Hemostatic Mechanism Research Articles

Physiological parameters of hemostasis in weakened newborn piglets and calves with gamavit injection

The deployment of the first stages of ontogenesis in all types of productive animals is determined by the change in hemostatic and rheological mechanisms. The status of these parameters strongly influences the deployment of heredity of an organism of any animal. The normal operation of the hemostasis during the neonatal strongly determines the rheological properties of blood, and therefore metabolism in the organs of young animals. Phase of neonatal calves and piglets is a serious stage of their development. Therein have the characteristic of hemostatic processes. The authors determined that during the first or second day of life in physically impaired calves and piglets develop physiologically unfavorable changes in haemostatic parameters, platelets, blood vessels and blood clotting. Emerging changes adversely affect the operation of their bodies and lead to total exclusion. The use of the drug gamavit enhances the weakened condition of newborn calves and piglets functionally acceptable reduce the activity of platelets and clotting of blood in a functionally justified the growth of the hemostatic capabilities of the vessels. It can be argued that injections of gamavit negate the existing dysfunction in hemostasis in physically weakened calves and piglets during the neonatal phase, increasing their adaptation and stimulating further growth and development of animals.

The Need for a Physiological Classification of Hemorrhagic Shock.

Classifications mean to conceptualize in a cluster and rapidly summarize the assessment and management of a clinical scenario. In the specific case of a hemorrhagic shock (HS), a classification should serve the purpose of allowing a rapid clinical assessment of the shock level and the earliest or right timing of source control, possibly also on whether to apply damage control surgery (DCS) strategy or not. ATLS® classification of HS is not sensitive and specific enough to help decision-making in reference to the timing of management, based only on the amount of blood loss that may be or may not rightly estimated, for example, blood loss on the floor in penetrating injuries before theatre. Moreover, it focuses also on other parameters, which are taken singularly, instead of the individual generalized physiological response to hemorrhage, which is the core by definition of the derangement we call “shock.” It is unhelpful, difficult, and impractical to apply as well. A new classification, which may well be called as the “physiological HS classification” or “therapeutic HS classification,” was proposed since 2010, following the new developments on microcirculation and an already going-on sensible praxis among some trauma surgeons. It bases on some physiological considerations such as the significance of fluid-blood resistant hypotension, body natural hemostatic mechanisms, the right definition of shock, and the relevance that hemorrhage-triggered ischemia-reperfusion toxemia and systemic inflammatory response have in critical illness scenarios as secondary insults from ischemia, which is what we mean to prevented with DCS. The key factor remains the persistence of hypotension, following fluid challenge.

Gellable silk fibroin-polyethylene sponge for hemostasis

Traditional haemostatic materials generally have slow hemostasis rate and poor biocompatibility. This paper reports on the haemostatic properties and mechanism of silk fibroin (SF). SF-PEG sponge that could be solubilised and changed to gel form by blood was fabricated through mixing SF and polyethylene glycol (PEG, 1500 Da) followed by lyophilisation of the mixed solution. SF-PEG sponge, together with control samples of SF sponge (no PEG) and a commercially available haemostatic material, gelatine sponge, were subjected to the hemostasis tests using a liver trauma model of rabbit. The results showed that SF was superior to gelatine sponge in hemostasis time (136.17 ± 62.27 s and 249.83 ± 29.18 s) and blood loss (2.16 ± 1.27 g vs. 4.97 ± 1.44 g). Furthermore, in vitro experiments indicated SF-PEG sol-gel transition promoted platelet adhesion and aggregation, as well as platelet-fibrinogen interaction. Therefore, except for the physical blocking of bleeding port due to PEG-induced SF fast gelation, SF might also have an impact on blood coagulation process, a phenomenon that has not been reported before. In conclusion, SF is a new type of haemostatic material that might be able to meet the requirements of speed, efficiency and biosafety in a variety of clinical applications.

The role of the red blood cell and platelet in the evolution of mammalian and avian endothermy.

