Is worsening multiple organ failure the cause of death in patients with severe sepsis?

Improvement in ICU Mortality From Sepsis Associated With Recuperation From Septic Multiple-Organ Failure: A Retrospective, Single-Center, Cohort Study

BACKGROUND

Although mortality due to sepsis has decreased in recent decades, there are few studies on the timing of death during ICU stay. Characteristics of patients related to changes over the years of ICU death and changes in the timing of ICU death will provide new insights for future sepsis management.

METHODS

This was a single-center, retrospective study. Patients admitted to the ICU for sepsis between 2005 and 2019 were included in the study. The study period was divided into three five-year intervals, and the timing of death in the ICU was divided into early-stage (1-3 ICU days), mid-stage (4-14 ICU days), and late-stage (15 or more ICU days). Patient characteristics related to ICU death at three five-year intervals and the timing of death were evaluated.

RESULTS

ICU mortality for sepsis has decreased over time (2005-2009, 30.2%; 2010-2014, 21.0%; 2015-2019, 12.1%; p<0.01). In the timing of death, only mid-stage mortality decreased. Multiple-organ failure (OR, 4.53; 95% CI, 2.79-7.48) and hematological malignancies (OR, 2.48; 95% CI, 1.19-5.07) were associated with ICU mortality over entire study periods. Only multiple-organ failure was associated with ICU mortality at the five-year intervals (OR, 5.94; 95% CI, 2.73-13.7 for 2005-2009; OR, 4.01; 95% CI, 1.82-9.31 for 2010-2014; OR, 2.58; 95% CI, 1.05-6.59 for 2015-2019). Mid-stage mortality of multiple-organ failure decreased (2005-2009, 12.8%; 2010-2014, 7.6%; 2015-2019, 1.6%; p=0.02). However, early- and late-stage mortality of multiple-organ failure did not change.

CONCLUSIONS

Improvement in mid-stage mortality in septic patients with multiple-organ failure can contribute to the improvement of overall ICU mortality in patients with sepsis.

Mortality of in-hospital cardiac arrest among patients with and without preceding sepsis: A national inpatient sample analysis

INTRODUCTION

The impact of preceding sepsis on in-hospital cardiac arrest (IHCA)-related mortality has not been established. This study aimed to determine the association between IHCA-related mortality and sepsis.

METHODS

This retrospective study used the National Inpatient Sample data from 01/2017 to 12/2019. The study included adults (≥18 years) who suffered from IHCA. The study classified cardiac arrest rhythms as ventricular tachycardia/ventricular fibrillation or pulseless electronic activity/asystole. We compared the IHCA-related in-hospital mortality between sepsis and non-sepsis groups in all patients and subgroups divided by cardiac arrest rhythm and age. Multivariable logistic regression analysis was performed to assess the independent association between sepsis and in-hospital mortality.

RESULTS

A total of 357,850 hospitalizations who suffered from IHCA were identified, with sepsis present in 17.6% of patients. IHCA-related in-hospital mortality was 84.8% in sepsis and 68.4% in non-sepsis-related hospitalizations (p < 0.001). IHCA-related in-hospital mortality was higher in sepsis than in non-sepsis groups, regardless of age or cardiac arrest rhythms. In multivariable logistic regression analysis, sepsis was significantly associated with higher mortality with an odds ratio of 2.27 (95% confidence interval: 2.07-2.50, p < 0.001).

CONCLUSION

Sepsis was associated with higher in-hospital cardiac arrest mortality compared to non-sepsis cases, regardless of age and cardiac rhythm.

Pannexin1: insight into inflammatory conditions and its potential involvement in multiple organ dysfunction syndrome

Sepsis represents a global health concern, and patients with severe sepsis are at risk of experiencing MODS (multiple organ dysfunction syndrome), which is associated with elevated mortality rates and a poorer prognosis. The development of sepsis involves hyperactive inflammation, immune disorder, and disrupted microcirculation. It is crucial to identify targets within these processes to develop therapeutic interventions. One such potential target is Panx1 (pannexin-1), a widely expressed transmembrane protein that facilitates the passage of molecules smaller than 1 KDa, such as ATP. Accumulating evidence has implicated the involvement of Panx1 in sepsis-associated MODS. It attracts immune cells via the purinergic signaling pathway, mediates immune responses via the Panx1-IL-33 axis, promotes immune cell apoptosis, regulates blood flow by modulating VSMCs' and vascular endothelial cells' tension, and disrupts microcirculation by elevating endothelial permeability and promoting microthrombosis. At the level of organs, Panx1 contributes to inflammatory injury in multiple organs. Panx1 primarily exacerbates injury and hinders recovery, making it a potential target for sepsis-induced MODS. While no drugs have been developed explicitly against Panx1, some compounds that inhibit Panx1 hemichannels have been used extensively in experiments. However, given that Panx1's role may vary during different phases of sepsis, more investigations are required before interventions against Panx1 can be applied in clinical. Overall, Panx1 may be a promising target for sepsis-induced MODS. Nevertheless, further research is needed to understand its complex role in different stages of sepsis fully and to develop suitable pharmaceutical interventions for clinical use.

Dose-specific efficacy of adipose-derived mesenchymal stem cells in septic mice

BACKGROUND

Mesenchymal stem cells (MSCs) therapy for sepsis has been extensively studied in the past decade; however, the treatment regimen and mechanism of action of MSCs remain elusive. Here, we attempted to understand the efficacy and mechanism of action of MSCs on rescuing mice with sepsis.

METHODS

A mouse model of sepsis was produced by cecal ligation and puncture (CLP). Allogeneic adipose-derived MSCs (ADSCs) were administered by intravenous infusion at 6 h after CLP, and dose-related effects of ADSCs on these mice were determined by survival rate, histopathological changes, biochemical and coagulation parameters, bacterial load, and plasma levels of endotoxin and inflammatory cytokines. The tissue distribution of intravenously infused ADSCs in septic mice was investigated by pre-labeling ADSCs with the lipophilic membrane dye PKH26. RNA sequencing analysis was performed to assess the transcriptional changes in peripheral blood mononuclear cells (PBMCs) and the liver.

RESULTS

A significant therapeutic effect of ADSCs at a dose of 2 × 10⁷ cells/kg in septic mice was evidenced by a remarkable reduction in mortality (35.89% vs. 8.89% survival rate), blood bacterial burden, systemic inflammation, and multiple organ damage. In contrast, ADSCs at a lower dose (1 × 10⁷ cells/kg) failed to achieve any beneficial outcomes, while ADSCs at a higher dose (4 × 10⁷ cells/kg) caused more early death within 24 h after CLP, retaining a steady survival rate of 21.42% thereafter. PKH26-labeled ADSCs were predominantly localized in the lungs of septic mice after intravenous infusion, with only a smaller proportion of PKH26-positive signals appearing in the liver and spleen. RNA sequencing analysis identified that insufficient phagocytic activity of PBMCs in addition to a hyperactivation of the hepatic immune response was responsible for the ineffectiveness of low-dose ADSCs therapy, and acute death caused by high-dose ADSCs infusion was associated with impaired coagulation signaling in PBMCs and exacerbated hepatic hypoxic injury.

CONCLUSIONS

Our findings demonstrate a dose-specific effect of ADSCs on the treatment of sepsis due to dose-related interactions between exogenous stem cells and the host's microenvironment. Therefore, a precise dosing regimen is a prerequisite for ADSCs therapy for sepsis.

Sex differences in cardiovascular response to sepsis

Recently, there has been increased recognition of the importance of sex as a biological factor affecting disease and health. Many preclinical studies have suggested that males may experience a less favorable outcome in response to sepsis than females. The underlying mechanisms for these differences are still largely unknown but are thought to be related to the beneficial effects of estrogen. Furthermore, the immunosuppressive role of testosterone is also thought to contribute to the sex-dependent differences that are present in clinical sepsis. There are still significant knowledge gaps in this field. This mini-review will provide a brief overview of sex-dependent variables in relation to sepsis and the cardiovascular system. Preclinical animal models for sepsis research will also be discussed. The intent of this mini-review is to inspire interest for future considerations of sex-related variables in sepsis that should be addressed to increase our understanding of the underlying mechanisms in sepsis-induced cardiovascular dysfunction for the identification of therapeutic targets and improved sepsis management and treatment.

