoted the expression of MR. Suppression of MR did not influence GPER1 expression, and GPER1 was capable of mediating part of aldosterone-induced endothelial inflammatory response. This effect may involve phosphoinositide 3-kinases (PI3K) pathway signaling.

CONCLUSION

These findings not only demonstrated the role of GPER1 in aldosterone-induced vascular inflammation but also suggested an alternative for pharmaceutical treatment of hyperaldosteronism considering the unsatisfying effect on cardiovascular risks with MR antagonists.

Hydrocortisone with fludrocortisone for septic shock: a systematic review and meta-analysis

Aim

Combined hydrocortisone and fludrocortisone therapy for septic shock has not been evaluated with an independent systematic review. We aimed to elucidate the beneficial effects of a dual corticosteroid treatment regime involving both hydrocortisone and fludrocortisone for adult patients with septic shock on mortality.

Methods

We searched the Medline, Cochrane CENTRAL, and ICHUSHI databases for reports published before April 2019. We included randomized controlled trials that compared the use of both hydrocortisone and fludrocortisone with either corticosteroid‐free or hydrocortisone‐only treatments on adult patients with septic shock. Three researchers independently reviewed the studies. The meta‐analyses were undertaken to assess primary outcome (28‐day mortality) and secondary outcomes (in‐hospital mortality, long‐term mortality, shock reversal, and adverse events).

Results

Among the four studies eligible for data synthesis, we included 2,050 patients from three studies for quantitative synthesis. All studies used similar regimens (hydrocortisone and fludrocortisone for 7 days without tapering). The 28‐day mortality rate was reduced after dual corticosteroid treatment (risk ratio, 0.88; 95% confidence intervals [CI], 0.78–0.99). The heterogeneity between the studies was low (I² = 0%). Patients who underwent dual corticosteroid treatment had lower long‐term mortality rates (risk ratio, 0.90; 95% CI, 0.83–0.98) and higher rate of shock reversal after 28 days (odds ratio, 1.06; 95% CI, 1.01–1.12) than control patients. Adverse events (except for hyperglycemia) were similar among the treatment groups.

Conclusions

The available evidence suggests that a combination of fludrocortisone and hydrocortisone is more effective than adjunctive therapy and could be recommended for septic shock.

Corticosteroids for Septic Shock: Another Chapter in the Saga

The use of corticosteroids in the management of septic shock has been a highly debated topic for quite some time. Corticosteroids have the ability to combat hyperinflammatory and exaggerated vasodilatory responses, as well as to sensitize adrenergic receptors to decrease the duration of shock. While helpful clinically, this has not translated to consistent mortality benefits. Conflicting results from 2 landmark trials published in 2002 and 2008 have led to varying clinical practices, and a clearly defined role of corticosteroids in septic shock is lacking. A decade later, an influx of new data derived from 2 more large trials continues to echo diverging viewpoints regarding patient mortality. In combination with fluctuating study designs (eg, adjunctive therapies and shock management) and patient populations (eg, illness severity), generalized conclusions are still difficult to draw. Despite these challenges, this review critically analyzes recently published data in the context of historical debate to provide an updated comment on the role of corticosteroids in septic shock. In summary, hydrocortisone therapy is likely to demonstrate maximal benefit when initiated on patients with septic shock and organ failure refractory to vasopressor therapy and should be used judiciously in other settings as it comes without a demonstrated benefit in mortality and increased potential for adverse effects.

General Adaptation in Critical Illness: Glucocorticoid Receptor-alpha Master Regulator of Homeostatic Corrections

In critical illness, homeostatic corrections representing the culmination of hundreds of millions of years of evolution, are modulated by the activated glucocorticoid receptor alpha (GRα) and are associated with an enormous bioenergetic and metabolic cost. Appreciation of how homeostatic corrections work and how they evolved provides a conceptual framework to understand the complex pathobiology of critical illness. Emerging literature place the activated GRα at the center of all phases of disease development and resolution, including activation and re-enforcement of innate immunity, downregulation of pro-inflammatory transcription factors, and restoration of anatomy and function. By the time critically ill patients necessitate vital organ support for survival, they have reached near exhaustion or exhaustion of neuroendocrine homeostatic compensation, cell bio-energetic and adaptation functions, and reserves of vital micronutrients. We review how critical illness-related corticosteroid insufficiency, mitochondrial dysfunction/damage, and hypovitaminosis collectively interact to accelerate an anti-homeostatic active process of natural selection. Importantly, the allostatic overload imposed by these homeostatic corrections impacts negatively on both acute and long-term morbidity and mortality. Since the bioenergetic and metabolic reserves to support homeostatic corrections are time-limited, early interventions should be directed at increasing GRα and mitochondria number and function. Present understanding of the activated GC-GRα's role in immunomodulation and disease resolution should be taken into account when re-evaluating how to administer glucocorticoid treatment and co-interventions to improve cellular responsiveness. The activated GRα interdependence with functional mitochondria and three vitamin reserves (B1, C, and D) provides a rationale for co-interventions that include prolonged glucocorticoid treatment in association with rapid correction of hypovitaminosis.

