Effects of a peripheral cholinesterase inhibitor on cytokine production and autonomic nervous activity in a rat model of sepsis.

PURPOSE: Recently, cholinergic anti-inflammatory pathway manipulation has been proposed as a new strategy to control cytokine production in sepsis. We investigated whether hypercytokinemia can be controlled via this pathway in an animal model of sepsis, with concomitant monitoring of autonomic nervous activity involving heart rate variability (HRV) analysis of electrocardiographic R-R intervals. METHODS: Sixty-eight adult male Sprague-Dawley rats were used (28 for examination of cytokine production and autonomic nervous activity; 40 for survival analysis). Each part of the study involved four animal groups, including two control groups without drug administration. Sepsis was induced by cecal ligation and puncture (CLP). Distigmine bromide, a peripheral, non-selective cholinesterase inhibitor (0.01mg/kg), was administered subcutaneously 90 min after surgery. Continuous electrocardiograms were recorded for 5 min before and after surgery (at intervals of 5h) in CLP and sham-operated animals for HRV analysis. Blood samples were collected 20 h after surgery for serum cytokine and catecholamine assay. RESULTS: On HRV analysis, distigmine inhibited reduction of total power and high-frequency components in CLP animals (P<0.05). Distigmine significantly inhibited cytokine induction (IL-6 and IL-10) (P<0.01) as well as increase in serum levels of noradrenaline and dopamine (P<0.05). Distigmine did not significantly improve CLP animal survival rate. CONCLUSIONS: The cholinesterase inhibitor distigmine inhibited induction of inflammatory cytokines and catecholamines as well as HRV suppression in a rat CLP model, suggesting that an agent modulating the cholinergic anti-inflammatory pathway can control excess cytokine production involved in the pathogenesis of severe sepsis/septic shock.

Duration of well-controlled core temperature correlates with neurological outcome in patients with post-cardiac arrest syndrome.

PURPOSE: Detailed procedures for optimal therapeutic hypothermia (TH) have yet to be established. We examined how duration of well-controlled core temperature within the first 24 hours after cardiac arrests (CA) correlated with neurological outcomes of successfully resuscitated out-of-hospital CA (OHCA) patients. METHODS: OHCA patients who survived over 24 hours and treated with TH were included. Core temperature was measured every hour. Physicians intended to maintain temperature at 33 °C ± 1 °C for 24 hours. Cerebral performance categories (CPC) of patients at 6 months were recorded and patients were retrospectively divided into favorable (CPC1,2) and poor (CPC3-5) neurological outcome groups. Total time while the core temperature reached to 33 °C ± 1 °C within the first 24 hours after CA was measured and this duration was defined that of well-controlled temperature. receiver-operating characteristic analysis was performed on duration of well-controlled temperature to select the optimal cutoff value. Neurological outcome predictors were investigated by logistic regression analysis. RESULTS: Fifty-six patients were included. Optimal cutoff value of duration of well-controlled temperature was 18 hours. Ratio of male sex, witnessed by emergency medical service (EMS) personnel, first electrocardiogram as shockable, and duration of well-controlled core temperature ≥ 18 h of favorable neurological outcome group (n = 21) were significantly larger than that of poor neurological outcome group (n = 35). Logistic regression analysis identified "witnessed by EMS", "performed bystander CPR," and "the duration ≥ 18 h" as independent predictors of favorable neurological outcome. CONCLUSION: TH maintained at target temperature of 33 °C ± 1 °C over 18 hours independently correlated with favorable neurological outcome. Therefore, stable core temperature control may improve neurological outcome of successfully resuscitated OHCA.

Belt Electrode-Skeletal Muscle Electrical Stimulation in Older Hemodialysis Patients with Reduced Physical Activity: A Randomized Controlled Pilot Study.

Background: Although patients receiving hemodialysis are more likely to develop metabolic disorders and muscle weakness at an earlier stage than healthy individuals, many older dialysis patients have difficulty establishing exercise habits to prevent these problems. Therefore, we evaluated the use of belt electrode-skeletal muscle electrical stimulation (B-SES), which can stimulate a wider area than conventional electrical muscle stimulation (EMS), to examine its application and safety in older hemodialysis patients as a means to improve lower extremity function without voluntary effort. Methods: This study was a randomized controlled trial (RCT) involving 20 older dialysis patients (>65 years old) with reduced physical activity. The control group received 12 weeks of routine care only and the intervention group received 12 weeks of B-SES during hemodialysis in addition to routine care. The primary endpoint was the 6 min walk test (6MWT) distance, while the Short Physical Performance Battery (SPPB), body composition, Functional Independence Measure (FIM), biochemistry test, and blood pressure/pulse measurements were used as secondary endpoints. Results: As a result of the 12-week B-SES intervention, no increase in creatine kinase or C-reactive protein levels was observed after the intervention in either group, and no adverse events attributed to the B-SES intervention were observed in the intervention group. Furthermore, the intervention group showed a significant improvement in the 6MWT and SPPB scores after the intervention. Conclusions: The results of this study suggest that a 12-week B-SES intervention during hemodialysis sessions safely improves 6MWT distance and SPPB scores in older patients with a reduced level of physical activity.