Association between Mortality and Sequential Organ Failure Assessment Score during a Short Stay in the Intensive Care Unit after Non-Cardiac Surgery

Background: The sequential organ failure assessment (SOFA) score has been validated in various clinical situations. However, it has not been investigated during a short stay in the intensive care unit (ICU). This study aimed to evaluate the association between the SOFA score and outcomes in patients who were monitored for less than one day after non-cardiac surgery. Methods: From a total of 203,787 consecutive adult patients who underwent non-cardiac surgery between January 2011 and June 2019, we selected 17,714 who were transferred to the ICU immediately after surgery and stayed for less than 24 h. Patients were divided according to quartile value and change between the initial and follow-up levels of SOFA score. Results: Three-year mortality tended to increase with a higher initial SOFA score (11.7%, 11.8%, 15.1%, and 17.8%, respectively). The patients were divided according to changes in the SOFA score at the midnight postoperative follow-up check: 16,176 (91.3%) in the stable group and 1538 (8.7%) in the worsened group. The worsened group showed significantly higher three-year mortality and complications (13.2% vs. 18.6%; HR [hazard ratio]: 1.236; 95% CI [confidence interval]: 1.108−1.402; p ≤ 0.0021 for three-year mortality and 3.8% vs. 9.1%; HR: 2.13; 95% CI: 1.73−2.60; p < 0.001 for acute kidney injury). Conclusions: The SOFA score during a short stay in the ICU after non-cardiac surgery showed an association with mortality. The change in SOFA score may need to be considered at discharge from the ICU.

Outcomes Associated With Timing of Neurologic Dysfunction Onset Relative to Pediatric Sepsis Recognition

OBJECTIVES

To compare outcomes associated with timing-early versus late-of any neurologic dysfunction during pediatric sepsis.

DESIGN

Secondary analysis of a cross-sectional point prevalence study.

SETTING

A total of 128 PICUs in 26 countries.

PATIENTS

Less than 18 years with severe sepsis on 5 separate days (2013-2014).

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Patients were categorized as having either no neurologic dysfunction or neurologic dysfunction (i.e., present at or after sepsis recognition), which was defined as Glasgow Coma Scale score less than 5 and/or fixed dilated pupils. Our primary outcome was death or new moderate disability (i.e., Pediatric Overall [or Cerebral] Performance Category score ≥3 and change ≥1 from baseline) at hospital discharge, and 87 of 567 severe sepsis patients (15%) had neurologic dysfunction within 7 days of sepsis recognition (61 at sepsis recognition and 26 after sepsis recognition). Primary site of infection varied based on presence of neurologic dysfunction. Death or new moderate disability occurred in 161 of 480 (34%) without neurologic dysfunction, 45 of 61 (74%) with neurologic dysfunction at sepsis recognition, and 21 of 26 (81%) with neurologic dysfunction after sepsis recognition (p < 0.001 across all groups). On multivariable analysis, in comparison with those without neurologic dysfunction, neurologic dysfunction whether at sepsis recognition or after was associated with increased odds of death or new moderate disability (adjusted odds ratio, 4.9 [95% CI, 2.3-10.1] and 10.7 [95% CI, 3.8-30.5], respectively). We failed to identify a difference between these adjusted odds ratios of death or new moderate disability that would indicate a differential risk of outcome based on timing of neurologic dysfunction (p = 0.20).

CONCLUSIONS

In this severe sepsis international cohort, the presence of neurologic dysfunction during sepsis is associated with worse outcomes at hospital discharge. The impact of early versus late onset of neurologic dysfunction in sepsis on outcome remains unknown, and further work is needed to better understand timing of neurologic dysfunction onset in pediatric sepsis.

Plasma syndecan‐1 concentration as a biomarker for endothelial glycocalyx degradation in septic adult horses

BACKGROUND

Limited information is available regarding endothelial glycocalyx degradation during sepsis in horses. Plasma syndecan-1 concentrations are increased in consequence of sepsis in other species and have been useful for prognostication.

OBJECTIVES

To determine whether plasma syndecan-1 levels are increased in adult horses affected with sepsis.

STUDY DESIGN

Retrospective cohort study.

METHODS

Adult horses were assigned to one of three groups based on results of physical and laboratory examinations, clinical diagnosis, and results of previously described SIRS classification: Group 1 horses included healthy, nonseptic horses; Group 2 included horses in which clinical illness was identified but that were not considered to be septic; Group 3 included horses with a clinical diagnosis of sepsis. Plasma syndecan-1 concentration was determined in blood obtained at admission into the hospital for each horse, using an equine specific ELISA. Data were analysed using ANOVA and linear regression (p ≤ 0.05).

RESULTS

One hundred and ninety-one horses were included and divided into three groups. Scores for SIRS were highest for Group 3 horses and lowest in Groups 1 and 2. Plasma syndecan-1 concentrations in Group 3 horses (50.73 ± 84.24 μg/ml; n = 42) were greater than those for Group 1 (15.69 ± 11.28 μg/ml; n = 66) and Group 2 (16.88 ± 15.30 μg/ml; n = 83). There was no difference regarding syndecan concentrations between Groups 1 and 2.

MAIN LIMITATIONS

Retrospective study design, solitary time point of measurement for each patient, and lack of a widely accepted consensus regarding definitive diagnosis of sepsis in adult horses.

CONCLUSIONS

Circulating plasma levels of syndecan-1, a biochemical marker of endothelial glycocalyx damage, are increased in septic adult horses.

Tertiary peritonitis: considerations for complex team-based care

Peritonitis, as a major consequence of hollow visceral perforation, anastomotic disruption, ischemic necrosis, or other injuries of the gastrointestinal tract, often drives acute care in the emergency department, operating room, and the ICU. Chronic critical illness (CCI) represents a devastating challenge in modern surgical critical care where successful interventions have fostered a growing cohort of patients with prolonged dependence on mechanical ventilation and other organ supportive therapies who would previously have succumbed much earlier in the acute phase of critical illness. An important subset of CCI patients are those who have survived an emergency abdominal operation, but who subsequently require prolonged open abdomen management complicated by persistent peritoneal space infection or colonization, fistula formation, and gastrointestinal (GI) tract dysfunction; these patients are described as having tertiary peritonitis (TP).The organ dysfunction cascade in TP terminates in death in between 30 and 64% of patients. This narrative review describes key-but not all-elements in a framework for the coordinate multiprofessional team-based management of a patient with tertiary peritonitis to mitigate this risk of death and promote recovery. Given the prolonged critical illness course of this unique patient population, early and recurrent Palliative Care Medicine consultation helps establish goals of care, support adjustment to changes in life circumstance, and enable patient and family centered care.

Exosomes from Human Placenta Choriodecidual Membrane-Derived Mesenchymal Stem Cells Mitigate Endoplasmic Reticulum Stress, Inflammation, and Lung Injury in Lipopolysaccharide-Treated Obese Mice

Endoplasmic reticulum (ER) stress mediates the effects of obesity on aggravating sepsis-induced lung injury. We investigated whether exosomes from human placenta choriodecidual membrane-derived mesenchymal stem cells (pcMSCs) can mitigate pulmonary ER stress, lung injury, and the mechanisms of inflammation, oxidation, and apoptosis in lipopolysaccharide-treated obese mice. Diet-induced obese (DIO) mice (adult male C57BL/6J mice fed with a 12-week high-fat diet) received lipopolysaccharide (10 mg/kg, i.p.; DIOLPS group) or lipopolysaccharide plus exosomes (1 × 108 particles/mouse, i.p.; DIOLPSExo group). Our data demonstrated lower levels of ER stress (upregulation of glucose-regulated protein 78, phosphorylated eukaryotic initiation factor 2α, and C/EBP homologous protein; p = 0.038, <0.001, and <0.001, respectively), inflammation (activation of nuclear factor-kB, hypoxia-inducible factor-1α, macrophages, and NLR family pyrin domain containing 3; upregulation of tumor necrosis factor-α, interleukin-1β, and interleukin-6; p = 0.03, <0.001, <0.001, <0.001, <0.001, <0.001, and <0.001, respectively), lipid peroxidation (p < 0.001), and apoptosis (DNA fragmentation, p = 0.003) in lung tissues, as well as lower lung injury level (decreases in tidal volume, peak inspiratory flow, and end expiratory volume; increases in resistance, injury score, and tissue water content; p < 0.001, <0.001, <0.001, <0.001, <0.001, and =0.002, respectively) in the DIOLPSExo group than in the DIOLPS group. In conclusion, exosomes from human pcMSCs mitigate pulmonary ER stress, inflammation, oxidation, apoptosis, and lung injury in lipopolysaccharide-treated obese mice.

Retrospective evaluation of the use of quick Sepsis-related Organ Failure Assessment (qSOFA) as predictor of mortality and length of hospitalization in dogs with pyometra (2013-2019): 52 cases

OBJECTIVE

To evaluate the prognostic utility of quick Sepsis-related Organ Failure Assessment (qSOFA) for prediction of in-hospital mortality and length of hospitalization in dogs with pyometra.

DESIGN

Retrospective cohort study from February 2013 to April 2019 SETTING: Tertiary referral hospital ANIMALS: Fifty-two dogs referred with confirmed diagnosis of pyometra INTERVENTIONS: None MEASUREMENTS AND PRINCIPAL OUTCOMES: Sixty-five percent of dogs survived to discharge. A cut-off score of ≥2 for qSOFA was associated with in-hospital mortality (odds ratio 6.51 [95% CI: 1.35 - 31.3]) P = 0.019. The area under the receiver operator characteristic curve for a qSOFA score ≥ 2 for mortality was 0.72 (95% CI: 0.59-0.85), with a sensitivity of 77.8% and a specificity of 66.7%. The mean ± SD number of organs with dysfunction was significantly higher in dogs with a qSOFA score ≥2 1.76 ± 0.83 compared to dogs with a qSOFA score < 2 1.08 ± 1.09, P = 0.015. The presence of a qSOFA score ≥ 2 was associated with a longer time of hospitalization in survivors with a median (interquartile range) length of stay in qSOFA < 2 (48 [33]) hours versus qSOFA score ≥ 2 (78 [52]) hours, P = 0.027.

