The usefulness of antithrombin activity monitoring during antithrombin supplementation in patients with sepsis-associated disseminated intravascular coagulation

Determining prognostic indicator for anticoagulant therapy in sepsis-induced disseminated intravascular coagulation

BACKGROUND

There is no reliable indicator that can assess the treatment effect of anticoagulant therapy for sepsis-associated disseminated intravascular coagulation (DIC) in the short term. The aim of this study is to develop and validate a prognostic index identifying 28-day mortality in septic DIC patients treated with antithrombin concentrate after a 3-day treatment.

METHODS

The cohort for derivation was established utilizing the dataset from post-marketing surveys, while the cohort for validation was acquired from Japan's nationwide sepsis registry data. Through univariate and multivariate analyses, variables that were independently associated with 28-day mortality were identified within the derivation cohort. Risk variables were then assigned a weighted score based on the risk prediction function, leading to the development of a composite index. Subsequently, the area under the receiver operating characteristic curve (AUROC). 28-day survival was compared by Kaplan-Meier analysis.

RESULTS

In the derivation cohort, 252 (16.9%) of the 1492 patients deceased within 28 days. Multivariable analysis identified DIC resolution (hazard ratio [HR]: 0.31, 95% confidence interval [CI]: 0.22-0.45, P < 0.0001) and rate of Sequential Organ Failure Assessment (SOFA) score change (HR: 0.42, 95% CI: 0.36-0.50, P < 0.0001) were identified as independent predictors of death. The composite prognostic index (CPI) was constructed as DIC resolution (yes: 1, no: 0) + rate of SOFA score change (Day 0 SOFA score-Day 3 SOFA score/Day 0 SOFA score). When the CPI is higher than 0.19, the patients are judged to survive. Concerning the derivation cohort, AUROC for survival was 0.76. As for the validation cohort, AUROC was 0.71.

CONCLUSION

CPI can predict the 28-day survival of septic patients with DIC who have undergone antithrombin treatment. It is simple and easy to calculate and will be useful in practice.

Risk stratification utilizing sequential organ failure assessment (SOFA) score, antithrombin activity, and demographic data in sepsis-associated disseminated intravascular coagulation (DIC)

Disseminated intravascular coagulation (DIC) is a frequent complication in patients with sepsis and is associated with increased mortality. Anticoagulant therapy may be appropriate for certain patients with DIC, particularly those with increased disease severity and deficiency in the physiologic anticoagulant antithrombin. We retrospectively analyzed post-marketing survey data from 1562 patients with sepsis-associated DIC and antithrombin activity of 70% or less. All the patients were treated with antithrombin concentrates. Baseline sequential organ failure assessment (SOFA) score, DIC score, and antithrombin activity were assessed. Cox multivariate regression analysis, Kaplan-Meier curve analysis, and receiver operating characteristic (ROC) curve analysis were performed to evaluate the performance of variables used to assess mortality. Furthermore, a decision tree was constructed to classify the risk of 28-day mortality. COX multivariate regression analysis demonstrated a significant association of age, sex, baseline SOFA score, baseline antithrombin activity, and the presence of pneumonia or skin/soft tissue infection with increased mortality. The area under the curve of SOFA score or antithrombin activity for mortality was 0.700 and 0.614, respectively. Kaplan-Meier analysis demonstrated that mortality was significantly higher in patients with SOFA score ≥ 12 and antithrombin activity < 47%. The decision tree analysis accurately classified the risk of death into high (> 40%), medium (40%-20%), and low (< 20%) categories in 86.1% of the cohort. Twenty eight-day mortality can be strongly predicted using baseline SOFA score, antithrombin activity, infection site, age, and sex as variables in the clinical decision tree for patients with sepsis-associated disseminated intravascular coagulation (DIC).

The antithrombin activity recovery after substitution therapy is associated with improved 28-day mortality in patients with sepsis-associated disseminated intravascular coagulation

BACKGROUND

Disseminated intravascular coagulation (DIC) is a common and critical complication in sepsis. Antithrombin activity, which is considered a biomarker for disease severity, was measured in septic DIC treated with antithrombin concentrates in this study.