Combination of low-dose glucocorticosteroids and mineralocorticoids as adjunct therapy for adult patients with septic shock: A systematic review and meta-analysis of randomized trials and observational studies

Background:

The role of the combination of glucocorticosteroids and mineralocorticosteroids in treating septic shock is not well-defined. The aim of this study was to perform a systematic review and meta-analysis of the randomized controlled trials and observational studies assessing the effect of low-dose hydrocortisone and fludrocortisone on patients with septic shock.

Materials and Methods:

MEDLINE, Scopus, and Cochrane databases were reviewed. A random effect model meta-analysis was used and I-square was used to assess the heterogeneity. Short-term mortality was chosen as our primary end point. A subgroup analysis was performed including only the randomized controlled trials.

Results:

A total of 10,550 patients were included in this meta-analysis. Administration of the steroid combination was associated with improved short-term mortality (odds ratio, 0.78, confidence interval, 0.64–0.96), intensive care unit mortality, and shock reversal, without increase in steroid-related side effects, such as secondary infection or gastrointestinal hemorrhage.

Conclusion:

This systematic review and meta-analysis showed that use of the combination of glucocorticosteroids and mineralocorticosteroids has a beneficial impact on short-term mortality, intensive care unit mortality, and shock reversal, without increasing the incidence of gastrointestinal hemorrhage or superinfection in patients with septic shock, when used as an adjunct treatment to the established standard of care.

Vascular mineralocorticoid receptor activation and disease

Mineralocorticoid receptor activation in endothelial and smooth muscle cells can promote vascular disease by increasing oxidative stress, promoting inflammation, accelerating vascular stiffness, remodeling, and calcification, altering vessel responsiveness to various vasoactive factors, thus altering vascular tone and blood pressure, and by altering angiogenesis. Here, we review the recent evidence highlighting the impact of vascular mineralocorticoid receptor activation in pathological situations, including kidney injury, vascular injury associated with metabolic diseases, atherosclerosis, cerebral vascular injury during hypertension, vascular stiffening and aging, pulmonary hypertension, vascular calcification, cardiac remodeling, wound healing, inflammation, thrombosis, and disorders related to angiogenic defects in the eye. The possible mechanisms implicating mineralocorticoid receptor activation in various vascular disorders are discussed. Altogether, recent evidence points towards pharmacological mineralocorticoid receptor inhibition as a strategy to treat diseases in which overactivation of the mineralocorticoid receptor in endothelial and/or smooth muscle cells may play a pivotal role.

Adjunctive Corticosteroid Treatment in Septic Shock

Two recent randomized controlled trials have provided new data to inform opinion on the use of corticosteroids in septic shock. This article discusses the background and rationale for corticosteroid use, compares the findings and methodologies of the new trials, and provides suggestions for practice.

Hydrocortisone in Vasodilatory Shock

Vasodilatory shock is the most common type of circulatory shock in critically ill patients; sepsis the predominant cause. Steroid use in septic shock gained favor in the 1970s; however, studies of high-dose steroids demonstrated excess morbidity and mortality. Lower dosage steroid use was driven by trials demonstrating improved hemodynamic status and the possibility of relative adrenal insufficiency; however, divergent results led to uncertainty about hydrocortisone treatment. Two recent trials are likely to reinforce the role of steroids in septic shock and change the recommendation in future clinical practice guidelines. Future work could include elucidating mechanisms of shock reversal, interaction of hydrocortisone with other agents, identifying steroid responsiveness using biochemical or gene signatures, and clarifying the role of fludrocortisone.