CONCLUSIONS

In dogs with pyometra, the qSOFA score was associated with mortality and length of hospitalization. This score might be useful to improve the risk stratification in dogs with pyometra. Further studies are necessary to evaluate the predictive capacity of qSOFA in other septic patient populations.

Kinetics of Immunoglobulins in Septic Shock Patients Treated With an IgM- and IgA-Enriched Intravenous Preparation: An Observational Study

Objective: To assess the variations of the blood levels of immunoglobulins (Ig) in septic shock patients treated with an Ig preparation enriched in IgM and IgA (eIg).

Design: The blood levels of Ig in survivors (S) and non-survivors (NS) of a group of septic shock patients were measured before the initial administration (D0) and 1 (D1), 4 (D4), and 7 (D7) days thereafter. The SAPS II score, the capillary permeability, the primary site of infection, the antibiotic appropriateness, and the outcome at 28 days were also assessed.

Results: In the interval D0–D7, the IgM increased significantly only in the S while remained stable in NS; the IgA significantly increased in both groups; the IgG did not vary significantly in both groups. At D4, the capillary permeability significantly decreased in S but not in NS.

Conclusions: The kinetics of the different classes of Ig after eIg were different between S and NS. This could be related either to (a) different capillary permeability in the two groups or to (b) higher Ig consumption in NS. Further studies to confirm the benefits of eIg in the treatment of sepsis syndrome and to define the specific target population and the correct eIg dose are warranted.

Registry on extracorporeal multiple organ support with the advanced organ support (ADVOS) system: 2-year interim analysis

The objective of this registry is to collect data on real-life treatment conditions for patients for whom multiple organ dialysis with Advanced Organ Support (ADVOS) albumin hemodialysis is indicated.This registry was performed under routine conditions and without any study-specific intervention, diagnostic procedures, or assessments. Data on clinical laboratory tests, health status, liver function, vital signs, and examinations were collected (DRKS-ID: DRKS00017068). Mortality rates 28 and 90 days after the first ADVOS treatment, adverse events and ADVOS treatment parameters, including treatment abortions, were documented.This analysis was performed 2 years after the first patient was included on January 18, 2017. As of February 20, 2019, 4 clinical sites in Germany participated and enrolled 118 patients with a median age of 60 (IQR: 45, 69) of whom 70 were male (59.3%). Patients had a median SOFA Score of 14 (IQR: 11, 16) and a predicted mortality of 80%. The median number of failing organs was 3 (IQR: 2, 4).Four hundred twenty nine ADVOS treatments sessions were performed with a median duration of 17 hours (IQR: 6, 23). A 5.8% of the ADVOS sessions (25 of 429) were aborted due to device related errors, while 14.5% (62 of 429) were stopped for other reasons. Seventy nine adverse events were documented, 13 of them device related (all clotting, and all recovered without sequels).A significant reduction in serum creatinine (1.5 vs 1.2 mg/dl), blood urea nitrogen (24 vs 17 mg/dl) and bilirubin (6.9 vs 6.5 mg/dl) was observed following the first ADVOS treatment session. Blood pH, bicarbonate (HCO3-) and base excess returned to the physiological range, while partial pressure of carbon dioxide (pCO2) remained unchanged. At the time of the analysis, 28- and 90-day mortality were 60% and 65%, respectively, compared to an expected ICU-mortality rate of 80%. SOFA score was an independent predictor for outcome in a multivariable logistic regression analysis.The reported data show a high quality and completion of all participating centers. Data interpretation must be cautious due to the small number of patients, and the nature of the registry, without a control group. However, the data presented here show an improvement of expected mortality rates. Minor clotting events similar to other dialysis therapies occurred during the treatments.

Therapeutic approaches targeting renin-angiotensin system in sepsis and its complications

Sepsis, caused by the inappropriate host response to infection, is characterized by excessive inflammatory response and organ dysfunction, thus becomes a critical clinical problem. Commonly, sepsis may progress to septic shock and severe complications, including acute kidney injury (AKI), acute respiratory distress syndrome (ARDS), sepsis-induced myocardial dysfunction (SIMD), liver dysfunction, cerebral dysfunction, and skeletal muscle atrophy, which predominantly contribute to high mortality. Additionally, the global pandemic of coronavirus disease 2019 (COVID-19) raised the concern of development of effectve therapeutic strategies for viral sepsis. Renin-angiotensin system (RAS) may represent as a potent therapeutic target for sepsis therapy. The emerging role of RAS in the pathogenesis of sepsis has been investigated and several preclinical and clinical trials targeting RAS for sepsis treatment revealed promising outcomes. Herein, we attempt to review the effects and mechanisms of RAS manipulation on sepsis and its complications and provide new insights into optimizing RAS interventions for sepsis treatment.

Exosomes in Sepsis

Sepsis is a severe state of infection with high mortality. Pathogen-associated molecular patterns and damage-associated molecular patterns (DAMPs) initiate dysregulated systemic inflammation upon binding to pattern recognition receptors. Exosomes are endosome-derived vesicles, which carry proteins, lipids and nucleic acids, and facilitate intercellular communications. Studies have shown altered contents and function of exosomes during sepsis. In sepsis, exosomes carry increased levels of cytokines and DAMPs to induce inflammation. Exosomal DAMPs include, but are not limited to, high mobility group box 1, heat shock proteins, histones, adenosine triphosphate, and extracellular RNA. Exosomes released during sepsis have impact on multiple organs, including the lungs, kidneys, liver, cardiovascular system, and central nervous system. Here, we review the mechanisms of inflammation caused by exosomes, and their contribution to multiple organ dysfunction in sepsis.

Advanced organ support (ADVOS) in the critically ill: first clinical experience in patients with multiple organ failure

Background

Prevalence of multiple organ failure (MOF) in critically ill patients is increasing and associated mortality remains high. Extracorporeal organ support is a cornerstone in the management of MOF. We report data of an advanced hemodialysis system based on albumin dialysis (ADVOS multi device) that can regulate acid–base balance in addition to the established properties of renal replacement therapy and albumin dialysis systems in critically ill patients with MOF.

Methods

34 critically ill patients with MOF received 102 ADVOS treatment sessions in the Department of Intensive Care Medicine of the University Medical Center Hamburg-Eppendorf. Markers of metabolic detoxification and acid–base regulation were collected and blood gas analyses were performed. A subgroup analyses were performed in patients with severe acidemia (pH < 7.2).

Results

Median number of treatment sessions was 2 (range 1–9) per patient. Median duration of treatment was 17.5 (IQR 11–23) hours per session. Treatment with the ADVOS multi-albumin dialysis device caused a significant decrease in bilirubin levels, serum creatinine, BUN and ammonia levels. The relative elimination rate of bilirubin was concentration dependent. Furthermore, a significant improvement in blood pH, HCO₃⁻ and PaCO₂, was achieved during ADVOS treatment including six patients that suffered from severe metabolic acidosis refractory to continuous renal replacement therapy. Delta pH, HCO₃⁻ and PaCO₂ were significantly affected by the ADVOS blood flow rate and pH settings. This improvement in the clinical course during ADVOS treatments allowed a reduction in norepinephrine during ADVOS therapy. Treatments were well tolerated. Mortality rates were 50% and 62% for 28 and 90 days, respectively.

Conclusions

In this case series in patients with MOF, ADVOS was able to eliminate water-soluble and albumin-bound substances. Furthermore, the device corrected severe metabolic and respiratory acid–base disequilibrium. No major adverse events associated with the ADVOS treatments were observed.

