Pathogenesis and management of multiple organ dysfunction or failure in severe sepsis and septic shock

Elevated plasma D-dimer levels are associated with the poor prognosis of critically ill children

BACKGROUND

D-dimer has been shown as a valuable predictor for the prognosis of sepsis. But the prognostic association of an elevated D-dimer with adverse outcomes of all critical illnesses in pediatric intensive care unit (PICU) has received far less emphasis.

METHODS

This was a single-center retrospective study, including 7,648 critical patients aged between 28 days and 18 years from the pediatric intensive care (PIC) database from 2010 to 2018. The primary outcome was the in-hospital mortality rate.

RESULTS

Higher levels of D-dimer, INR, PT, APTT, and lower Fib were observed in the non-survivor group (all P < 0.001). D-dimer, INR, PT and APTT were independent risk factors for prognosis in critically ill children. There was the highest AUROC in D-dimer for predicting in-hospital mortality of critically ill patients compared with INR, PT, APTT, and Fib (D-dimer: 0.77 vs. INR: 0.73 vs. PT: 0.73 vs. APTT: 0.64 vs. Fib: 0.60). The cut-off value, sensitivity, and specificity of D-dimer were 1.53, 0.65, and 0.77, respectively. Subgroup analysis showed a stable evaluation effectiveness of D-dimer for predicting in-hospital mortality of critically ill patients in the age and gender groups.

CONCLUSIONS

We found poorer coagulation function in the non-survivors compared with the survivors. Among the coagulation indicators, D-dimer was most strongly associated with in-hospital mortality of unselected critically ill children.

Nanobody-loaded immunosorbent for highly-specific removal of interleukin-17A from blood

Elimination of overproduced cytokines from blood can relieve immune system disorders caused by hypercytokinemia. Due to the central roles of interleukin-17A (IL-17A) plays in regulating the immunity and inflammatory responses in humans, here, a novel immunosorbent containing anti-IL-17A nanobodies (Nbs) was constructed for IL-17A removal from blood. The theoretical maximum adsorption capacity estimated from the Langmuir isotherm is up to 11.55 mg/g gel, which is almost consistent with the saturated adsorption capacity determined in dynamic adsorption. The in vitro plasma perfusion test demonstrated a remarkable adsorptive performance of the Nb-coupled sorbent since more than 75% IL-17A could be eliminated under the plasma/sorbent ratio of 1000:1. These results indicated the Nb-loaded immunosorbent can provide a simple and economic platform technology for immunoaffinity depletion of single or even multiple cytokines from plasma.

Effects of CRRT on renal function and toxin clearance in patients with sepsis: a case-control study

OBJECTIVE

To explore the effects of continuous renal replacement therapy (CRRT) on renal function and toxin clearance in patients with sepsis and concurrent acute kidney injury (AKI).

METHOD

A retrospective analysis was performed using the medical records of 115 patients with sepsis and AKI. Among them, 60 patients received routine treatment (group A) and 55 patients received CRRT plus routine treatment (group B).

RESULT

After treatment, the clearance rates of serum creatinine, lactic acid, and urea nitrogen were significantly lower in group A than in group B. The decrease in high-sensitivity C-reactive protein and tumor necrosis factor-α levels after treatment was significantly higher in group B than in group A. For the Acute Physiology Chronic Health Evaluation (APACHE) II and Sequential Organ Failure Assessment (SOFA) scores from the two groups, the scores were significantly lower in group B than in group A. The mortality rate within 28 days was significantly higher in group A than in group B.

CONCLUSION

CRRT can effectively improve the condition of patients with sepsis and AKI, promote elimination of toxins (serum creatinine, lactic acid, and urea nitrogen) from the body, and reduce the mortality rate.

Simultaneous Inhibition of Three Major Cytokines and Its Therapeutic Effects: A Peptide-Based Novel Therapy against Endotoxemia in Mice

Three major cytokines, including tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and IL-6, mediate endotoxemia-induced liver injury. With the similar structures to the binding domains of the three cytokines to their cognate receptors, the novel peptide KCF18 can simultaneously inhibit TNF-α, IL-1β, and IL-6. We elucidated whether KCF18 can alleviate injury of liver in endotoxemic mice. Adult male mice (BALB/cJ) were intraperitoneally (i.p.) administered lipopolysaccharide (LPS, 15 mg/kg; LPS group) or LPS with KCF18 (LKCF group). Mice in the LKCF group received KCF18 (i.p.) at 2 h (0.6 mg/kg), 4 h (0.3 mg/kg), 6 h (0.3 mg/kg), and 8 h (0.3mg/kg) after LPS administration. Mice were sacrificed after receiving LPS for 24 h. Our results indicated that the binding levels of the three cytokines to their cognate receptors in liver tissues in the LKCF group were significantly lower than those in the LPS group (all p < 0.05). The liver injury level, as measured by performing functional and histological analyses and by determining the tissue water content and vascular permeability (all p < 0.05), was significantly lower in the LKCF group than in the LPS group. Similarly, the levels of inflammation (macrophage activation, cytokine upregulation, and leukocyte infiltration), oxidation, necroptosis, pyroptosis, and apoptosis (all p < 0.05) in liver tissues in the LKCF group were significantly lower than those in the LPS group. In conclusion, the KCF18 peptide–based simultaneous inhibition of TNF-α, IL-1β, and IL-6 can alleviate liver injury in mice with endotoxemia.

A new nomogram to predict the need for tracheostomy in burned patients

Purpose

To evaluate the impact of tracheostomy on complications, dysphagia and outcome in second and third degree burned patients.

Methods

Inpatient mortality, dysphagia, severity of burn injury (ABSI, TBSA) and complications in tracheotomized burn patients were compared to (I) non-tracheotomized burn patients and (II) matched tracheotomized non-burn patients.

Results

134 (30.9%) out of 433 patients who underwent tracheostomy, had a significantly higher percentage of inhalation injury (26.1% vs. 7.0%; p < 0.001), higher ABSI (8.9 ± 2.1 vs. 6.0 ± 2.7; p < 0.001) and TBSA score (41.4 ± 19.7% vs. 18.6 ± 18.8%; p < 0.001) compared to 299 non-tracheotomized burn patients. However, complications occurred equally in tracheotomized burn patients and matched controls and tracheostomy was neither linked to dysphagia nor to inpatient mortality at multivariate analysis. In particular, dysphagia occurred in 6.2% of cases and was significantly linked to length of ICU stay (OR 6.2; p = 0.021), preexisting neurocognitive impairments (OR 5.2; p = 0.001) and patients’ age (OR 3.4; p = 0.046). A nomogram was calculated based on age, TBSA and inhalation injury predicting the need for a tracheostomy in severely burned patients.

Conclusion

Using the new nomogram we were able to predict with significantly higher accuracy the need for tracheostomy in severely burned patients. Moreover, tracheostomy is safe and is not associated with higher incidenc of complications, dysphagia or worse outcome.

Multiple organ dysfunction syndrome: Contemporary insights on the clinicopathological spectrum

Multiorgan dysfunction syndrome (MODS) remains a major complication and challenge to treat patients with critical illness in different intensive care unit settings. The exact mechanism and pathophysiology of MODS is complex and remains unexplored. We reviewed the literature from January 2011 to August 2019 to analyze the underlying mechanisms, prognostic factors, MODS scoring systems, organ systems dysfunctions, and the management of MODS. We used the search engines PubMed, MEDLINE, Scopus, and Google Scholar with the keywords "multiple organ dysfunction syndrome," "intensive care units," "multiorgan failure," "MODS scoring system," and "MODS management." The initial search yielded 3550 abstracts, of which 91 articles were relevant to the scope of the present article. A better understanding of a disease course will help differentiate the signs of an intense inflammatory response from the early onset of sepsis and minimize the inappropriate use of medications. This, in turn, will promote organtargeted therapy and prevent occurrence and progression of MODS.

