Endocrine and Metabolic Alterations in Sepsis and Implications for Treatment

Exploring the potential mechanism of Xuebijing injection against sepsis based on metabolomics and network pharmacology

Sepsis is a major contributor to the death of critically ill patients globally, in which metabolic disturbance is observed. Xuebijing injection (XBJ), a well-known traditional Chinese medicine, has received approval by the State Food and Drug Administration (SFDA) of China owing to its satisfactory clinical therapeutic effect. Nowadays, it has been applied clinically to the treatment of sepsis, but its effect on metabolic disorders remains unclear. In the present study, we sought to explore its underlying mechanism by employing a combination of network pharmacology and metabolomics. Initially, its protective effects were validated using a sepsis rat model created through cecal ligation puncture (CLP). Subsequently, the metabonomic strategy was utilized to discriminate the differential metabolic markers. Meanwhile, a comprehensive view of the potential ingredient-target-disease network was constructed based on a network pharmacology analysis. Next, the network diagram was constructed by integrating the results of network pharmacology and metabonomics. Finally, qRT-PCR together with Western blot was used to validate the expression levels of the associated genes. Based on our findings, we identified 34 differential metabolites in the sepsis group and 26 distinct metabolites in the XBJ group, with 8 common biological metabolites predominantly associated with arginine and proline metabolism. Through comprehensive analysis, we identified 21 genes that regulate metabolites, and qRT-PCR validation was conducted on six of these genes in both liver and kidney tissues. Additionally, XBJ demonstrated the capability to inhibit the activation of the NF-kB signaling pathway in both liver and kidney tissues, leading to a reduction in the occurrence of inflammatory responses. In summary, our study has validated the complexity of the natural compounds within XBJ and elucidated their potential mechanisms for addressing CLP-induced metabolic disturbances. This work contributes to our understanding of the bioactive compounds and their associated targets, providing insights into the potential molecular mechanisms involved.

Phosphorylation of insulin receptor substrates (IRS-1 and IRS-2) is attenuated following cecal ligation and puncture in mice

BACKGROUND

Sepsis is characterized as an insulin resistant state. However, the effects of sepsis on insulin's signal transduction pathway are unknown. The molecular activity driving insulin signaling is controlled by tyrosine phosphorylation of the insulin receptor β-subunit (IRβ) and of insulin receptor substrate molecules (IRS) -1 and IRS-2.

HYPOTHESIS

Cecal ligation and puncture (CLP) attenuates IRβ, IRS-1 and IRS-2 phosphorylation.

METHODS

IACUC-approved studies conformed to ARRIVE guidelines. CLP was performed on C57BL/6 mice; separate cohorts received intraperitoneal insulin at baseline (T0) or at 23 or 47 h. post-CLP, 1 h before mice were euthanized. We measured levels of (1) glucose and insulin in serum, (2) IRβ, IRS-1 and IRS-2 in skeletal muscle and liver homogenate and (3) phospho-Irβ (pIRβ) in liver and skeletal muscle, phospho-IRS-1 (pIRS-1) in skeletal muscle and pIRS-2 in liver. Statistical significance was determined using ANOVA with Sidak's post-hoc correction.

RESULTS

CLP did not affect the concentrations of IRβ, IRS-1or IRS-2 in muscle or liver homogenate or of IRS-1 in liver. Muscle IRS-1 concentration at 48 h. post-CLP was higher than at T0. Post-CLP pIRS-1 levels in muscle and pIRβ and pIRS-2 levels in liver were indistinguishable from T0 levels. At 48 h. post-CLP pIRβ levels in muscle were higher than at T0. Following insulin administration, the relative abundance of pIRβ in muscle and liver at T0 and at both post-CLP time points was significantly higher than abundance in untreated controls. In T0 controls, the relative abundance of pIRS-1 in muscle and of pIRS-2 in liver following insulin administration was higher than in untreated mice. However, at both post-CLP time points, the relative abundance of pIRS-1 in muscle and of pIRS-2 in liver following insulin administration was not distinguishable from the abundance in untreated mice at the same time point. Serum glucose concentration was significantly lower than T0 at 24 h., but not 48 h., post-CLP. Glucose concentration was lower following insulin administration to T0 mice but not in post-CLP animals. Serum insulin levels were significantly higher than baseline at both post-CLP time points.

CONCLUSIONS

CLP impaired insulin-induced tyrosine phosphorylation of both IRS-1 in muscle and IRS-2 in liver. These findings suggest that the molecular mechanism underlying CLP-induced insulin resistance involves impaired IRS-1/IRS-2 phosphorylation.

Prognostic significance of thyroid hormone T3 in patients with septic shock: a retrospective cohort study

Background

The role of thyroid hormones is crucial in the response to stress and critical illness, which has been reported to be closely associated with a poor prognosis in patients admitted to the intensive care unit (ICU). This study aimed to explore the relationship between thyroid hormone and prognosis in septic shock patients.

Methods

A total of 186 patients with septic shock were enrolled in the analytical study between December 2014 and September 2022. The baseline variables and thyroid hormone were collected. The patients were divided into survivor group and non-survivor group according to whether they died during the ICU hospitalization. Among 186 patients with septic shock, 123 (66.13%) were in the survivor group and 63 (33.87%) were in the non-survivor group.

Results

There were significant differences in the indictors of free triiodothyronine (FT3) (p = 0.000), triiodothyronine (T3) (p = 0.000), T3/FT3 (p = 0.000), acute physiology and chronic health evaluation II score (APACHE II) (p = 0.000), sequential organ failure assessment score (SOFA) (p = 0.000), pulse rate (p = 0.020), creatinine (p = 0.008), PaO2/FiO2 (p = 0.000), length of stay (p = 0.000) and hospitalization expenses (p = 0.000) in ICU between the two groups. FT3 [odds ratio (OR): 1.062, 95% confidence interval(CI): (0.021, 0.447), p = 0.003], T3 (OR: 0.291, 95% CI: 0.172-0.975, p = 0.037) and T3/FT3 (OR: 0.985, 95% CI:0.974-0.996, p = 0.006) were independent risk factors of the short-term prognosis of septic shock patients after adjustment. The areas under the receiver operating characteristic curves for T3 was associated with ICU mortality (AUC = 0.796, p < 0.05) and was higher than that for FT3 (AUC = 0.670, p < 0.05) and T3/FT3 (AUC = 0.712, p < 0.05). A Kaplan-Meier curve showed that patients with T3 greater than 0.48 nmol/L had a significantly higher survival rate than the patients with T3 less than 0.48 nmol/L.