NLRP3 inflammasome inhibition attenuates sepsis-induced platelet activation and prevents multi-organ injury in cecal-ligation puncture

Sepsis is characterized by organ dysfunction due to a dysregulated immune response to infection. Currently, no effective treatment for sepsis exists. Platelets are recognized as mediators of the immune response and may be a potential therapeutic target for the treatment of sepsis. We previously demonstrated that NLRP3 inflammasome activation in sepsis-induced activated platelets was associated with multi-organ injury in the cecal-ligation puncture (CLP) rat model of sepsis. In this study, we tested the hypothesis that inhibition of NLRP3 would inhibit platelet activation and attenuate multi-organ injury in the CLP rat. CLP (n = 10) or Sham (n = 10) surgery were performed in male and female Sprague-Dawley rats. A subset of CLP rats were treated with MCC950 (50mg/kg/d), a specific NLRP3 inhibitor (CLP+MCC950, n = 10). At 72 hrs. post-CLP, blood and organs were harvested for analysis of platelet activation, NLRP3 activation, inflammation and end organ damage. Platelet activation increased from 8±0.8% in Sham to 16±1% in CLP, and was reduced to 9±1% in CLP+M rats (p<0.05). NLRP3 activation was also increased in platelets of CLP vs Sham. NLRP3 expression was unchanged in kidney and lung after CLP, but Caspase 1 expression and IL-1β were increased. MCC950 treatment attenuated NLRP3 activation in platelets. Plasma, kidney, and lung levels of NLRP3 inflammasome associated cytokines, IL-1ß and IL-18, were significantly increased in CLP compared to Sham rats. Inhibition of NLRP3 normalized cytokine levels. Glomerular injury, pulmonary edema, and endothelial dysfunction markers were increased in CLP rats vs Sham. MCC950 treatment significantly decreased renal and pulmonary injury and endothelial dysfunction in CLP+M. Our results demonstrate a role for NLRP3 in contributing to platelet activation and multi-organ injury in sepsis.

The Conundrum of Septic Shock Imitators in Patients with Hematologic Cancers: Case Presentation and Possible Differential Diagnoses

The authors describe the case of a patient treated with several cycles of chemotherapy due to an advanced stage non-Hodgkin lymphoma. One daafter the last cycle, he was admitted to our Intensive Care Unit with a septic shock-like clinical picture which didn't respond to the aggressive treatment and the patient died a few hours later. The autoptical findings cast some doubts on the diagnosis, and demonstrated the presence of other factors imitating its symptoms. In this article, the mimickers of septic shock are reviewed and discussed, as some of them require an aggressive immunosuppression instead of the recommended treatment for septic shock.

Persistent Mitochondrial Dysfunction Linked to Prolonged Organ Dysfunction in Pediatric Sepsis

OBJECTIVES

Limited data exist about the timing and significance of mitochondrial alterations in children with sepsis. We therefore sought to determine if alterations in mitochondrial respiration and content within circulating peripheral blood mononuclear cells were associated with organ dysfunction in pediatric sepsis.

DESIGN

Prospective observational study SETTING:: Single academic PICU.

PATIENTS

One-hundred sixty-seven children with sepsis/septic shock and 19 PICU controls without sepsis, infection, or organ dysfunction.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Mitochondrial respiration and content were measured in peripheral blood mononuclear cells on days 1-2, 3-5, and 8-14 after sepsis recognition or once for controls. Severity and duration of organ dysfunction were determined using the Pediatric Logistic Organ Dysfunction score and organ failure-free days through day 28. Day 1-2 maximal uncoupled respiration (9.7 ± 7.7 vs 13.7 ± 4.1 pmol O2/s/10 cells; p = 0.02) and spare respiratory capacity (an index of bioenergetic reserve: 6.2 ± 4.3 vs 9.6 ± 3.1; p = 0.005) were lower in sepsis than controls. Mitochondrial content, measured by mitochondrial DNA/nuclear DNA, was higher in sepsis on day 1-2 than controls (p = 0.04) and increased in sepsis patients who had improving spare respiratory capacity over time (p = 0.005). Mitochondrial respiration and content were not associated with day 1-2 Pediatric Logistic Organ Dysfunction score, but low spare respiratory capacity was associated with higher Pediatric Logistic Organ Dysfunction score on day 3-5. Persistently low spare respiratory capacity was predictive of residual organ dysfunction on day 14 (area under the receiver operating characteristic, 0.72; 95% CI, 0.61-0.84) and trended toward fewer organ failure-free days although day 28 (β coefficient, -0.64; 95% CI, -1.35 to 0.06; p = 0.08).

CONCLUSIONS

Mitochondrial respiration was acutely decreased in peripheral blood mononuclear cells in pediatric sepsis despite an increase in mitochondrial content. Over time, a rise in mitochondrial DNA tracked with improved respiration. Although initial mitochondrial alterations in peripheral blood mononuclear cells were unrelated to organ dysfunction, persistently low respiration was associated with slower recovery from organ dysfunction.

Association Between Gut Bacterial Diversity and Mortality in Septic Shock Patients: A Cohort Study

Background

Gut bacterial diversity is decreased in a proportion of patients with septic shock. We attempted to validate the hypothesis that low bacterial diversity increases the risk of mortality.

Material/Methods

All patients with septic shock seen at 2 medical center from 2016 through 2019 were included in this cohort study. Total DNA was isolated from stool, and high-throughput sequencing was performed. Clinical data were extracted from patient medical records and hospital databases. Patients were grouped by gut microbiota bacterial diversity (measured by Shannon diversity index) on presentation. We used logistic regression analysis to evaluate the risk of 28-day mortality in septic patients with low Shannon diversity index.

Results

Of the 150 patients enrolled in this study, low bacterial diversity (Shannon index <3.0) was found in 80 patients and normal diversity (Shannon index ≥3.0) was found in 70 patients. Low diversity was associated with a higher unadjusted mortality risk, compared to those with normal diversity (odds ratio [OR] 2.04, 95% confidence interval [CI] 1.35–2.83). However, this result became non-significant after adjusting the confounding factors such as age, sex, severity of disease, comorbid status, usage of probiotics, enteral nutrition, and antimicrobial drugs (OR 1.93, 95% CI 0.55–2.69).

Conclusions

Our study does not support that low gut bacterial diversity is an independent risk factor for mortality in intensive care unit patients with septic shock.

Transient receptor potential melastatin 2-mediated heme oxygenase-1 has a role for bacterial clearance by regulating autophagy in peritoneal macrophages during polymicrobial sepsis

Our previous study indicated an important protective role of transient receptor potential melastatin 2 (TRPM2) in controlling bacterial clearance in macrophages during polymicrobial sepsis by regulating heme oxygenase-1. Autophagy is necessary for macrophages to kill invasive bacteria. In the present study, TRPM2 knockout (KO) mice show decreased heme oxygenase-1 and autophagy in peritoneal macrophages after caecal ligation and puncture surgery. Caecal ligation and puncture-induced autophagy in peritoneal macrophages is dependent on heme oxygenase-1. TRPM2 KO mice treated with heme oxygenase-1 inducer before caecal ligation and puncture significantly increase autophagy of peritoneal macrophages, bacterial clearance rate and survival rate. In addition, TRPM2 KO mice treated with heme oxygenase-1 inducer before caecal ligation and puncture significantly attenuate organ injury and systemic inflammation. These improvements are reversed by autophagy inhibitor. Therefore, our findings suggest that TRPM2-mediated heme oxygenase-1 has a role for bacterial clearance possibly by regulating autophagy in peritoneal macrophages during polymicrobial sepsis.

Prognostic Value of Secretoneurin in Patients With Severe Sepsis and Septic Shock: Data From the Albumin Italian Outcome Sepsis Study

OBJECTIVES

Secretoneurin directly influences cardiomyocyte calcium handling, and circulating secretoneurin levels seem to improve risk prediction in patients with myocardial dysfunction by integrating information on systemic stress, myocardial function, and renal function. Accordingly, in this study, we hypothesized that secretoneurin would improve risk prediction in patients with sepsis and especially in patients with septic shock as these patients are more hemodynamically unstable.

DESIGN

Multicenter, interventional randomized clinical trial.

SETTING

Multicenter, pragmatic, open-label, randomized, prospective clinical trial testing fluid administration with either 20% human albumin and crystalloids or crystalloid solutions alone in patients with severe sepsis or septic shock (The Albumin Italian Outcome Sepsis).

PATIENTS OR SUBJECTS

In total, 540 patients with septic shock and 418 patients with severe sepsis.

INTERVENTIONS

Either 20% human albumin and crystalloids or crystalloid solutions alone.

MEASUREMENTS AND MAIN RESULTS

We measured secretoneurin on days 1, 2, and 7 after randomization and compared the prognostic value of secretoneurin for ICU and 90-day mortality with established risk indices and cardiac biomarkers in septic shock and severe sepsis. High secretoneurin levels on day 1 were associated with age and serum concentrations of lactate, bilirubin, creatinine, and N-terminal pro-B-type natriuretic peptide. Adjusting for established risk factors and cardiovascular biomarkers, secretoneurin levels on day 1 were associated with ICU (odds ratio, 2.27 [95% CI, 1.05-4.93]; p = 0.04) and 90-day mortality (2.04 [1.02-4.10]; p = 0.04) in patients with septic shock, but not severe sepsis without shock. Secretoneurin levels on day 2 were also associated with ICU (3.11 [1.34-7.20]; p = 0.008) and 90-day mortality (2.69 [1.26-5.78]; p = 0.01) in multivariate regression analyses and improved reclassification in patients with septic shock, as assessed by the net reclassification index. Randomized albumin administration did not influence the associations between secretoneurin and outcomes.

CONCLUSIONS

Secretoneurin provides early and potent prognostic information in septic patients with cardiovascular instability.