METHODS

We conducted a retrospective analysis of post-marketing survey data that included 1,800 patients with sepsis-associated DIC and antithrombin activity of 70% or less who were treated with antithrombin concentrates. The changes in sequential organ failure assessment (SOFA) score, DIC score, and antithrombin activity were sequentially assessed. Logistic regression analysis and receiver operating characteristic (ROC) curve analysis were performed to evaluate the performance of antithrombin activity to assess 28-day survival. Furthermore, the relationship between post-treatment antithrombin activity and survival was examined by Logistic regression analysis.

RESULTS

Sex, baseline SOFA score, baseline antithrombin activities, and the presence of pneumonia and soft tissue infection were significantly associated with 28-day mortality. The area under the curve for mortality was 0.639 for post-treatment antithrombin activity, and higher than those of baseline- and delta antithrombin activities. Logistic regression analysis revealed that higher post-treatment antithrombin activity was associated with better 28-day survival. When post-treatment antithrombin activity was more than 80%, the estimated survival was 88.2%. Whereas, the survival was 74.4% when the antithrombin activity was 80% or less (P < 0.0001). However, the relationship between post-treatment antithrombin activity and 28-day survival was considerably different between patients who recovered from DIC by Day 6 compared to those who did not. Similarly, the estimated 28-day survival, based on antithrombin activity, varied among patients with high and low SOFA scores, and the calculation needs to be adjusted based on the severity of the condition.

CONCLUSIONS

Post-treatment antithrombin activity measurement was helpful in estimating the 28-day survival in patients with sepsis-associated DIC. However, patient outcomes vary considerably depending on factors that include baseline SOFA score, age, and baseline antithrombin activity. These variables play a substantial role in determining patient prognosis and should be considered when evaluating and interpreting the results.

Association of antithrombin with development of trauma-induced disseminated intravascular coagulation and outcomes

Introduction

Trauma activates the innate immune system to modulate hemostasis and minimize the damage caused by physiological bodily responses, including the activation of coagulation. Sufficiently severe trauma overwhelms physiological responses and elicits the systemic inflammatory response syndrome, which leads to the onset of disseminated intravascular coagulation (DIC), characterized by dysregulated inflammatory coagulofibrinolytic responses. Impaired anticoagulant mechanisms, including antithrombin, constitutes the pathology of DIC, while the dynamics of antithrombin and relevance to outcomes in trauma-induced coagulopathy have not been fully elucidated. This study investigated the associations of antithrombin activity with DIC onset and outcomes in severely injured patients.

Methods

This retrospective sub-analysis of a multicenter, prospective study included patients with an injury severity score ≥16. We characterized trauma patients with low antithrombin activity (antithrombin <80% on hospital arrival, n = 75) in comparison with those who had normal antithrombin activity (antithrombin ≥80%, n = 200). Global markers of coagulation and fibrinolysis, molecular biomarkers for thrombin generation (soluble fibrin [SF]), and markers of anticoagulation (antithrombin) were evaluated to confirm the associations of antithrombin with DIC development and outcomes, including in-hospital mortality and the multiple organ dysfunction syndrome (MODS).

Results

Patients with low antithrombin activity had higher prevalence of shock, transfusion requirements, and in-hospital mortality. Higher DIC scores and more severe organ dysfunction were observed in the low AT group compared to that in the normal AT group. Antithrombin activity on arrival at the hospital was an independent predictor of the development of DIC in trauma patients, and levels of SF increased with lower antithrombin values (antithrombin activity > 85%). Antithrombin activity at 3 h showed good predictive performance for in-hospital mortality, and a multivariable Cox proportional-hazard regression model with a cross-product term between the antithrombin and DIC showed that the in-hospital mortality in patients with DIC increased with decreased antithrombin activity. A multivariable logistic regression model showed that the odds for the development of MODS in patients with DIC increased with lower antithrombin values.

Conclusion

Decreased antithrombin activity in trauma-induced coagulopathy is associated with poor outcomes through worsening of DIC.

