Microvascular thrombosis and multiple organ dysfunction syndrome:

Biological basis and pathological relevance of microvascular thrombosis

Microvascular thrombosis indicates a pathological occlusion of microvessels by fibrin- and/or platelet-rich thrombi. It is observed during systemic infections, cancer, myocardial infarction, stroke, neurodegenerative diseases and in thrombotic microangiopathies. Microvessel thrombosis can cause greatly differing symptoms that range from limited changes in plasma coagulation markers to severe multi-organ failure. Because microvessel thrombi are difficult to detect and often occur only transiently, their importance for disease development and host biology is likely markedly under-appreciated. Recently, clear indications for a biological basis of microvascular thrombosis have been obtained. During systemic infections microvessel thrombosis can mediate an intravascular innate immune response (immunothrombosis). This biological form of thrombosis is based on the generation of fibrin inside blood vessels and is critically triggered by neutrophils and their interactions with platelets which result in the release of neutrophil extracellular traps (extracellular nucleosomes). Immunothrombosis is critically supported by neutrophil elastase and the activator molecules of blood coagulation tissue factor and factor XII. Identification of the biological driving forces of microvascular thrombosis should help to elucidate the mechanisms promoting pathological vessel occlusions in both microvessels and large vessels.

Biology of sepsis: its relevance to pediatric nephrology

Because of its multi-organ involvement, the syndrome of sepsis provides clinical challenges to a wide variety of health care providers. While multi-organ dysfunction triggered by sepsis requires general supportive critical care provided by intensivists, the impact of sepsis on renal function and the ability of renal replacement therapies to modulate its biologic consequences provide a significant opportunity for pediatric nephrologists and related care providers to impact outcomes. In this review, we aim to highlight newer areas of understanding of the pathobiology of sepsis with special emphasis on those aspects of particular interest to pediatric nephrology. As such, we aim to: (1) review the definition of sepsis and discuss advances in our mechanistic understanding of sepsis; (2) review current hypotheses regarding sepsis-induced acute kidney injury (AKI) and describe its epidemiology based on evolving definitions of AKI; (3) review the impact of renal failure on the immune system, highlighting the sepsis risk in this cohort and strategies that might minimize this risk; (4) review how renal replacement therapeutic strategies may impact sepsis-induced AKI outcomes. By focusing the review on these specific areas, we have omitted other important areas of the biology of sepsis and additional interactions with renal function from this discussion; however, we have aimed to provide a comprehensive list of references that provide contemporary reviews of these additional areas.

Changes in fibrinolysis and severity of organ failure in sepsis: a prospective observational study using point-of-care test--ROTEM

PURPOSE

We hypothesized that the thromboelastometry (ROTEM; Pentapharm GmbH, Munich, Germany) fibrinolysis parameter "maximum lysis" (ML) would have an independent inverse association with the severity of organ failure in sepsis.

METHODS

Selected adult patients with sepsis (n = 77) were recruited within 24 hours of antibiotic commencement. Patients with Sequential Organ Failure Assessment score higher than 1 (n = 57) were followed for 72 hours. Prothrombin fragments 1 + 2, plasminogen activator inhibitor-1 (aPAI-1), ROTEM, and routine coagulation tests were measured daily along with Sequential Organ Failure Assessment scores.

RESULTS

The activity of functional aPAI-1 increased with increasing severity of organ failure (P = .01) and was higher as compared with healthy controls (95% confidence interval, -65.4 to -29.9; P < .001). There was a decreasing trend in ML with increased organ failure (P = .001); however, there was no trend in d-dimer. Among all tests, only the lower ML (ß = -0.38, P < .001) and higher international normalized ratio (INR; ß = 0.32, P = .002) values significantly contributed to greater severity of organ failure (R(2) = 0.35, F2,73 = 19.29, P < .001). Despite an increase in INR, the prothrombin fragment remained unchanged (P = .89). Strong correlations were observed between early (24 hours) increase in fibrinolysis and recovery of organ failures for 48 hours (ML: r = 0.679, P = .001; aPAI-1: r = 0.694, P < .001).

CONCLUSIONS

Lower ML and higher INR values predicted greater severity of organ failure at presentation. Further studies are required, as ROTEM could aid selection of patients and guide interventions aimed at fibrinolysis in severe sepsis.

The matricellular "cysteine-rich protein 61" is released from activated platelets and increased in the circulation during experimentally induced sepsis

Sepsis and sepsis-induced organ dysfunction remain lethal and common conditions among intensive care patients. Accumulating evidence suggests that the matricellular Cyr61/CCN1 (cysteine-rich, angiogenic-inducer, 61) protein is involved in the regulation of inflammatory responses and possesses organ-protective capabilities in diseases of an inflammatory etiology. However, its regulation in sepsis remains largely unexplored. The present study provides a comprehensive description of CCN1 regulation in the circulation and vital organs during experimentally induced sepsis with developing organ dysfunction. Female CD-1 mice served as baseline controls or were subjected to cecal ligation and puncture (CLP) for 18 to 96 h, and CCN1 regulation was analyzed in selected organs and in the circulation. A 5-, 5-, and 3-fold increases in circulating CCN1 protein were observed at 18, 48, and 96 h after CLP, respectively. Hepatic and pulmonary CCN1 mRNA expression was down-regulated by 80%, 60%, and 55% and 85%, 80%, and 65% at 18, 48, and 96 h after CLP and undetectable in circulating white blood cells. To identify a potential source for the circulating protein, mouse and human platelets were explored and revealed to contain CCN1. Human platelets were stimulated by thrombin and a specific PAR1 agonist (SFLLRN) in vitro. Both agonists induced an instant CCN1 release, and the effect of SFLLRN was blocked by the specific antagonist RWJ56110. The current study demonstrates that experimental sepsis is associated with a robust increase in circulating CCN1 protein levels and a paradoxical downregulation of CCN1 mRNA expression in vital organs. It provides evidence that CCN1 is released from activated platelets, suggesting that platelets constitute a novel source for CCN1 release to the circulation during sepsis.

Urokinase-type plasminogen activator receptor as a predictor of poor outcome in patients with systemic inflammatory response syndrome

BACKGROUND

Urokinase-type plasminogen activator (uPA) and urokinase-type plasminogen activator receptor (uPAR) are known as important factors, which mediate a variety of functions in terms of vascular homeostasis, inflammation and tissue repair. However, their role in systemic inflammatory response syndrome (SIRS) has been less well studied. This study aimed to test the hypothesis that the abnormalities of fibrinolysis and degradation of extracellular matrix mediated by uPA and uPAR are directly related to the patients with SIRS. We therefore analyzed their role and clinicopathological significance in patients with SIRS.

