Prognostic value of a simple evolving disseminated intravascular coagulation score in patients with severe sepsis

Evaluation of modified non-overt DIC criteria on the prediction of poor outcome in patients with sepsis

BACKGROUND

The diagnostic performance of modified criteria for non-overt disseminated intravascular coagulation (DIC) with the addition of antithrombin (AT) levels, protein C (PC) levels, and organ system failure scoring (OSF) to the International Society on Thrombosis and Hemostasis (ISTH) criteria for non-overt DIC was studied to determine the effect on predicting poor outcome in patients with sepsis.

METHODS

In total, 135 consecutive patients were studied. Hemostatic markers (platelet count, prothrombin time, D-dimer, AT, PC) were examined on days 0, 1, 2, 3, 4, and 7. ISTH overt and non-overt DIC scoring, OSF, and 28-day mortality were analyzed.

RESULTS

The numbers of patients with overt DIC, non-overt DIC and non-DIC were 42, 17 and 76 respectively. The 28-day mortality rates for ISTH overt DIC, ISTH non-overt DIC, and non-DIC were 47.6, 47.1, and 9.2%, respectively. By adding AT and PC to the ISTH non-overt DIC criteria, the 28-day mortality rate of overt DIC, non-overt DIC, and non-DIC changed to 47.6, 25.0, and 6.7%, respectively. By adding OSF to the ISTH non-overt DIC criteria to predict 28-day mortality in septic patients, receiver operating characteristic (ROC) curve analysis demonstrated that the area under the curve (AUC) of ISTH non-overt DIC (0.777) was significantly increased to 0.878 (P=0.018). However, neither AT nor PC increased the AUC.

CONCLUSIONS

Addition of OSF to the ISTH criteria for non-overt DIC gives a better prediction of poor outcome in patients with sepsis.

Six-month follow-up of patients with in-hospital thrombocytopenia during heparin-based anticoagulation (from the Complications After Thrombocytopenia Caused by Heparin [CATCH] registry)

Thrombocytopenia is a predictor of adverse outcomes in patients with acute coronary syndromes and in critically ill patients. The Complications After Thrombocytopenia Caused by Heparin (CATCH) registry was designed to explore the incidence, management, and clinical consequences of in-hospital thrombocytopenia occurring during heparin-based anticoagulation in diverse clinical settings. We conducted a prospective observational study of 37 United States hospitals participating in the CATCH registry to assess the relation of in-hospital thrombocytopenia to long-term outcomes. A total of 2,104 patients at increased risk of developing in-hospital thrombocytopenia or thrombosis were identified, and the 6-month mortality and rehospitalization rates were determined. Thrombocytopenia was not a significant predictor of 6-month mortality. In an adjusted model for in-hospital death in this cohort, thrombocytopenia had an odds ratio of 3.59 (95% confidence interval 2.24 to 5.77). The postdischarge mortality rate at 6 months was 9.7%. No significant difference was observed in the long-term mortality between patients who developed thrombocytopenia and those who did not. Thrombocytopenia was a weak, but statistically significant, predictor of a composite of mortality and rehospitalization at 6 months (hazards ratio 0.80, 95% confidence interval 0.65 to 0.98, p = 0.03). In conclusion, the 6-month mortality rate among heparin-treated patients with thrombocytopenia is high, although the risk independently related to thrombocytopenia appears to be restricted to the acute hospital phase.

Tissue factor pathway inhibitor and P-selectin as markers of sepsis-induced non-overt disseminated intravascular coagulopathy