Low-dose Dexamethasone Increases Autophagy in Cerebral Cortical Neurons of Juvenile Rats with Sepsis Associated Encephalopathy

Studies have shown that a certain dose of dexamethasone can improve the survival rate of patients with sepsis, and in sepsis associated encephalopathy (SAE), autophagy plays a regulatory role in brain function. Here, we proved for the first time that small-dose dexamethasone (SdDex) can regulate the autophagy of cerebral cortex neurons in SAE rats and plays a protective role. Cortical neurons were cultured in vitro in a septic microenvironment and a sepsis rat model was established. The small-dose dexamethasone (SdDex) or high-dose dexamethasone (HdDex) was used to intervene in neurons or SAE rats. Through fluorescence microscopy and western blot analysis, the expressions of microtubule-associated protein 1 light chain 3 (LC3), p62/sequestosome1 (p62/SQSTM1), mammalian target of rapamycin (mTOR) signaling pathway related proteins, and apoptosis-related proteins were detected. Theresultsshowthat compared with those in SAE rats, the cortical pathological changes in SAE rats treated with SdDex were improved, and damaged substances were encapsulated and degraded by autophagosomes in neurons. Additionally, similar to neurons in vitro, cortical autophagy was further activated and the mTOR signaling pathway was inhibited. After HdDex treatment, the mTOR signaling pathway in cortex is inhibited, but further activation of autophagy is not obvious, the cortical pathological changes were further worsened and the ultrastructure of neurons was disturbed. Furthermore, the HdDex group exhibited the most obvious apoptosis. SdDex can regulate autophagy of cortical neurons by inhibiting the mTOR signaling pathway and plays a protective role. Brain damage induced by HdDex may be related to the activation of apoptosis.

Proteomic atlas of organ vasculopathies triggered by Staphylococcus aureus sepsis

Sepsis is a life-threatening condition triggered by a dysregulated host response to microbial infection resulting in vascular dysfunction, organ failure and death. Here we provide a semi-quantitative atlas of the murine vascular cell-surface proteome at the organ level, and how it changes during sepsis. Using in vivo chemical labeling and high-resolution mass spectrometry, we demonstrate the presence of a vascular proteome that is perfusable and shared across multiple organs. This proteome is enriched in membrane-anchored proteins, including multiple regulators of endothelial barrier functions and innate immunity. Further, we automated our workflows and applied them to a murine model of methicillin-resistant Staphylococcus aureus (MRSA) sepsis to unravel changes during systemic inflammatory responses. We provide an organ-specific atlas of both systemic and local changes of the vascular proteome triggered by sepsis. Collectively, the data indicates that MRSA-sepsis triggers extensive proteome remodeling of the vascular cell surfaces, in a tissue-specific manner.

Vascular surfaces are rapidly remodeled during systemic inflammatory responses and sepsis. Here, the authors combine in vivo biotinylation and high-resolution mass spectrometry to characterize organ-level changes of the murine vascular cell surface proteome induced by MRSA sepsis.

Multiorgan dysfunction syndrome in feline sepsis: prevalence and prognostic implication

OBJECTIVES

The current study was designed to evaluate the prevalence and prognostic significance of multiorgan dysfunction syndrome (MODS) in cats with sepsis.

METHODS

Cats hospitalised in the intensive care unit of a veterinary university hospital with a diagnosis of sepsis were prospectively enrolled and divided according to disease severity and outcome (survivors; non-survivors). The feline acute patient physiological and laboratory evaluation (APPLE) scores were calculated upon admission, as previously described. Specific criteria to identify selected organ dysfunction (hepatic, renal, respiratory, cardiocirculatory, haemostatic) were adapted from the available human and veterinary literature, and evaluated at baseline and at the end of hospital stay. MODS was defined as the presence of at least two dysfunctional organs simultaneously. Non-parametric statistics were used for comparisons. Univariate and multivariate regression analyses to evaluate significant risk factors for death were carried out. Correlations between variables were assessed by the Spearman's rank correlation coefficient. Significance was set at P <0.05.

RESULTS

A total of 43 cats with heterogeneous sources of sepsis were included. MODS was identified in 25/43 cats upon admission and in 32/43 cats at the end of hospital stay. Regression analyses showed a significantly elevated odds ratio for mortality for the presence of MODS, renal and cardiovascular dysfunction upon admission, as well as for the number of dysfunctional organs. The latter was the only variable retained by the model from the multivariate binary logistic regression analysis. Significant correlations were documented between the number of dysfunctional organs and the APPLE scores.

CONCLUSIONS AND RELEVANCE

MODS is a frequent complication of feline sepsis, and is associated with worse outcomes. In particular, renal and cardiovascular dysfunction significantly increase the odds for death. Hence, systematic screening for organ dysfunction is advocated in cats with sepsis.

Time course of liver mitochondrial function and intrinsic changes in oxidative phosphorylation in a rat model of sepsis

Background

Tissue ATP depletion and oxidative stress have been associated with the severe outcomes of septic shock. One of the compensatory mechanisms to alleviate the sepsis-induced mitochondrial dysfunction could be the increase in oxidative phosphorylation efficiency (ATP/O). We propose to study liver mitochondrial function and oxidative stress and the regulatory mechanism of mitochondrial oxidative phosphorylation efficiency in an animal model of sepsis.

Methods

We induced sepsis in rats by cecal ligation and perforation (CLP). Six, 24, or 36 h following CLP, we measured liver mitochondrial respiration, cytochrome c oxidase activity, and membrane permeability. We determine oxidative phosphorylation efficiency, by measuring ATP synthesis related to oxygen consumption at various exogenous ADP concentrations. Finally, we measured radical oxygen species (ROS) generation by liver mitochondria and mRNA concentrations of UCP2, biogenesis factors, and cytokines at the same end points.

Results

CLP rats presented hypotension, lactic acidosis, liver cytolysis, and upregulation of proinflammatory cytokines mRNA as compared to controls. Liver mitochondria showed a decrease in ATP synthesis and oxygen consumption at 24 h following CLP. A marked uncoupling of oxidative phosphorylation appeared 36 h following CLP and was associated with a decrease in cytochrome c oxidase activity and content and ATP synthase subunit β content (slip mechanism) and an increase in mitochondrial oligomycin-insensitive respiration, but no change in mitochondrial inner membrane permeability (no leak). Upregulation of UCP2 mRNA resulted in a decrease in mitochondrial ROS generation 24 h after the onset of CLP, whereas ROS over-generation associated with slip at cytochrome c oxidase observed at 36 h was concomitant with a decrease in UCP2 mRNA expression.

Conclusions

Despite a compensatory increase in mitochondrial biogenesis factors, liver mitochondrial functions remain altered after CLP. This suggests that the functional compensatory mechanisms reported in the present study (slip at cytochrome c oxidase and biogenesis factors) were not strong enough to increase oxidative phosphorylation efficiency and failed to limit liver mitochondrial ROS over-generation. These data suggest that treatments based on cytochrome c infusion could have a role in mitochondrial dysfunction and/or ROS generation associated with sepsis.

Electronic supplementary material

The online version of this article (10.1186/s40635-018-0197-y) contains supplementary material, which is available to authorized users.

Multi-Scale Analysis of the Toraymyxin Adsorption Cartridge Part II: Computational Fluid-Dynamic Study

Extracorporeal endotoxin removal by means of the Toraymyxin device is based on the ability of polymyxin B to bind endotoxins with a high specificity. The endotoxins/polymyxin molecular interactions were computationally analyzed in a parallel work (Part I). In this paper we investigate with a multi-scale approach the phenomena involving blood and plasma fluid dynamics inside the device. The macro- and mesoscale phenomena were studied by means of 3D models using computational fluid dynamics. The flow behavior in the sorbent material was focused, modeling the sorbent as a homogeneous porous medium at the macroscale level, or accounting for the realistic geometry of its knitted fibers at the mesoscale level. A microscale model was then developed to analyze the behavior of endotoxin molecules subjected to the competition of flow drag and molecular attraction by fibergrafted polymyxin B. The macroscale results showed that a very regular flow field develops in the sorbent, furthermore supplying the peak velocity to be input in the lower-scale model. The mesoscale analysis yielded the realistic range for wall shear stresses (WSSs) acting on fiber walls. With WSS values in the entire range, the results of the microscale analysis demonstrated that the capability of polymyxin B to capture endotoxin molecules from the flow extends at distances one order of magnitude greater than the characteristic distance of the stable intermolecular bond. We conclude that the use of an integrated, multi-scale analysis allows for a comprehensive understanding of the complex mechanisms involved in endotoxin sorption phenomena with immobilized polymyxin B.