Conclusions

The decrease in serum level of T3 in patients with septic shock is associated with ICU mortality. Early detection of serum T3 level could help clinicians to identify septic shock patients at high risk of clinical deterioration.

The role of hormones in sepsis: an integrated overview with a focus on mitochondrial and immune cell dysfunction

Sepsis is a dysregulated host response to infection that results in life-threatening organ dysfunction. Virtually every body system can be affected by this syndrome to greater or lesser extents. Gene transcription and downstream pathways are either up- or downregulated, albeit with considerable fluctuation over the course of the patient's illness. This multi-system complexity contributes to a pathophysiology that remains to be fully elucidated. Consequentially, little progress has been made to date in developing new outcome-improving therapeutics. Endocrine alterations are well characterised in sepsis with variations in circulating blood levels and/or receptor resistance. However, little attention has been paid to an integrated view of how these hormonal changes impact upon the development of organ dysfunction and recovery. Here, we present a narrative review describing the impact of the altered endocrine system on mitochondrial dysfunction and immune suppression, two interlinked and key aspects of sepsis pathophysiology.

The impact of hepatocyte-specific deletion of hypoxia-inducible factors on the development of polymicrobial sepsis with focus on GR and PPARα function

Introduction

Polymicrobial sepsis causes acute anorexia (loss of appetite), leading to lipolysis in white adipose tissue and proteolysis in muscle, and thus release of free fatty acids (FFAs), glycerol and gluconeogenic amino acids. Since hepatic peroxisome proliferator-activated receptor alpha (PPARα) and glucocorticoid receptor (GR) quickly lose function in sepsis, these metabolites accumulate (causing toxicity) and fail to yield energy-rich molecules such as ketone bodies (KBs) and glucose. The mechanism of PPARα and GR dysfunction is not known.

Methods &amp; results

We investigated the hypothesis that hypoxia and/or activation of hypoxia inducible factors (HIFs) might play a role in these issues with PPARα and GR. After cecal ligation and puncture (CLP) in mice, leading to lethal polymicrobial sepsis, bulk liver RNA sequencing illustrated the induction of the genes encoding HIF1α and HIF2α, and an enrichment of HIF-dependent gene signatures. Therefore, we generated hepatocyte-specific knock-out mice for HIF1α, HIF2α or both, and a new HRE-luciferase reporter mouse line. After CLP, these HRE-luciferase reporter mice show signals in several tissues, including the liver. Hydrodynamic injection of an HRE-luciferase reporter plasmid also led to (liver-specific) signals in hypoxia and CLP. Despite these encouraging data, however, hepatocyte-specific HIF1α and/or HIF2α knock-out mice suggest that survival after CLP was not dependent on the hepatocyte-specific presence of HIF proteins, which was supported by measuring blood levels of glucose, FFAs, and KBs. The HIF proteins were also irrelevant in the CLP-induced glucocorticoid resistance, but we found indications that the absence of HIF1α in hepatocytes causes less inactivation of PPARα transcriptional function.

Conclusion

We conclude that HIF1α and HIF2α are activated in hepatocytes in sepsis, but their contribution to the mechanisms leading to lethality are minimal.

Alterations in the gut microbiome and metabolome profiles of septic mice treated with Shen FuHuang formula

Sepsis has a high mortality rate, and treating sepsis remains a significant challenge worldwide. In former studies, our group found that traditional Chinese medicine, Shen FuHuang formula (SFH), is a promising medicine in treating coronavirus disease 2019 (COVID-19) patients with the septic syndrome. However, the underlying mechanisms remain elusive. In the present study, we first investigated the therapeutic effects of SFH on septic mice. To investigate the mechanisms of SFH-treated sepsis, we identified the gut microbiome profile and exploited untargeted metabolomics analyses. The results demonstrated that SFH significantly enhanced the mice’s 7-day survival rate and hindered the release of inflammatory mediators, i.e., TNF-α, IL-6, and IL-1β. 16S rDNA sequencing further deciphered that SFH decreased the proportion of Campylobacterota and Proteobacteria at the phylum level. LEfSe analysis revealed that the treatment of SFH enriched Blautia while decreased Escherichia_Shigella. Furthermore, serum untargeted metabolomics analysis indicated that SFH could regulate the glucagon signaling pathway, PPAR signaling pathway, galactose metabolism, and pyrimidine metabolism. Finally, we found the relative abundance of Bacteroides, Lachnospiraceae_NK4A136_group, Escherichia_Shigella, Blautia, Ruminococcus, and Prevotella were closely related to the enrichment of the metabolic signaling pathways, including L-tryptophan, uracil, glucuronic acid, protocatechuic acid, and gamma-Glutamylcysteine. In conclusion, our study demonstrated that SFH alleviated sepsis by suppressing the inflammatory response and hence reduced mortality. The mechanism of SFH for treating sepsis may be ascribed to the enrichment of beneficial gut flora and modulation in glucagon signaling pathway, PPAR signaling pathway, galactose metabolism, and pyrimidine metabolism. To sum up, these findings provide a new scientific perspective for the clinical application of SFH in treating sepsis.

Interleukin-6 promotes skeletal muscle catabolism by activating tryptophan-indoleamine 2,3-dioxygenase 1-kynurenine pathway during intra-abdominal sepsis

BACKGROUND

Inflammatory cytokine interleukin-6 (IL-6) plays a pivotal role in skeletal muscle degradation after intra-abdominal sepsis (IAS), with mechanism remained to be elucidated. Indoleamine 2,3-dioxygenase 1 (IDO-1), a key enzyme in converting tryptophan into kynurenine, could be activated by IL-6, and kynurenine has been shown to be involved in muscle degradation. We hypothesized that IL-6 could promote muscle degradation via tryptophan-IDO-1-kynurenine pathway in IAS patients.

METHODS

Serum and rectus abdominis (RA) were obtained from IAS or non-IAS patients. Mouse model of IAS-induced muscle wasting was generated by caecal ligation and puncture (CLP) and lipopolysaccharide (LPS) injection. IL-6 signalling was blocked by anti-mouse IL-6 antibody (IL-6-AB), and the IDO-1 pathway was blocked by navoximod. To elucidate the role of kynurenine in muscle mass and physiology, kynurenine was administered to IAS mice treated with IL-6-AB.