Inflammation and coagulation occur concomitantly in sepsis. Thrombin activates platelet that leads to P-selectin translocation, which upregulate tissue factor (TF) generation. Tissue factor pathway inhibitor (TFPI) is an anticoagulant that modulates coagulation induced by TF. The term non-overt disseminated intravascular coagulation (DIC) refers to a state of affairs prevalent before the occurrence of overt DIC. It was suggested that an initiation of treatment in non-overt DIC has better outcome than overt DIC. This study investigated the role of TFPI level, P-selectin, and thrombin activation markers in non-overt and overt DIC induced by sepsis and its relationship to outcome and organ dysfunction as measured by the Sequential Organ Failure Assessment (SOFA) score. It included 176 patients with sepsis. They were admitted to the pediatric intensive care unit (ICU).They included 144 cases of non-overt DIC and 32 cases of overt DIC. There was a significant difference in hemostatic markers, platelet count, partial thromboplastin time (PTT), P-selectin, thrombin activation markers, TFPI, and DIC score between overt and non-overt DIC in both groups. It was noticed that P-selectin was positively correlated with DIC score, fibrinogen consumption, fibrinolysis (D-dimer), thrombin activation markers, and TFPI. Tissue factor pathway inhibitor was significantly correlated with fibrinolysis, DIC score, and prothrombin fragment 1+2. Sequential Organ Failure Assessment score was correlated with DIC score and other hemostatic markers in patients with overt DIC. To improve the outcome of patients with DIC, there is a need to establish more diagnostic criteria for non-overt-DIC. Plasma levels of TFPI and P-selectin may be helpful in this respect.

The response of antithrombin III activity after supplementation decreases in proportion to the severity of sepsis and liver dysfunction

The decrease in the antithrombin III activity is thought to result from consumption by ongoing coagulation, degradation by neutrophil elastase, capillary leak syndrome, and impaired synthesis. A retrospective data analysis of patients with sepsis was conducted to investigate the response of antithrombin III activity after supplementation in patients with sepsis, and to determine what factors affect the response of antithrombin III activity. The study included 42 patients with sepsis, 75 patients with severe sepsis, and 65 patients with septic shock, who were administered antithrombin III. Antithrombin III activity, platelet counts, coagulation, and fibrinolytic markers were collected before administration and 24 h after the supplementation. In the patients with septic shock, the response of antithrombin III activity after supplementation was 0.37% +/- 1.21%/IU per kg body weight, which was significantly lower in comparison with those in the patients with sepsis (1.81 +/- 1.75; P < 0.001) or severe sepsis (1.36 +/- 1.65; P < 0.001). The patients with liver dysfunction had significantly lower response to antithrombin III activity than that of the patients without liver dysfunction (P < 0.0001). A stepwise multiple linear regression analysis revealed that the severity of sepsis and liver function were independent predictors for the response to antithrombin III activity. These results suggest that the response to antithrombin III supplementation may be affected by both a systemic inflammation and impaired synthesis in patients with sepsis.

Disseminated intravascular coagulation score is associated with mortality for children with shock

OBJECTIVE

To evaluate the association between disseminated intravascular coagulation (DIC) score and mortality for children with shock.

DESIGN

Retrospective.

SETTING

Tertiary care, 20-bed pediatric intensive care unit.

PATIENTS

A total of 132 children with sepsis or shock admitted from January 2003 to December 2005.

MEASUREMENTS AND RESULTS

A total of 132 patients less than 18 years of age with a diagnosis of shock or sepsis were included in the analysis. Of these patients, 90 survived and 42 died (31.8%). Patients ranged from 6 days to 18 years (median 5.8 years), and were a majority male (63%). Variables associated with mortality included peak DIC score within 24 h of ICU admission, age, weight, volume of blood products transfused, inotrope score, pediatric index of mortality (PIM 2) score, 12-h pediatric risk of mortality (PRISM III) score and presence of mechanical ventilation (P < 0.05). Patients with DIC scores >or= 5 (overt DIC) had 50% mortality, compared to 20% for patients with DIC scores < 5. Overall, a one-point rise in DIC score was associated with an increased risk of mortality after adjusting for age, race, gender, hemodynamic instability, and PRISM III score [OR 1.35 (1.02, 1.78)]. Most patients achieve their peak DIC score within 2 h of ICU admission.

CONCLUSIONS

This analysis suggests that DIC score, easily calculated early in ICU admission, is associated with mortality for children with sepsis and shock, regardless of initial severity of illness or inotrope use.