METHODS

A case-control study was conducted with 85 patients who were divided into two groups according to the diagnostic criteria of SIRS: SIRS group (n=50) and non-SIRS group (n=35). The SIRS group was divided into MODS group (n=26) and non-MODS group (n=24) by their severity, and survival group (n=35) and non-survival group (n=15) by their prognosis. Another 30 healthy adults served as normal controls. uPA and uPAR in plasma were detected by commercial enzyme-linked immunosorbent assay (ELISA) kits.

RESULTS

The plasma level of uPA was lower in the SIRS group than in the non-SIRS group and controls (P<0.001 and P<0.001). It was lower in sepsis patients and the MODS group than in the non-sepsis patients and the non-MODS patients (all P<0.05). However, there was no difference in uPA level between survivors and non-survivors (P>0.05). The plasma level of uPAR increased in the SIRS group compared with the non-SIRS group and controls (P<0.001 and P<0.001). There was a significant elevation of uPAR in sepsis patients, MODS patients and non-survivors as compared with non-sepsis patients, non-MODS patients and survivors respectively (all P<0.05). Plasma uPAR levels were positively correlated with APACHE II score (r=0.575, P<0.001) and SOFA score (r=0.349, P=0.013). AUCs for the prediction of SIRS mortality were 0.67 and 0.51, respectively, for uPA and uPAR.

CONCLUSION

uPAR could be a predictor of poor outcome in patients with SIRS.

Histone deacetylase inhibitor treatment attenuates coagulation imbalance in a lethal murine model of sepsis

BACKGROUND

Sepsis has a profound impact on the inflammatory and hemostatic systems. In addition to systemic inflammation, it can produce disseminated intravascular coagulation, microvascular thrombosis, consumptive coagulopathy, and multiple organ failure. We have shown that treatment with suberoylanilide hydroxamic acid (SAHA), a histone deacetylase inhibitor (HDACI), improves survival in a lethal model of cecal ligation and puncture (CLP) in mice, but its effect on coagulation remains unknown. The goal of this study was to quantify the impact of SAHA treatment on coagulopathy in sepsis.

METHODS

C57BL/6J mice were subjected to CLP, and 1 hour later given intraperitoneally either SAHA dissolved in dimethyl sulfoxide (DMSO) or DMSO only. Sham-operated animals were handled in similar manner without CLP. Blood samples were collected by cardiac puncture and evaluated using the TEG 5000 Thrombelastograph Hemostasis Analyzer System.

RESULTS

Compared with the sham group, all animals in DMSO vehicle group died within 72 hours, and developed coagulopathy that manifested as prolonged initial fibrin formation and fibrin cross-linkage time, and decreased clot formation speed, platelet function, and clot rigidity. SAHA treatment significantly improved survival and was associated with improvement in fibrin cross-linkage and clot formation, as well as platelet function and clot rigidity, without a significant impact on the clot initiation parameters.

CONCLUSION

SAHA treatment enhances survival and attenuates sepsis-associated coagulopathy by improving fibrin cross-linkage, rate of clot formation, platelet function, and clot strength. HDACI may represent a novel therapeutic strategy for correcting sepsis-associated coagulopathy.

Classifying types of disseminated intravascular coagulation: clinical and animal models

Disseminated intravascular coagulation (DIC) has a common pathogenesis in terms of persistent widespread activation of coagulation in the presence of underlying disease, but the degree of fibrinolytic activation often differs by DIC type. DIC with suppressed fibrinolysis is a DIC type usually seen in sepsis. Coagulation activation is severe, but fibrinolytic activation is mild. DIC with enhanced fibrinolysis is a DIC type usually seen in acute promyelocytic leukemia (APL). Both coagulation activation and fibrinolytic activation are severe. DIC with balanced fibrinolysis is a DIC type usually seen in solid tumors, with an intermediate pathogenesis between the above two types. In animal DIC models, lipopolysaccharide (LPS)-induced models are similar to suppressed-fibrinolytic-type DIC, whereas tissue factor (TF)-induced models are similar to enhanced fibrinolytic/balanced fibrinolytic DIC. Appropriate diagnosis and treatment may also differ depending on the DIC type.

Microvascular platforms for the study of platelet-vessel wall interactions

Platelets interact with the endothelium to regulate vascular integrity and barrier function, mediate inflammation and immune response, and prevent and arrest hemorrhage. In this review, we describe existing tools to study the flow-dependent interactions of platelets with the vessel wall. We also discuss our work on building engineered microvessels to study the roles of platelets on endothelial barrier function, endothelial sprouting, and thrombus formation on both quiescent and stimulated endothelium. In particular, we will show the advantage of using a cell-remodelable system in the studies of platelet-vessel wall interactions.

Increased prothrombotic property as a risk factor of acute kidney injury after surgical repair of abdominal aortic aneurysm: a prospective observational study

Background

Acute kidney injury (AKI) is one of the major morbidities after surgical repair of abdominal aortic aneurysm (AAA); however, precise pathogenesis of this morbidity has not been well determined. Since prothrombotic coagulation abnormality may precede organ dysfunction in systemic inflammatory state, we examined the kinetics of von Willebrand factor (VWF) and a disintegrin-like metalloprotease with thrombospondin type 1 motif 13 (ADAMTS13), a cleaving enzyme of VWF, on the development of AKI after AAA surgery.

Methods

The kinetics of ADAMTS13 and VWF were examined in ten patients who underwent surgical repair of AAA. The changes in plasma neutrophil gelatinase-associated lipocalin (NGAL), a novel biomarker for AKI, and serum creatinine concentration were also examined at four points until seventh postoperative day (POD). Clinical diagnosis of AKI was based on the change in serum creatinine concentration and urine output according to Acute Kidney Injury Network (AKIN) criteria.

Results

ADAMTS13 activity was significantly lower than normal level before the surgery and showed a trend of decrease toward 3POD. The VWF/ADAMTS13 ratio showed a significant increase on 1POD, which persisted until 7POD. None of patents was diagnosed as AKI based on AKIN criteria, although two patients received furosemide and/or carperitide therapy because of decreased urine output less than 0.5 ml/kg/h for several hours in ICU. Plasma NGAL showed a trend to increase after the surgery, which was significant on 3POD. The change in plasma NGAL was significantly correlated with VWF/ADAMTS13 ratio (P < 0.01).

Conclusions

This study has shown that patients undergoing AAA surgery were prothrombotic after the surgery because of high VWF/ADAMTS13 ratio. Correlation between VWF/ADAMTS13 ratio and NGAL might indicate contribution of thrombotic event to subclinical AKI in the patients undergoing AAA surgery.