RESULTS

Compared to non-IAS patients, kynurenine levels in serum (+2.30-fold vs. non-IAS, P < 0.001) and RA (+3.11-fold vs. non-IAS, P < 0.001) were elevated, whereas tryptophan levels in serum (-53.65% vs. non-IAS, P < 0.01) and RA (-61.39% vs. non-IAS, P < 0.01) were decreased. Serum IL-6 level of the IAS group was significantly higher compared to non-IAS patients (+5.82-fold vs. non-IAS, P = 0.01), and muscle cross-sectional area (MCSA) was markedly reduced compared to non-IAS patients (-27.73% vs. non-IAS, P < 0.01). In animal experiments, IDO-1 expression was up-regulated in the small intestine, colon and blood for CLP or LPS-treated mice, and there was correlation (R²  = 0.66, P < 0.01) between serum and muscle kynurenine concentrations. Navoximod significantly mitigated IAS-induced skeletal muscle loss according to MCSA analysis (+22.94% vs. CLP, P < 0.05; +23.71% vs. LPS, P < 0.01) and increased the phosphorylated AKT (+2.15-fold vs. CLP, P < 0.01; +3.44-fold vs. LPS, P < 0.01) and myosin heavy chain (+3.64-fold vs. CLP, P < 0.01; +2.13-fold vs. LPS, P < 0.01) protein expression in myocytes. In the presence of anti-IL-6 antibody, a significantly decreased IDO-1 expression was observed in the small intestine, colon and blood in CLP or LPS mice (all P < 0.01), whereas the decrease of MCSA was alleviated (+37.43% vs. CLP + IgG, P < 0.001; +30.72% vs. LPS + IgG, P < 0.001). In contrast, additional supplementation of kynurenine decreased the MCSA in septic mice treated with IL-6-AB (both P < 0.01).

CONCLUSIONS

This study provided novel insights into the tryptophan-IDO-1-kynurenine-dependent mechanisms that underlie inflammatory cytokine-induced skeletal muscle catabolism during intra-abdominal sepsis.

Decreased circulating levels of free triiodothyronine in Sepsis children and correlation analysis

BACKGROUND

Intensive physical stress in sepsis can induce the disorder of endocrine function and impact the clinical course and prognosis. Low T3 syndrome has been verified to be the predictive indicator of poor prognosis in several researches. Reports on the influence factors of thyroid hormonal levels in children with severe sepsis are rare. We aim to investigate the thyroid hormonal variations in the course of sepsis and analyze that how to be affected by clinical data and inflammatory biomarkers.

METHODS

In the case-control study, 184 children with sepsis and 323 controls were included in Tongji Hospital, Wuhan, China, in 2019. Data on clinical and inflammatory parameters were collected from all participants. Circulating FT3(Free Triiodothyronine) levels were measured by Electrochemiluminescence immunoassay. Finally, we investigated the correlation between FT3 and related variables with linear regression analysis.

RESULTS

Serum FT3 was lower in the sepsis group than in control group(2.59 + 1.17 vs 2.83 + 1.01 pg/mL, p < 0.05). Significant moderately negative correlations(|r| > 0.3) of FT3 levels with ferritin, PCT, duration of symptoms, SOFA score, and mortality were revealed. Moreover, we observed that FT3 had the positive correlation with albumin, as well as white blood cell count.

CONCLUSIONS

Concentrations of serum FT3 are dramatically declined in sepsis children than in control children. Our results demonstrate that recognizing the potential abnormality of thyroid hormones in sepsis patients and examine timely through abnormal common clinical data and inflammatory biomarkers is a fine option.

Toxic-Induced Nonthyroidal Illness Syndrome Induced by Acute Low-Dose Pesticides Exposure-Preliminary In Vivo Study

BACKGROUND AND OBJECTIVES

Conditions such as trauma, burns, sepsis, or acute intoxications have considerable consequences on the endocrine status, causing "sick euthyroid syndrome". Organophosphate exposure may induce an increase in acetylcholine levels, thus altering the thyroid's hormonal status. The present study aims to identify the effects of acetylcholinesterase inhibition on thyroid hormones.

MATERIAL AND METHODS

A prospective experimental study was conducted on twenty Wistar rats. Blood samples were drawn to set baseline values for thyroid-stimulating hormone (TSH), triiodothyronine (T3), and thyroxine (T4). Chlorpyrifos 0.1 mg/kg was administered by oral gavage to induce acetyl-cholinesterase inhibition. After exhibiting cholinergic symptoms, blood samples were collected to assess levels of cholinesterase and thyroid hormones using ELISA.

RESULTS

Butyrylcholinesterase levels confirmed major inhibition immediately after intoxication compared to the baseline, certifying the intoxication. A significant increase in T4 levels was noted (p = 0.01) both at 2 h and 48 h after administration of organophosphate in sample rats. Similarly, T3 almost doubled its value 2 h after poisoning (4.2 ng/mL versus 2.5 ng/mL at baseline). Surprisingly, TSH displayed acute elevation with an afterward slow descending trend at 48 h (p = 0.1), reaching baseline value.

CONCLUSIONS

This study demonstrated that cholinesterase inhibition caused major alterations in thyroid hormone levels, which may be characterized by a transient hypothyroidism status with an impact on survival prognosis.

Interleukin-2 Transiently Inhibits Pulsatile Growth Hormone Secretion in Young but not Older Healthy Men

CONTEXT

Interleukin-2 (IL-2), a proinflammatory cytokine, has been used to treat malignancies. Increased cortisol and adrenocorticotropin (ACTH) were noted, but growth hormone (GH) secretion was not investigated in detail.

OBJECTIVE

We quantified GH secretion after a single subcutaneous injection of IL-2 in 17 young and 18 older healthy men in relation to dose, age, and body composition.

METHODS

This was a placebo-controlled, blinded, prospectively randomized, crossover study. At 20:00 hours IL-2 (3 or 6 million units/m2) or saline was injected subcutaneously. Lights were off between 23:00 and 07:00 hours. Blood was sampled at 10-minute intervals for 24 hours. Outcome measures included convolution analysis of GH secretion.