Catecholamine Vasopressor Support Sparing Strategies in Vasodilatory Shock

Shock syndromes are associated with unacceptably high rates of mortality in critically ill patients despite advances in therapeutic options. Vasodilatory shock is the most common type encountered in the intensive care unit. It is manifested by cardiovascular failure, peripheral vasodilatation, and arterial hypotension leading to tissue hypoperfusion and organ failure. Hemodynamic support is typically initiated with fluid resuscitation strategies and administration of adrenergic vasopressor agents in nonresponsive patients to restore arterial pressure with subsequent adequate organ reperfusion. Unfortunately, high catecholamine dosing requirements may be necessary to achieve targeted hemodynamic goals that may increase the risk of vasopressor-induced adverse events. The purpose of this article is to review the clinical efficacy and safety data and potential role in therapy for catecholamine-sparing agents in vasodilatory shock. Adjunctive therapeutic options to reduce vasoactive support requirements without compromising arterial pressure include arginine vasopressin and analogs, corticosteroids, midodrine, methylene blue, and angiotensin II. Although concomitant vasopressin and corticosteroids have a more defined role in evidence-based guidelines for managing shock, clinicians may consider other potential catecholamine-sparing agents.

Recent Updates in the Pharmacological Management of Sepsis and Septic Shock: A Systematic Review Focused on Fluid Resuscitation, Vasopressors, and Corticosteroids

OBJECTIVE

Describe recent developments in the pharmacological management of sepsis and septic shock, focusing on fluid resuscitation, vasopressors, and corticosteroids.

DATA SOURCES

A literature search limited to randomized controlled trials written in the English language reporting mortality and other clinically relevant outcomes that were published from July 1, 2016, to August 31, 2018, in patients aged ≥ 18 years. Titles and abstracts were reviewed for relevance. References for pertinent review articles were also reviewed.

STUDY SELECTION AND DATA EXTRACTION

Relevant randomized controlled trials conducted in patients meeting the pre-defined inclusion criteria were considered for inclusion.

DATA SYNTHESIS

From an initial search that identified 147 studies, 14 original research studies met inclusion criteria and were included in this review. Risk of bias (ROB) was assessed using the Revised Cochrane ROB assessment tool, with most included studies having a low ROB. Relevance to Patient Care and Clinical Practice: Sepsis and septic shock pose a significant burden on public health. Despite advances in our understanding of sepsis, mortality remains unacceptably high. Recent developments in the pharmacological management of septic shock have focused on determining optimal composition and dosage of fluid resuscitation, enhanced use of vasopressor therapy, and clarifying the role of corticosteroids. This systematic review will provide recommendations for application to practice focusing on recent research on these topics.

CONCLUSIONS

Although recent developments in the pharmacological management of sepsis are encouraging, clinicians must be keen to utilize patient-specific factors to guide therapy and continue to strive to address the remaining unanswered questions.

Effect of Low-Dose Hydrocortisone Therapy in Adult Patients With Septic Shock: A Meta-Analysis With Trial Sequential Analysis of Randomized Controlled Trials

BACKGROUND

The efficacy of low-dose hydrocortisone therapy in the management of septic shock remains controversial in critical care for many years. Hence, we performed this meta-analysis of randomized controlled trials (RCTs) with trial sequential analysis (TSA) to evaluate its effect on clinical outcome among adult patients with septic shock.

METHODS

We identified relevant RCTs published from inception to March 7, 2018 comparing low-dose hydrocortisone with placebo or no intervention in adults admitted to the intensive care unit (ICU) for septic shock. Meta-analyses were performed for the primary and secondary outcomes. The risk of bias was assessed using the Cochrane Collaboration's instrument. Trial sequential analysis was used to pool the results from the included studies for the primary outcomes.

RESULTS

Thirteen studies were retrieved by our literature search strategy. There were no significant differences in 28-day mortality (odds ratio [OR] = 0.90, 95% confidence interval [CI] = 0.81-1.00; P = .05) and hospital mortality (OR = 0.91, 95% CI = 0.82-1.02; P = .09) between the 2 groups, which were confirmed by TSA. However, there was a significant improvement in shock reversal in the hydrocortisone group (OR = 1.33, 95% CI = 1.02-1.72; P = .03). Furthermore, subgroup analyses revealed that hydrocortisone plus fludrocortisone statistically reduced the rate of 28-day mortality (OR = 0.79, 95% CI = 0.64-0.97; P = .03), ICU mortality (OR = 0.77, 95% CI = 0.63-0.95; P = .02), and hospital mortality (OR = 0.77, 95% CI = 0.63-0.95; P = .01) in comparison with the placebo, the results were also confirmed by TSA.