Predictors of Mortality in Septic Shock: Findings for 57 Patients Diagnosed on Admission to Emergency or within 24 hours of Admission to Intensive Care

Objective

To identify the risk factors that influence outcome for patients who are diagnosed with septic shock in the emergency department at presentation or within 24 hours after admission to intensive care unit.

Methods

A retrospective study of 57 adult patients with septic shock was conducted between March 1, 2006 and August 31, 2009.

Results

The patients were 23 males and 34 females with a median age of 67 years (20 to 92 years). Thirty-three (58%) of 57 patients died in hospital and 24 (42%) survived. Multivariate analysis identified low blood pH (OR <0.001; 95% CI <0.001-0.53) and low bicarbonate level (OR 0.81; 95% CI 0.70-0.95) at emergency department or intensive care unit admission as useful predictors of 3-day in-hospital mortality. Low blood pH (OR <0.001; 95% CI <0.001-0.05), low bicarbonate level (OR 0.75; 95% CIs 0.61-0.91), long duration of symptoms (OR 1.49; 95% CI 1.04-2.13), high MEDS score (OR 1.56; 95% CIs 1.06-2.30), and high SOFA score (OR 1.57; 95% CI 1.12-2.20) were risk factors for 14-day in-hospital mortality. Renal failure (OR 7.58; 95% CI 1.28-44.77), lower pulmonary tract infection (OR 3.58; 95% CI 1.10-11.58), high MEDS score (OR 1.42; 95% CI 1.05-1.93) and high APACHE II score (OR 1.34; 95% CI 1.13-1.60) were risk factors for 28-day in-hospital mortality.

Conclusions

Several factors signaling poor short-term outcome for this patient group are low blood pH, low serum bicarbonate level, longer duration of symptoms, lower respiratory tract infection and renal failure. MEDS and SOFA scores might be helpful in the ED to stratify patients with septic shock according to mortality risk.

Sepsis and septic shock: Pathogenesis and treatment perspectives

The majority of bacteremias do not develop to sepsis: bacteria are cleared from the bloodstream. Oxygen released from erythrocytes and humoral immunity kill bacteria in the bloodstream. Sepsis develops if bacteria are resistant to oxidation and proliferate in erythrocytes. Bacteria provoke oxygen release from erythrocytes to arterial blood. Abundant release of oxygen to the plasma triggers a cascade of events that cause: 1. oxygen delivery failure to cells; 2. oxidation of plasma components that impairs humoral regulation and inactivates immune complexes; 3. disseminated intravascular coagulation and multiple organs' failure. Bacterial reservoir inside erythrocytes provides the long-term survival of bacteria and is the cause of ineffectiveness of antibiotics and host immune reactions. Treatment perspectives that include different aspects of sepsis development are discussed.

Ulinastatin - a newer potential therapeutic option for multiple organ dysfunction syndrome

Despite significant improvements in medical and surgical management, multiple organ dysfunction syndrome (MODS) or multiple organ failure following conditions such as acute pancreatitis, severe sepsis, and traumatic, hemorrhagic, and endotoxin shocks is still accompanied with a high mortality rate. In light of the crucial role of immunologic derangement recently conceptualized in these conditions, ulinastatin, a urinary trypsin inhibitor, is considered as a potentially beneficial immunomodulator drug for MODS. Mechanisms involving protections against tissue organs and endothelial cell and anti-inflammatory effects by ulinastatin are dependent on the inhibition of polymorphonuclear leukocyte (PMN)-derived elastase, tumor necrosis factor α, and other pro-inflammatory cytokines and interleukins (IL-1, IL-6, and IL-8). Ulinastatin also suppresses the activation of PMN cells, macrophages, and platelets. Derived from these properties, ulinastatin has been investigated as a potential clinical therapy for indications including shock and pancreatitis and approved in Japan and China with ongoing clinical trials around the globe. Off-label potential uses of ulinastatin have been reported in preterm labor and hematological, hepatic, renal, and cardiovascular diseases including vasculitis syndromes such as Kawasaki disease.

Barrier protective effects of 2,4,6-trihydroxy-3-geranyl acetophenone on lipopolysaccharides-stimulated inflammatory responses in human umbilical vein endothelial cells

PHARMOCOLOGICAL RELEVANCE

2,4,6-trihydroxy-3-geranyl acetophenone (tHGA), is a phloroglucinol compound found naturally in Melicope ptelefolia. Melicope ptelefolia has been used traditionally for centuries as natural remedy for wound infections and inflammatory diseases.

AIM OF THE STUDY

Endothelial barrier dysfunction is a pathological hallmark of many diseases and can be caused by lipopolysaccharides (LPS) stimulation. Therefore, this study aims to investigate the possible barrier protective effects of tHGA upon LPS-stimulated inflammatory responses in human umbilical vein endothelial cells (HUVECs).

MATERIALS AND METHODS

HUVECs were pretreated with tHGA prior to LPS stimulation, where inflammatory parameters including permeability, monocyte adhesion and migration, and release of pro-inflammatory mediators were examined. Additionally, the effect of tHGA on F-actin rearrangement and adhesion protein expression of LPS-stimulated HUVECs was evaluated.

RESULTS

It was found that pretreatment with tHGA inhibited monocyte adhesion and transendothelial migration, reduced endothelial hyperpermeability and secretion of prostaglandin E₂ (PGE₂). Additionally, tHGA inhibited cytoskeletal rearrangement and adhesion protein expression on LPS-stimulated HUVECs.

CONCLUSION

As the regulation of endothelial barrier dysfunction can be one of the therapeutic strategies to improve the outcome of inflammation, tHGA may be able to preserve vascular barrier integrity of endothelial cells following LPS-stimulated dysfunction, thereby endorsing its potential usefulness in vascular inflammatory diseases.

Mortality, length of stay, bloodstream and respiratory viral infections in a pediatric intensive care unit

OBJECTIVES

We investigated whether diagnostic categories and presence of infections were associated with increased mortality or length of stay (LOS) in patients admitted to a pediatric intensive care unit (PICU).

METHODS

A retrospective study of all PICU admissions between October 2002 and April 2016 was performed. Oncologic vs nononcologic, trauma/injuries vs nontraumatic, infectious (gram-positive, gram-negative, fungal bloodstream infections, common respiratory viruses) vs noninfectious diagnoses were evaluated for survival and LOS.

RESULTS

Pediatric intensive care unit admissions (n = 2211) were associated with a mortality of 5.3%. Backward binary logistic regression showed that nonsurvival was associated with leukemia (odds ratio [OR], 4.81; 95% confidence interval [CI], 2.2-10.10; P < .0005), lymphoma (OR, 21.34; 95% CI, 3.89-117.16; P < .0005), carditis/myocarditis (OR, 7.91; 95% CI, 1.98-31.54; P = .003), encephalitis (OR, 6.93; 95% CI, 3.27-14.67; P < .0005), bloodstream infections with gram-positive organisms (OR, 5.32; 95% CI, 2.67-10.60; P < .0005), gram-negative organisms (OR, 8.23; 95% CI, 4.10-16.53; P < .0005), fungi (OR, 3.93; 95% CI, 1.07-14.42; P = .039), and pneumococcal disease (OR, 3.26; 95% CI, 1.21-8.75; P = .019). Stepwise linear regression revealed that LOS of survivors was associated with bloodstream gram-positive infection (B = 98.2; 95% CI, 75.7-120.7; P < .0005).