Serum developmental endothelial locus-1 is associated with severity of sepsis in animals and humans

Disruption of the endothelial glycocalyx has a prominent role in the pathophysiology of sepsis. Developmental endothelial locus-1 (Del-1) is an endothelial-derived anti-inflammatory factor. We hypothesized that degradation of the endothelial glycocalyx during sepsis may increase serum Del-1. A mouse model of sepsis was created using cecal ligation and puncture. In septic mice, the endothelial glycocalyx was nearly completely degraded, with less formation of Del-1 in the endothelium and extracellular matrix than in control mice. Serum Del-1 levels were significantly increased in the septic mice with increasing severity of sepsis. Serum Del-1 levels were also measured in 84 patients with sepsis and septic shock and in 20 control subjects. The median serum Del-1 level in patients with sepsis was significantly higher than that in healthy controls. The high Del-1 group had higher illness severity scores and contained more patients with organ dysfunction than the low Del-1 group. The 90-day mortality rate was significantly higher in the high Del-1 group than in the low Del-1 group. Multivariate analysis indicated a tendency for a high serum Del-1 level to be associated with a higher mortality risk. Increased serum Del-1 may be a novel diagnostic biomarker of sepsis and an indicator of disease severity.

Clinical Trajectories and Causes of Death in Septic Patients with a Low APACHE II Score

Clinical course and mortality in septic patients with low disease severity remain poorly understood and is worth further investigation. We enrolled septic patients admitted to intensive care units (ICUs) between 2010 and 2014 with Acute Physiology and Chronic Health Evaluation II (APACHE II) scores of ≤15. We sought to determine their clinical trajectories and causes of death, and to analyze risk factors associated with in-hospital mortality. A total of 352 patients were included, of whom 89 (25%) did not survive to hospital discharge, at a rate higher than predicted (<21%) by the APACHE II score. Approximately one third (31/89) of non-survivors succumbed to index sepsis; however, more patients (34/89) died of subsequent sepsis. New-onset ICU sepsis developed in 99 (28%) patients and was an independent risk factor for mortality. In addition, septic patients with comorbid malignancy or index infection acquired in the hospital settings were more likely to have in-hospital mortality than those without. In conclusion, septic patients with low APACHE II scores were at a higher mortality risk than expected, and subsequent sepsis rather than index sepsis was the primary cause of death. This study provides insight into unexpected clinical trajectories and outcomes of septic patients with low disease severity at ICU admission and highlights the need for more research and clinical attention in this patient population.

Increased Expression of lncRNA UCA1 and HULC Is Required for Pro-inflammatory Response During LPS Induced Sepsis in Endothelial Cells

Systemic uncontrolled inflammatory response, also termed as sepsis, is responsible for many mortalities. Bacterial endotoxin, lipopolysaccharide (LPS), is a major cause of sepsis in endothelial cells. Even though a lot of research has been done to define underlying mechanisms of LPS induced sepsis, the role of long non-coding RNAs (lncRNAs), a group of >200 kb RNAs in sepsis is not well-defined. Expression of pro-inflammatory mediators IL6, ICAM1, and VCAM1 (which encodes interleukin-6, intercellular adhesion molecule-1, and vascular cell adhesion molecule-1, respectively) were determined following LPS treatment of human dermal microvascular endothelial cells (HMECs) for 24 h to confirm sepsis induction. RNA immunoprecipitation (RIP) analysis was performed using the chromatin modifying proteins (CMPs), heterogeneous nuclear ribonucleoprotein (hnRNP) K and corepressors of the RE-1 silencing transcription factor (coREST) as individual baits. Quantitative real time polymerase chain reaction (qRT-PCR) was performed on RNA isolated from immunoprecipitated pellets for six different lncRNAs. The effect of the differentially expressed lncRNAs were determined by ectopic overexpression of the lncRNAs before induction of sepsis. Expression of IL6, ICAM1, and VCAM1 were significantly upregulated following treatment of the HMECs with LPS for 24 h confirming induction of sepsis. RIP and qRT-PCR analysis revealed that the lncRNAs HULC, UCA1, and MALAT-1 were significantly enriched with the CMPs after sepsis. RNA interference using siRNAs targeting HULC and UCA1, but not MALAT-1, decreased the expression of IL6, ICAM1, and VCAM1 to endogenous levels. Our results were further validated in an in vivo model of sub-lethal LPS-induced sepsis, whereby siRNA mediated knockdown of UCA1 and HULC lncRNAs prevented induction of VCAM1, ICAM1, and IL6, as assayed by immunohistochemistry. Cumulatively, these results suggest that LPS induced in vitro sepsis in endothelial cells and induction of pre-inflammatory mediators are at least in part due to increased expression of the UCA1 and HULC lncRNAs.

NLRP3 inflammasome activation in platelets in response to sepsis

Sepsis is a complex syndrome characterized by organ dysfunction and a dysregulated immune host response to infection. There is currently no effective treatment for sepsis, but platelets have been proposed as a potential therapeutic target for the treatment of sepsis. We hypothesized that the NLRP3 inflammasome is activated in platelets during sepsis and may be associated with multiorgan injury in response to polymicrobial sepsis. Polymicrobial sepsis was induced by cecal ligation and puncture (CLP) in 12- to 13-week-old male Sprague-Dawley rats. The necrotic cecum was removed at 24 h post-CLP. At 72 h post-CLP, activated platelets were significantly increased in CLP versus Sham rats. Colocalization of NLRP3 inflammasome components was observed in platelets from CLP rats at 72 h post-CLP. Plasma, pulmonary, and renal levels of IL-1β and IL-18 were significantly higher in CLP rats compared to Sham controls. Soluble markers of endothelial permeability were increased in CLP versus Sham. Renal and pulmonary histopathology were markedly elevated in CLP rats compared to Sham controls. NLRP3 is activated in platelets in response to CLP and is associated with inflammation, endothelial permeability and multiorgan injury. Our results indicate that activated platelets may play a role to cause multiorgan injury in sepsis and may have therapeutic potential for the treatment of sepsis multiorgan injury.

Quantification of adherens junction disruption and contiguous paracellular protein leak in human lung endothelial cells under septic conditions

OBJECTIVE

Sepsis is associated with dysfunction of MVEC resulting in organ edema and inflammation. VE-cadherin, a component of MVEC adherens junctions, may be disrupted in sepsis. However, the direct connection between individual MVEC VE-cadherin disruption and increased paracellular permeability is uncertain.

METHODS

Human pulmonary MVEC were cultured on a biotin matrix and treated with cytomix, as a model of sepsis, vs PBS. MVEC permeability was assessed by trans-MVEC monolayer leak of Oregon green 488-conjugated avidin, which bound subcellular biotin to localize sites of paracellular leak. Leak was correlated with individual cell-specific MVEC surface VE-cadherin continuity by fluorescence microscopy.

RESULTS

Cytomix treatment reduced total MVEC VE-cadherin density, disrupted surface VE-cadherin continuity, was associated with intercellular gap formation, and enhanced paracellular avidin leak. Cytomix-induced MVEC paracellular avidin leak was strongly correlated temporally and was highly contiguous with focal MVEC surface VE-cadherin disruption. Total cellular VE-cadherin density was less strongly correlated with MVEC paracellular avidin leak and individual cell-specific focal surface VE-cadherin discontinuity.

CONCLUSIONS

These data support a mechanistic link between septic human lung MVEC VE-cadherin disruption and contiguous paracellular protein leak, and will permit more detailed assessment of individual cell-specific mechanisms of septic MVEC barrier dysfunction.

Two-way Interaction Effects of Perioperative Complications on 30-Day Mortality in General Surgery

BACKGROUND

Multiple perioperative complications increase mortality risk, and certain complications synergistically increase this risk to a greater degree than might be expected if the complications were independent, but these effects are not well established.

METHODS

This is a retrospective cohort study of 422,827 intraabdominal general surgery patients (American College of Surgeons National Surgical Quality Improvement Program 2005-2011). Eight complications were evaluated: acute respiratory failure (ARF), acute kidney injury (AKI), sepsis/septic shock, stroke, cardiac arrest (CA), myocardial infarction (MI), deep vein thrombosis/pulmonary embolus, and transfusion. Each combination of two complications (28 total) was modeled using a Cox model for 30-day mortality, with adjustment for preoperative comorbidities and risk factors. Additive interaction was determined with the relative excess risk due to interaction (RERI). A positive RERI indicates that the mortality risk with both complications is greater than the sum of the individual mortality risks. Bonferroni correction was applied (α = 0.05/28 = 0.0018).

RESULTS

Seven combinations demonstrated positive interaction: sepsis-CA (RERI 88.1; p < 0.0001), ARF-AKI (RERI 50.5; p < 0.0001), AKI-sepsis (RERI 33.9; p < 0.0001), sepsis-stroke (RERI 33.9; p < 0.0001), ARF-stroke (RERI 32.3; p < 0.0001), AKI-MI (RERI 24.5; p = 0.0013), and ARF-sepsis (RERI 19.2; p < 0.0001). Two combinations demonstrated negative interaction: ARF-CA (RERI -65.1; p = 0.0017) and CA-transfusion (RERI -52.0, p < 0.0001).