Effect of Red Blood Cells on Platelet Activation and Thrombus Formation in Tortuous Arterioles

Thrombosis is a major contributor to cardiovascular disease, which can lead to myocardial infarction and stroke. Thrombosis may form in tortuous microvessels, which are often seen throughout the human body, but the microscale mechanisms and processes are not well understood. In straight vessels, the presence of red blood cells (RBCs) is known to push platelets toward walls, which may affect platelet aggregation and thrombus formation. However in tortuous vessels, the effects of RBC interactions with platelets in thrombosis are largely unknown. Accordingly, the objective of this work was to determine the physical effects of RBCs, platelet size, and vessel tortuosity on platelet activation and thrombus formation in tortuous arterioles. A discrete element computational model was used to simulate the transport, collision, adhesion, aggregation, and shear-induced platelet activation of hundreds of individual platelets and RBCs in thrombus formation in tortuous arterioles. Results showed that high shear stress near the inner sides of curved arteriole walls activated platelets to initiate thrombosis. RBCs initially promoted platelet activation, but then collisions of RBCs with mural thrombi reduced the amount of mural thrombus and the size of emboli. In the absence of RBCs, mural thrombus mass was smaller in a highly tortuous arteriole compared to a less tortuous arteriole. In the presence of RBCs however, mural thrombus mass was larger in the highly tortuous arteriole compared to the less tortuous arteriole. As well, smaller platelet size yielded less mural thrombus mass and smaller emboli, either with or without RBCs. This study shed light on microscopic interactions of RBCs and platelets in tortuous microvessels, which have implications in various pathologies associated with thrombosis and bleeding.

The prognostic value of ADAMTS13 (a disintegrin and metalloprotease with thrombospondin type 1 repeats, member 13) deficiency in septic shock patients involves interleukin-6 and is not dependent on disseminated intravascular coagulation

Introduction

ADAMTS13 (a disintegrin and metalloprotease with thrombospondin type 1 repeats, member 13) deficiency has been reported in patients with sepsis but its clinical relevance and pathophysiology remain unclear. Our objectives were to assess the clinical significance, prognostic value and pathophysiology of ADAMTS13 deficiency in patients with septic shock with and without disseminated intravascular coagulation (DIC).

Methods

This was a prospective monocenter cohort study of patients with septic shock. Von Willebrand Factor, ADAMTS13-related parameters and plasma IL-6 concentration were measured at inclusion to the study. Patients were categorized into three groups according to the presence of ADAMT13 deficiency (<30%) or DIC.

Results

This study included 72 patients with a median age of 59 years (interquartile range (IQR) 50 to 71). Each of the included patients received vasopressors; 55 (76%) were under mechanical ventilation and 22 (33%) underwent renal replacement therapy. Overall, 19 patients (26%) had DIC, and 36 patients had ADMTS13 deficiency (50%). Patients with DIC, ADAMTS13 deficiency or both were more severe at ICU admission. Mortality was higher in septic shock patients from group one. By multivariate analysis, Simplified Acute Physiology Score 2 (SAPS2) score (odds ratio (OR) 1.11/point; 95% CI 1.01 to 1.24) and ADAMTS13 activity <30% (OR 11.86; 95% CI 1.36 to 103.52) were independently associated with hospital mortality. There was no correlation between ADAMTS13 activity and the International Society for Thrombosis and Haemostasis (ISTH) score (r_{s =} -0.97, P = 0.41) suggesting that ADAMTS13 functional deficiency and DIC were independent parameters. IL-6 level was higher in patients with ADAMTS13 activity <30% [895 (IQR 330 to 1843) pg/mL versus 83 (IQR 43 to 118), P = 0.0003).

Conclusions

Septic shock was associated with a functional deficiency of ADAMTS13, independently of DIC. ADAMTS13 functional deficiency is then a prognostic factor for mortality in septic shock patients, independently of DIC.

Predictors of Disseminated Intravascular Coagulation in Patients with Septic Shock

Purpose. The goal of this study was to identify potential clinical predictors for the development of disseminated intravascular coagulation (DIC) in patients with septic shock. Material and Methods. We performed a retrospective analysis of a cohort of adult (>18 years of age) patients with septic shock admitted to a medical ICU in a tertiary care hospital from July 2005 until September 2007. A multivariate logistic regression model was used to determine the association of risk factors with overt DIC. Results. In this study, a total of 390 patients with septic shock were analyzed, of whom 66 (17%) developed overt DIC. Hospital mortality was significantly greater in patients who developed overt DIC (68% versus 38%, P<0.001). A delay in the timing of antibiotics was associated with an increased risk of the development of overt DIC (P<0.001). Patients on antiplatelet therapy prior to hospital admission and who that received adequate early goal-directed therapy (EGDT) were associated with a decreased risk of overt DIC (P<0.001). Conclusions. In our cohort of patients with septic shock, there was a risk reduction for overt DIC in patients on antiplatelet therapy and adequate EGDT, while there was an increased risk of DIC with antibiotic delay.

The dynamics of angiogenic factors and their soluble receptors in relation to organ dysfunction in disseminated intravascular coagulation associated with sepsis

We prospectively studied (1) the relationships between angiogenic factors, their soluble receptors and organ dysfunction and (2) the effects of disseminated intravascular coagulation (DIC)-induced platelet consumption, thrombin generation, and tissue hypoxia on the expression of the factors and receptors. Fifty patients with sepsis were classified into two subgroups: 37 patients with DIC and 13 patients without DIC. DIC patients showed higher Sequential Organ Failure Assessment (SOFA) scores, the prevalence of multiple organ dysfunction syndrome (MODS) and more increased soluble fibrin and lactate levels. We observed lower levels of vascular endothelial growth factor (VEGF), soluble VEGF receptor 2 (sVEGFR2), angiopoietin 1 (Ang1) and Ang1/Ang2, and higher sVEGFR1 and Ang2 levels in DIC patients, but not significant differences in soluble Tie2 expression during the study period. The levels of VEGF, sVEGFR1, and Ang2 in DIC patients correlated with the SOFA scores. Clear differences were observed in the levels of Ang2 in the DIC patients between survivors and nonsurvivors and between those with and without MODS. The area under receiver operating characteristic curves for predicting death and MODS by Ang2 were 0.710 and 0.784, respectively. The VEGF levels showed a marked correlation with the platelet counts. Soluble fibrin and lactate levels independently predicted increases in the levels of VEGF, sVEGFR1, and Ang2 in DIC patients. In conclusion, VEGF, sVEGFR1, Ang2, and Ang1/Ang2, especially Ang2, may have roles in the development of MODS in sepsis associated with DIC, and VEGF, sVEGFR1, and Ang2 serum levels correlated with the extent of DIC-induced platelet consumption, thrombin generation, and blood lactate levels.