Anticoagulation Management during Extracorporeal Membrane Oxygenation-A Mini-Review

Extracorporeal membrane oxygenation (ECMO) has been established as a life-saving technique for patients with the most severe forms of respiratory or cardiac failure. It can, however, be associated with severe complications. Anticoagulation therapy is required to prevent ECMO circuit thrombosis. It is, however, associated with an increased risk of hemocoagulation disorders. Thus, safe anticoagulation is a cornerstone of ECMO therapy. The most frequently used anticoagulant is unfractionated heparin, which can, however, cause significant adverse effects. Novel drugs (e.g., argatroban and bivalirudin) may be superior to heparin in the better predictability of their effects, functioning independently of antithrombin, inhibiting thrombin bound to fibrin, and eliminating heparin-induced thrombocytopenia. It is also necessary to keep in mind that hemocoagulation tests are not specific, and their results, used for setting up the dosage, can be biased by many factors. The knowledge of the advantages and disadvantages of particular drugs, limitations of particular tests, and individualization are cornerstones of prevention against critical events, such as life-threatening bleeding or acute oxygenator failure followed by life-threatening hypoxemia and hemodynamic deterioration. This paper describes the effects of anticoagulant drugs used in ECMO and their monitoring, highlighting specific conditions and factors that might influence coagulation and anticoagulation measurements.

Thrombin generation capacity is enhanced by low antithrombin activity and depends on the activity of the related coagulation factors

Background

Supplementation with antithrombin (AT) concentrates is now common in the treatment of congenital and acquired AT deficiency. However, there is no established consensus on the target and timing of supplementation. We aimed to elucidate the effects of AT deficiency on the balance between coagulation activation and inhibition using a thrombin generation assay as in vitro global assay.

Methods

Samples were prepared by admixing commercially acquired AT-deficient plasma with < 1% AT activity with pooled normal plasma. The AT activity in each sample was adjusted to 100, 90, 70, 50, 40, 30, 10, 5, and < 1%. A thrombin generation assay was performed in each sample. AT concentrate-spiked samples were also prepared by adjusting the AT activities in four types of the concentrates: one recombinant and three plasma-derived AT concentrates. The final targeted AT activities in the samples were adjusted to 100, 50, 30, and 5% by spiking each concentrate into the AT-deficient plasma. We also prepared samples with five levels of prothrombin time (PT) % in coagulation factors with the AT activity fixed at 30% by dilution by mixing AT-deficient plasma and normal plasma with Owren’s veronal buffer to adjust the coagulation factor activities in several proportions. The theoretical target PT% values were 100, 66, 50, 40, and 30%. A thrombin generation assay was performed on all samples.

Results

The ability to generate thrombin depended on the AT activity, and the amount of thrombin generation was increased as AT was decreased. Additionally, the amount of thrombin generation was changed significantly when AT activity was ≤ 50%, indicating that AT suppressed thrombin generation. In particular, thrombin generation was remarkable when AT activity was < 30%, and it can be assumed that the prognosis is poor due to organ failure from thrombotic tendency.

Conclusions

The results presented in this basic research were found to be consistent with the clinical findings to date. The mechanism by which 30–50% of AT activity is set as the clinical boundary was elucidated by the thrombin generation assay.

Impact of Antithrombin Activity Levels Following Recombinant Antithrombin Gamma Therapy in Patients with Sepsis-Induced Disseminated Intravascular Coagulation

Recombinant antithrombin gamma (rAT) is reported as an effective drug for patients with disseminated intravascular coagulation (DIC) in Japan. As the appropriate dose and targeted AT activity remain unknown, this study aimed to determine these aspects for sepsis-induced DIC. Thirty-one patients with septic shock and DIC with AT levels <70% were treated with rAT between May 2018 and December 2020. The recovery rates from DIC were 32.2% and 63.3% on day 3 and 5 post administration, respectively. Recovery and survival rates were significantly higher in patients who achieved AT activity ≥70% or 80% on day 3 post administration. Receiver operating characteristic curve analysis revealed that the cutoff values of post-treatment AT activity on day 3 for 28-day survival and 5-day recovery from DIC were 79.5% and 81.5%, respectively. Patients who did not achieve AT activity ≥80% on day 3 presented a lower base level of AT activity and lower dose supplementation. Our results suggest that targeted AT activity should be at least 70%, and ideally 80%, and sufficient doses to maintain this activity are required to achieve better outcomes.