Comparison of interleukin-6 removal properties among hemofilters consisting of varying membrane materials and surface areas: an in vitro study.

BACKGROUND/AIMS: We sought to identify the most relevant hemofilter for cytokine removal based on the mechanisms of filtration and adsorption. METHODS: Ascites were filtered using four types of hemofilters composed of different membrane materials (polymethyl methacrylate, PMMA, cellulose triacetate, CTA, or polysulfone, PS) and different surface areas (1.0 or 2.1 m(2)) to investigate the rate of interleukin-6 (IL-6) filtration. Next, ascites were perfused through each hemofilter without obtaining a filtrate to study each filter's adsorptive capability. RESULTS: The PMMA hemofilters resulted in a marginal observed IL-6 filtration rates, whereas the CTA and PS hemofilters resulted in highly effective IL-6 filtration. Regarding the IL-6 adsorptive capabilities of the filters, the PMMA hemofilter with a large surface area showed the highest level of IL-6 clearance. CONCLUSION: The present findings suggest that when cytokine removal based on filtration is desired, CTA or PS hemofilters should be selected. When IL-6 removal based on adsorption is desired, a PMMA hemofilter with a large surface area should be selected.

Gram-negative bacteremia induces greater magnitude of inflammatory response than Gram-positive bacteremia.

INTRODUCTION: Bacteremia is recognized as a critical condition that influences the outcome of sepsis. Although large-scale surveillance studies of bacterial species causing bacteremia have been published, the pathophysiological differences in bacteremias with different causative bacterial species remain unclear. The objective of the present study is to investigate the differences in pathophysiology and the clinical course of bacteremia caused by different bacterial species. METHODS: We reviewed the medical records of all consecutive patients admitted to the general intensive care unit (ICU) of a university teaching hospital during the eight-year period since introduction of a rapid assay for interleukin (IL)-6 blood level to routine ICU practice in May 2000. White blood cell count, C-reactive protein (CRP), IL-6 blood level, and clinical course were compared among different pathogenic bacterial species. RESULTS: The 259 eligible patients, as well as 515 eligible culture-positive blood samples collected from them, were included in this study. CRP, IL-6 blood level, and mortality were significantly higher in the septic shock group (n = 57) than in the sepsis group (n = 127) (P < 0.001). The 515 eligible culture-positive blood samples harbored a total of 593 isolates of microorganisms (Gram-positive, 407; Gram-negative, 176; fungi, 10). The incidence of Gram-negative bacteremia was significantly higher in the septic shock group than in the sepsis group (P < 0.001) and in the severe sepsis group (n = 75, P < 0.01). CRP and IL-6 blood level were significantly higher in Gram-negative bacteremia (n = 176) than in Gram-positive bacteremia (n = 407) (P < 0.001, <0.0005, respectively). CONCLUSIONS: The incidence of Gram-negative bacteremia was significantly higher in bacteremic ICU patients with septic shock than in those with sepsis or severe sepsis. Furthermore, CRP and IL-6 levels were significantly higher in Gram-negative bacteremia than in Gram-positive bacteremia. These findings suggest that differences in host responses and virulence mechanisms of different pathogenic microorganisms should be considered in treatment of bacteremic patients, and that new countermeasures beyond conventional antimicrobial medications are urgently needed.

S-100B and neuron-specific enolase as predictors of neurological outcome in patients after cardiac arrest and return of spontaneous circulation: a systematic review.