Microparticles are new biomarkers of septic shock-induced disseminated intravascular coagulopathy

PURPOSE

Septic shock-induced disseminated intravascular coagulopathy (DIC) contributes to multiple organ failure. Mechanisms governing vascular responses to open occurrence of DIC have not yet been established. Circulating plasma microparticles (MPs), released upon cell stress, constitute a catalytic procoagulant surface and are surrogates of vascular cell activation/injury. Herein, MPs were assessed as possible markers of haemostatic and vascular dysfunction in the DIC time course.

METHODS

One hundred patients with septic shock from three ICUs were enrolled and their haemostatic status evaluated at admission (D1), D2, D3 and D7. Circulating procoagulant MPs were isolated, quantified by prothrombinase assay and their cellular origin determined. DIC diagnosis was made according to the JAAM 2006 score.

RESULTS

Ninety-two patients were analysed and 40 had DIC during the first 24 h. Routine clotting times and factor/inhibitor activity did not allow assessing vascular cell involvement. At admission, thrombin generation and fibrinolysis were observed in both groups while impaired fibrin polymerisation was evidenced only in DIC patients. Sustained thrombin generation persisted over time in both groups at D7. While total microparticle concentrations were in the same range regardless of DIC diagnosis, specific phenotypes were already detected at admission in DIC patients. Endothelial- and leucocyte-derived MPs were higher in DIC while an increased soluble glycoprotein V/platelet ratio was delayed, underscoring the first involvement of endothelial cells and leucocytes whereas platelet activation was delayed. Endothelium-derived CD105-MPs (OR 6.55) and CD31-MPs (OR 0.49) were strongly associated with early DIC in multivariate analysis.

CONCLUSION

Endothelial-derived microparticles are relevant biomarkers of septic shock-induced DIC and could be used to evaluate early vascular injury.

A multicenter, prospective validation study of the Japanese Association for Acute Medicine disseminated intravascular coagulation scoring system in patients with severe sepsis

Introduction

To validate the Japanese Association for Acute Medicine (JAAM) disseminated intravascular coagulation (DIC) scoring system in patients with severe sepsis, we conducted a multicenter, prospective study at 15 critical care centers in tertiary care hospitals.

Methods

This study included 624 severe sepsis patients. JAAM DIC was scored on the day of diagnosis of severe sepsis (day 1) and day 4. Scores for disease severity and organ dysfunction were also evaluated.

Results

The prevalence of JAAM DIC was 46.8% (292/624), and 21% of the DIC patients were scored according to the reduction rate of platelets. The JAAM DIC patients were more seriously ill and exhibited more severe systemic inflammation, a higher prevalence of multiple organ dysfunction syndrome (MODS) and worse outcomes than the non-DIC patients. Disease severity, systemic inflammation, MODS and the mortality rate worsened in accordance with an increased JAAM DIC score on day 1. The Kaplan-Meier curves demonstrated lower 1-year survival in the JAAM DIC patients than in those without DIC (log-rank test P <0.001). The JAAM DIC score on day 1 (odds ratio = 1.282, P <0.001) and the Delta JAAM DIC score (odds ratio = 0.770, P <0.001) were independent predictors of 28-day death. Dynamic changes in the JAAM DIC score from days 1 to 4 also affected prognoses. The JAAM DIC scoring system included all patients who met the International Society on Thrombosis and Haemostasis overt DIC criteria on day 1. The International Society on Thrombosis and Haemostasis scoring system missed a large number of nonsurvivors recognized by the JAAM scoring system.

Conclusions

The JAAM DIC scoring system exhibits good prognostic value in predicting MODS and poor prognosis in patients with severe sepsis and can detect more patients requiring treatment. Conducting repeated daily JAAM scoring increases the ability to predict the patient's prognosis.

Coagulofibrinolytic changes in patients with disseminated intravascular coagulation associated with post-cardiac arrest syndrome--fibrinolytic shutdown and insufficient activation of fibrinolysis lead to organ dysfunction

INTRODUCTION

Post-cardiac arrest syndrome (PCAS) is often associated with disseminated intravascular coagulation (DIC), thus leading to the development of multiple organ dysfunction syndrome (MODS). The aim of this study was to examine the pathophysiological relationships between coagulation, fibrinolysis and fibrinolytic shutdown by evaluating the levels of coagulofibrinolytic markers, including soluble fibrin, thrombin-activatable fibrinolysis inhibitor (TAFI), tissue plasminogen activator-plasminogen activator inhibitor-1 complex (tPAIC), plasmin-alpha2 plasmin inhibitor complex (PPIC), neutrophil elastase and fibrin degradation product by neutrophil elastase (EXDP).

MATERIALS AND METHODS

Fifty-two resuscitated patients were divided into two groups: 22 DIC and 30 non-DIC patients.

RESULTS

The levels of soluble fibrin, PPIC, tPAIC, EXDP and neutrophil elastase in the DIC patients with PCAS were significantly higher than those observed in the non-DIC patients. The values of the tPAIC and JAAM DIC scores were found to be independent predictors of increased SOFA scores in the DIC patients. The MODS patients demonstrated significantly higher levels of soluble fibrin and tPAIC; however, the levels of TAFI and EXDP were identical between the patients with and without MODS. In addition, positive correlations were observed between the levels of tPAIC and EXDP in the patients with non-MODS; however, no correlations were observed between these markers in the MODS patients.

CONCLUSIONS

Thrombin activation and fibrinolytic shutdown play important roles in the development of organ dysfunction in PCAS patients. Neutrophil elastase-mediated fibrinolysis cannot overcome the fibrinolytic shutdown that occurs in DIC patients with PCAS, thus resulting in the development of MODS.

Low hemorrhage-related mortality in trauma patients in a Level I trauma center employing transfusion packages and early thromboelastography-directed hemostatic resuscitation with plasma and platelets

BACKGROUND

Hemorrhage accounts for most preventable trauma deaths, but still the optimal strategy for hemostatic resuscitation remains debated.

STUDY DESIGN AND METHODS

This was a prospective study of adult trauma patients admitted to a Level I trauma center. Demography, Injury Severity Score (ISS), transfusion therapy, and mortality were registered. Hemostatic resuscitation was based on a massive transfusion protocol encompassing transfusion packages and thromboelastography (TEG)-guided therapy.