CONCLUSIONS

Interaction effects exist between certain complications to increase the risk of short-term mortality. ARF, AKI, sepsis, and stroke were most likely to be involved in positive interactions. Further research into the mechanisms for these effects will be necessary to develop strategies to minimize the compounding effects of multiple complications in the perioperative period.

Esmolol infusion in patients with septic shock and tachycardia: a prospective, single-arm, feasibility study

Background

High adrenergic tone appears to be associated with mortality in septic shock, while adrenergic antagonism may improve survival. In preparation for a randomized trial, we conducted a prospective, single-arm pilot study of esmolol infusion for patients with septic shock and tachycardia that persists after adequate volume expansion.

Methods

From April 2016 to March 2017, we enrolled patients admitted to an intensive care unit with sepsis who were receiving vasopressor infusion and were tachycardic despite adequate volume expansion. All patients received a continuous intravenous infusion of esmolol, targeted to heart rate 80–90/min, while receiving vasopressors. The feasibility outcomes were proportion of eligible patients consented, compliance with pre-infusion safety check, and compliance with the titration protocol. The primary clinical outcome was organ-failure-free days (OFFD) at 28 days.

Results

We enrolled 7 of 10 eligible patients. Mean age was 46 (± 19) years, and mean admission APACHE II was 28 (± 8). Median norepinephrine infusion rate at the initiation of esmolol infusion was 0.20 (0.14–0.23) μg/kg/min. Compliance with the safety check was 100%; compliance with components of the titration protocol was 98–100%. OFFD were 26 (24.5–26); all patients survived to day 90. Median peak esmolol infusion was 50 (25–50) μg/kg/min. Median peak norepinephrine infusion rate during esmolol infusion was 0.46 (0.13–0.50) μg/kg/min. Four patients achieved target heart rate. Protocol-defined stop events, suggesting possible intolerance to a given infusion rate, occurred in three patients, all of whom were receiving at least 50 μg/kg/min of esmolol.

Conclusions

In a pilot, single-arm study, we report the first published experience with esmolol infusion in tachycardic patients with septic shock in the United States. These findings support a phase 2 trial of esmolol infusion for septic shock. Lower infusion rates of esmolol infusion may be better tolerated and more feasible than higher infusion rates for such a trial.

Trial registration

This study was retrospectively registered at ClinicalTrials.gov (NCT02841241) on 19 July 2016.

Electronic supplementary material

The online version of this article (10.1186/s40814-018-0321-5) contains supplementary material, which is available to authorized users.

Patterns of Death in Patients with Sepsis and the Use of Hydrocortisone, Ascorbic Acid, and Thiamine to Prevent These Deaths

Background: In general, patients with sepsis die from the host response to the infecting pathogen rather than from the infecting pathogen itself. Four patterns of death have been identified in sepsis, namely vasoplegic shock, single-organ respiratory failure (acute respiratory distress syndrome [ARDS]), multi-system organ failure (MSOF), and persistent MSOF with ongoing inflammation and immunosuppression with recurrent infections (persistent inflammation-immunosuppression and catabolism syndrome [PICS]). To improve the outcome of sepsis adjunctive therapies that modulate the immune system have been tested; these therapies that have targeted specific molecules or pathways have universally failed. Conclusion: We propose that the combination of hydrocortisone, intravenous ascorbic acid, and thiamine (HAT therapy), which synergistically targets multiple pathways, restores the dysregulated immune system and organ injury, and reduces the risk of death and organ failure following sepsis.

Predictors of Early Onset Multiple Organ Dysfunction in Major Burn Patients with Ventilator Support: Experience from A Mass Casualty Explosion

Organ dysfunction is common in patients with major burns and associated with poor outcomes. The risk factors for early onset multiple organ dysfunction syndrome (MODS) in major burn patients with invasive ventilator support has rarely been evaluated before. In this study, major burn patients with invasive ventilator support from 499 victims suffered in a mass casualty color dust explosion were retrospectively enrolled. The development of early MODS that occurred within 5 days after burn injury was determined and the risk factors associated with early MODS were analyzed. A total of 88 patients from five medical centers were included. Their mean total body surface area (TBSA) was 60.9 ± 15.8%, and 45 (51.1%) patients had early MODS. Hematologic failure was the most common organ failure (68.6%), followed by respiratory failure (48.9%). Independent clinical factors associated with early MODS included TBSA ≥55% (OR: 3.83; 95% CI: 1.29-11.37) and serum albumin level <2.1 g/dL upon admission (OR: 3.43; 95% CI: 1.01-11.57). Patients with early MODS had prolonged ventilator dependence and longer ICU admission than those without early MODS. Our results showed that early MODS in major burn patients with invasive ventilator support is very common and can be predicted early on admission.

Emerging Adjunctive Approach for the Treatment of Sepsis: Vitamin C and Thiamine

Evidence is emerging that parenteral administration of high-dose vitamin C and thiamine may be a beneficial adjuvant therapy of severe sepsis and septic shock. Despite modern practices in critical care medicine, sepsis and severe sepsis remain a leading cause of morbidity and mortality in the critical care unit.

Autophagy and mitochondrial biogenesis impairment contribute to age-dependent liver injury in experimental sepsis: dysregulation of AMP-activated protein kinase pathway

Age is an independent risk factor of multiple organ failure in patients with sepsis. However, the age-related mechanisms of injury are not known. AMPK is a crucial regulator of energy homeostasis, which controls mitochondrial biogenesis by activation of peroxisome proliferator-activated receptor-γ coactivator-α (PGC-1α) and disposal of defective organelles by autophagy. We investigated whether AMPK dysregulation might contribute to age-dependent liver injury in young (2-3 mo) and mature male mice (11-13 mo) subjected to sepsis. Liver damage was higher in mature mice than in young mice and was associated with impairment of hepatocyte mitochondrial function, structure, and biogenesis and reduced autophagy. At molecular analysis, there was a time-dependent nuclear translocation of the active phosphorylated catalytic subunits AMPKα1/α2 and PGC-1α in young, but not in mature, mice after sepsis. Treatment with the AMPK activator 5-amino-4-imidazolecarboxamide riboside-1-β-d-ribofuranoside (AICAR) improved liver mitochondrial structure in both age groups compared with vehicle. In loss-of-function studies, young knockout mice with systemic deficiency of AMPKα1 exhibited greater liver injury than did wild-type mice after sepsis. Our study suggests that AMPK is important for liver metabolic recovery during sepsis. Although its function may diminish with age, pharmacological activation of AMPK may be of therapeutic benefit.-Inata, Y., Kikuchi, S., Samraj, R. S., Hake, P. W., O'Connor, M., Ledford, J. R., O'Connor, J., Lahni, P., Wolfe, V., Piraino, G., Zingarelli, B. Autophagy and mitochondrial biogenesis impairment contribute to age-dependent liver injury in experimental sepsis: dysregulation of AMP-activated protein kinase pathway.

Expression Profiling of Long Noncoding RNA Splice Variants in Human Microvascular Endothelial Cells: Lipopolysaccharide Effects In Vitro

Endothelial cell interactions with lipopolysaccharide (LPS) involve both activating and repressing signals resulting in pronounced alterations in their transcriptome and proteome. Noncoding RNAs are now appreciated as posttranscriptional and translational regulators of cellular signaling and responses, but their expression status and roles during endothelial interactions with LPS are not well understood. We report on the expression profile of long noncoding (lnc) RNAs of human microvascular endothelial cells in response to LPS. We have identified a total of 10,781 and 8310 lncRNA transcripts displaying either positive or negative regulation of expression, respectively, at 3 and 24 h posttreatment. A majority of LPS-induced lncRNAs are multiexonic and distributed across the genome as evidenced by their presence on all chromosomes. Present among these are a total of 44 lncRNAs with known regulatory functions, of which 41 multiexonic lncRNAs have multiple splice variants. We have further validated splice variant-specific expression of EGO (NONHSAT087634) and HOTAIRM1 (NONHSAT119666) at 3 h and significant upregulation of lnc-IL7R at 24 h. This study illustrates the genome-wide regulation of endothelial lncRNA splice variants in response to LPS and provides a foundation for further investigations of differentially expressed lncRNA transcripts in endothelial responses to LPS and pathophysiology of sepsis/septic shock.

Vitamin C: The next step in sepsis management?

Sepsis is a life-threatening medical condition, affecting approximately 26 million people worldwide every year. The disease is a continuum, marked by dysregulated inflammation and hemodynamic instability leading to shock, multi-system organ dysfunction, and death. Over the past decades, there has been a focus on the early identification and treatment of sepsis primarily with bundled and goal directed therapy. Despite these advances, morbidity and mortality has remained high, prompting investigation into novel therapies. Vitamin C is a water-soluble vitamin that plays a role in mediating inflammation through antioxidant activities and is also important in the synthesis of cortisol, catecholamines, and vasopressin, which are key mediators in the disease process. Emerging evidence provides cursory data in support of the administration of vitamin C in addition to standard therapy to ameliorate the effects of inflammation and improve hemodynamic stability in patients with sepsis and septic shock; however, further evidence is needed to support this practice. This review discusses the physiologic role of vitamin C as well as the recent literature and evidence for the use of vitamin C in patients presenting with sepsis.