INTRODUCTION: Neurological prognostic factors after cardiopulmonary resuscitation (CPR) in patients with cardiac arrest (CA) as early and accurately as possible are urgently needed to determine therapeutic strategies after successful CPR. In particular, serum levels of protein neuron-specific enolase (NSE) and S-100B are considered promising candidates for neurological predictors, and many investigations on the clinical usefulness of these markers have been published. However, the design adopted varied from study to study, making a systematic literature review extremely difficult. The present review focuses on the following three respects for the study design: definitions of outcome, value of specificity and time points of blood sampling. METHODS: A Medline search of literature published before August 2008 was performed using the following search terms: "NSE vs CA or CPR", "S100 vs CA or CPR". Publications examining the clinical usefulness of NSE or S-100B as a prognostic predictor in two outcome groups were reviewed. All publications met with inclusion criteria were classified into three groups with respect to the definitions of outcome; "dead or alive", "regained consciousness or remained comatose", and "return to independent daily life or not". The significance of differences between two outcome groups, cutoff values and predictive accuracy on each time points of blood sampling were investigated. RESULTS: A total of 54 papers were retrieved by the initial text search, and 24 were finally selected. In the three classified groups, most of the studies showed the significance of differences and concluded these biomarkers were useful for neurological predictor. However, in view of blood sampling points, the significance was not always detected. Nevertheless, only five studies involved uniform application of a blood sampling schedule with sampling intervals specified based on a set starting point. Specificity was not always set to 100%, therefore it is difficult to indiscriminately assess the cut-off values and its predictive accuracy of these biomarkers in this meta analysis. CONCLUSIONS: In such circumstances, the findings of the present study should aid future investigators in examining the clinical usefulness of these markers and determination of cut-off values.

Role of ligand-specific integrins in endothelial cell alignment and elongation induced by cyclic strain.

Ligand-specific integrins are thought to play a critical role in regulating multiple biological processes. However, the mechanisms by which ligand-specific integrins mediate external stimuli and activate intracellular signaling pathways remain to be elucidated. The aim of this study was to clarify the role of ligand-specific integrins in the morphological changes induced by cyclic strain (CS) via the p38 mitogen-activated protein kinase (p38 MAPK) pathway. Endothelial cells (ECs) were cultured on collagen (a ligand for integrin alpha 2 beta1, but not for alpha 5 and beta 4)-coated flexible plates and incubated for 24 h with or without anti-alpha2 integrin antibody (anti-alpha2), anti-alpha5, anti-beta1, or anti-beta4. ECs were then subjected to 15.6% average CS at 60 cycles/min up to 24 h. After exposure to CS, the cell shape index (defined as (4pi x cell area)/(cell perimeter)(2)), the cell orientation angle, and activation of p38 MAPK were assessed. ECs in the absence of integrin-blocking antibodies were elongated and aligned in response to CS. Anti-alpha 2 and anti-beta1 abolished both morphological changes of ECs as well as the activation of p38 MAPK. In contrast, anti-alpha 5 and anti-beta 4 inhibited neither morphological changes of ECs nor the activation of p38 MAPK. Our results indicate that ligand-specific integrins play a crucial role in the morphological changes of ECs induced by CS via the p38 MAPK pathway.

Trends in and perspectives on extracorporeal membrane oxygenation for severe adult respiratory failure.

Various approaches such as ventilator management involving lung-protective ventilation, corticosteroids, prone positioning, and nitric oxide have failed to maintain sufficient lung oxygenation or appropriate ventilation competence in very severe acute respiratory distress syndrome (ARDS). Extracorporeal membrane oxygenation (ECMO) has been aggressively introduced for such patients, although in only a few institutions. The clinical usefulness of ECMO in a large-scale multicenter study (CESAR trial, 2009) and continued development/improvement of ECMO devices have facilitated performance of ECMO, with further increase in the number of institutions adopting ECMO therapy. Clinical usefulness of ECMO was documented in many cases of severe ARDS secondary to influenza A (H1N1) 2009 infection. ECMO requires establishment of an appropriate management system to minimize fatal complications (e.g., hemorrhage), which requires a multidisciplinary team. This, in combination with a new technique, interventional lung assist, will further extend the indications for ECMO. ECMO can be expected to gain importance as a respiratory support technique.

Treatment of septic shock with continuous HDF using 2 PMMA hemofilters for enhanced intensity.

PURPOSE: Cytokines play pivotal roles in the pathophysiology of severe sepsis/septic shock, and continuous hemodiafiltration using a polymethylmethacrylate membrane hemofilter (PMMA-CHDF) removes cytokines efficiently and continuously, mainly through adsorption to a hemofilter membrane. The aim of this study was to investigate the clinical efficacy of enhanced intensity PMMA-CHDF in treating refractory septic shock. METHODS: Seventy-two septic shock patients admitted to the intensive care unit (ICU) underwent critical care including PMMA-CHDF. We employed enhanced intensity PMMA-CHDF to improve the cytokine removal rate by increasing the hemofilter membrane area in 10 refractory septic shock patients (enhanced intensity group, EI group; 2 extracorporeal CHDF circuits using the hemofilter with a larger membrane area of 2.1 m2). Other patients undergoing conventional PMMA-CHDF and matched for severity with the EI group, comprised a matched conventional group (MC group; using a PMMA membrane hemofilter with a membrane area of 1.0 m2; n=15). The case-control comparison was performed between the 2 groups. RESULTS: Enhanced intensity PMMA-CHDF significantly increased mean arterial pressure by 23.8% in 1 hour (p=0.037), decreased the blood lactate level by 28.6% in 12 hours (p=0.006), and reduced blood IL-6 level in 24 hours (p=0.005). The ICU survival rate in the EI group was significantly better than that in the MC group (60% vs. 13.3%, p=0.028). CONCLUSION: Enhanced intensity PMMA-CHDF may improve hemodynamics and survival rate in patients with refractory septic shock.