This review presents evidence to support the hypothesis that the reduced O2 during the Permian/Triassic period was the impetus for the evolutionary selection of endothermic animals. The evolution of smaller red blood cells with greater surface areas along with increased: capillary density, capillary surface area, hematocrits, blood pressure, blood flow rates, and shear rates were critical for efficient gas exchange in endothermy. The evolution of the four-chambered mammalian/avian heart allowed for low pulmonary and high systemic blood pressure. It is proposed that hypoxia-induced angiogenesis led to increased vascularization in endothermic animals. The increased blood pressure, flow rates, and shear forces likely required changes in hemostatic mechanisms that were met in mammals by the evolution of anucleate platelets. The evolution of mammals and birds occurred in a parallel fashion with further genetic changes to anucleate RBCs/platelets occurring in mammals. Although it is possible that the evolution of endothermy in birds and mammals occurred as two independent events, it is more likely that a common ancestor developed genetic mutations that laid down the road map for parallel alterations of their cardiovascular system in response to environmental pressures. Model systems to support the proposed changes from ectotherm to endotherm were developed from published data. The evolutionary development of endothermy occurred over millions of years with a continuum of genetic alterations that involved skeletal, soft tissue, cardiovascular macrochanges along with numerous molecular alterations. Genetic signals and potential regulators for the evolutionary changes of endothermic blood cells from their bipotential stem cells are also proposed.

Association of Bleeding Time and Clotting Time with ABO Blood Groups Among Healthy Adults

Background
 Haemostasis is the stoppage of bleeding. Bleeding time (BT) and Clotting time (CT) assess the integrity of haemostatic mechanisms. Assessment of Hematological parameters like bleeding time, clotting time and blood grouping are a very important before initiating any surgical procedure. Blood group has clinical importance in transfusion medicine and medico legal cases. Some studies have showed epistaxis and thrombosis found in O blood group individuals. Earlier studies showed the conflicting results regarding association of blood group with clotting time and bleeding time.
 Objectives
 The aim of the study was to assess the distribution of ABO blood groups in males and females with age group of 17-21yrs and determination of BT and CT among males & females. To analyze the relationship between the blood groups, BT and CT.
 Method
 The study was conducted in Department of Physiology, Mamata Medical College. The study included 205 healthy volunteers of age group between 18-21years. Blood grouping, bleeding time and clotting time were determined. Statistical analysis done by un paired t test for calculating gender wise CT and BT and ANOVA and Post Hoc test for assessing relationship between BT, CT and blood groups.
 Results
 Our study results showed that blood group O was predominant in both males and females. Clotting time and bleeding time is statistically higher in females compared to males. Results showed clotting time is statistically significant (0.011) only between group A & group O, with higher value in group O but not the bleeding time.
 Conclusion
 Blood group O was the most common group. BT and CT were higher in females than males. May be due to high estrogen and lower fibrinogen levels in females. CT and BT maximum in blood group O due to more activation of von Willebrand's Factor.