CONCLUSION

Among adult patients with septic shock, the use of low-dose hydrocortisone compared with control did not confer overall survival benefits, albeit improving shock reversal rate. The benefit of reducing 28-day mortality, ICU mortality, and hospital mortality was observed in combination use of hydrocortisone and fludrocortisone.

Effect of adjunctive corticosteroids on clinical outcomes in adult patients with septic shock - a meta-analysis of randomized controlled trials and trial sequential analysis

PURPOSE

To assess the effect of corticosteroids on clinical outcomes in patients with septic shock.

MATERIALS AND METHODS

We searched databases for eligible randomized controlled trials (RCTs) published prior to March 12, 2018. The relative risk (RR), mean difference (MD) and 95% confidence intervals (CI) were determined. Trial sequential analysis (TSA) were performed.

RESULTS

Seventeen RCTs were identified. Overall, corticosteroid therapy was not associated with a lower short-term mortality compared with placebo. Sub-analysis of trials with a low risk of bias demonstrated a beneficial effect of corticosteroids in reducing short-term mortality. Sub-analysis revealed that a daily dose of 200 mg hydrocortisone provided no benefit in reducing short-term mortality (random-effects RR = 0.98, 95% CI: 0.90-1.06, P = 0.555; TSA-adjusted CI: 0.88-1.09; I² = 0%), and the boundary for futility was crossed. However, a significant reduction in short-term mortality was found in a subgroup of trials that received dual corticosteroids (random-effects RR = 0.88; 95% CI: 0.79-0.97, P = 0.013; I² = 0%), but this benefit disappeared after adjustment with TSA (TSA-adjusted CI: 0.76-1.02).

CONCLUSIONS

Future trials are unlikely to detect a reduction in short-term mortality at a daily doses of 200 mg hydrocortisone. More evidence is required to confirm the beneficial effects of dual corticosteroid therapy.

Immune Effects of Corticosteroids in Sepsis

Sepsis, a life-threatening organ dysfunction, results from a dysregulated host response to invading pathogens that may be characterized by overwhelming systemic inflammation or some sort of immune paralysis. Sepsis remains a major cause of morbidity and mortality. Treatment is nonspecific and relies on source control and organ support. Septic shock, the most severe form of sepsis is associated with the highest rate of mortality. Two large multicentre trials, undertaken 15 years apart, found that the combination of hydrocortisone and fludrocortisone significantly reduces mortality in septic shock. The corticosteroids family is composed of several molecules that are usually characterized according to their glucocorticoid and mineralocorticoid power, relative to hydrocortisone. While the immune effects of glucocorticoids whether mediated or not by the intracellular glucocorticoid receptor have been investigated for several decades, it is only very recently that potential immune effects of mineralocorticoids via non-renal mineralocorticoid receptors have gained popularity. We reviewed the respective role of glucocorticoids and mineralocorticoids in counteracting sepsis-associated dysregulated immune systems.

The Deletion of Endothelial Sodium Channel α (αENaC) Impairs Endothelium-Dependent Vasodilation and Endothelial Barrier Integrity in Endotoxemia in Vivo

The role of epithelial sodium channel (ENaC) activity in the regulation of endothelial function is not clear. Here, we analyze the role of ENaC in the regulation of endothelium-dependent vasodilation and endothelial permeability in vivo in mice with conditional αENaC subunit gene inactivation in the endothelium (endo-αENaC^KO mice) using unique MRI-based analysis of acetylcholine-, flow-mediated dilation and vascular permeability. Mice were challenged or not with lipopolysaccharide (LPS, from Salmonella typhosa, 10 mg/kg, i.p.). In addition, changes in vascular permeability in ex vivo organs were analyzed by Evans Blue assay, while changes in vascular permeability in perfused mesenteric artery were determined by a FITC-dextran-based assay. In basal conditions, Ach-induced response was completely lost, flow-induced vasodilation was inhibited approximately by half but endothelial permeability was not changed in endo-αENaC^KO vs. control mice. In LPS-treated mice, both Ach- and flow-induced vasodilation was more severely impaired in endo-αENaC^KO vs. control mice. There was also a dramatic increase in permeability in lungs, brain and isolated vessels as evidenced by in vivo and ex vivo analysis in endotoxemic endo-αENaC^KO vs. control mice. The impaired endothelial function in endotoxemia in endo-αENaC^KO was associated with a decrease of lectin and CD31 endothelial staining in the lung as compared with control mice. In conclusion, the activity of endothelial ENaC in vivo contributes to endothelial-dependent vasodilation in the physiological conditions and the preservation of endothelial barrier integrity in endotoxemia.