RESULTS

A total of 182 patients were included (75% males, median age 43 years, ISS of 17, 92% with blunt trauma). Overall 28-day mortality was 12% with causes of death being exsanguinations (14%), traumatic brain injury (72%, two-thirds expiring within 24 hr), and other (14%). One-fourth, 16 and 15% of the patients, received red blood cells (RBCs), plasma, or platelets (PLTs) within 2 hours from admission and 68, 71, and 75%, respectively, of patients transfused within 24 hours received the respective blood products within the first 2 hours. In patients transfused within 24 hours, the median number of blood products at 2 hours was 5 units of RBCs, 5 units of plasma, and 2 units of PLT concentrates. Nonsurvivors had lower clot strength by kaolin-activated TEG and TEG functional fibrinogen and lower kaolin-tissue factor-activated TEG α-angle and lysis after 30 minutes compared to survivors. None of the TEG variables were independent predictors of massive transfusion or mortality.

CONCLUSION

Three-fourths of the patients transfused with plasma or PLTs within 24 hours received these in the first 2 hours. Hemorrhage caused 14% of the deaths. We introduced transfusion packages and early TEG-directed hemostatic resuscitation at our hospital 10 years ago and this may have contributed to reducing hemorrhagic trauma deaths.

The CXCR1/2 ligand NAP-2 promotes directed intravascular leukocyte migration through platelet thrombi

Thrombosis promotes leukocyte infiltration into inflamed tissues, leading to organ injury in a broad range of diseases; however, the mechanisms by which thrombi guide leukocytes to sites of vascular injury remain ill-defined. Using mouse models of endothelial injury (traumatic or ischemia reperfusion), we demonstrate a distinct process of leukocyte recruitment, termed "directed intravascular migration," specifically mediated by platelet thrombi. Single adherent platelets and platelet aggregates stimulated leukocyte shape change at sites of endothelial injury; however, only thrombi were capable of inducing directed intravascular leukocyte migration. Leukocyte recruitment and migration induced by platelet thrombi occurred most prominently in veins but could also occur in arteries following ischemia-reperfusion injury. In vitro studies demonstrated a major role for platelet-derived NAP-2 (CXCL-7) and its CXCR1/2 receptor in regulating leukocyte polarization and motility. In vivo studies demonstrated the presence of an NAP-2 chemotactic gradient within the thrombus body. Pharmacologic blockade of CXCR1/2 as well as genetic deletion of NAP-2 markedly reduced leukocyte shape change and intrathrombus migration. These studies define a distinct process of leukocyte migration that is initiated by homotypic adhesive interactions between platelets, leading to the development of an NAP-2 chemotactic gradient within the thrombus body that guides leukocytes to sites of vascular injury.

Outcomes of severe sepsis and septic shock patients on chronic antiplatelet treatment: a historical cohort study

Background. Sepsis is characterized by dysfunctional activation of platelets, and antiplatelet therapy could improve the outcomes of septic patients. Methods. We performed a retrospective cohort study of severe sepsis or septic shock adult patients. Outcomes of patients on antiplatelet therapy were compared to those that were not taking antiplatelet therapy by univariate analysis followed by a propensity score analysis based on the probability of receiving antiplatelet therapy. Results. Of 651 patients included in the study 272 (42.8%) were on antiplatelet therapy before the development of severe sepsis or septic shock. After adjusting for important confounding variables antiplatelet therapy was not associated with a decreased risk of hospital mortality (odds ratio 0.73, 95% confidence interval 0.46–1.16). Antiplatelet therapy was associated with a decreased incidence of acute respiratory distress syndrome/acute lung injury (odds ratio 0.50, 95% confidence interval 0.35–0.71) and reduced need of mechanical ventilation (odds ratio 0.62, 95% confidence interval 0.45–87). Incidence of acute kidney injury was similar between both groups (odds ratio 1.08, 95% confidence interval 0.73–1.59). Conclusions. The use of antiplatelet therapy before the diagnosis of severe sepsis or septic shock was not associated with decreased hospital mortality. Antiplatelet therapy was associated with a decreased incidence of acute lung injury/acute respiratory distress syndrome.

Renal complications of seasonal and pandemic influenza A virus infections

Renal complications of influenza A virus infections are uncommon but can contribute to a deterioration in the patient's condition, which include acute kidney injury (AKI) in critically ill patients, rhabdomyolysis, hemolytic uremic syndrome (HUS), acute glomerulonephritis (AGN), disseminated intravascular coagulation (DIC), Goodpasture's syndrome, and acute tubulointerstitial nephritis (TIN). The clinical characteristics of AKI in critically ill patients with pandemic influenza A(H1N1) 2009 virus (A(H1N1)pdm09) infection are similar to uninfected patients. Underlying conditions associated with AKI include older age, diabetes mellitus, obesity, pregnancy, history of asthma, and chronic kidney disease. Histologic examination of the kidneys from patients with A(H1N1)pdm09 infection who died include acute tubular necrosis (ATN), myoglobin pigment, and DIC. A(H1N1)pdm09 is present in the kidneys of some patients. The clinical characteristics of patients with rhabdomyolysis associated with influenza A include younger age and the frequent occurrence of muscle symptoms. AKI occurs in approximately one third of patients with rhabdomyolysis due to influenza A. HUS is associated with A(H1N1)pdm09 as follows: Streptococcus pneumoniae-associated HUS following A(H1N1)pdm09 infection, HUS triggered by A(H1N1)pdm09 in patients with genetic complement dysregulation, and HUS associated with A(H1N1)pdm09 without known underlying disorder. AGN, Goodpasture's syndrome, and acute TIN are extremely rare complications of influenza A virus infection. Although the pathogenesis underlying renal injuries due to influenza A virus has not been delineated, some hypotheses have been advanced, including ATN due to renal hypoperfusion or rhabdomyolysis, glomerular microthrombosis due to DIC, direct viral injury to the kidney, and an altered immune system with systemic mononuclear cell activation following influenza A virus infections.

Using angiogenic factors and their soluble receptors to predict organ dysfunction in patients with disseminated intravascular coagulation associated with severe trauma

Introduction

Disseminated intravascular coagulation (DIC) is characterized by the concomitant activation of coagulofibrinolytic disorders and systemic inflammation associated with endothelial dysfunction-induced microvascular permeability. Angiogenic factors, including vascular endothelial growth factor (VEGF), angiopoietin (Ang), and their receptors, play crucial roles in angiogenesis and microvascular permeability. The aim of the study was to assess the relationship between angiogenic factors, their soluble receptors and organ dysfunction associated with DIC after severe trauma.

Materials and methods

A total of 57 patients with severe trauma were divided into two subgroups; 30 DIC patients and 27 non-DIC patients. The DIC was diagnosed based on the Japanese Association for Acute Medicine (JAAM) DIC and the International Society on Thrombosis and Haemostasis (ISTH) overt DIC criteria. The serum levels of angiogenic factors were measured at the time of admission (Day 1), Day 3 and Day 5. This study compared levels of these angiogenic factors between the two DIC groups, and evaluated their predictive value for organ dysfunction.