RESULTS

GH profiles were pulsatile under both experimental conditions and lower in older than young volunteers. Since the effect of IL-2 might be time limited, GH analyses were performed on the complete 24-hour series and the 6 hours after IL-2 administration. Total and pulsatile 24-hour GH secretion decreased nonsignificantly. Pulsatile secretion fell over the first 6 hours after IL-2 (P = .03), with visceral fat as a covariate (P = .003), but not age (P = .10). Plots of cumulative 2-hour bins of GH pulse mass showed a distinction by treatment and age groups: A temporary GH decrease of 32% and 28% occurred in the first 2-hour bins after midnight (P = .02 and .04) in young participants, whereas in older individuals no differences were present at any time point.

CONCLUSION

This study demonstrates that IL-2 temporarily diminishes GH secretion in young, but not older, men.

Combined glucocorticoid resistance and hyperlactatemia contributes to lethal shock in sepsis

Sepsis is a potentially lethal syndrome resulting from a maladaptive response to infection. Upon infection, glucocorticoids are produced as a part of the compensatory response to tolerate sepsis. This tolerance is, however, mitigated in sepsis due to a quickly induced glucocorticoid resistance at the level of the glucocorticoid receptor. Here, we show that defects in the glucocorticoid receptor signaling pathway aggravate sepsis pathophysiology by lowering lactate clearance and sensitizing mice to lactate-induced toxicity. The latter is exerted via an uncontrolled production of vascular endothelial growth factor, resulting in vascular leakage and collapse with severe hypotension, organ damage, and death, all being typical features of a lethal form of sepsis. In conclusion, sepsis leads to glucocorticoid receptor failure and hyperlactatemia, which collectively leads to a lethal vascular collapse.

Use of Organ Dysfunction as a Primary Outcome Variable Following Cecal Ligation and Puncture: Recommendations for Future Studies

Outcomes variables for research on sepsis have centered on mortality and changes in the host immune response. However, a recent task force (Sepsis-3) revised the definition of sepsis to "life-threatening organ dysfunction caused by a dysregulated host response to infection." This new definition suggests that human studies should focus on organ dysfunction. The appropriate criteria for organ dysfunction in either human sepsis or animal models are, however, poorly delineated, limiting the potential for translation. Further, in many systems, the difference between "dysfunction" and "injury" may not be clear. In this review, we identify criteria for organ dysfunction and/or injury in human sepsis and in rodents subjected to cecal ligation and puncture (CLP), the most commonly used animal model of sepsis. We further examine instances where overlap between human sepsis and CLP is sufficient to identify translational endpoints. Additional verification may demonstrate that these endpoints are applicable to other animals and to other sepsis models, for example, pneumonia. We believe that the use of these proposed measures of organ dysfunction will facilitate mechanistic studies on the pathobiology of sepsis and enhance our ability to develop animal model platforms to evaluate therapeutic approaches to human sepsis.

The Surviving Sepsis Campaign: research priorities for the administration, epidemiology, scoring and identification of sepsis

Objective

To identify priorities for administrative, epidemiologic and diagnostic research in sepsis.

Design

As a follow-up to a previous consensus statement about sepsis research, members of the Surviving Sepsis Campaign Research Committee, representing the European Society of Intensive Care Medicine and the Society of Critical Care Medicine addressed six questions regarding care delivery, epidemiology, organ dysfunction, screening, identification of septic shock, and information that can predict outcomes in sepsis.

Methods

Six questions from the Scoring/Identification and Administration sections of the original Research Priorities publication were explored in greater detail to better examine the knowledge gaps and rationales for questions that were previously identified through a consensus process.

Results

The document provides a framework for priorities in research to address the following questions: (1) What is the optimal model of delivering sepsis care?; (2) What is the epidemiology of sepsis susceptibility and response to treatment?; (3) What information identifies organ dysfunction?; (4) How can we screen for sepsis in various settings?; (5) How do we identify septic shock?; and (6) What in-hospital clinical information is associated with important outcomes in patients with sepsis?

Conclusions

There is substantial knowledge of sepsis epidemiology and ways to identify and treat sepsis patients, but many gaps remain. Areas of uncertainty identified in this manuscript can help prioritize initiatives to improve an understanding of individual patient and demographic heterogeneity with sepsis and septic shock, biomarkers and accurate patient identification, organ dysfunction, and ways to improve sepsis care.

Thyroid hormone disorders: a predictor of mortality in patients with septic shock defined by Sepsis-3?

Decreased serum thyroid hormone levels and their prediction of mortality in septic patients are still controversial, especially with the evolution of the definition of sepsis. This study aimed to assess the ability of thyroid hormone disorders to predict the early mortality of patients with septic shock defined by Sepsis-3. Sixty-three adult patients with septic shock admitted to a university hospital emergency intensive care unit (EICU) were studied. Serum free T3 (FT3), free T4 (FT4), thyroid stimulating hormone (TSH), C-reactive protein (CRP), procalcitonin (PCT), and lactate levels were determined and compared with survival status and organ dysfunction. Among the 63 patients studied, lower serum FT3 and FT4 levels were significantly associated with higher sequential organ failure assessment (SOFA) scores. Patients with septic shock with lower levels of FT3 (≤ 1.70 pmol/L) and FT4 (≤ 9.99 pmol/L) had significantly increased 28-day mortality. There was no significant difference in the serum TSH level between the survivor and nonsurvivor groups. The areas under the receiver operating characteristic curves for FT3 and FT4 levels were associated with 28-day mortality (0.92 and 0.89, respectively) and were higher than that for SOFA (0.82), CRP (0.65) and lactate (0.59). The decrease in serum levels of FT3 and FT4 in patients with septic shock is associated with the severity of organ dysfunction and 28-day mortality. Early detection of serum FT3 and FT4 levels could help clinicians to identify patients at high risk of clinical deterioration.

The Surviving Sepsis Campaign: Basic/Translational Science Research Priorities

Objectives:

Expound upon priorities for basic/translational science identified in a recent paper by a group of experts assigned by the Society of Critical Care Medicine and the European Society of Intensive Care Medicine.

Data Sources:

Original paper, search of the literature.

Study Selection:

By several members of the original task force with specific expertise in basic/translational science.

Data Extraction:

None.

Data Synthesis:

None.

Conclusions:

In the first of a series of follow-up reports to the original paper, several members of the original task force with specific expertise provided a more in-depth analysis of the five identified priorities directly related to basic/translational science. This analysis expounds on what is known about the question and what was identified as priorities for ongoing research. It is hoped that this analysis will aid the development of future research initiatives.