Antithrombin and Its Role in Host Defense and Inflammation

Antithrombin (AT) is a natural anticoagulant that interacts with activated proteases of the coagulation system and with heparan sulfate proteoglycans (HSPG) on the surface of cells. The protein, which is synthesized in the liver, is also essential to confer the effects of therapeutic heparin. However, AT levels drop in systemic inflammatory diseases. The reason for this decline is consumption by the coagulation system but also by immunological processes. Aside from the primarily known anticoagulant effects, AT elicits distinct anti-inflammatory signaling responses. It binds to structures of the glycocalyx (syndecan-4) and further modulates the inflammatory response of endothelial cells and leukocytes by interacting with surface receptors. Additionally, AT exerts direct antimicrobial effects: depending on AT glycosylation it can bind to and perforate bacterial cell walls. Peptide fragments derived from proteolytic degradation of AT exert antibacterial properties. Despite these promising characteristics, therapeutic supplementation in inflammatory conditions has not proven to be effective in randomized control trials. Nevertheless, new insights provided by subgroup analyses and retrospective trials suggest that a recommendation be made to identify the patient population that would benefit most from AT substitution. Recent experiment findings place the role of various AT isoforms in the spotlight. This review provides an overview of new insights into a supposedly well-known molecule.

Risk factors and treatments for disseminated intravascular coagulation in neonates

Background

Although disseminated intravascular coagulation (DIC) is a critical disease, there is few gold standard interventions in neonatal medicine. The aim of this study is to reveal factors affecting neonatal DIC at birth and to assess the effectiveness of rTM and FFP for DIC in neonates at birth.

Methods

We retrospectively evaluated DIC score on the first day of life in neonates with underlying conditions associated with DIC. DIC in neonates was diagnosed according to Japan Society of Obstetrical, Gynecological & Neonatal Hematology 2016 neonatal DIC criteria.

Results

Comparing neonates with DIC scores of ≥3 (n = 103) to those < 3 (n = 263), SGA, birth asphyxia, low Apgar score, hemangioma, hydrops, PIH, and PA were statistically increased. Among 55 neonates underwent DIC treatment, 53 had birth asphyxia and 12 had intraventricular hemorrhage. Forty-one neonates received FFP or a combination of FFP and antithrombin (FFP group), while 14 neonates received rTM or a combination of rTM, FFP, and antithrombin (rTM group). DIC score before treatment in the rTM group was significantly higher than in the FFP group (4.7 vs 3.6, P < 0.05). After treatment, DIC scores in both groups were significantly reduced on Day 1 and Day 2 (P < 0.05).

Conclusions

Among various factors associated with DIC in neonates at birth, birth asphyxia is particularly significant. Furthermore, rTM in combination with FFP therapy was effective for neonatal DIC at birth.

Usefulness of Measuring Changes in SOFA Score for the Prediction of 28-Day Mortality in Patients With Sepsis-Associated Disseminated Intravascular Coagulation

The primary end point for sepsis trial is 28-day mortality. However, additional methods for determining the efficacy may have benefits. The purpose of this study was to search a useful indicator of anticoagulant therapy in patients with sepsis with disseminated intravascular coagulation (DIC). Data from 323 patients with sepsis with coagulopathy treated with antithrombin supplementation were analyzed. The changes in the Sequential Organ Failure Assessment (Δ SOFA) score, the overt-DIC (Δ overt-DIC) score, and the Japanese Society for Acute Medicine DIC (Δ JAAM DIC) score from baseline to day 7 were retrospectively analyzed in relation to the 28-day mortality. Significant correlations were found between the 28-day mortality and Δ SOFA, Δ overt-DIC score, and Δ JAAM DIC score. The accuracy of the prediction was higher for Δ SOFA (80.5%) than for Δ overt-DIC (66.7%, P < .001). The areas under the curve for mortality calculated using a receiver operating characteristic curve analysis were 0.812 for Δ SOFA, 0.655 for Δ overt-DIC, and 0.693 for Δ JAAM DIC. The mortality rate was significantly lower among cases with an improved SOFA score compared to those without an improvement. The Δ SOFA had the strongest association with the 28-day mortality in patients with sepsis and DIC.

Antithrombin deficiency is associated with mortality and impaired organ function in septic pediatric patients: a retrospective study

Background

Sepsis remains a major problem in intensive care medicine. It is often accompanied by coagulopathies, leading to thrombotic occlusion of small vessels with subsequent organ damage and even fatal multi-organ failure. Prediction of the clinical course and outcome—especially in the heterogeneous group of pediatric patients—is difficult. Antithrombin, as an endogenous anticoagulant enzyme with anti-inflammatory properties, plays a central role in controling coagulation and infections. We investigated the relationship between antithrombin levels and organ failure as well as mortality in pediatric patients with sepsis.