CONCLUSIONS

Patients with diagnoses of leukemia, lymphoma, cardiomyopathy/myocarditits, encephalitis, and comorbidity of bloodstream infections and pneumococcal disease were significantly at risk of PICU mortality. Length of stay of survivors was associated with bloodstream gram-positive infection. The highest odds for death were among patients with leukemia/lymphoma and bloodstream coinfection. As early diagnosis of these childhood malignancies is desirable but not always possible, adequate and early antimicrobial coverage for gram-positive and gram-negative bacteria might be the only feasible option to reduce PICU mortality in these patients. In Hong Kong, a subtropical Asian city, none of the common respiratory viruses were associated with increased mortality or LOS in PICU.

Prevention of Influenza Virus-Induced Immunopathology by TGF-β Produced during Allergic Asthma

Asthma is believed to be a risk factor for influenza infection, however little experimental evidence exists to directly demonstrate the impact of asthma on susceptibility to influenza infection. Using a mouse model, we now report that asthmatic mice are actually significantly more resistant to a lethal influenza virus challenge. Notably, the observed increased resistance was not attributable to enhanced viral clearance, but instead, was due to reduced lung inflammation. Asthmatic mice exhibited a significantly reduced cytokine storm, as well as reduced total protein levels and cytotoxicity in the airways, indicators of decreased tissue injury. Further, asthmatic mice had significantly increased levels of TGF-β1 and the heightened resistance of asthmatic mice was abrogated in the absence of TGF-β receptor II. We conclude that a transient increase in TGF-β expression following acute asthma can induce protection against influenza-induced immunopathology.

Influenza and asthma represent the two major lung diseases in humans. While most studies have focused on exacerbation of asthma symptoms by influenza virus infection, the effects of asthma on susceptibility to influenza virus infections has been far less studied. Using a novel mouse model of asthma and influenza infection, we show that asthmatic mice are highly resistant to primary challenge with the 2009 influenza pandemic strain (CA04) compared to non-asthmatic mice. The increased resistance of asthmatic mice is not due to the enhanced T or B cell immunity but rather, to a strong anti-inflammatory TGF-beta response triggered by asthma. This study is the first to provide a mechanistic explanation for asthma-mediated protection during the 2009 influenza pandemic.

Immune enhancing nutrition in traumatic brain injury - A preliminary study

Traumatic brain injury (TBI) is a major cause of death and disability worldwide. Certain patients appear to benefit when they receive immune enhancing additives, such as glutamine, arginine, and omega-3 fatty acids. We hypothesized that TBI patients given enteral feedings containing these supplements may have improved nutrition measures and infection rates when compared to standard tube feedings. This is a retrospective review of patients from a Level-One trauma center from July 2009 to July 2013. A total of 240 TBI patients received either an immune enhancing nutrition (IEN) formula (n = 126), or a standard formula (SF) (n = 114) based on the attending surgeon's preference. Data collected included demographic information, infection information and outcome measures. Patients were similar in terms of age, ISS, head AIS, and initial prealbumin level. Patients receiving IEN were found to have lower rates of blood stream infections (10.3% vs 19.3%, p < 0.05), whereas pneumonia and UTI rates were similar between groups. In addition, both groups had similar rates of all-cause mortality and hospital length of stay, however IEN patients spent longer in the ICU and on ventilators. In TBI patients receiving IEN, prealbumin levels were higher at the second, third, and fourth week of admission (week 2 - 22.2 vs 17.4, p = 0.006; week 3 - 24.6 vs 20.1, p = 0.04; week 4 - 26.3 vs 22.1, p = 0.19; week 5 - 25.8 vs 20.3, p = 0.21). This study suggests that patients with traumatic brain injury who receive IEN are more likely to have increased prealbumin levels perhaps reflecting improved nutrition throughout their hospital stay and may show some benefit in rates of infections, particularly in bacteremia.

Pretreatment with magnesium ameliorates lipopolysaccharide-induced liver injury in mice

BACKGROUND

Lipopolysaccharide (LPS), a component of the outer membrane of Gram-negative bacteria, is involved in the pathogenesis of sepsis. LPS administration induces systemic inflammation that mimics many of the initial clinical features of sepsis and has deleterious effects on several organs including the liver and eventually leading to septic shock and death. The present study aimed to investigate the protective effect of magnesium (Mg), a well known cofactor in many enzymatic reactions and a critical component of the antioxidant system, on hepatic damage associated with LPS-induced endotoxima in mice.

METHODS

Mg (20 and 40mg/kg, po) was administered for 7 consecutive days. Systemic inflammation was induced 1h after the last dose of Mg by a single dose of LPS (2mg/kg, ip) and 3h thereafter plasma was separated, animals were sacrificed and their livers were isolated.

RESULTS

LPS-treated mice suffered from hepatic dysfunction revealed by histological observation, elevation in plasma transaminases activities, C-reactive protein content and caspase-3, a critical marker of apoptosis. Liver inflammation was evident by elevation in liver cytokines contents (TNF-α and IL-10) and MPO activity. Additionally, oxidative stress was manifested by increased liver lipoperoxidation, glutathione depletion, elevated total nitrate/nitrite (NOx) content and glutathione peroxidase (GPx) activity. Pretreatment with Mg largely mitigated these alternations.

CONCLUSION

Pretreatment with Mg protects the liver from the acute injury which occurs shortly after septicemia.

Expression levels of tumor necrosis factor-α and the corresponding receptors are correlated with trauma severity

This study investigated the plasma levels of tumor necrosis factor α (TNF-α) and the expression levels of TNF receptors (TNFRs) in patients with multiple trauma, together with the association between the levels of this cytokine and these cytokine receptors with the severity of traumatic injury. Blood samples were obtained from 60 multiple trauma patients at hospital admission (within 2 h of injury), and 6–8 h and 1–5 days after admission. The plasma levels of TNF-α and TNFR1/TNFR2 were detected using enzyme immunoassay. TNFR1 and TNFR2 expression levels on leukocytes, including neutrophils, lymphocytes and monocytes, were determined by flow cytometry. Clinical parameters were determined by injury severity score (ISS). At hospital admission, the plasma TNF-α and soluble TNFR levels in the trauma patients were elevated compared with those of healthy controls. Increased expression levels of TNFR1 and TNFR2 were also detected on leukocytes, particularly on lymphocytes and monocytes. The expression levels of the cytokine and the corresponding receptors were correlated with the ISS. TNF-α and TNFR expression levels remained significantly elevated for up to the third to fifth day following the traumatic injury. In the trauma patients, increased levels of TNF-α and TNFRs were correlated with the severity of traumatic injury in the early post-injury period, supporting the hypothesis that trauma-provoked organ dysfunction may be caused by an overwhelming auto-destructive inflammatory response.

Acute pancreatitis due to scrub typhus

Scrub typhus is endemic in large parts of India and can cause multi-organ failure and death. Acute pancreatitis as a complication is very rare and is potentially fatal. This case series describes seven adult patients who presented with an acute febrile illness and were diagnosed to have scrub typhus with acute pancreatitis. The mean age of the seven patients with acute pancreatitis was 49.4 years, and mean duration of fever prior to presentation was 7.7 days. All seven patients had abdominal pain, and three had a pathognomonic eschar. The mean serum lipase level was 1,509 U/L (normal value: <190 U/L) and the mean serum amylase level was 434 U/L (normal value: <200 U/L). Six patients had evidence of multi-organ dysfunction. Hematological and respiratory system dysfunction was seen in five patients, hepatic and renal dysfunction in four, and central nervous system dysfunction in three patients. Three patients who had ≥4 organs involved, died (mortality rate: 42.8%). Our case series shows that pancreatitis in scrub typhus is an extremely rare complication and when present, is associated with increased mortality (42.8%). Physicians may be familiar with the various complications of scrub typhus but less so with acute pancreatitis and hence may be underdiagnosed.