The Epidemiology of Hospital Death Following Pediatric Severe Sepsis: When, Why, and How Children With Sepsis Die

OBJECTIVE

The epidemiology of in-hospital death after pediatric sepsis has not been well characterized. We investigated the timing, cause, mode, and attribution of death in children with severe sepsis, hypothesizing that refractory shock leading to early death is rare in the current era.

DESIGN

Retrospective observational study.

SETTING

Emergency departments and ICUs at two academic children's hospitals.

PATIENTS

Seventy-nine patients less than 18 years old treated for severe sepsis/septic shock in 2012-2013 who died prior to hospital discharge.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Time to death from sepsis recognition, cause and mode of death, and attribution of death to sepsis were determined from medical records. Organ dysfunction was assessed via daily Pediatric Logistic Organ Dysfunction-2 scores for 7 days preceding death with an increase greater than or equal to 5 defined as worsening organ dysfunction. The median time to death was 8 days (interquartile range, 1-12 d) with 25%, 35%, and 49% of cumulative deaths within 1, 3, and 7 days of sepsis recognition, respectively. The most common cause of death was refractory shock (34%), then multiple organ dysfunction syndrome after shock recovery (27%), neurologic injury (19%), single-organ respiratory failure (9%), and nonseptic comorbidity (6%). Early deaths (≤ 3 d) were mostly due to refractory shock in young, previously healthy patients while multiple organ dysfunction syndrome predominated after 3 days. Mode of death was withdrawal in 72%, unsuccessful cardiopulmonary resuscitation in 22%, and irreversible loss of neurologic function in 6%. Ninety percent of deaths were attributable to acute or chronic manifestations of sepsis. Only 23% had a rise in Pediatric Logistic Organ Dysfunction-2 that indicated worsening organ dysfunction.

CONCLUSIONS

Refractory shock remains a common cause of death in pediatric sepsis, especially for early deaths. Later deaths were mostly attributable to multiple organ dysfunction syndrome, neurologic, and respiratory failure after life-sustaining therapies were limited. A pattern of persistent, rather than worsening, organ dysfunction preceded most deaths.

Evaluation of an ADVanced Organ Support (ADVOS) system in a two-hit porcine model of liver failure plus endotoxemia

Background

Novel extracorporeal procedures are constantly being developed and evaluated for use in patients with sepsis. Preclinical evaluation of such procedures usually requires testing in large animal models. In the present work, the safety and efficacy of a recently developed ADVanced Organ Support (ADVOS) system in a newly developed large animal two-hit model of liver failure combined with endotoxemia were tested.

Methods

After establishing the model in more than 50 animals, a randomized study was performed. An inflammatory cholestatic liver injury was initially provoked in pigs. Three days after surgery, endotoxin was gradually administered during 7½ h. Animals were randomized to receive standard medical treatment either with (ADVOS group, n = 5) or without ADVOS (control group, n = 5). The ADVOS treatment was started 2½ h after endotoxemia and continued for 7 h. Survival, cardiovascular, respiratory, renal, liver, coagulation, and cerebral parameters were analyzed.

Results

Three days after surgery, cholestatic injury resulted in hyperbilirubinemia [5.0 mg/dl (IQR 4.3–5.9 mg/dl)], hyperammonemia [292 μg/dl (IQR 291–296 μg/dl)], leukocytosis [20.2 10³/μl (IQR 17.7–21.8 10³/μl)], and hyperfibrinogenemia [713 mg/dl (IQR 654–803 mg/dl)]. After endotoxemia, the ADVOS procedure stabilized cardiovascular, respiratory, and renal parameters and eliminated surrogate markers as bilirubin [2.3 (IQR 2.3–3.0) vs. 5.5 (IQR 4.6–5.6) mg/dl, p = 0.001] and creatinine [1.4 (IQR 1.1–1.7) vs. 2.3 (IQR 2.1–3.1) mg/dl, p = 0.01]. Mortality: All animals in the ADVOS group survived, while all animals in the control group expired during the 10-h observation period (p = 0.002). No adverse events related to the procedure were observed.

Conclusions

The ADVOS procedure showed a promising safety and efficacy profile and improved survival in a sepsis-like animal model with dysfunction of multiple organs. An amelioration of major organ functions (heart and lung) combined with removal of markers for kidney and liver function was observed.

Electronic supplementary material

The online version of this article (doi:10.1186/s40635-017-0144-3) contains supplementary material, which is available to authorized users.

Mitochondria-meditated pathways of organ failure upon inflammation

Liver failure induced by systemic inflammatory response (SIRS) is often associated with mitochondrial dysfunction but the mechanism linking SIRS and mitochondria-mediated liver failure is still a matter of discussion. Current hypotheses suggest that causative events could be a drop in ATP synthesis, opening of mitochondrial permeability transition pore, specific changes in mitochondrial morphology, impaired Ca²⁺ uptake, generation of mitochondrial reactive oxygen species (mtROS), turnover of mitochondria and imbalance in electron supply to the respiratory chain. The aim of this review is to critically analyze existing hypotheses, in order to highlight the most promising research lines helping to prevent liver failure induced by SIRS. Evaluation of the literature shows that there is no consistent support that impaired Ca⁺⁺ metabolism, electron transport chain function and ultrastructure of mitochondria substantially contribute to liver failure. Moreover, our analysis suggests that the drop in ATP levels has protective rather than a deleterious character. Recent data suggest that the most critical mitochondrial event occurring upon SIRS is the release of mtROS in cytoplasm, which can activate two specific intracellular signaling cascades. The first is the mtROS-mediated activation of NADPH-oxidase in liver macrophages and endothelial cells; the second is the acceleration of the expression of inflammatory genes in hepatocytes. The signaling action of mtROS is strictly controlled in mitochondria at three points, (i) at the site of ROS generation at complex I, (ii) the site of mtROS release in cytoplasm via permeability transition pore, and (iii) interaction with specific kinases in cytoplasm. The systems controlling mtROS-signaling include pro- and anti-inflammatory mediators, nitric oxide, Ca²⁺ and NADPH-oxidase. Analysis of the literature suggests that further research should be focused on the impact of mtROS on organ failure induced by inflammation and simultaneously providing a new theoretical basis for a targeted therapy of overwhelmed inflammatory response.

•

Relationship between mitochondrial dysfunction and high lethality upon sepsis.

•

Criteria to define critical for lethality mitochondrial dysfunction.

•

ATP, calcium, mitochondrial ultrastructure and apoptosis, upon inflammation.

•

Regulation of inflammatory processes by mitochondrial ROS.

Differences in Impact of Definitional Elements on Mortality Precludes International Comparisons of Sepsis Epidemiology-A Cohort Study Illustrating the Need for Standardized Reporting

OBJECTIVES

Sepsis generates significant global acute illness burden. The international variations in sepsis epidemiology (illness burden) have implications for region specific health policy. We hypothesised that there have been changes over time in the sepsis definitional elements (infection and organ dysfunction), and these may have impacted on hospital mortality.

DESIGN

Cohort study.

SETTING

We evaluated a high quality, nationally representative, clinical ICU database including data from 181 adult ICUs in England.

PATIENTS

Nine hundred sixty-seven thousand five hundred thirty-two consecutive adult ICU admissions from January 2000 to December 2012.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

To address the proposed hypothesis, we evaluated a high quality, nationally representative, clinical, ICU database of 967,532 consecutive admissions to 181 adult ICUs in England, from January 2000 to December 2012, to identify sepsis cases in a robust and reproducible way. Multinomial logistic regression was used to report unadjusted trends in sepsis definitional elements and in mortality risk categories based on organ dysfunction combinations. We generated logistic regression models and assessed statistical interactions with acute hospital mortality as outcome and cohort characteristics, sepsis definitional elements, and mortality risk categories as covariates. Finally, we calculated postestimation statistics to illustrate the magnitude of clinically meaningful improvements in sepsis outcomes over the study period. Over the study period, there were 248,864 sepsis admissions (25.7%). Sepsis mortality varied by infection sources (19.1% for genitourinary to 43.0% for respiratory; p < 0.001), by number of organ dysfunctions (18.5% for 1 to 69.9% for 5; p < 0.001), and organ dysfunction combinations (18.5% for risk category 1 to 58.0% for risk category 4). The rate of improvement in adjusted hospital mortality was significant (odds ratio, 0.939 [0.934-0.945] per year; p < 0.001), but showed different secular trends in improvement between infection sources.