Methods

Data from 164 patients under the age of 18, diagnosed with sepsis, were retrospectively reviewed. Antithrombin levels were recorded three days before to three days after peak C-reactive protein to correlate antithrombin levels with inflammatory activity. Using the concept of developmental haemostasis, patients were divided into groups <1 yr and ≥1 yr of age.

Results

In both age groups, survivors had significantly higher levels of antithrombin than did deceased patients. An optimal threshold level for antithrombin was calculated by ROC analysis for survival: 41.5% (<1 yr) and 67.5% (≥1 yr). The mortality rate above this level was 3.3% (<1 yr) and 9.5% (≥1 yr), and below this level 41.7% (<1 yr) and 32.2% (≥1 yr); OR 18.8 (1.74 to 1005.02), p = 0.0047, and OR 4.46 (1.54 to 14.89), p = 0.003. In children <1 yr with antithrombin levels <41.5% the rate of respiratory failure (66.7%) was significantly higher than in patients with antithrombin levels above this threshold level (23.3%), OR 6.23 (1.23 to 37.81), p = 0.0132. In children ≥1 yr, both liver failure (20.3% vs 1.6%, OR 15.55 (2.16 to 685.01), p = 0.0008) and a dysfunctional intestinal tract (16.9% vs 4.8%, OR 4.04 (0.97 to 24.08), p = 0.0395) occurred more frequently above the antithrombin threshold level of 67.5%.

Conclusion

In pediatric septic patients, significantly increased mortality and levels of organ failure were found below an age-dependent antithrombin threshold level. Antithrombin could be useful as a prognostic marker for survival and occurrence of organ failure in pediatric sepsis.

A Proposal of the Modification of Japanese Society on Thrombosis and Hemostasis (JSTH) Disseminated Intravascular Coagulation (DIC) Diagnostic Criteria for Sepsis-Associated DIC

Sepsis-associated disseminated intravascular coagulation (DIC) carries a high risk of death. Thus, a simple tool to quickly establish DIC diagnosis is required. The purpose of this study was to introduce the simple and reliable tool for the prediction of outcome in patients with sepsis complicated by coagulopathy. We investigated the performance of simplified Japanese Society on Thrombosis and Hemostasis (JSTH) DIC diagnostic criteria. In this study, we conducted a retrospective, multicenter survey in 107 general emergency and critical care centers in secondary and tertiary care hospitals. A total of 918 patients with sepsis-associated coagulopathy who underwent antithrombin supplementation were examined. The relationships between patient mortality and each of the baseline (ie, before treatment) JSTH-DIC diagnostic criteria were examined. A reduced platelet count, increased prothrombin time (PT) ratio, and lower antithrombin activity were correlated with 28-day mortality, while fibrinogen and fibrin degradation product (FDP) level were not. Thus, the number of points assigned to FDP levels was reduced from 3 to 1 (above 20 μg/mL). The simplified JSTH diagnostic criteria combining platelet count, PT ratio, antithrombin activity, and FDP level (reduction in the maximum score) strongly predicted 28-day mortality and allowed us to diagnose a larger/similar number of patients with DIC as compared to the original JSTH-DIC. The simplified JSTH-DIC diagnostic criteria show a similar performance to JSTH-DIC criteria in patients with septic coagulopathy. The lower number of laboratory markers used in the simplified JSTH-DIC score may increase its applicability and routine use in emergency and critical care setting.

To What Extent Are the Terminal Stages of Sepsis, Septic Shock, Systemic Inflammatory Response Syndrome, and Multiple Organ Dysfunction Syndrome Actually Driven by a Prion/Amyloid Form of Fibrin?