Sepsis as a Pan-Endocrine Illness-Endocrine Disorders in Septic Patients

Sepsis is defined as "life-threatening organ dysfunction caused by a dysregulated host response to infection". One of the elements of dysregulated host response is an endocrine system disorder. Changes in its functioning in the course of sepsis affect almost all hormonal axes. In sepsis, a function disturbance of the hypothalamic-pituitary-adrenal axis has been described, in the range of which the most important seems to be hypercortisolemia in the acute phase. Imbalance in the hypothalamic-pituitary-thyroid axis is also described. The most typical manifestation is a triiodothyronine concentration decrease and reverse triiodothyronine concentration increase. In the somatotropic axis, a change in the secretion pattern of growth hormone and peripheral resistance to this hormone has been described. In the hypothalamic-pituitary-gonadal axis, the reduction in testosterone concentration in men and the stress-induced "hypothalamic amenorrhea" in women have been described. Catecholamine and β-adrenergic stimulation disorders have also been reported. Disorders in the endocrine system are part of the "dysregulated host response to infection". They may also affect other components of this dysregulated response, such as metabolism. Hormonal changes occurring in the course of sepsis require further research, not only in order to explore their potential significance in therapy, but also due to their promising prognostic value.

PARP Inhibitors: An Innovative Approach to the Treatment of Inflammation and Metabolic Disorders in Sepsis

Sepsis is not only a threat to the health of individual patients but also presents a serious epidemiological problem. Despite intensive research, modern sepsis therapy remains based primarily on antimicrobial treatment and supporting the functions of failing organs. Finding a cure for sepsis represents a great and as yet unfulfilled need in modern medicine. Research results indicate that the activity of poly (adenosine diphosphate (ADP)-ribose) polymerase (PARP) may play an important role in the inflammatory response and the cellular metabolic disorders found in sepsis. Mechanisms by which PARP-1 may contribute to inflammation and metabolic disorders include effects on the regulation of gene expression, impaired metabolism, cell death, and the release of alarmins. These findings suggest that inhibition of this enzyme may be a promising solution for the treatment of sepsis. In studies using experimental sepsis models, inhibition of PARP-1 has been shown to ameliorate the inflammatory response and increase survival. This action was described, among others, for olaparib, a PARP-1 inhibitor approved for use in oncology. While the results of current research are promising, the use of PARP inhibitors in non-oncological diseases raises some concerns, mainly related to the enzyme's role in deoxyribonucleic acid (DNA) repair. However, the results of studies on experimental models indicate the effectiveness of even short-term PARP-1 inhibition and do not confirm concerns regarding its impact on the integrity of nuclear DNA. Current research presents PARP inhibition as a potential solution for the treatment of sepsis and indicates the need for further research.

Endogenous Glucose Production in Critical Illness

Regulation of endogenous glucose production (EGP) by hormonal, neuronal, and metabolic signaling pathways contributes to the maintenance of euglycemia under normal physiologic conditions. EGP is defined by the generation of glucose from substrates through glycogenolysis and gluconeogenesis, usually in fasted states, for local and systemic use. Abnormal increases in EGP are noted in patients with diabetes mellitus type 2, and elevated EGP may also impact the pathogenesis of nonalcoholic fatty liver disease and congestive heart failure. In this narrative review, we performed a literature search in PubMed to identify recently published English language articles characterizing EGP in critical illness. Evidence from preclinical and clinical studies demonstrates that critical illness can disrupt EGP through multiple mechanisms including increased systemic inflammation, counterregulatory hormone and catecholamine release, alterations in the hypothalamic-pituitary axis, insulin resistance, lactic acidosis, and iatrogenic insults such as vasopressors and glucocorticoids administered as part of clinical care. EGP contributes to hyperglycemia in critical illness when abnormally elevated and to hypoglycemia when abnormally depressed, each of which has been independently associated with increased mortality. Increased EGP may also promote protein catabolism that could worsen critical illness myopathy and impede recovery. Better understanding of the mechanisms and factors contributing to dysregulated EGP in critical illness may help in the development of therapeutic strategies that promote euglycemia, reduce intensive care unit-associated catabolism, and improve patient outcomes.

ENDOCRINE DISTURBANCES INDUCED BY LOW-DOSE ORGANOPHOSPHATE EXPOSURE IN MALE WISTAR RATS

BACKGROUND

Organophosphate exposure induces many endocrine effects.

AIM

In this study we observed the effects of acute stress induced by cholinesterase inhibition on the main hormonal axes.

MATERIALS AND METHODS

We included thirteen weanling Wistar rats that were subjected to organophosphate exposure. They were first tested for baseline levels of butyrylcholinesterase, cortisol, free triiodothyronine, thyroxine, thyroid-stimulating hormone and prolactin. Secondly, chlorpyrifos was administered. Next samples were taken to determine the level of all the above-mentioned parameters.

RESULTS

Butyrylcholinesterase was significantly decreased after exposure (p<0.001). Cortisol levels were significantly higher after clorpyrifos administration (358.75±43 vs. 241.2±35 nmoL/L)(p<0.01). Although prolactin had a growing trend (450.25±24.65 vs. 423±43.4 uI/mL), the results were not statistically significant. Both free triiodothyronine and thyroxine were significantly higher after exposure. Surprisingly, thyroid-stimulating hormone level almost doubled after exposure with high statistical significance (p<0.001), suggesting a central stimulation of thyroid axis. Butyrylcholinesterase level was proportional with thyroid-stimulating hormone level (p=0.02) and thyroxine level was inversely correlated to the cortisol level (p=0.01). Acute cholinesterase inhibition may induce high levels of cortisol, free triiodothyronine, thyroxine and thyroid-stimulating hormone. From our knowledge this is the first study dedicated to the assessment of acute changes of hormonal status in weanling animals after low-dose organophosphate exposure.Conclusion. Acute cholinesterase inhibition may cause acute phase hormonal disturbances specific to shocked patients.

Serum Amylase and Lipase for the Prediction of Pancreatic Injury in Critically Ill Children Admitted to the PICU

OBJECTIVES

Pancreatic injury is multifactorial and potentially devastating for critically ill children. We aimed to evaluate whether serum amylase and lipase among critically ill children could serve as an independent biomarker to predict pancreatic injury.

DESIGN

Retrospective cohort.

SETTING

PICU of a tertiary, pediatric medical center.