Blood ammonia and lactate levels on hospital arrival as a predictive biomarker in patients with out-of-hospital cardiac arrest.

INTRODUCTION: No reliable predictor for the prognosis of out-of-hospital cardiac arrest (OHCA) on arrival at hospital has been identified so far. We speculate that ammonia and lactate may predict patient outcome. METHODS: This is a prospective observational study. Non-traumatic OHCA patients who gained sustained return of spontaneous circulation and were admitted to acute care unit were included. Blood ammonia and lactate levels were measured on arrival at hospital. The patients were classified into two groups: 'favourable outcome' group (Cerebral Performance Category CPC1-2 at 6-months' follow-up) and 'poor outcome' group (CPC3-5). Basal characteristics obtained from the Utstein template and biomarker levels were compared between these two outcome groups. Independent predictors were selected from all candidates using logistic regression analysis. RESULTS: A total of 98 patients were included. Ammonia and lactate levels in the favourable outcome group (n=10) were significantly lower than those in poor outcome group (n=88) (p<0.05, respectively). On receiver operating characteristic analysis, the optimal cut-off value for predicting favourable outcome was determined as 170 µg dl(-1) of ammonia and 12.0 mmol l(-1) of lactate (area under the curve; 0.714 and 0.735, respectively). Logistic regression analysis identified ammonia (≤170 µg dl(-1)), therapeutic hypothermia and witnessed by emergency medical service personnel as independent predictors of favourable outcome. When both these biomarker levels were over threshold, positive predictive value (PPV) for poor outcome was calculated as 100%. CONCLUSIONS: Blood ammonia and lactate levels on arrival are independent prognostic factors for OHCA. PPV with the combination of these biomarkers predicting poor outcome is high enough to be useful in clinical settings.

Non-renal indications for continuous renal replacement therapy: current status in Japan.

Continuous renal replacement therapy (CRRT) has been extensively used in Japan as renal support for critically ill patients managed in the ICU. In Japan, active research has also been conducted on non-renal indications for CRRT, i.e. the use of CRRT for purposes other than renal support. Various methods of blood purification have been attempted to remove inflammatory mediators, such as cytokines, in patients with severe sepsis or septic shock. In these attempts, efficacy was demonstrated for continuous hemodiafiltration(CHDF) using a polymethyl methacrylate (PMMA) membrane hemofilter which is capable of adsorbing and removing various cytokines, plasma diafiltration, and online CHDF. Furthermore, a recently developed cytokine-adsorbing column is now under clinical evaluation. Definite evidence for the efficacy of CRRT for non-renal indications has not been established. In evaluating the efficacy of CRRT for non-renal indications, it is essential to focus on patients subjected to be studied, such as severe sepsis or septic shock, and to evaluate its indication, commencement, termination of therapy and also its therapeutic effects based on analysis of blood levels of the target substances to be removed (e.g. cytokines). IL-6 blood level appears to be useful as a variable for this evaluation. It is expected that evidence endorsing the validity of these methods now being attempted in Japan will be reported near future.

Differential effects of shear stress and cyclic strain on Sp1 phosphorylation by protein kinase Czeta modulates membrane type 1-matrix metalloproteinase in endothelial cells.

Membrane type 1-matrix metalloproteinase (MT1-MMP) plays a key role in extracellular matrix remodeling, endothelial cell (EC) migration, and angiogenesis. Whereas cyclic strain (CS) increases MT1-MMP expression, shear stress (SS) decreases MT1-MMP expression. The aim of this study was to determine if changes in levels of Sp1 phosphorylation induced by protein kinase Czeta (PKCzeta) in ECs exposed to SS but not CS are important for MT1-MMP expression. The results showed that SS increased Sp1 phosphorylation, which could be inhibited by pretreatment with PKCzeta inhibitors. In the presence of PKCzeta inhibitors, the SS-mediated decrease in MT1-MMP protein expression was also abolished. These data demonstrate that increased affinity of Sp1 for MT1-MMP's promoter site occurs as a consequence of PKCzeta-induced phosphorylation of Sp1 in response to SS, increasing Sp1 binding affinity for the promoter site, preventing Egr-1 binding, and consequently decreasing MT1-MMP expression.