A novel hypothesis comprehensively explains shock, heart failure and aerobic exhaustion through an assumed central physiological control of the momentary cardiovascular performance reserve

BACKGROUND

Heart failure (HF) and shock are incomprehensively understood, inconclusively defined and lack a single conclusive test. The proceedings that preceded and triggered clinical manifestations are occult. The relationships in between different shock and HF types and between each HF type and its matched shock are poorly understood.

THE ASSUMED HYPOTHESIS

We suggest that HF and shock are attributed to a momentary cardiovascular performance reserve - "the reserve". The reserve is controlled through an assumed central physiological mechanism that continuously detects and responds accordingly--"the reserve control". The assumed reserve is maximal at rest, and decreases with aerobic activity. When it decreases to a given threshold the reserve control alerts by induces manifestations of dyspnea and fatigue enforcing activity decrease, follow which the manifestations dissolve. HF is a condition of low reserve at baseline; hence, fatigue and dyspnea are frequently experienced following mild activity. Shock is assumed to occur when the cardiovascular reserve deteriorates below a sustainable limit where the reserve control induces a salvage-sacrifice response, preserving vital organ perfusion while impairing microcirculation effective perfusion in non-vital organ in which it causes cellular hypoxia followed by the familiar devastating cascade of events seen in shock.

DISCUSSION AND CONCLUSIONS

The hereby hypothesis may comprehensively explain the heart failure - shock puzzle as no alternative theory had ever succeeded. It provides the missing link between the different types of HF as of shock and in between. The hypothesis poses a great prove challenge but opens new research and clinical possibilities.

Prolonged non-survival in PICU: does a do-not-attempt-resuscitation order matter

Background

Etiologies of pediatric intensive care unit (PICU) mortality are diverse. This study aimed to investigate the pattern of PICU mortality in a regional trauma center, and explore factors associated with prolonged non-survival.

Methods

Demographic data of all PICU deaths in a regional trauma center were analyzed. Factors associated with prolonged nonsurvival (length of stay) were investigated with univariate log rank and multivariate Cox-Regression forward stepwise tests.

Results

There were 88 deaths (males 61%; infants 23%) over 10 years (median PICU stay = 3.5 days, interquartile range: 1 and 11 days). The mean annual mortality rate of PICU admissions was 5.8%. Septicemia with gram positive, gram negative and fungal pathogens were present in 13 (16%), 13 (16%) and 4 (5%) of these patients, respectively. Viruses were isolated in 25 patients (28%). Ninety percent of these 88 patients were ventilated, 75% required inotropes, 92% received broad spectrum antibiotic coverage, 32% received systemic corticosteroids, 56% required blood transfusion and 39% received anticonvulsants. Thirty nine patients (44%) had a DNAR (Do-Not-Attempt-Resuscitation) order with their deaths at the PICU. Comparing with non-trauma category, trauma patients had higher mortality score, no premorbid disease, suffered asystole preceding PICU admission and subsequent brain death. Oncologic conditions were the most prevalent diagnosis in the non-trauma category. There was no gunshot or asthma death in this series. Prolonged non-survival was significantly associated with DNAR, fungal infections, and mechanical ventilation but negatively associated with bacteremia.

Conclusions

Death in the PICU is a heterogeneous event that involves infants and children. Resuscitation was not attempted at the time of their deaths in nearly half of the patients in honor of parents’ wishes. Parents often make DNAR decision when medical futility becomes evident. They could be reassured that DNAR did not mean “abandoning” care. Instead, DNAR patients had prolonged PICU stay and received the same level of PICU supports as patients who did not respond to cardiopulmonary resuscitation.

Systemic inflammatory response syndrome (SIRS): where did it come from and is it still relevant today?

The concept of a systemic inflammatory response syndrome (SIRS) to describe the complex pathophysiologic response to an insult such as infection, trauma, burns, pancreatitis, or a variety of other injuries came from a 1991 consensus conference charged with the task of developing an easy-to-apply set of clinical parameters to aid in the early identification of potential candidates to enter into clinical trials to evaluate new treatments for sepsis. There was recognition that a diverse group of injuries produced a common inflammatory response in the host and provided attractive targets for new anti-inflammatory molecules designed to prevent further propagation and/or provide specific treatment. Effective application of these new anti-inflammatory strategies necessitated identification of early clinical markers that could be assessed in real-time and were likely to define a population of patients that would have a beneficial response to the targeted intervention. It was felt that early clinical manifestations might be more readily available to clinicians than more sophisticated and specific assays for inflammatory substances that were systemically released by the network of injurious inflammatory events. Therefore, the early definition of a systemic inflammatory response syndrome (SIRS) was built upon a foundation of basic clinical and laboratory abnormalities that were readily available in almost all clinical settings. With further refinement, it was hoped, that this definition would have a high degree of sensitivity, coupled with a reasonable degree of specificity. This manuscript reviews the derivation, application, utilization, potential benefits, and speculation regarding the future of the SIRS definition.

The changing immune system in sepsis: is individualized immuno-modulatory therapy the answer?

Sepsis remains the leading cause of death in most intensive care units. Advances in understanding the immune response to sepsis provide the opportunity to develop more effective therapies. The immune response in sepsis can be characterized by a cytokine-mediated hyper-inflammatory phase, which most patients survive, and a subsequent immune-suppressive phase. Patients fail to eradicate invading pathogens and are susceptible to opportunistic organisms in the hypo-inflammatory phase. Many mechanisms are responsible for sepsis-induced immuno-suppression, including apoptotic depletion of immune cells, increased T regulatory and myeloid-derived suppressor cells, and cellular exhaustion. Currently in clinical trial for sepsis are granulocyte macrophage colony stimulating factor and interferon gamma, immune-therapeutic agents that boost patient immunity. Immuno-adjuvants with promise in clinically relevant animal models of sepsis include anti-programmed cell death-1 and interleukin-7. The future of immune therapy in sepsis will necessitate identification of the immunologic phase using clinical and laboratory parameters as well as biomarkers of innate and adaptive immunity.

Near-infrared spectroscopy StO2 monitoring to assess the therapeutic effect of drotrecogin alfa (activated) on microcirculation in patients with severe sepsis or septic shock

Background

Sepsis is a leading cause of death despite appropriate management. There is increasing evidence that microcirculatory alterations might persist independently from macrohemodynamic improvement and are related to clinical evolution. Future efforts need to be directed towards microperfusion monitoring and treatment. This study explored the utility of thenar muscle oxygen saturation (StO₂) and its changes during a transient vascular occlusion test (VOT) to measure the microcirculatory response to drotrecogin alfa (activated) (DrotAA) in septic patients.

Methods

A prospective, observational study was performed in three general intensive care units at three university hospitals. We studied 58 patients with recent onset of severe sepsis or septic shock and at least two organ dysfunctions. Thirty-two patients were treated with DrotAA and 26 were not treated because of formal contraindication. StO₂ was monitored using near-infrared spectroscopy (NIRS), and VOT was performed to obtain deoxygenation (DeOx) and reoxygenation (ReOx) slopes. Measurements were obtained before DrotAA was started and were repeated daily for a 96-hour period.

Results

Patients’ characteristics, outcome, severity, and baseline values of StO₂, DeOx, and ReOx did not differ between groups. Treated patients significantly improved DeOx and ReOx values over time, whereas control patients did not. In treated patients, ReOx improvements were correlated to norepinephrine dose reductions. Early clinical response (SOFA improvement after 48 hours of treatment) was not associated to changes in VOT-derived slopes. In the treated group, the relative improvement of DeOx within 48 hours was able to predict mortality (AUC 0.91, p < 0.01).

Conclusions

In patients with severe sepsis or septic shock, DrotAA infusion was associated with improvement in regional tissue oxygenation. The degree of DeOx amelioration after 2 days in treated patients predicted mortality with high sensitivity and specificity. Thus, StO₂ derived variables might be useful to evaluate the microcirculatory response to treatment of septic shock.