A well-established development of increasing disease severity leads from sepsis through systemic inflammatory response syndrome, septic shock, multiple organ dysfunction syndrome, and cellular and organismal death. Less commonly discussed are the equally well-established coagulopathies that accompany this. We argue that a lipopolysaccharide-initiated (often disseminated intravascular) coagulation is accompanied by a proteolysis of fibrinogen such that formed fibrin is both inflammatory and resistant to fibrinolysis. In particular, we argue that the form of fibrin generated is amyloid in nature because much of its normal α-helical content is transformed to β-sheets, as occurs with other proteins in established amyloidogenic and prion diseases. We hypothesize that these processes of amyloidogenic clotting and the attendant coagulopathies play a role in the passage along the aforementioned pathways to organismal death, and that their inhibition would be of significant therapeutic value, a claim for which there is considerable emerging evidence.

The efficacy and associated bleeding complications of recombinant antithrombin supplementation among intensive care unit patients

INTRODUCTION

The aim of this study was to evaluate the efficacy and complications of recombinant antithrombin (rAT) supplementation for adult patients with disseminated intravascular coagulation (DIC) compared with conventional plasma derived AT (pAT) treatment in the intensive care unit.

MATERIALS AND METHODS

This study was performed in a single national university hospital in Japan. Adult patients from April 2015 to March 2016 with DIC were divided into two groups based on the type of AT agent used: the pAT group (n=24) and the rAT group (n=21). Patient demographics, medical history, diagnosis, blood tests, various clinical scores, AT activity, complications, and clinical outcome were collected and analyzed retrospectively.

RESULTS

Significantly higher SIRS and APACHEII scores were confirmed in the rAT group than the pAT group. The initial dose of AT was significantly higher in the rAT group than in the pAT group. ATIII values before and after initial supplementation and during their ten-day clinical course were statistically similar between two groups. During the same period, 10 bleeding adverse events were found and there was no significant difference between both groups. Significantly more cases of the rAT group were administered with recombinant thrombomodulin concomitantly than those of the pAT group. Despite significantly more severe patients in rAT group, the clinical outcomes were the same in each group.

CONCLUSIONS

Compared with pAT, the supplementation of rAT indicates clinical effectiveness without increasing the risk of bleeding complications in adult DIC patients with low AT activity.

Anticoagulant Therapy in Sepsis. The Importance of Timing

Sepsis associated coagulopathy is due to the inflammation-induced activation of coagulation pathways concomitant with dysfunction of anticoagulant and fibrinolytic systems, leading to different degrees of haemostasis dysregulation. This response is initially beneficial, contributing to antimicrobial defence, but when control is lost coagulation activation leads to widespread microvascular thrombosis and subsequent organ failure. Large clinical trials of sepsis-related anticoagulant therapies failed to show survival benefits, but posthoc analysis of databases and several smaller studies showed beneficial effects of anticoagulants in subgroups of patients with early sepsis-induced disseminated intravascular coagulation. A reasonable explanation could be the difference in timing of anticoagulant therapy and patient heterogeneity associated with large trials. Proper selection of patients and adequate timing are required for treatment to be successful. The time when coagulation activation changes from advantageous to detrimental represents the right moment for the administration of coagulation-targeted therapy. In this way, the defence function of the haemostatic system is preserved, and the harmful effects of overwhelming coagulation activation are avoided.

Revision of the Japanese Association for Acute Medicine (JAAM) disseminated intravascular coagulation (DIC) diagnostic criteria using antithrombin activity

Background

With advances in the treatment of sepsis, the systemic inflammatory response syndrome (SIRS) has been losing its prognostic power. Since the SIRS category is no longer used for the diagnosis of sepsis, the disseminated intravascular coagulation (DIC) diagnostic criteria released by Japanese Association for Acute Medicine (JAAM) should be modified. Thus, the purpose of this study was to examine the appropriateness of replacing the SIRS score with antithrombin activity in JAAM-DIC diagnostic criteria.

Methods

We analyzed data from 819 septic patients who had received recombinant thrombomodulin. The relationships between the 28-day mortality rate and baseline laboratory and clinical parameters were examined using univariate and multivariate analyses, and the impact of replacing the SIRS criteria with antithrombin activity was evaluated.

Results

The SIRS score, prothrombin time ratio, and antithrombin activity were associated with the 28-day mortality rate (P values = 0.013, 0.018, and 0.003, respectively, by multivariate analysis). A modified version of the JAAM-DIC diagnostic criteria using an antithrombin activity <70 % was capable of diagnosing the identical number (n = 706) and a similar severity of patients (mortality, 34.6 % versus 34.8 %).