A laboratory-based risk score for medical intensive care patients

BACKGROUND

Established general risk score models for intensive care patients incorporate several clinical and laboratory data. However, the collection, documentation and classification of clinical data are time-consuming, incur labor-related costs, and are dependent on the experience of the examiner. Therefore, in the present study a general score for medical intensive care patients based solely on routine laboratory parameters is presented.

METHODS

Parameter selection was performed using stepwise logistic regression analysis. The maximum likelihood estimate of variable influence on mortality provided a relative weighting for each variable. The new score was compared to two established risk models (Acute Physiology And Chronic Health Evaluation II, APACHE II; and Simplified Acute Physiology Score II, SAPS II).

RESULTS

The study included 528 medical intensive care patients with a mean age of 65.4+/-0.7 years. The in-hospital mortality was 16.5% (87/528). Multiple logistic regression analysis revealed eight parameters with significant prognostic power: alanine aminotransferase, cholesterol, creatinine, leukocytes, sodium, thrombocytes, urea, and age. These parameters were used to build a new laboratory score called Critical Risk Evaluation by Early Keys (CREEK). The area under the receiver operating characteristics curve was 0.857 (0.814-0.900). Pearson correlation analysis showed significant correlation between CREEK and APACHE II (r=0.550) and SAPS II (r=0.516; p<0.001; n=387). The areas under curve of the APACHE II and the SAPS II were 0.869 and 0.874, respectively.

CONCLUSIONS

We show that a general risk score for medical intensive care patients on admission based solely on routine laboratory parameters is feasible. The quality of risk estimation using CREEK is comparable to established risk models. Furthermore, this new score is based on quality controlled low-cost laboratory parameters that are routinely measured on admission to the intensive care unit. Therefore, no additional costs are involved.

Microfluidic device for label-free measurement of platelet activation

In this work we demonstrate a new microfluidic method for the rapid assessment of platelet size and morphology in whole blood. The device continuously fractionates particles according to size by displacing them perpendicularly to the fluid flow direction in a micro-fabricated post array. Whole blood, labeled with the fluorescent, platelet specific, antibody PE-anti-CD41, was run through the device and the positions of fluorescent objects noted as they exited the array. From this, histograms of platelet size were created which show marked increases in size after exposure to thrombin or a temperature of 4 degrees C. We infer that the well known morphological changes that occur during activation are causing the observed increase in size.

Procalcitonin assay in systemic inflammation, infection, and sepsis: clinical utility and limitations

OBJECTIVE

The use of procalcitonin (ProCT) as a marker of several clinical conditions, in particular, systemic inflammation, infection, and sepsis, will be clarified, and its current limitations will be delineated. In particular, the need for a more sensitive assay will be emphasized. For these purposes, the medical literature comprising clinical studies pertaining to the measurement of serum ProCT in various clinical settings was examined.

DATA SOURCE AND SELECTION

A PubMed search (1965 through November 2007) was conducted, including manual cross-referencing. Pertinent complete publications were obtained using the MeSH terms procalcitonin, C-reactive protein, sepsis, and biological markers. Textbook chapters were also read and extracted.

DATA EXTRACTION AND SYNTHESIS

Available clinical and other patient data from these sources were reviewed, including any data relating to precipitating factors, clinical findings, associated illnesses, and patient outcome. Published data concerning sensitivity, specificity, and reproducibility of ProCT assays were reviewed.