Hydrocortisone plus Fludrocortisone for Adults with Septic Shock

BACKGROUND

Septic shock is characterized by dysregulation of the host response to infection, with circulatory, cellular, and metabolic abnormalities. We hypothesized that therapy with hydrocortisone plus fludrocortisone or with drotrecogin alfa (activated), which can modulate the host response, would improve the clinical outcomes of patients with septic shock.

METHODS

In this multicenter, double-blind, randomized trial with a 2-by-2 factorial design, we evaluated the effect of hydrocortisone-plus-fludrocortisone therapy, drotrecogin alfa (activated), the combination of the three drugs, or their respective placebos. The primary outcome was 90-day all-cause mortality. Secondary outcomes included mortality at intensive care unit (ICU) discharge and hospital discharge and at day 28 and day 180 and the number of days alive and free of vasopressors, mechanical ventilation, or organ failure. After drotrecogin alfa (activated) was withdrawn from the market, the trial continued with a two-group parallel design. The analysis compared patients who received hydrocortisone plus fludrocortisone with those who did not (placebo group).

RESULTS

Among the 1241 patients included in the trial, the 90-day mortality was 43.0% (264 of 614 patients) in the hydrocortisone-plus-fludrocortisone group and 49.1% (308 of 627 patients) in the placebo group (P=0.03). The relative risk of death in the hydrocortisone-plus-fludrocortisone group was 0.88 (95% confidence interval, 0.78 to 0.99). Mortality was significantly lower in the hydrocortisone-plus-fludrocortisone group than in the placebo group at ICU discharge (35.4% vs. 41.0%, P=0.04), hospital discharge (39.0% vs. 45.3%, P=0.02), and day 180 (46.6% vs. 52.5%, P=0.04) but not at day 28 (33.7% and 38.9%, respectively; P=0.06). The number of vasopressor-free days to day 28 was significantly higher in the hydrocortisone-plus-fludrocortisone group than in the placebo group (17 vs. 15 days, P<0.001), as was the number of organ-failure-free days (14 vs. 12 days, P=0.003). The number of ventilator-free days was similar in the two groups (11 days in the hydrocortisone-plus-fludrocortisone group and 10 in the placebo group, P=0.07). The rate of serious adverse events did not differ significantly between the two groups, but hyperglycemia was more common in hydrocortisone-plus-fludrocortisone group.

CONCLUSIONS

In this trial involving patients with septic shock, 90-day all-cause mortality was lower among those who received hydrocortisone plus fludrocortisone than among those who received placebo. (Funded by Programme Hospitalier de Recherche Clinique 2007 of the French Ministry of Social Affairs and Health; APROCCHSS ClinicalTrials.gov number, NCT00625209 .).

Vasoplegia in patients with sepsis and septic shock: pathways and mechanisms

Sepsis is one of the most frequent causes of death among patients in intensive care units. Many therapeutic strategies have been assessed without the desired success rates. A key risk factor for death is hypotension due to vasodilatation with vascular hyposensitivity. However, the pathways underlying this process remain unclear. Endotoxemia induces inflammatory mediators, and this is followed by vasoplegia and decreased cardiac contractility. Although inhibition of these mediators diminishes mortality rates in animal models, this phenomenon has not been confirmed in humans. Downregulation of vasoconstrictive receptors such as angiotensin receptors, adrenergic and vasopressin receptors is seen in sepsis, which is associated with a hyporesponsiveness to vasoconstrictive mediators. Animal studies have verified that receptor downregulation is linked to the above-mentioned inflammatory mediators. Anti-inflammatory therapy with glucocorticoids reportedly improves responsiveness to catecholamines with higher survival in rats, although this has not been shown to be clinically significant in humans. Hence, there is an urgent need for in-depth studies investigating the underlying mechanisms of vasoplegia to allow for development of effective therapeutic strategies for the treatment of sepsis.