Conclusion

Since anticoagulant therapy is expected to be more effective in patients with more severe coagulation disorders, the modified version of the JAAM-DIC diagnostic criteria might be useful for discriminating patients with sepsis who are good candidates for anticoagulant therapy.

Antithrombin supplementation and risk of bleeding in patients with sepsis-associated disseminated intravascular coagulation

INTRODUCTION

Although antithrombin is commonly used for the treatment of sepsis-associated disseminated intravascular coagulation (DIC) in Japan, the factors influencing the incidence of bleeding complications have not been sufficiently studied. The purpose of this survey was to identify the factors that predict clinically relevant bleeding in patients receiving antithrombin for DIC.

METHODS

We analyzed data from 1026 sepsis-associated DIC patients with a baseline antithrombin activity ≤70% who underwent antithrombin supplementation at two dosages (1500IU/day or 3000IU/day) for three consecutive days. The patients' demographic characteristics, parameters before and after the treatment, and co-administered anticoagulants were analyzed in relation to the bleeding events.

RESULTS

Overall, 55 patients (5.36%) experienced bleeding events (major bleeding: 1.75%). Logistic regression analysis revealed that sustained DIC>7days was significantly associated with bleeding (odds ratio: 2.761, P=0.001). In contrast, the higher dose of antithrombin or the co-administration of recombinant thrombomodulin or heparins were not associated with bleeding events.

CONCLUSION

A higher dose of antithrombin or the concomitant use of other anticoagulants were not associated with bleeding events. On the other hand, sustained DIC lasting more than one week was associated with an increased risk of bleeding in patients with sepsis-associated DIC.

Disseminated intravascular coagulation - new pathophysiological concepts and impact on management

INTRODUCTION

Disseminated intravascular coagulation (DIC) is an intermediary mechanism of disease which develops secondary to many causes including sepsis, trauma and malignancies. This review attempts to summarise the new pathophysiological developments and the impact they have on the current and future management of DIC.

AREAS COVERED

Several publications detailing the pathophysiology of DIC and the clinical management were identified using a pubmed search. Expert commentary: In recent years, on the initiatives of the international society of thrombosis and haemostasis, important advances have been made on the diagnostic aspect of DIC. In addition, several researchers have focused on the pathophysiology of the condition which is likely to provide better diagnostic markers and targeted therapy. However, some confusion still exists in the definition and management of DIC since various specialists understands the mechanisms involved in DIC from different perspectives.

Disseminated Intravascular Coagulation

Anesthesiologists may encounter patients with disseminated intravascular coagulation, a potential complication of severe sepsis or major trauma. This practical guide discusses the clinical approach, laboratory diagnosis, and current management of this condition.

Efficacy and Bleeding Risk of Antithrombin Supplementation in Patients With Septic Disseminated Intravascular Coagulation: A Third Survey

INTRODUCTION

Although recent studies have reported the efficacy of antithrombin (AT) supplementation for sepsis-associated disseminated intravascular coagulation (DIC), the factors that influence AT's effect have not been sufficiently studied. The purpose of this survey was to identify factors that modulate the effects and the adverse effects of AT.

METHODS

We performed a multi-institutional survey. The data from 159 patients with septic DIC with AT ≤70% and who had undergone AT supplementation were analyzed. The patients' demographic characteristics, including the infection site, baseline sepsis-related organ failure assessment (SOFA) score, baseline DIC score, and baseline AT activity, were analyzed in relation to the 28-day mortality. Bleeding-related adverse events were also examined.

RESULTS

Overall, 116 patients survived and 43 did not (28-day mortality: 27.0%). A logistic regression analysis revealed that the baseline SOFA score (odds ratio [OR]: 0.816, P = .001), coadministration of recombinant thrombomodulin (rTM; OR: 3.989, P = .006), and respiratory tract infection (OR: 0.129, P = .000) were significantly associated with the survival. Survivors exhibited a higher peak AT activity than nonsurvivors (85.1% vs 65.0%, P = .027). Bleeding events were observed in 4.13% (major bleeding: 1.65%) of the patients, and the coadministration of rTM did not increase the risk of bleeding (with rTM: 4.11% vs without rTM: 4.17%). Heparin was concomitantly used in 22 (18.2%) cases, and its use nonsignificantly increased the bleeding risk (with heparins: 9.09% vs without heparins: 3.03%; P = .224).