Remifentanil ameliorates intestinal ischemia-reperfusion injury

Background

Intestinal ischemia-reperfusion injury (IRI) can occur in clinical scenarios such as organ transplantation, trauma and cardio-pulmonary bypass, as well as in neonatal necrotizing enterocolitis or persistent ductus arteriosus. Pharmacological protection by pretreating (“preconditioning”) with opioids attenuates IRI in a number of organs. Remifentanil appears particularly attractive for this purpose because of its ultra-short duration of action and favorable safety profile. To date, little is known about opioid preconditioning of the intestine.

Methods

Young adult C57BL/6J mice were randomly assigned to receive tail vein injections of 1 μg/kg of remifentanil or normal saline and underwent either ischemia-reperfusion of the intestine or a sham laparotomy. Under isoflurane anesthesia, the mice were subjected to intestinal ischemia-reperfusion by occlusion (clamping) of the superior mesenteric artery for 30 min, followed by unclamping and 60 min of reperfusion. After completion of this protocol, tissue injury and lipid peroxidation in jejunum and ileum were analyzed by histology and malondialdehyde (MDA), respectively. Systemic interleukin (IL)-6 was determined in the plasma by ELISA.

Results

Pretreatment with remifentanil markedly reduced intestinal IRI (P < 0.001): In the ileum, we observed a more than 8-fold decrease in injured villi (4% vs 34% in saline-pretreated animals). In fact, the mucosa in the remifentanil group was as healthy as that of sham-operated animals. This protective effect was not as pronounced in the jejunum, but the percentage of damaged villi was still reduced considerably (18% vs 42%). There was up to 3-fold more tissue MDA after intestinal ischemia-reperfusion than after sham laparotomy, but this increase in lipid peroxidation was prevented by preconditioning with remifentanil (P < 0.05). The systemic inflammatory response triggered by intestinal IRI was significantly attenuated in mice pretreated with remifentanil (159 vs 805 pg/ml of IL-6 after saline pretreatment, with 92 pg/ml in the sham groups). After sham operations, no difference was detected between the saline- and remifentanil-pretreatments in any of the parameters investigated.

Conclusion

Preconditioning with remifentanil attenuates intestinal IRI and the subsequent systemic inflammatory response in mice. We therefore suggest that prophylaxis with this ultra-short-acting opioid may be advantageous in various clinical scenarios of human IRI.

Abnormalities in glucose homeostasis in critically ill children

OBJECTIVES

To study the prevalence of hyperglycemia (blood glucose >126 mg/dL [>7 mmol/L]) in critically ill children older than 1 month in the first week of PICU stay and to determine its effect on mortality, organ dysfunction, and the length of PICU stay. We also determined the prevalence of glucose variability and hypoglycemia and studied their effect on mortality and morbidity.

DESIGN

Prospective, observational cohort study.

SETTING

PICU of a tertiary care hospital.

PATIENTS

Children admitted to the PICU older than 1 month of age (January 2009 to June 2010).

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Blood glucose values, clinical and laboratory data to calculate Pediatric Index of Mortality-2 and Pediatric Logistic Organ Dysfunction scores, caloric and carbohydrate intake, vasoactive drugs, and steroid and insulin usage for upto 7 days were recorded. Out of 170 critically ill children admitted to the PICU, hyperglycemia (blood glucose >126 mg/dL [7 mmol/L]) was observed in 78.24% children (95% confidence interval 72-84.4). On adjusted analysis, blood glucose level >180 mg/dL (10 mmol/L) was associated with increased mortality. Blood glucose >126 mg/dL (7 mmol/L) was not associated with mortality or PICU length of stay but was associated with multiple organ dysfunction. Hypoglycemia and glucose variability also occurred frequently in critically ill children; these were associated with occurrence of multiple organ failure.

CONCLUSIONS

Hyperglycemia (blood glucose >126 mg/dL [7 mmol/L]) is common in critically ill children, and values >180 mg/dL (10 mmol/L) are associated with mortality. We also noted that hyperglycemia, hypoglycemia (blood glucose <40 mg/dL [2.2 mmol/L]), and glucose variability were associated with multiple organ dysfunction.

G-protein coupled receptor kinase 5 mediates lipopolysaccharide-induced NFκB activation in primary macrophages and modulates inflammation in vivo in mice

G-protein coupled receptor kinase-5 (GRK5) is a serine/threonine kinase discovered for its role in the regulation of G-protein coupled receptor signaling. Recent studies have shown that GRK5 is also an important regulator of signaling pathways stimulated by non-GPCRs. This study was undertaken to determine the physiological role of GRK5 in Toll-like receptor-4-induced inflammatory signaling pathways in vivo and in vitro. Using mice genetically deficient in GRK5 (GRK5(-/-) ) we demonstrate here that GRK5 is an important positive regulator of lipopolysaccharide (LPS, a TLR4 agonist)-induced inflammatory cytokine and chemokine production in vivo. Consistent with this role, LPS-induced neutrophil infiltration in the lungs (assessed by myeloperoxidase activity) was markedly attenuated in the GRK5(-/-) mice compared to the GRK5(+/+) mice. Similar to the in vivo studies, primary macrophages from GRK5(-/-) mice showed attenuated cytokine production in response to LPS. Our results also identify TLR4-induced NFκB pathway in macrophages to be selectively regulated by GRK5. LPS-induced IκBα phosphorylation, NFκB p65 nuclear translocation, and NFκB binding were markedly attenuated in GRK5(-/-) macrophages. Together, our findings demonstrate that GRK5 is a positive regulator of TLR4-induced IκBα-NFκB pathway as well as a key modulator of LPS-induced inflammatory response.

Impact of early enteral nutrition on in-hospital mortality in patients with hypertensive intracerebral hemorrhage

OBJECTIVE

We conducted this study to evaluate the clinical impact of early enteral nutrition (EN) on in-hospital mortality and outcome in patients with critical hypertensive intracerebral hemorrhage (ICH).

METHODS

We retrospectively analyzed 123 ICH patients with Glasgow Coma Scale (GCS) score of 3-12. We divided the subjects into two groups : early EN group (< 48 hours, n = 89) and delayed EN group (≥ 48 hours, n = 34). Body weight, total intake and output, serum albumin, C-reactive protein, infectious complications, morbidity at discharge and in-hospital mortality were compared with statistical analysis.

RESULTS

The incidence of nosocomial pneumonia and length of intensive care unit stay were significantly lower in the early EN group than in the delayed EN group (p < 0.05). In-hospital mortality was less in the early EN group than in the delayed EN group (10.1% vs. 35.3%, respectively; p = 0.001). By multivariate analysis, early EN [odds ratio (OR) 0.229, 95% CI : 0.066-0.793], nosocomial pneumonia (OR = 5.381, 95% CI : 1.621-17.865) and initial GCS score (OR = 1.482 95% CI : 1.160-1.893) were independent predictors of in-hospital mortality in patients with critical hypertensive ICH.

CONCLUSION

These findings indicate that early EN is an important predictor of outcome in patients with critical hypertensive ICH.