PATIENTS

Seventy-nine autopsies.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

A group of 79 children who died of different causes were investigated by autopsy. They were divided into pancreatic injury group and pancreatic noninjury group according to autopsy findings. Data based on patients' demographics, vital signs, laboratory findings, and clinical features at admission were collected and compared. Logistic regression was used to identify predictive factors for pancreatic injury. Receiver operating characteristic curve was constructed for assessing serum amylase and serum lipase to predicting pancreatic injury. Forty-one patients (51.9%) exhibited the pathologic changes of pancreatic injury. The levels of lactate, erythrocyte sedimentation rate, alanine transaminase, aspartate transaminase, and troponin-I in the injury group were significantly higher than that in the noninjury group, whereas the level of calcium was significantly lower than that in the noninjury group (p < 0.05). Multivariable logistic regression analysis showed that serum amylase, serum lipase, and septic shock were significantly associated with the occurrence rate of pancreatic injury. The statistically significant area under the curve results were as follows: serum amylase: area under the curve = 0.731, at a cutoff value of 97.5, sensitivity = 53.7, and specificity = 81.6; and serum lipase: area under the curve = 0.727, at a cutoff value of 61.1, sensitivity = 36.6, and specificity = 92.1.

CONCLUSIONS

Serum amylase and lipase could serve as independent biomarkers to predict pancreatic injury in critically ill children.

Effect on mortality of increasing the cutoff blood glucose concentration for initiating hypoglycaemia treatment in severely sick children aged 1 month to 5 years in Malawi (SugarFACT): a pragmatic, randomised controlled trial

BACKGROUND

Low blood glucose concentrations are common in sick children who present to hospital in low-resource settings and are associated with increased mortality. The cutoff blood glucose concentration for the diagnosis and treatment of hypoglycaemia currently recommended by WHO (2·5 mmol/L) is not evidence-based. We aimed to assess whether increasing the cutoff blood glucose concentration for hypoglycaemia treatment in severely ill children at presentation to hospital improves mortality outcomes.

METHODS

We did a pragmatic, randomised controlled trial at two referral hospitals in Malawi. Severely ill children aged 1 month to 5 years presenting to the emergency department with a capillary blood glucose concentration of between 2·5 mmol/L (3·0 mmol/L in severely malnourished children) and 5·0 mmol/L were randomly assigned (1:1) by a computer-generated randomisation sequence, stratified by study site and severe malnutrition, to receive either an immediate intravenous bolus of 10% dextrose at 5 mL/kg followed by a 24-h maintenance infusion of 10% dextrose at 100 mL/kg for the first 10 kg of bodyweight, 50 mL/kg for the next 10 kg, and 20 mL/kg for each subsequent kg of bodyweight (intervention group) or observation for a minimum of 60 min and standard care (control group). Participants and study personnel were not masked to treatment allocation. The primary outcome was all-cause in-hospital mortality, assessed on an intention-to-treat basis. Safety was also assessed in the intention-to-treat population. The study is registered with ClinicalTrials.gov, NCT02989675.

FINDINGS

Between Dec 5, 2016, and Jan 22, 2019, 10 947 children were screened, of whom 332 were randomly assigned, and 322 were included in the final analysis (n=162 in the control group and n=160 in the intervention group). The study was terminated after an interim analysis at 24% enrolment indicated futility. The median age of participants was 2·3 years (IQR 1·4-3·2), 65 (45%) were female, and the baseline characteristics of participants were similar between the two groups. The number of in-hospital deaths from any cause was 26 (16%) in the control group and 24 (15%) in the intervention group, with an absolute mortality difference of 1·0% (95% CI -6·9 to 9·0). Serious adverse events, including hypoglycaemia, hyperglycaemia, convulsions, reduced consciousness, and death, were reported in 47 (29%) children in the control group and 39 (24%) children in the intervention group.

INTERPRETATION

Increasing the cutoff blood glucose concentration for hypoglycaemia treatment in severely sick children in Malawi from 2·5 mmol/L to 5·0 mmol/L did not reduce all-cause in-hospital mortality. Our findings do not support changing the cutoff for dextrose administration, and further research on the optimal management of severely ill children who present to the emergency department with low blood glucose concentrations is warranted.

FUNDING

Swedish Research Council and Stockholm Country Council.

Sepsis-associated encephalopathy and septic encephalitis: an update

INTRODUCTION

Sepsis-associated encephalopathy (SAE) and septic encephalitis (SE) are associated with increased mortality, long-term cognitive impairment, and focal neurological deficits.

AREAS COVERED

The PUBMED database was searched 2016-2020. The clinical manifestation of SAE is delirium, SE additionally is characterized by focal neurological symptoms. SAE is caused by inflammation with endothelial/microglial activation, increase of permeability of the blood-brain-barrier, hypoxia, imbalance of neurotransmitters, glial activation, axonal, and neuronal loss. Septic-embolic (SEE) and septic-metastatic encephalitis (SME) are characterized by focal ischemia (SEE) and small abscesses (SME). The continuum between SAE, SME, and SEE is documented by imaging techniques and autopsies. The backbone of treatment is rapid optimum antibiotic therapy. Experimental approaches focus on modulation of inflammation, stabilization of the blood-brain barrier, and restoration of membrane/mitochondrial function.

EXPERT OPINION

The most promising diagnostic approaches are new imaging techniques. The most important measure to fight delirium remains establishment of daily structure and adequate sensory stimuli. Dexmedetomidine and melatonin appear to reduce the frequency of delirium, their efficacy in SAE and SE remains to be established. Drugs already licensed for other indications or available as food supplements which may be effective in SAE are statins, L-DOPA/benserazide, β-hydroxybutyrate, palmitoylethanolamide, and tetracyclines or other bactericidal non-lytic antibiotics.