CONCLUSIONS

Based on available data, the measurement of serum ProCT has definite utility as a marker of severe systemic inflammation, infection, and sepsis. However, publications concerning its diagnostic and prognostic utility are contradictory. In addition, patient characteristics and clinical settings vary markedly, and the data have been difficult to interpret and often extrapolated inappropriately to clinical usage. Furthermore, attempts at meta-analyses are greatly compromised by the divergent circumstances of reported studies and by the sparsity and different timing of the ProCT assays. Although a high ProCT commonly occurs in infection, it is also elevated in some noninfectious conditions. Thus, the test is not a specific indicator of either infection or sepsis. Moreover, in any individual patient, the precipitating cause of an illness, the clinical milieu, and complicating conditions may render tenuous any reliable estimations of severity or prognosis. It also is apparent that even a febrile septic patient with documented bacteremia may not necessarily have a serum ProCT that is elevated above the limit of functional sensitivity of the assay. In this regard, the most commonly applied assay (i.e., LUMItest) is insufficiently sensitive to detect potentially important mild elevations or trends. Clinical studies with a more sensitive ProCT assay that is capable of rapid and practicable day-to-day monitoring are needed and shortly may be available. In addition, investigations showing that ProCT and its related peptides may have mediator relevance point to the need for evaluating therapeutic countermeasures and studying the pathophysiologic effect of hyperprocalcitonemia in serious infection and sepsis.

Natural history of disseminated intravascular coagulation diagnosed based on the newly established diagnostic criteria for critically ill patients: results of a multicenter, prospective survey

OBJECTIVE

To survey the natural history of disseminated intravascular coagulation (DIC) in patients diagnosed according to the Japanese Association for Acute Medicine (JAAM) DIC scoring system in a critical care setting.

DESIGN

Prospective, multicenter study during a 4-month period.

SETTING

General critical care center in a tertiary care hospital.

PATIENTS

All patients were enrolled when they were diagnosed as DIC by the JAAM DIC scoring system.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Platelet counts, prothrombin time ratio, fibrinogen, and fibrin/fibrinogen degradation products were measured, and the systemic inflammatory response syndrome criteria met by the patients were determined following admission. Of 3,864 patients, 329 (8.5%) were diagnosed with DIC and the 28-day mortality rate was 21.9%, which was significantly different from that of the non-DIC patients (11.2%) (p < .0001). The progression of systemic inflammation, deterioration of organ function, and stepwise increase in incidence of the International Society on Thrombosis and Haemostasis (ISTH) DIC and its scores all correlated with an increase in the JAAM DIC score as demonstrated by the patients on day 0. There were significant differences in the JAAM DIC score and the variables adopted in the scoring system between survivors and nonsurvivors. The logistic regression analyses showed the JAAM DIC score and prothrombin time ratio on the day of DIC diagnosis to be predictors of patient outcome. The patients who simultaneously met the ISTH DIC criteria demonstrated twice the incidence of multiple organ dysfunction (61.1 vs. 30.5%, p < .0001) and mortality rate (34.4 vs. 17.2%, p = .0015) compared with those without the ISTH DIC diagnosis.

CONCLUSIONS

This prospective survey demonstrated the natural history of DIC patients diagnosed by the JAAM DIC diagnostic criteria in a critical care setting. The study provides further evidence of a progression from the JAAM DIC to the ISTH overt DIC.

Disseminated intravascular coagulation

OBJECTIVE

To review the current knowledge on the clinical manifestation, pathogenesis, diagnosis, and management of disseminated intravascular coagulation (DIC).

DATA SOURCE

Selected articles from the MEDLINE database.

DATA SYNTHESIS

DIC may complicate a variety of disorders and can cause significant morbidity (in particular related to organ dysfunction and bleeding) and may contribute to mortality. The pathogenesis of DIC is based on tissue factor-mediated initiation of systemic coagulation activation that is insufficiently contained by physiologic anticoagulant pathways and amplified by impaired endogenous fibrinolysis. The diagnosis of DIC can be made using routinely available laboratory tests and scoring algorithms. Supportive treatment of DIC may be aimed at replacement of platelets and coagulation factors, anticoagulant treatment, and restoration of anticoagulant pathways.

CONCLUSIONS

Insight into the pathogenesis of DIC has resulted in better strategies for clinical management, including straightforward diagnostic criteria and potentially beneficial supportive treatment options.