Phosphorylation of extracellular signal-regulated kinase (ERK)-1/2 Is associated with the downregulation of peroxisome proliferator-activated receptor (PPAR)-γ during polymicrobial sepsis

Peroxisome proliferator-activated receptor (PPAR)-γ is a ligand-activated transcription factor and regulates inflammation. Posttranslational modifications regulate the function of PPARγ, potentially affecting inflammation. PPARγ contains a mitogen-activated protein kinase (MAPK) site, and phosphorylation by extracellular signal-regulated kinase (ERK)-1/2 leads to inhibition of PPARγ. This study investigated the kinetics of PPARγ expression and activation in parenchymal and immune cells in sepsis using the MAPK/ERK kinase (MEK)-1 inhibitor, an upstream kinase of ERK1/2. Adult male Sprague Dawley rats were subjected to polymicrobial sepsis by cecal ligation and puncture. Rats received intraperitoneal injection of vehicle or the MEK1 inhibitor PD98059 (5 mg/kg) 30 min before cecal ligation and puncture. Rats were euthanized at 0, 1, 3, 6 and 18 h after cecal ligation and puncture. Control animals used were animals at time 0 h. Lung, plasma and peripheral blood mononuclear cells (PBMCs) were collected for biochemical assays. In vehicle-treated rats, polymicrobial sepsis resulted in significant lung injury. In the lung and PBMCs, nuclear levels of PPARγ were decreased and associated with an increase in phosphorylated PPARγ and phosphorylated ERK1/2 levels. Treatment with the MEK1 inhibitor increased the antiinflammatory plasma adipokine adiponectin, restored PPARγ expression in PBMCs and lung, and decreased lung injury. The inflammatory effects of sepsis cause changes in PPARγ expression and activation, in part, because of phosphorylation of PPARγ by ERK1/2. This phosphorylation can be reversed by ERK1/2 inhibition, thereby improving lung injury.

Different types of cell death induced by enterotoxins

The infection of bacterial organisms generally causes cell death to facilitate microbial invasion and immune escape, both of which are involved in the pathogenesis of infectious diseases. In addition to the intercellular infectious processes, pathogen-produced/secreted enterotoxins (mostly exotoxins) are the major weapons that kill host cells and cause diseases by inducing different types of cell death, particularly apoptosis and necrosis. Blocking these enterotoxins with synthetic drugs and vaccines is important for treating patients with infectious diseases. Studies of enterotoxin-induced apoptotic and necrotic mechanisms have helped us to create efficient strategies to use against these well-characterized cytopathic toxins. In this article, we review the induction of the different types of cell death from various bacterial enterotoxins, such as staphylococcal enterotoxin B, staphylococcal alpha-toxin, Panton-Valentine leukocidin, alpha-hemolysin of Escherichia coli, Shiga toxins, cytotoxic necrotizing factor 1, heat-labile enterotoxins, and the cholera toxin, Vibrio cholerae. In addition, necrosis caused by pore-forming toxins, apoptotic signaling through cross-talk pathways involving mitochondrial damage, endoplasmic reticulum stress, and lysosomal injury is discussed.

Commensal microflora induce host defense and decrease bacterial translocation in burn mice through toll-like receptor 4

Background

Major burn is associated with decreased gut barrier function and increased bacterial translocation (BT). This study is to investigate whether commensal microflora induce host defense and decrease BT in burn mice.

Methods

First, we treated Wild type (WT) mice with antibiotics in drinking water for 4 weeks to deplete gut commensal microflora. At week 3, drinking water was supplemented with lipopolysaccharide (LPS); a ligand for TLR4, to trigger TLRs in gut. The intestinal permeability, glutathione level, NF-κB DNA-binding activity, TLR4 expression of intestinal mucosa, BT to mesenteric lymph nodes (MLNs), and bacterial killing activity of peritoneal cells were measured after thermal injury. Second, lung of animals were harvested for MPO activity and TNFα mRNA expression assay. Third, WT animals were treated with oral antibiotics with or without LPS supplement after burn. At 48 hr after burn, TLR4 expression of intestinal mucosa and bacterial killing activity of cells were examined. Finally, bacterial killing activity and BT to MLNs after thermal injury in C3H/HeJ (TLR4 mutant) mice were measured.

Results

Burn induced BT to MLNs in WT mice. Commensal depletion decreased TLR4 expression as well as NF-κB activation of intestine, myeloperoxidase (MPO) activity as well as TNFα expression of lung, and bacterial killing activity of peritoneal cells. Oral LPS supplement markedly reduced 81% of burn-induced BT and increased TLR4 expression, MPO activity of lung, as well as bacterial killing activity of peritoneal cells. LPS supplement did not change BT or bacterial killing activity in C3H/HeJ mice.

Conclusions

Collectively, commensal microflora induce TLR4 expression of intestine and bacterial killing activity of inflammatory cells in burn. TLR4 ligand increases bacterial killing activity and decreases burn-induced BT. Taken together with the abolition of LPS effect in TLR4 mutant mice, we conclude that commensal microflora induce host defense and decrease bacterial translocation in burn mice through toll-like receptor 4.

The effect of Baihu Decoction (白虎汤) on blood glucose levels in treating systemic inflammatory response syndrome

In this paper we investigated the mechanisms of Baihu Decoction ((白虎汤, BH) and Baihu with Radix Ginseng (BHG) in treating systemic inflammatory response syndrome (SIRS) and sepsis in humans and animals. By reviewing published data on the effects of BH and BHG and the control of blood glucose in treating SIRS and sepsis, we found that (1) BH and BHG were beneficial in the treatment of SIRS and sepsis in humans and animals; (2) BH and BHG also had great effect in lowering blood glucose level; and (3) the tight control of blood glucose during critical illness substantially improved the outcome. Considering these data together, we hypothesize that one of the major mechanisms of BH and BHG in treating SIRS and sepsis is to lower the blood glucose level. The findings also suggest that the application of BH and BHG can extend to many acute illnesses and injuries, which commonly cause hyperglycemia.

ICU admissions after actual or planned hospital discharge: incidence, clinical characteristics, and outcomes in patients with cancer

BACKGROUND

Unexpected ICU admissions may result from early or premature discharge from the hospital. We sought to determine the incidence, clinical characteristics, and outcomes of patients admitted to the ICU after actual or planned hospital discharge and to analyze whether the need for ICU admission was related or unrelated to the associated hospitalization.

METHODS

We retrospectively reviewed all adult ICU admissions between January 2004 and December 2006 at a tertiary care cancer center and identified the following two groups of patients: those patients admitted directly to the ICU within 48 h of actual hospital discharge (group A); and those patients admitted to the ICU within 48 h of planned hospital discharge (group B).

RESULTS

Of 60,462 patients discharged from the hospital during the study period, 826 patients (1.4%) required readmission to the hospital within 48 h of discharge; of these, 13 patients (1.5%) were admitted directly to the ICU (group A). An additional 12 patients were admitted to the ICU within 48 h of a planned hospital discharge (group B). The majority of these 25 patients (68%) [groups A and B] required ICU admission for a condition that was related to the previous or current hospitalization. The overall hospital mortality rate for both groups was 16%.

CONCLUSIONS

A small, but unique group of patients is admitted to the ICU within 48 h of actual or planned hospital discharge. Worsening of the underlying condition that necessitated the previous or current hospitalization often is the reason for ICU admission. Whether ICU admission could have been prevented by continued hospital care or improved diagnostic evaluation during the prior or current hospitalization requires further study.

Vaccine preventable infections and multiple organ dysfunction syndrome in critically ill children in China

BACKGROUND

Multiple organ dysfunction syndrome (MODS) is a major cause of mortality in PICUs in industrialized countries. As developing countries become more advanced, PICU care comes into reach. The aim of this study was to examine MODS in a PICU in China in comparison with other countries.

METHODS

A retrospective 5-year audit (2001-2006) of MODS cases in a 6-bed PICU in the Second Hospital of Lanzhou University, China.

RESULTS

Of the 332 PICU patients, 176 (53%) had MODS; the mean age was 35 months, and 60% were <1 year of age. Infectious diseases were the predominant factor underlying MODS (128/176; 73%) with 24% attributable to potentially vaccine preventable infections (14 to Haemophilus influenzae b, 13 to Streptococcus pneumoniae, and 4 to Neisseria meningitidis). The case fatality rate for MODS was 49% with no difference between infectious or noninfectious causes (48% vs. 52%; P > 0.05). The frequency of organ dysfunction in MODS was in decreasing order: respiratory (95%), cardiovascular (89%), gastrointestinal (39%), neurologic (35%), hematologic (16%), renal (14%), and hepatic (4%) systems. Mortality rose with increasing number of organs involved. Gastrointestinal system failure was more common in MODS caused by infection than noninfection (45% vs. 23%; P <0.01) and had a higher mortality (72% vs. 34%; P < 0.001). The case fatality rate for MODS in this study was comparable to rates in other developing countries but higher than in industrialized countries.