Results

DIC patients, especially those with ISTH DIC, showed higher Sequential Organ Failure Assessment (SOFA) scores and lactate levels. There were lower levels of VEGF, Ang1 and the soluble Tie2 in the ISTH DIC patients than the non-DIC patients. The levels of soluble VEGF receptor-1 (sVEGFR1), Ang2 and the Ang2/Ang1 ratio in the ISTH DIC patients were higher than in non-DIC patients. The relationship between the presence of massive transfusion and angiogenic factors indicated the same results. The levels of sVEGFR1, Ang2 and the Ang2/Ang1 ratio correlated with the SOFA scores. In particular, sVEGFR1 and Ang2 were independent predictors of an increase in the SOFA score. The lactate levels independently predicted increases in the levels of sVEGFR1 and Ang2. The decrease in the platelet counts also independently predicted the increase in Ang2 levels in DIC patients.

Conclusions

Angiogenic factors and their soluble receptors, particularly sVEGFR1 and Ang2, are considered to play pivotal roles in the development of organ dysfunction in DIC associated with severe trauma. DIC-induced tissue hypoxia and platelet consumption may play crucial roles in inducing sVEGFR1 and Ang2, and in determining the prognosis of the severity of organ dysfunction.

The utility of a diagnostic scoring system for disseminated intravascular coagulation

Disseminated intravascular coagulation (DIC) is an acquired syndrome characterized by microvascular thrombosis resulting from systemic activation of coagulation, and it should be diagnosed and treated as early as possible. No single test is sufficiently accurate to establish or rule out a diagnosis of DIC. Therefore, diagnostic scoring uses a combination of several laboratory tests. Three diagnostic scoring systems are now available and validated. Because it is not easy to assess the superiority or inferiority of these scoring systems, it may be better to select the scoring system depending on the need for an early or affirmative diagnosis of DIC.

The role of the E2F1 transcription factor in the innate immune response to systemic LPS

Previous publications from our and other groups identified E2F1 as a transcription factor involved in the regulation of inflammatory response to Toll-like receptor ligands including LPS. In this study, we challenged E2F1-deficient mice with LPS systemically and demonstrated decreased survival despite attenuated inflammatory response compared with controls. Gene expression profiling of liver tissue identified a dampened transcriptional response in the coagulation cascade in B6;129(E2F1-/-) compared with B6x129 F2 mice. These data were further corroborated by increased prothrombin time, activated partial thromboplastin time, and fibrin split products in the blood of E2F1-deficient mice, suggesting disseminated intravascular coagulation as a consequence of uncontrolled sepsis providing at least a partial explanation for their decreased survival despite attenuated inflammatory response. To identify novel miRNAs involved in the innate immune response to LPS, we also performed miRNA profiling of liver tissue from B6;129(E2F1-/-) and B6x129 F2 mice treated with LPS systemically. Our analysis identified a set of miRNAs and their mRNA targets that are significantly differentially regulated in E2F1-deficient but not control mice including let-7g, miR-101b, miR-181b, and miR-455. These miRNAs represent novel regulators of the innate immune response. In summary, we used transcriptional and miRNA profiling to characterize the response of E2F1-deficient mice to systemic LPS.

Septic shock and chemotherapy-induced cytopenia: effects on microcirculation

PURPOSE

Neutrophil and platelet activation and their interactions with endothelial cells are considered central features of sepsis-induced microcirculatory alterations. However, no study has evaluated the microvascular pattern of septic shock patients with chemotherapy-induced severe cytopenia.

METHODS

Demographic and hemodynamic variables together with sublingual microcirculation recording [orthogonal polarization spectral imaging enhanced by sidestream dark-field technology (OPS-SDF) videomicroscopy] were collected in four groups of subjects: septic shock (SS, N = 9), septic shock in cytopenic patients (NSS, N = 8), cytopenia without infection (NEUTR, N = 7), and healthy controls (CTRL, N = 13). Except for controls, all measurements were repeated after complete resolution of septic shock and/or neutropenia. Video files were processed using appropriate software tool and semiquantitatively evaluated [total vascular density (TVD, mm/mm(2)), perfused vessel density (PVD, mm/mm(2)), proportion of perfused vessels (PPV, %), mean flow index (MFI), and flow heterogeneity index (FHI)].

RESULTS

Compared with controls, there were statistically significant microcirculatory alterations within all tested groups of patients (TVD: SS = 8.8, NSS = 8.8, NEUTR = 9.1 versus CTRL = 12.6, p < 0.001; PVD: SS = 6.3, NSS = 6.1, NEUTR = 6.9 versus CTRL = 12.5, p < 0.001; PPV: SS = 71.6, NSS = 68.9, NEUTR = 73.3 versus CTRL = 98.7, p < 0.001; MFI: SS = 2.1, NSS = 1.9, NEUTR = 2.1 versus CTRL = 3.0, p < 0.05; FHI: SS = 1.0, NSS = 0.9, NEUTR = 0.6 versus CTRL = 0.0, p < 0.001). No significant differences were detected between SS, NSS, and NEUTR groups at baseline. Incomplete restoration of microcirculatory perfusion was observed after septic shock and/or neutropenia resolution with a trend towards better recovery in MFI and FHI variables in NSS as compared with SS patients.

CONCLUSIONS

Microvascular derangements in septic shock did not differ between noncytopenic and cytopenic patients. Our data might suggest that profound neutropenia and thrombocytopenia do not render microcirculation more resistant to sepsis-induced microvascular alterations. The role and mechanisms of microvascular alterations associated with chemotherapy-induced cytopenia warrant further investigation.

4G/5G Polymorphism of the plasminogen activator inhibitor-1 gene is associated with multiple organ dysfunction in critically ill patients

OBJECTIVE

Impaired fibrinolysis is associated with a higher incidence of both multiple organ dysfunction and mortality in the intensive care unit (ICU). Plasminogen activator inhibitor (PAI)-1 is the chief inhibitor of fibrinolysis. We investigated the influence of the 4G/5G polymorphism (rs1799768) of the PAI-1 gene on the plasma PAI-1 level and the outcome of critically ill patients.

METHODS

In 41 consecutive patients admitted to the ICU, PAI-1 gene polymorphism was assessed, plasma PAI-1 and arterial lactate concentrations were measured and clinical severity scores were recorded.