Markers of inflammation as determinants of mortality in intensive care unit patients

In this study, the investigators explored the relationship between mortality rate and serum levels of C-reactive protein (CRP), erythrocyte sedimentation ratio (ESR), albumin, and hemoglobin, leukocyte, and platelet counts of patients at the time of first admission to the intensive care unit (ICU). A total of 123 patients were admitted to 2 different ICUs. In the emergency departments, serum levels of CRP, ESR, and albumin and hematologic parameters of 81 patients who died and 42 patients who survived were compared. A Student t test and the chi2 test were used for statistical analyses. Mean CRP and ESR levels and leukocyte counts were higher in nonsurvivor than in survivor groups (P<.001 for all). Additionally, serum CRP and ESR elevations and leukocyte counts were determined to be individually related to mortality (P<.001, P<.05, and P<.05, respectively). The investigators concluded that initial serum levels of CRP and ESR and leukocyte counts can be used as determinants of mortality in ICU patients.

Coagulation disorder as a prognostic factor for patients with colorectal perforation

BACKGROUND

Although sepsis after surgery for colorectal perforation frequently results in severe coagulation disorders and consequent death of the patient, the correlation between coagulation abnormalities and postoperative mortality of colorectal perforation has not been clarified.

METHODS

The medical records of 101 consecutive patients receiving surgery for colorectal perforations between January 1994 and July 2006 were retrospectively reviewed. The abnormalities of preoperative laboratory data reflecting coagulation disorders and other possible risk factors were analyzed by univariate and multivariate analysis.

RESULTS

Prolonged prothrombin time and activated partial thromboplastin time significantly correlated with a poor prognosis (both P < 0.001). Among the several risk factors analyzed, only the presence of coagulation disorders was an independent predictive factor of postoperative mortality.

CONCLUSIONS

Prolonged prothrombin time and activated partial thromboplastin time are useful prognostic factors for predicting the surgical outcome for patients with colorectal perforation.

Acute inflammation is exacerbated in mice genetically predisposed to a severe protein C deficiency

The anticoagulant, activated protein C (aPC), possesses antithrombotic, profibrinolytic, anti-inflammatory, and antiapoptotic properties, and the level of this protein is an important marker of acute inflammatory responses. Although infusion of aPC improves survival in a subset of patients with severe sepsis, evidence as to how aPC decreases mortality in these cases is limited. Because a total deficiency of PC shows complete neonatal lethality, no animal model currently exists to address the mechanistic relationships between very low endogenous aPC levels and inflammatory diseases. Here, we show for the first time that novel genetic dosing of PC strongly correlates with survival outcomes following endotoxin (LPS) challenge in mice. The data provide evidence that very low endogenous levels of PC predispose mice to early-onset disseminated intravascular coagulation, thrombocytopenia, hypotension, organ damage, and reduced survival after LPS challenge. Furthermore, evidence of an exacerbated inflammatory response is observed in very low PC mice but is greatly reduced in wild-type cohorts. Reconstitution of low-PC mice with recombinant human aPC improves hypotension and extends survival after LPS challenge. This study directly links host endogenous levels of PC with various coagulation, inflammation, and hemodynamic end points following a severe acute inflammatory challenge.

Clinical laboratory findings associated with in-hospital mortality

The diagnostic approach and the clinical management of critically ill patients is challenging. The recognition of biomarkers related to in-hospital mortality is of importance for identification of patients at increased risk of death. Many prediction models assessing the severity of illness and likelihood of hospital survival were developed using logistic regression analyses. These models include several laboratory parameters, such as white blood cell counts, serum bilirubin, serum albumin, blood glucose, serum electrolytes and markers which reflect acid-base disturbances. Recently, several other biomarkers, including troponin, B-type natriuretic peptide (BNP), N-terminal proBNP, C-reactive protein, procalcitonin, cholesterol and coagulation related markers have emerged as clinically useful tools for risk stratification and mortality prediction of heterogeneous and more specific subgroups of critically ill patients. More investigations are required to verify whether risk stratification based on mortality-related biomarkers may translate into targeted treatment strategies to improve clinical outcome of the critical illness. Biomarkers which are related to in-hospital mortality are highlighted in the current review.