CONCLUSIONS

MODS is a major cause of mortality in PICU patients in China. In China, infection-related MODS PICU cases could potentially be reduced to rates closer to those in industrialized countries, if conjugated H. influenzae b and conjugated pneumococcal vaccines were introduced into routine practice.

Direct hemoperfusion with a cytokine-adsorbing device for the treatment of persistent or severe hypercytokinemia: a pilot study

BACKGROUND/AIMS

Cytokine overproduction has been noted during the aggravation of clinical conditions. Countermeasures to control hypercytokinemia are therefore important in critical care. We investigated the clinical efficacy of hemoadsorption therapy using a new cytokine-adsorbing device in critically ill patients with persistent or severe hypercytokinemia.

METHODS

Direct hemoperfusion using the CYT-860, a cytokine-adsorber column (CYT-860-DHP), was performed in critically ill patients with hypercytokinemia. To evaluate the efficacy of CYT-860-DHP, changes in pathological and clinical parameters were examined.

RESULTS

Seven patients with hypercytokinemia and a SOFA score of > or = 5 underwent CYT-860-DHP treatment. Four patients survived 28 days after CYT-860-DHP treatment. Significant decreases in blood levels of cytokines were observed. PaO2/F(I)O2 improved significantly.

CONCLUSION

The possibility that CYT-860-DHP treatment can reduce blood cytokine levels and thereby improve the general condition of patients was suggested. These findings warrant the initiation of a prospective randomized trial to evaluate the clinical efficacy of CYT-860-DHP treatment.

Is increased mortality associated with post-operative infections after leukocytes containing red blood cell transfusions in cardiac surgery? An extended analysis

In two randomized trials in cardiac surgery we observed that leukoreduced allogeneic red blood cell (RBC) transfusions (LR) compared with standard buffy-coat-depleted RBC transfusions (BCD) resulted in lower rates of post-operative infections and mortality. To unravel whether this comprises two independent side effects or could be related complications of allogeneic leukocytes, we performed a re-analysis on the patients of these two trials. For all analyses, homogeneity tests were shown not to be significant. Data on characteristics of post-operative infections, nature of microorganisms, number of transfusions and causes of death in both studies were subjected to an integrated analysis. In both studies combined, 1085 patients had been assigned to prestorage leukoreduced RBCs (LR, n= 542) or standard buffy-coat-depleted RBCs (BCD, n= 543). Post-operative infections were significantly higher in the BCD group [BCD: 34.2% vs. LR: 24.0%, common odds ratios (COR): 1.65, 95% confidence interval (CI): 1.27-2.15], whereas the species of cultured microorganisms and the type of the infections were similar in both randomization arms. Mortality with infections was significantly higher in patients receiving BCD compared with LR (BCD: 5.5% vs. LR: 2.2%, COR: 2.59, 95% CI: 1.31-5.14), whereas mortality without infections was similar in both arms (BCD: 3.9% vs. LR: 3.1%, COR: 1.24, 95% CI: 0.65-2.38). The only cause of death that differed significantly between BCD and LR was the combination of multiple organ dysfunction syndrome with infections. This re-analysis shows that transfusion of leukocytes containing RBCs during cardiac surgery may be associated with more infections with fatal outcome. This should be confirmed in a larger extended analysis or a prospective study.

Recognizing and Managing Severe Sepsis: A Common and Deadly Threat

Through a literature review, the epidemiology and pathophysiology, including alterations in inflammation, coagulation, and impaired fibrinolysis that occur in the course of severe sepsis, is presented. Treatment guidelines that are evidence-based and endorsed by 11 professional societies representing multispecialty groups are described. Severe sepsis is common; 750,000 cases are estimated to occur annually in the United States. The mortality rate for severe sepsis still ranges from 30 to 50%, and is as high as 80 to 90% for septic shock and multiple organ dysfunction. Severe sepsis exists along a continuum initiated by a localized infection that triggers a systemic response. A cascade of inflammation and activation of the coagulation system associated with impaired fibrinolysis leads to alterations in microvascular circulation associated with organ dysfunction, severe sepsis, multiple organ dysfunction syndrome, and death. In an attempt to improve care and reduce mortality, the Surviving Sepsis Campaign and The Institute for Healthcare Improvement (IHI) have created two sepsis treatment bundles.

Digital output volumetric pulmonary artery catheters eliminate interoperator interpretation variability and improve consistency of treatment decisions

BACKGROUND

The pulmonary artery catheter (PAC) has been fraught with controversy over issues of safety and impact on outcomes variables for many years. Multiple attempts to quantify the utility of this diagnostic instrument have failed to resolve the matter. Previous investigations have focused on either quantifying inter-rater variability of waveform output interpretation from PACs or on clinical outcomes when PACs are used in care. We tested the hypothesis that the true link between a diagnostic tool and outcomes is treatment selection, and an instrument that minimizes or eliminates the need for data interpretation would also minimize the variability of treatment selections.

STUDY DESIGN

We performed a prospective, single institutional, single blinded survey study.

RESULTS

The inter-rater variability of waveform interpretation among all raters was notable (p < 0.01); for continuous end diastolic volume index interpretation, there was no notable inter-rater variability (p=1.0). Inter-rater variability of treatment selections based on waveform interpretation was notable for all raters (p < 0.01). Continuous end diastolic volume index data presentation of hemodynamic status did not result in notable inter-rater variability in treatment selections (p=0.10). Treatment choices based on continuous end diastolic volume index among raters with 5 or more years of experience are not different from clinical practice guideline-directed choices (p > 0.05), independent of patient ventilator status.

CONCLUSIONS

Digital output volumetric PACs eliminate inter-rater variability of data interpretation, decrease inter-rater variability of data-driven treatment selections, and improve rater agreement with clinical practice guidelines when compared with traditional waveform output PACs.

Aldose reductase mediates the lipopolysaccharide-induced release of inflammatory mediators in RAW264.7 murine macrophages

Abnormal production of inflammatory cytokines and chemokines is a key feature of bacterial endotoxin, lipopolysaccharide (LPS)-induced inflammation, and cytotoxicity; however, the mechanisms regulating production of inflammatory markers remain unclear. Herein, we show that inhibition of the aldehyde-metabolizing enzyme aldose reductase (AR; AKR1B3) modulates NF-kappaB-dependent activation of inflammatory cytokines and chemokines in mouse serum, liver, heart, and spleen. Pharmacological inhibition or small interfering RNA ablation of AR prevented the biosynthesis of tumor necrosis factor-alpha, interleukin 1beta, interleukin-6, macrophage-chemoattractant protein-1, and cyclooxygenase-2 and prostaglandin E(2) in LPS-activated RAW264.7 murine macrophages. The AR inhibition or ablation significantly attenuated LPS-induced activation of protein kinase C (PKC) and phospholipase C (PLC), nuclear translocation of NF-kappaB, and phosphorylation and proteolytic degradation of IkappaBalpha in macrophages. Furthermore, treatment of macrophages with 4-hydroxy-trans-2-nonenal (HNE), and cell-permeable esters of glutathionyl-4-hydroxynonanal (GS-HNE) and glutathionyl-1,4-dihydroxynonane (GS-DHN) activated NF-kappaB and PLC/PKC. Pharmacological inhibition or antisense ablation of AR that catalyzes the reduction of GS-HNE to GS-DHN prevented PLC, PKC, IKKalpha/beta, and NF-kappaB activation caused by HNE and GS-HNE, but not by GS-DHN, suggesting that reduced GS-lipid aldehydes catalyzed by AR propagate LPS-induced production of inflammatory markers. Collectively, these data provide evidence that inhibition of AR may be a significant therapeutic approach in preventing bacterial endotoxin-induced sepsis and tissue damage.