CONCLUSIONS

Within a sepsis cohort, we illustrate case-mix heterogeneity using definitional elements (infection source and organ dysfunction). In the context of improving outcomes, we illustrate differential secular trends in impact of these variables on adjusted mortality and propose this as a valid reason for international variations in sepsis epidemiology. Our article highlights the need to determine standardized reporting elements for optimal comparisons of international sepsis epidemiology.

Prognostic Value of Secretoneurin in Critically Ill Patients With Infections

OBJECTIVES

Secretoneurin is produced in neuroendocrine cells, and the myocardium and circulating secretoneurin levels provide incremental prognostic information to established risk indices in cardiovascular disease. As myocardial dysfunction contributes to poor outcome in critically ill patients, we wanted to assess the prognostic value of secretoneurin in two cohorts of critically ill patients with infections.

DESIGN

Two prospective, observational studies.

SETTING

Twenty-four and twenty-five ICUs in Finland.

PATIENTS

A total of 232 patients with severe sepsis (cohort #1) and 94 patients with infections and respiratory failure (cohort #2).

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

We measured secretoneurin levels by radioimmunoassay in samples obtained early after ICU admission and compared secretoneurin with other risk indices. In patients with severe sepsis, admission secretoneurin levels (logarithmically transformed) were associated with hospital mortality (odds ratio, 3.17 [95% CI, 1.12-9.00]; p = 0.030) and shock during the hospitalization (odds ratio, 2.17 [1.06-4.46]; p = 0.034) in analyses that adjusted for other risk factors available on ICU admission. Adding secretoneurin levels to age, which was also associated with hospital mortality in the multivariate model, improved the risk prediction as assessed by the category-free net reclassification index: 0.35 (95% CI, 0.06-0.64) (p = 0.02). In contrast, N-terminal pro-B-type natriuretic peptide levels were not associated with mortality in the multivariate model that included secretoneurin measurements, and N-terminal pro-B-type natriuretic peptide did not improve patient classification on top of age. Secretoneurin levels were also associated with hospital mortality after adjusting for other risk factors and improved patient classification in cohort #2. In both cohorts, the optimal cutoff for secretoneurin levels at ICU admission to predict hospital mortality was ≈ 175 pmol/L, and higher levels were associated with mortality also when adjusting for Simplified Acute Physiology Score II and Sequential Organ Failure Assessment scores.

CONCLUSIONS

Secretoneurin levels provide incremental information to established risk indices for the prediction of mortality and shock in critically ill patients with severe infections.

Procalcitonin Impairs Liver Cell Viability and Function In Vitro: A Potential New Mechanism of Liver Dysfunction and Failure during Sepsis?

Purpose. Liver dysfunction and failure are severe complications of sepsis and result in poor outcome and increased mortality. The underlying pathologic mechanisms of hepatocyte dysfunction and necrosis during sepsis are only incompletely understood. Here, we investigated whether procalcitonin, a biomarker of sepsis, modulates liver cell function and viability. Materials and Methods. Employing a previously characterized and patented biosensor system evaluating hepatocyte toxicity in vitro, human hepatocellular carcinoma cells (HepG2/C3A) were exposed to 0.01-50 ng/mL procalcitonin for 2 × 72 h and evaluated for proliferation, necrosis, metabolic activity, cellular integrity, microalbumin synthesis, and detoxification capacity. Acetaminophen served as positive control. For further standardization, procalcitonin effects were confirmed in a cellular toxicology assay panel employing L929 fibroblasts. Data were analyzed using ANOVA/Tukey's test. Results. Already at concentrations as low as 0.25 ng/mL, procalcitonin induced HepG2/C3A necrosis (P < 0.05) and reduced metabolic activity, cellular integrity, synthesis, and detoxification capacity (all P < 0.001). Comparable effects were obtained employing L929 fibroblasts. Conclusion. We provide evidence for procalcitonin to directly impair function and viability of human hepatocytes and exert general cytotoxicity in vitro. Therapeutical targeting of procalcitonin could thus display a novel approach to reduce incidence of liver dysfunction and failure during sepsis and lower morbidity and mortality of septic patients.

New or Progressive Multiple Organ Dysfunction Syndrome in Pediatric Severe Sepsis: A Sepsis Phenotype With Higher Morbidity and Mortality

OBJECTIVES

To describe the epidemiology, morbidity, and mortality of new or progressive multiple organ dysfunction syndrome in children with severe sepsis.

DESIGN

Secondary analysis of a prospective, cross-sectional, point prevalence study.

SETTING

International, multicenter PICUs.

PATIENTS

Pediatric patients with severe sepsis identified on five separate days over a 1-year period.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Of 567 patients from 128 PICUs in 26 countries enrolled, 384 (68%) developed multiple organ dysfunction syndrome within 7 days of severe sepsis recognition. Three hundred twenty-seven had multiple organ dysfunction syndrome on the day of sepsis recognition. Ninety-one of these patients developed progressive multiple organ dysfunction syndrome, whereas an additional 57 patients subsequently developed new multiple organ dysfunction syndrome, yielding a total proportion with severe sepsis-associated new or progressive multiple organ dysfunction syndrome of 26%. Hospital mortality in patients with progressive multiple organ dysfunction syndrome was 51% compared with patients with new multiple organ dysfunction syndrome (28%) and those with single-organ dysfunction without multiple organ dysfunction syndrome (10%) (p < 0.001). Survivors of new or progressive multiple organ dysfunction syndrome also had a higher frequency of moderate to severe disability defined as a Pediatric Overall Performance Category score of greater than or equal to 3 and an increase of greater than or equal to 1 from baseline: 22% versus 29% versus 11% for progressive, new, and no multiple organ dysfunction syndrome, respectively (p < 0.001).

CONCLUSIONS

Development of new or progressive multiple organ dysfunction syndrome is common (26%) in severe sepsis and is associated with a higher risk of morbidity and mortality than severe sepsis without new or progressive multiple organ dysfunction syndrome. Our data support the use of new or progressive multiple organ dysfunction syndrome as an important outcome in trials of pediatric severe sepsis although efforts are needed to validate whether reducing new or progressive multiple organ dysfunction syndrome leads to improvements in more definitive morbidity and mortality endpoints.

Reasons for death in patients with sepsis and septic shock

PURPOSE

Understanding the underlying cause of mortality in sepsis has broad implications for both clinical care and interventional trial design. However, reasons for death in sepsis remain poorly understood. We sought to characterize reasons for in-hospital mortality in a population of patients with sepsis or septic shock.

MATERIALS AND METHODS

We performed a retrospective review of patients admitted to the intensive care unit with sepsis or septic shock who died during their index admission. Reasons for death were classified into 6 categories determined a priori by group consensus. Interrater reliability was calculated and Fleiss κ reported. The associations between selected patient characteristics (eg, serum lactate) and reason for death were also assessed.

RESULTS

One hundred fifteen patients were included. Refractory shock (40%) and comorbid withdrawal of care (44%) were the most common reasons for death. Overall interrater agreement was substantial (κ = 0.61, P<.01). Lactate was higher in patients who died because of refractory shock as compared with those who died for other reasons (4.7 vs 2.8 mmol/L, P<.01).

CONCLUSION

In this retrospective cohort, refractory shock and comorbid withdrawal of care were the most common reasons for death. Following prospective validation, the classification methodology presented here may be useful in the design/interpretation of trials in sepsis.

Enhanced Innate Inflammation Induced by Anti-BTLA Antibody in Dual Insult Model of Hemorrhagic Shock/Sepsis

Sepsis following hemorrhagic shock is a common clinical condition, in which innate immune system suffers from severe suppression. B and T lymphocyte attenuator (BTLA) is an immune-regulatory coinhibitory receptor expressed not only on adaptive, but also on innate immune cells. Our previous data showed that BTLA gene deficient mice were protected from septic mortality when compared with wild-type control C57BL/6 mice. Here, we extended our study by treating C57BL/6 mice with an anti-BTLA monoclonal antibody (clone 6A6; reported to have the ability to neutralize or agonize/potentiate BTLA signaling) in a mouse model of hemorrhagic shock (Hem) followed by sepsis induced by cecal ligation and puncture (CLP); positing initially that if BTLA engagement was neutralized, like gene deficiency, an anti-BTLA mAb would have the similar effects on the inflammatory response/morbidity in these mice after such insults. Here, we report that BTLA expression is elevated on innate immune cells after Hem/CLP. However, anti-BTLA antibody treatment increased cytokine (TNF-α, IL-12, IL-10)/chemokine (KC, MIP-2, MCP-1) levels and inflammatory cells (neutrophils, macrophages, dendritic cells) recruitment in the peritoneal cavity, which in turn aggravated organ injury and elevated these animals' mortality in Hem/CLP. When compared with the protective effects of our previous study using BTLA gene deficient mice in a model of lethal septic challenge, we further confirmed BTLA's contribution to enhanced innate cell recruitment, elevated IL-10 levels, and reduced survival, and that engagement of antibody with BTLA potentiates/exacerbates the pathophysiology in Hem/sepsis.