Hemostasis, Hematoma Expansion, and Outcomes after Intracerebral Hemorrhage

Background: Intracerebral hemorrhage (ICH) is a serious complication of stroke with significant morbidity and mortality. Intracerebral bleeding and hematoma expansion (HE) cause displacement and damage to brain tissue leading to disability and death. An important approach to improve patient outcomes from ICH is to prevent HE. Our ability to improve patient outcomes depends on our ability to recognize HE and the associated hemostatic mechanisms. This study is designed to evaluate biomarkers of platelet function, coagulation and fibrinolysis and relate these biomarkers to statistically powerful estimates of HE and patient outcomes. Study Design and Methods: Patients with acute ICH within the first 12 hours of the onset of symptoms will be studied to identify hemostasis biomarkers which may predict hematoma expansion. Major inclusion criteria: Spontaneous ICH within 12 hours of symptom onset; age at least 21 years; consent from the patient or a representative. Exclusion criteria: hereditary hemostasis disorders, history of malignancy, vascular malformation suspected or on imaging, sepsis, comorbid condition that is likely to be disabling or fatal, hemoglobin less than 7.5 g/dL, pregnancy. Statistical methods: We will test the hypothesis that each hemostasis biomarker predicts HE by using Mann-Whitney U (for non-parametric) or ANOVA (for normally distributed results). We will set P<0.01 given the multiple biomarkers to be assessed. The 80% power using a Mann-Whitney U to test the hypothesis that the distributions of HE are 3 mL different would require 147 patients (calculations made with PASS v.12, NCSS Inc., Kaysville, UT). Machine learning techniques will be applied to hemostasis biomarkers to predict the modified Rankin score (mRS), T Scores of HRQoL, and T Scores of NIH Toolbox outcomes. Precision-recall and receiver operating characteristic (ROC) curves will be constructed, and area under the curve will be compared. Biomarker selection or companion diagnostics: This study will measure platelet activity, coagulation activation and fibrinolysis in patients with acute onset (less than 12 hours) intracerebral hemorrhage ICH to determine hemostatic mechanisms of hematoma expansion. Global activity of platelets, coagulation factors and fibrinolysis activity are measured by thromboelastogram (TEG) and rotational thromboelastometry (ROTEM) assays. Platelet activity is also measured with Platelet Function assay, PFA-100, Platelet Aspirin Assay and the Platelet P2Y12 Assay. Coagulation activation is measured by Tissue Factor antigen and activity and Thrombin Generation Assay. Fibrinolysis is assayed by Plasmin/antiplasmin (PAP) complex, Fibrinogen, D-Dimer and PAI-1 antigen and activity. Study treatment, endpoints: The hemostatic parameters and hematoma expansion are compared to patient outcomes measured by the mRS and health related quality of life (HRQoL) and objective outcomes measures from the NIH toolbox to determine the relationship to patient outcomes. The mRS is a standard outcome measure for patients with ICH. The NIH developed and validated HRQoL measures Patient-Reported Outcomes Measurement Information System (PROMIS), Quality of Life in Neurological Disorders (Neuro-QoL), and objective function NIH Toolbox are the most sensitive and provide statistically powerful estimates of patient outcomes in survivors of ICH. Future Directions: This study is designed to identify hemostatic factor abnormalities and mechanisms of ICH hematoma expansion treatable with targeted therapies (e.g., desmopressin to counteract aspirin effect or fibrinolysis inhibitors). Machine learning algorithms will be employed for predicting patient outcomes after ICH and may illuminate when HE is most impactful and determine specific therapies which improve patient outcomes. This study is funded by a National Institutes of Health (NIH)/ The Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD) grant ID: SP0049593; R01 NS110779. Disclosures Naidech: NIH: Other: NS110779-Grant.

Research on hemostatic effect and mechanism of carbonized Scutellariae Radix on rats of uterine bleeding

The aim of this paper was to investigate the hemostatic effect and mechanism of carbonized Scutellariae Radix on uterine bleeding in the rats caused by early pregnancy termination. Eight unpregnant female rats were selected as normal group. Forty female rats conceived on the same day received mifepristone(11. 4 mg·kg-1) and misoprostol(125 μg·kg-1) to induce model of incomplete abortion in early pregnancy. Abortion models were randomly divided into model group,carbonized Scutellariae Radix water extract low dose group(0. 55 g·kg-1),medium group(1. 10 g·kg-1),high dose group(2. 20 g·kg-1) and positive control group(0. 45 g·kg-1).The uterine bleeding volume was detected by ultraviolet spectrophotometry. The pathological changes of endometrium were detected by HE(hematixylin-eosin) staining. The levels of interleukin(IL-1β),IL-6 and tumor necrosis factor(TNF-α) in the plasma of rats were determined by ELISA. The expression levels of IL-1β,IL-6 and TNF-α mRNA in the uterus of rats were determined by RT-PCR.The protein expression levels of VEGF,MMP-2 and MMP-9 were determined by Western blot. As compared with the normal group,the uterine bleeding volume and histopathological score were increased significantly; microvessel density of endometrial tissues was decreased significantly; the contents of TNF-α,IL-1β and the levels of TNF-α mRNA and IL-1β mRNA in the plasma were increased,while the content of IL-6 and level of IL-6 mRNA were decreased significantly. The protein expression levels of VEGF,MMP-2 and MMP-9 in the uterine tissues were also decreased. As compared with the model group,the uterine bleeding volume was decreased significantly in the carbonized Scutellariae Radix medium dose and high dose groups; endometrial repair was promoted,and the microvessel density of endometrial tissues was increased significantly; the contents of IL-1β and TNF-α in the plasma of rats were decreased significantly,while the content of IL-6 in the plasma of rats was increased significantly; the expression levels of IL-1β and TNF-α mRNA in the uterus of rats were decreased and the expression level of IL-6 mRNA showed an increase; the protein expressions of VEGF,MMP-2 and MMP-9 were decreased significantly in carbonized Scutellariae Radix medium and high dose groups. In conclusion,carbonized Scutellariae Radix showed good hemostatic effect,and its mechanism may be related to the repair of endometrium and inhibition of inflammatory reaction.