CONCLUSION

The coadministration of rTM may improve survival without increasing the risk of bleeding in patients with sepsis-associated DIC treated with AT.

Antithrombin: anti-inflammatory properties and clinical applications

Many humoral and cellular components participate in bidirectional communication between the coagulation and inflammation pathways. Natural anticoagulant proteins, including antithrombin (AT), tissue factor pathway inhibitor, and protein C, suppress proinflammatory mediators. Conversely, inflammation blunts anticoagulant activity and, when uncontrolled, promotes systemic inflammation-induced coagulation, such as those that occur in disseminated intravascular coagulation and severe sepsis. This review discusses the mechanisms of action and clinical use of AT concentrate in critically ill patients and in the settings of perioperative anticoagulation management for surgery and obstetrics. AT is a serine protease inhibitor with broad anticoagulant activity and potent anti-inflammatory properties. In clinical conditions associated with hereditary or acquired AT deficiency, administration of AT concentrate has been shown to restore proper haemostasis and attenuate inflammation. Of note, AT modulates inflammatory responses not only by inhibiting thrombin and other clotting factors that induce cytokine activity and leukocyte-endothelial cell interaction, but also by coagulation-independent effects, including direct interaction with cellular mediators of inflammation. An increasing body of evidence suggests that AT concentrate may be a potential therapeutic agent in certain clinical settings associated with inflammation. In addition to the well-known anticoagulation properties of AT for the treatment of hereditary AT deficiency, AT also possesses noteworthy anti-inflammatory properties that could be valuable in treating acquired AT deficiency, which often result in thrombotic states associated with an inflammatory component.

Present and future of anticoagulant therapy using antithrombin and thrombomodulin for sepsis-associated disseminated intravascular coagulation: a perspective from Japan

In sepsis, the coagulation system is often systemically activated in combination with the simultaneous impairment of fibrinolysis and anticoagulant systems. Since this hypercoagulable state often leads to disseminated intravascular coagulation (DIC), an independent predictor of mortality in critically ill patients, the appropriate management of DIC itself is a crucial part of treatment strategies for severe sepsis. In this context, the Japanese Association of Acute Medicine (JAAM) scoring system for DIC has been proposed as a valid test for diagnosing DIC; this system is also expected to aid in devising specifically tailored management strategies. Anticoagulant therapy is commonly given to septic patients with DIC as part of the standard care in Japan. More recently, antithrombin concentrate and recombinant thrombomodulin have become the two major anticoagulant agents of choice. In relation to the use of antithrombin, recent studies have indicated that the recovery of antithrombin activity to within the normal range (>70%) is necessary if supplementation therapy is to provide a favorable outcome. Recombinant thrombomodulin is slightly more controversial, with favorable results being greater among severe cases of DIC. In the present review, we summarize recent clinical advances in anticoagulant therapy for sepsis-associated DIC.

A single-dose of oral nattokinase potentiates thrombolysis and anti-coagulation profiles

Our aim was to determine the quantitative effects of a single-dose of Nattokinase (NK) administration on coagulation/fibrinolysis parameters comprehensively in healthy male subjects. A double-blind, placebo-controlled cross-over NK intervention study was carried out in 12 healthy young males. Following the baseline blood draw, each subject was randomized to receive either a single-dose of 2,000 FU NK (NSK-SD, Japan Bio Science Laboratory Co., Ltd) or placebo with subsequent cross-over of the groups. Subjects donated blood samples at 2, 4, 6 and 8 hours following administration for analysis of coagulation/fibrinolysis parameters. As a result, D-dimer concentrations at 6, and 8 hours, and blood fibrin/fibrinogen degradation products at 4 hours after NK administration elevated significantly (p < 0.05, respectively). Factor VIII activity declined at 4 and 6 hours (p < 0.05, respectively), blood antithrombin concentration was higher at 2 and 4 hours (p < 0.05, respectively), and the activated partial thromboplastin time prolonged significantly at 2 and 4 hours following NK administration (p < 0.05 and p < 0.01, respectively). All the changes, however, were within the normal range. In conclusion, thus, a single-dose of NK administration appears enhancing fibrinolysis and anti-coagulation via several different pathways simultaneously.