Impaired angiotensin II type 1 receptor signaling contributes to sepsis-induced acute kidney injury

In sepsis-induced acute kidney injury, kidney blood flow may increase despite decreased glomerular filtration. Normally, angiotensin-II reduces kidney blood flow to maintain filtration. We hypothesized that sepsis reduces angiotensin type-1 receptor (AT1R) expression to account for this observation and tested this hypothesis in a patient case-control study and studies in mice. Seventy-three mice underwent cecal ligation and puncture (a sepsis model) or sham operation. Additionally, 94 septic mice received losartan (selective AT1R antagonist), angiotensin II without or with losartan, or vehicle. Cumulative urine output, kidney blood flow, blood urea nitrogen, and creatinine were measured. AT1R expression was assessed using ELISA, qPCR, and immunofluorescence. A blinded pathologist evaluated tissue for ischemic injury. AT1R expression was compared in autopsy tissue from seven patients with sepsis to that of the non-involved portion of kidney from ten individuals with kidney cancer and three non-infected but critically ill patients. By six hours post ligation/puncture, kidney blood flow doubled, blood urea nitrogen rose, and urine output fell. Concurrently, AT1R expression significantly fell 2-fold in arterioles and the macula densa. Creatinine significantly rose by 24 hours and sham operation did not alter measurements. Losartan significantly exacerbated ligation/puncture-induced changes in kidney blood flow, blood urea nitrogen, creatinine, and urine output. There was no histologic evidence of cortical ischemia. Significantly, angiotensin II prevented changes in kidney blood flow, creatinine, and urine output compared to vehicle. Co-administering losartan with angiotensin-II reversed this protection. Relative to both controls, patients with sepsis had low AT1R expression in arterioles and macula densa. Thus, murine cecal ligation/puncture and clinical sepsis decrease renal AT1R expression. Angiotensin II prevents functional changes while AT1R-blockade exacerbates them independent of ischemia in mice.

The surviving sepsis campaign: basic/translational science research priorities

Objectives

Expound upon priorities for basic/translational science identified in a recent paper by a group of experts assigned by the Society of Critical Care Medicine and the European Society of Intensive Care Medicine.

Data sources

Original paper, search of the literature.

Study selection

This study is selected by several members of the original task force with specific expertise in basic/translational science. Data extraction and data synthesis are not available.

Conclusions

In the first of a series of follow-up reports to the original paper, several members of the original task force with specific expertise provided a more in-depth analysis of the five identified priorities directly related to basic/translational science. This analysis expounds on what is known about the question and what was identified as priorities for ongoing research. It is hoped that this analysis will aid the development of future research initiatives.

Sepsis therapies: learning from 30 years of failure of translational research to propose new leads

Sepsis has been identified by the World Health Organization (WHO) as a global health priority. There has been a tremendous effort to decipher underlying mechanisms responsible for organ failure and death, and to develop new treatments. Despite saving thousands of animals over the last three decades in multiple preclinical studies, no new effective drug has emerged that has clearly improved patient outcomes. In the present review, we analyze the reasons for this failure, focusing on the inclusion of inappropriate patients and the use of irrelevant animal models. We advocate against repeating the same mistakes and propose changes to the research paradigm. We discuss the long-term consequences of surviving sepsis and, finally, list some putative approaches-both old and new-that could help save lives and improve survivorship.

Does Helium Pneumoperitoneum Reduce the Hyperinflammatory Response in Septic Animals during Laparoscopy?

Background/Aim. An exacerbated reaction to peritoneal infection and attendant surgical procedures is characterized by an intense hyperinflammatory state, the magnitude of which is proportional to the severity of tissue injury. Laparoscopy generates lower levels of tissue damage compared with open surgery and should induce less pronounced immune responses. The aim of this study was to determine whether laparoscopy assisted by helium rather than carbon dioxide pneumoperitoneum would induce an attenuated inflammatory state in septic animals. Materials and Methods. Thirty-two Wistar rats were divided randomly into four equal groups, two of which were submitted to carbon dioxide or helium pneumoperitoneum-assisted laparoscopic cecal ligation and puncture (CLP) induced sepsis and subsequent abdominal lavage. Two control groups were submitted to identical laparoscopic procedures with carbon dioxide or helium as insufflator gas but without CLP. After 24 hours, serum levels of tumor necrosis factor alpha (TNF-α), interleukins 1 and 6 (IL-1 and IL-6, respectively), and cortisol were determined.

Usefulness of the Geriatric Nutritional Risk Index to predict the severity of cholecystitis among older patients in the emergency department

AIM

We sought to investigate whether the Geriatric Nutritional Risk Index is associated with systemic organ dysfunction among older patients who present with cholecystitis to the emergency department.

METHODS

This was an observational retrospective study among consecutive older patients with cholecystitis in the emergency department from 2012 to 2018. We collected baseline characteristics and laboratory data, and re-categorized the Geriatric Nutritional Risk Index into three risk groups. We carried out univariate and multivariate analyses to identify factors associated with systemic organ dysfunction. Logistic regression was used for statistical analysis.

RESULTS

A total of 303 patients were included in this study. The median age of participants was 74 years (interquartile range 68-79 years). The overall proportion of systemic organ dysfunction was 26.4%. The Geriatric Nutritional Risk Index was stratified as: ≥98 (n = 183, systemic organ dysfunction 15.3%), 87 to <98 (n = 90, systemic organ dysfunction 38.9%) and <87 (n = 30, systemic organ dysfunction 56.7%). Multivariate analysis using a logistic regression model showed that age, respiratory rate, temperature, geriatric nutritional risk index and quick Sepsis-related Organ Failure Assessment score in the emergency department were independently associated with systemic organ dysfunction in patients with cholecystitis.

CONCLUSIONS

The Geriatric Nutritional Risk Index was recognized as an independent factor associated with systemic organ dysfunction in older patients in the emergency department who presented with cholecystitis. This index might be helpful in screening patient risk and deciding whether to carry out further tests. Geriatr Gerontol Int 2020; 20: 455-460.

Sepsis: From Historical Aspects to Novel Vistas. Pathogenic and Therapeutic Considerations

BACKGROUND

Sepsis is a clinical condition due to an infectious event which leads to an early hyper-inflammatory phase followed by a status of tolerance or immune paralysis. Hyper-inflammation derives from a massive activation of immune (neutrophils, monocytes/macrophages, dendritic cells and lymphocytes) and non-immune cells (platelets and endothelial cells) in response to Gram-negative and Gram-positive bacteria and fungi.

DISCUSSION

A storm of pro-inflammatory cytokines and reactive oxygen species accounts for the systemic inflammatory response syndrome. In this phase, bacterial clearance may be associated with a severe organ failure development. Tolerance or compensatory anti-inflammatory response syndrome (CARS) depends on the production of anti-inflammatory mediators, such as interleukin-10, secreted by T regulatory cells. However, once triggered, CARS, if prolonged, may also be detrimental to the host, thus reducing bacterial clearance.

CONCLUSION

In this review, the description of pathogenic mechanisms of sepsis is propaedeutic to the illustration of novel therapeutic attempts for the prevention or attenuation of experimental sepsis as well as of clinical trials. In this direction, inhibitors of NF-κB pathway, cell therapy and use of dietary products in sepsis will be described in detail.