RESULTS

Homozygotes for the 4G allele had higher plasma levels of PAI-1 antigen. The mean ± SD PAI-1 antigen level was 193.31 ± 167.93 ng/ml for the 4G/4G genotype, 100.67 ± 114.16 ng/ml for the 4G/5G genotype and 0.43 ± 0.53 ng/ml for the 5G/5G genotype. There was a significant correlation between plasma PAI-1 and arterial lactate concentrations, as well as between PAI-1 and severity scores. The mortality rate was 63, 33 and 0% for patients with the 4G/4G, 4G/5G and 5G/5G genotypes, respectively.

CONCLUSIONS

These results demonstrate that the 4G/5G polymorphism of the PAI-1 gene affects the plasma PAI-1 concentration, which could impair fibrinolysis and cause organ failure, and thus the presence of the 4G allele increases the risk of death.

Physiopathology of shock

Shock syndromes are of three types: cardiogenic, hemorrhagic and inflammatory. Hemorrhagic shock has its initial deranged macro-hemodynamic variables in the blood volume and venous return. In cardiogenic shock there is a primary pump failure that has cardiac output/mean arterial pressure as initial deranged variables. In Inflammatory Shock it is the microcirculation that is mainly affected, while the initial deranged macrocirculation variable is the total peripheral resistance hit by systemic inflammatory response.

Treatment with unfractionated heparin attenuates coagulation and inflammation in endotoxemic mice

INTRODUCTION

In the pathogenesis of sepsis, inflammation and coagulation play a pivotal role. In addition to the anticoagulant activity, unfractionated heparin (UFH) has important immunomodulatory properties. However, different studies have reported conflicting effects on sepsis in association with heparin. The objective of this study is to determine whether UFH is able to reduce endotoxin-induced inflammation and coagulation in mice or produce improved outcome.

METHODS

C57BL/6J mice were randomly divided into two groups. Experimental mice were given intravenous injection of 8 units/20 g body weight UFH (heparin sodium) diluted in 20 μl sterile saline while the control mice received vehicle sterile saline only. They were injected with LPS (30 mg/kg, i.p.) 0.5h later. Blood was collected and Livers were harvested at 3 and 6h for analysis. In survival studies, a separate group of mice were treated with 8 units/20 g UFH (n=20) or sterile saline (n=20) given intravenously at 1, 12, 24 and 36 hours after LPS injection. Mice were monitored every 12 hours for a maximum of 72 hrs.

RESULTS

1) Pretreatment of mice with UFH strongly reduced the levels of TNF-α, IL-1β and TAT in plasma at 3 and 6h; 2) Pretreatment of mice with UFH inhibited the expression of TNF-α, IL-1β and tissue factor genes in blood cells at 3h; 3) UFH pretreatment dramatically diminished LPS-induced neutrophil sequestration (at 3 and 6h) , thrombi formation and fibrin(ogen) deposition in the liver (at 6h). 4) The UFH-pretreated group exhibited significantly lower levels of ALT and CRE at 6h. 5) Treatment with UFH could prevent mortality associated with endotoxin challenge.

CONCLUSION

These data suggest that UFH attenuates inflammation and coagulation and prevents lethality in endotoxemic mice.

Adenosine diphosphate receptor antagonist clopidogrel sulfate attenuates LPS-induced systemic inflammation in a rat model

Septic shock is characterized by systemic inflammation and can lead to hemorrhage and necrosis in multiple organs. Septic shock is one of the leading causes of death. Studies have reported that septic shock is strongly associated with coagulation abnormality. The adenosine diphosphate (ADP) receptor antagonist, clopidogrel sulfate (CS), inhibits platelet function. Thus, we hypothesized that CS could inhibit LPS-induced systemic inflammation in a rat model. Male Wistar rats weighing 250 to 300 g received an LPS injection, followed 6 h later by filtration leukocytapheresis or mock treatment for 30 min under sevoflurane anesthesia. Five days before LPS injection, rats were given an oral dose of water or CS (10 mg/kg body weight). Levels of proinflammatory markers were determined in serum and tissue samples, and high-mobility group box 1 (HMGB1) expression was evaluated in lung and liver tissues. Compared with LPS-treated rats, induction of cytokines (IL-6 and TNF-α) was reduced in rats pretreated with CS. In addition, histological changes observed in lung and liver tissue samples of LPS-treated rats were attenuated in CS-pretreated rats. Clopidogrel sulfate pretreatment also reduced LPS-induced HMGB1 expression in lung and liver tissues. Collectively, our findings demonstrate that CS pretreatment may have value as a new therapeutic tool against systemic inflammation.

Interactions between coagulation and complement--their role in inflammation

The parallel expression of activation products of the coagulation, fibrinolysis, and complement systems has long been observed in both clinical and experimental settings. Several interconnections between the individual components of these cascades have also been described, and the list of shared regulators is expanding. The co-existence and interplay of hemostatic and inflammatory mediators in the same microenvironment typically ensures a successful host immune defense in compromised barrier settings. However, dysregulation of the cascade activities or functions of inhibitors in one or both systems can result in clinical manifestations of disease, such as sepsis, systemic lupus erythematosus, or ischemia-reperfusion injury, with critical thrombotic and/or inflammatory complications. An appreciation of the precise relationship between complement activation and thrombosis may facilitate the development of novel therapeutics, as well as improve the clinical management of patients with thrombotic conditions that are characterized by complement-associated inflammatory responses.

Defects in coagulation encountered in small animal critical care

Critically ill small animals are at risk for developing coagulation abnormalities. The processes of inflammation and coagulation are intertwined, and severe inflammation can lead to disturbances of coagulation. Severe coagulation dysfunction is associated with increased morbidity and mortality. Pathophysiology, diagnosis, and treatment of coagulation dysfunction are discussed. Defects in coagulation in small animal patients are complex and a consensus on diagnosis and treatment has yet to be reached.

Endothelin-1 signaling promotes fibrosis in vitro in a bronchopulmonary dysplasia model by activating the extrinsic coagulation cascade

Neonatal respiratory distress syndrome can progress to bronchopulmonary dysplasia (BPD), a serious pulmonary fibrotic disorder. Given the involvement of the extrinsic coagulation cascade in animal models of lung fibrosis, we examined its role in BPD. We observed a higher number of neutrophils expressing tissue factor (TF) in bronchoalveolar lavage fluid (BALF) from infants with BPD than from those with uncomplicated respiratory distress syndrome together with a parallel decrease in TF and connective tissue growth factor (CTGF) in BALF supernatants during the disease course. The involvement of coagulation in the fibrotic process associated with BPD was further evaluated by treating primary human colonic myofibroblasts with BALF supernatants from infants with BPD. These human colonic myofibroblasts demonstrated an enhanced C5a- and thrombin-dependent migration. Moreover, they expressed TF in an endothelin-1-dependent manner, with subsequent activation of the extrinsic coagulation cascade and CTGF production mediated by protease-activator receptor-1 signaling. These data provide a novel mechanism for the development of BPD and indicate that endothelin-1 signaling contributes to fibrosis by upregulating a TF/thrombin amplification loop responsible for CTGF production, and offer novel and specific therapeutic targets for pulmonary fibrotic disease.

Haematological interventions for treating disseminated intravascular coagulation during pregnancy and postpartum

BACKGROUND

Disseminated intravascular coagulation (DIC) is an acquired syndrome characterised by systemic intravascular activation of coagulation. There are several obstetric causes of DIC during pregnancy and postpartum.

OBJECTIVES

To assess the clinical effectiveness and safety of haematological interventions such as heparins (low molecular weight heparin (LMWH) and unfractionated heparin (UFH), danaparoid sodium, synthetic protease inhibitor, antithrombin, human recombinant activated protein C, recombinant human soluble thrombomodulin, recombinant tissue factor pathway inhibitor, recombinant activated factor VIIa and any other types of haematological interventions (except transfusions) for treating DIC during pregnancy and postpartum.

SEARCH STRATEGY

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (27 July 2010), LILACS (1982 to 22 July 2010), ongoing trials registries via the World Health Organization International Clinical Trials Platform Search Portal (22 July 2010), and other relevant websites (22 July 2010).

SELECTION CRITERIA

Randomised controlled trials (RCTs) on any haematological interventions for treating DIC during pregnancy and postpartum.

DATA COLLECTION AND ANALYSIS

There were no included studies.

MAIN RESULTS

We could not find any RCTs on haematological interventions (heparins (LMWH and UFH), danaparoid sodium, synthetic protease inhibitor, antithrombin, human recombinant activated protein C, recombinant human soluble thrombomodulin, recombinant tissue factor pathway inhibitor, recombinant activated factor VIIa and any other types of haematological interventions) for treating DIC during pregnancy and postpartum.

AUTHORS' CONCLUSIONS

This review found no RCTs on the safety and efficacy of haematological interventions for treating DIC during pregnancy and postpartum. Such interventions need to be tested in RCTs assessing outcomes such as maternal death, perinatal death and safety.

Recombinant tissue factor pathway inhibitor in severe community-acquired pneumonia: a randomized trial

RATIONALE

Severe community-acquired pneumonia (sCAP) is a leading cause of death worldwide. Adjunctive therapies for sCAP are needed to further improve outcome. A systemic inhibitor of coagulation, tifacogin (recombinant human tissue factor pathway inhibitor) seemed to provide mortality benefit in the sCAP subgroup of a previous sepsis trial.

OBJECTIVES

Evaluate the impact of adjunctive tifacogin on mortality in patients with sCAP.

METHODS

A multicenter, randomized, placebo-controlled, double-blind, three-arm study was conducted from July 2005 to June 2008 at 188 centers in North and South America, Europe, South Africa, Asia, Australia, and New Zealand. Adults with sCAP were randomized to receive a continuous intravenous infusion of tifacogin 0.025 mg/kg/h, tifacogin 0.075 mg/kg/h, or matching placebo over 96 hours.

MEASUREMENTS AND MAIN RESULTS

Severity-adjusted 28-day all-cause mortality. Of 2,138 randomized patients, 946, 238, and 918 received tifacogin 0.025 mg/kg/h, tifacogin 0.075 mg/kg/h, and placebo, respectively. Tifacogin 0.075 mg/kg/h was discontinued after the first interim analysis according to prespecified futility criterion. The 28-day all-cause mortality rates were similar between the 0.025 mg/kg/h (18%) and placebo groups (17.9%) (P = 0.56). Greater reduction in prothrombin fragment 1+2 and thrombin antithrombin complexes levels relative to baseline throughout the first 96 hours was found with tifacogin 0.025 mg/kg/h than with placebo. The incidence of adverse events and serious adverse events were comparable between the tifacogin 0.025 mg/kg/h and placebo groups.

CONCLUSIONS

Tifacogin showed no mortality benefit in patients with sCAP despite evidence of biologic activity.

Comparison of thromboelastometry with procalcitonin, interleukin 6, and C-reactive protein as diagnostic tests for severe sepsis in critically ill adults

Introduction

Established biomarkers for the diagnosis of sepsis are procalcitonin, interleukin 6, and C-reactive protein. Although sepsis evokes changes of coagulation and fibrinolysis, it is unknown whether thromboelastometry can detect these alterations. We investigated whether thromboelastometry variables are suitable as biomarkers for severe sepsis in critically ill adults.

Methods

In the observational cohort study, blood samples were obtained from patients on the day of diagnosis of severe sepsis (n = 56) and from postoperative patients (n = 52), and clotting time, clot formation time, maximum clot firmness, alpha angle, and lysis index were measured with thromboelastometry. In addition, procalcitonin, interleukin 6, and C-reactive protein levels were determined. For comparison of biomarkers, receiver operating characteristic (ROC) curves were used, and the optimal cut-offs and odds ratios were calculated.

Results

In comparison with postoperative controls, patients with sepsis showed an increase in lysis index (97% ± 0.3 versus 92 ± 0.5; P < 0.001; mean and SEM) and procalcitonin (2.5 ng/ml ± 0.5 versus 30.6 ± 8.7; P < 0.001). Clot-formation time, alpha angle, maximum clot firmness, as well as interleukin 6 and C-reactive protein concentrations were not different between groups; clotting time was slightly prolonged. ROC analysis demonstrated an area under the curve (AUC) of 0.901 (CI 0.838 - 0.964) for the lysis index, and 0.756 (CI 0.666 - 0.846) for procalcitonin. The calculated cut-off for the lysis index was > 96.5%, resulting in a sensitivity of 84.2%, and a specificity of 94.2%, with an odds ratio of 85.3 (CI 21.7 - 334.5).

Conclusions

The thromboelastometry lysis index proved to be a more reliable biomarker of severe sepsis in critically ill adults than were procalcitonin, interleukin 6, and C-reactive protein. The results also demonstrate that early involvement of the hemostatic system is a common event in severe sepsis.

Physical and occupational therapy for children with rheumatic diseases

Total management of rheumatic disorders of children includes antiinflammatory drugs, active therapy, maintenance of ADLs, and attention to the psychosocial development of the child. This article focuses on the role that physical and occupational therapists play in the management of children with arthritis. The complexity of the problems of these children necessitates a multidisciplinary team approach, with professionals who are committed to helping the child lead as normal a life as possible. This objective can be accomplished only by teaching families and school personnel how to manage the child's daily therapeutic needs.