The Role of Adipose Tissue and Adipokines in Sepsis: Inflammatory and Metabolic Considerations, and the Obesity Paradox

PURPOSE

Sepsis has become a global health problem with rising incidence and high mortality, creating a substantial social and economic burden. Early diagnosis and treatment can improve outcome, but reliable sepsis biomarkers are lacking. This review summarizes current evidence of the pathophysiological mechanisms linking adipose tissue to sepsis and presents experimental and clinical data on adipokines and sepsis along with important insights into the obesity paradox in sepsis survival.

RECENT FINDINGS

Sepsis is characterized by significant alterations in circulating cytokines and adipokines, biologically active molecules produced by the adipose tissue, being implicated in metabolic and inflammatory processes. Although data are inconclusive regarding classic adipokines such as leptin and adiponectin, recent evidence have highlighted the striking elevation of resistin and visfatin in critical illness and sepsis as well as their association with sepsis severity and outcomes. Given that inflammatory and metabolic pathways are involved in sepsis, studying adipokines presents an attractive, innovative, and promising research field that may provide more powerful diagnostic and prognostic biomarkers as well as novel therapeutic targets, empowering the therapeutic armamentarium for sepsis management in order to improve survival.

Critical Roles of Endogenous Glucocorticoids for Disease Tolerance in Malaria

During malaria, the hypothalamic-pituitary-adrenal (HPA) axis is activated and glucocorticoid (GC) levels are increased, but their essential roles have been largely overlooked. GCs are decisive for systemic regulation of vital processes such as immune responses, vascular function, and metabolism, which are crucial in malaria. Here, we introduce GCs in general, followed by their versatile roles for disease tolerance in malaria. A complementary comparison is provided with their role in sepsis. Finally, potential translational implications are considered. The failed clinical trials of dexamethasone against cerebral malaria in the past have diminished the interest in GCs in malaria. However, the issue of relative corticosteroid insufficiency has barely been explored in malaria patients, but may hold promise for a better understanding and treatment of specific malaria complications.

Surviving Sepsis Campaign: Research Priorities for Sepsis and Septic Shock

OBJECTIVE

To identify research priorities in the management, epidemiology, outcome and underlying causes of sepsis and septic shock.

DESIGN

A consensus committee of 16 international experts representing the European Society of Intensive Care Medicine and Society of Critical Care Medicine was convened at the annual meetings of both societies. Subgroups had teleconference and electronic-based discussion. The entire committee iteratively developed the entire document and recommendations.

METHODS

Each committee member independently gave their top five priorities for sepsis research. A total of 88 suggestions (Supplemental Table 1, Supplemental Digital Content 2, http://links.lww.com/CCM/D636) were grouped into categories by the committee co-chairs, leading to the formation of seven subgroups: infection, fluids and vasoactive agents, adjunctive therapy, administration/epidemiology, scoring/identification, post-intensive care unit, and basic/translational science. Each subgroup had teleconferences to go over each priority followed by formal voting within each subgroup. The entire committee also voted on top priorities across all subgroups except for basic/translational science.

RESULTS

The Surviving Sepsis Research Committee provides 26 priorities for sepsis and septic shock. Of these, the top six clinical priorities were identified and include the following questions: 1) can targeted/personalized/precision medicine approaches determine which therapies will work for which patients at which times?; 2) what are ideal endpoints for volume resuscitation and how should volume resuscitation be titrated?; 3) should rapid diagnostic tests be implemented in clinical practice?; 4) should empiric antibiotic combination therapy be used in sepsis or septic shock?; 5) what are the predictors of sepsis long-term morbidity and mortality?; and 6) what information identifies organ dysfunction?

CONCLUSIONS

While the Surviving Sepsis Campaign guidelines give multiple recommendations on the treatment of sepsis, significant knowledge gaps remain, both in bedside issues directly applicable to clinicians, as well as understanding the fundamental mechanisms underlying the development and progression of sepsis. The priorities identified represent a roadmap for research in sepsis and septic shock.

Evidence-based updates to the 2016 Surviving Sepsis Guidelines and clinical implications

Despite numerous advances in understanding the pathophysiology of sepsis and its treatment, sepsis morbidity and mortality remain high. The 2016 Surviving Sepsis Campaign guidelines incorporated the latest research to formulate new sepsis diagnoses and updated treatment recommendations. This article reviews how to manage patients with sepsis and provides insight into the 2016 guidelines, updates, and suggestions.

Surviving sepsis campaign: research priorities for sepsis and septic shock

Objective

To identify research priorities in the management, epidemiology, outcome and underlying causes of sepsis and septic shock.

Design

A consensus committee of 16 international experts representing the European Society of Intensive Care Medicine and Society of Critical Care Medicine was convened at the annual meetings of both societies. Subgroups had teleconference and electronic-based discussion. The entire committee iteratively developed the entire document and recommendations.

Methods

Each committee member independently gave their top five priorities for sepsis research. A total of 88 suggestions (ESM 1 - supplemental table 1) were grouped into categories by the committee co-chairs, leading to the formation of seven subgroups: infection, fluids and vasoactive agents, adjunctive therapy, administration/epidemiology, scoring/identification, post-intensive care unit, and basic/translational science. Each subgroup had teleconferences to go over each priority followed by formal voting within each subgroup. The entire committee also voted on top priorities across all subgroups except for basic/translational science.

Results

The Surviving Sepsis Research Committee provides 26 priorities for sepsis and septic shock. Of these, the top six clinical priorities were identified and include the following questions: (1) can targeted/personalized/precision medicine approaches determine which therapies will work for which patients at which times?; (2) what are ideal endpoints for volume resuscitation and how should volume resuscitation be titrated?; (3) should rapid diagnostic tests be implemented in clinical practice?; (4) should empiric antibiotic combination therapy be used in sepsis or septic shock?; (5) what are the predictors of sepsis long-term morbidity and mortality?; and (6) what information identifies organ dysfunction?

Conclusions

While the Surviving Sepsis Campaign guidelines give multiple recommendations on the treatment of sepsis, significant knowledge gaps remain, both in bedside issues directly applicable to clinicians, as well as understanding the fundamental mechanisms underlying the development and progression of sepsis. The priorities identified represent a roadmap for research in sepsis and septic shock.

Electronic supplementary material

The online version of this article (10.1007/s00134-018-5175-z) contains supplementary material, which is available to authorized users.