Effect of poor glycaemic control on plasma levels and activity of protein C, protein S, and antithrombin III in type 2 diabetes mellitus.

BackgroundType 2 diabetes mellitus (T2DM) patients are predisposed to several diabetes-related complications. Dysregulation of the haemostatic mechanisms have been implicated. There are however no current studies assessing the levels and activity of protein C (PC), protein S (PS), and antithrombin III (AT III), which are essential in haemostatic regulation, in a single cohort of T2DM patients. This study evaluated the effect of poorly-managed T2DM on the levels and activity of PC, PS, and AT III.MethodsThis cross-sectional study was conducted at the Diabetes Clinic, Cocoa Clinic in Kumasi, Ghana. A total of 242 T2DM patients, comprising 152 patients with poorly-managed diabetes and 90 well-managed diabetes patients, were recruited for the study. Fasting blood glucose, liver function tests and lipid profile were performed for each respondent. Glycated haemoglobin (HbA1c) was estimated by turbidimetric inhibition immunoassay. The levels and activity of PC, PS and AT III were measured by solid phase sandwich ELISA method.ResultsThere was a negative correlation between HbA1c and the levels and activity of PC, PS and AT III. The levels and activity of PC [(5.78 vs 4.64 μg/ml, p<0.0001) and (42.22 vs 36.21 U/ml, p = 0.01) respectively], PS [(22.55 vs 20.29 μg/ml, p = 0.010) and (235.94 vs 211.67 U/ml, p<0.0001) respectively] and AT III [(16.28 vs 14.41μg/ml, p<0.0001) and (176.01 vs 160.09 U/ml, p = 0.03) respectively] were significantly increased in patients with well-managed T2DM compared to the poorly-managed diabetes patients. Likewise, the levels and activity of PC, PS, and AT III was higher among T2DM patients using statins than patients who were statin-naïve. Among patients with well-managed T2DM, those who were on statins had significantly higher levels and activities of PC, PS, and AT III compared to well-managed T2DM patients not on statins. However, there no statistically significant differences between the level and activity of PC, PS, and AT III among poorly-managed T2DM patients with respect to statin status.ConclusionPoorly-managed type 2 diabetes mellitus is associated with reduced levels and activity of PC, PS and AT III compared to well-managed T2DM. Though use of statins may improve the levels and activity of the PC, PS and AT III in T2DM, their effect is limited in the presence of poorly-controlled T2DM. Proper management of diabetes is essential to reduce the likelihood of thrombotic events among T2DM patients.

Evaluation of some clotting factors (FI, FVII, FVIII and FIX) and estradiol hormone deficiency in menopausal women

Women are complained from several physiological and biochemical disturbances when they become aged and loss adequate amount of estradiol hormone secreted from ovarian follicles. The present study conduct to evaluate the concentration of some available clotting factors and feminizing hormone (estradiol hormone) in menopausal women. A total number of participants postmenopausal women was sixty (60) women and their ages were 50 to 69 years old and fifteen (15) women their ages premenopausal women (control group) that they have normal menstruation cycle and whose ages ranged between 20 – 25 years old. The aging women (menopause) were subdivided according to their ages periods in to four groups, the first group (50 – 54 years), second group (55 – 59years), third group (60- 64 years), and fourth group (65 –69 years). Values of estradiol hormone recorded a significant drop in all groups of postmenopausal women in matching with counter parts of premenopausal women. About prothrombin time (PT), its results showed a remarkable elevation (p<0.05) in all groups of menopausal women when compared with control group. Values of intrinsic pathway test (activated partial thromboplastin time) indicated remarkable increase (p<0.05) in all tested groups (menopausal women) compared to control group. In regard to clotting factors, levels of fibrinogen (FI) concentrations did significantly progressive elevated (p<0.05) in all postmenopausal women groups in matching with those of control group. Also, concentrations of stable factor (VII) were significantly increased (p<0.05), whereas antihemophilic factors (VIII) and Christmas factor (IX) pointed out a significant progressive fall (p<0.05) of aging women in a comparison with premenopausal women. In conclusion, deficiency of estradiol hormone in postmenopausal women appears associated with fluctuation of clotting factor concentrations and these disturbances can give an indicator that estradiol hormone maintain hemostatic mechanism to prevent risk of cardio-vascular problems.

Coagulation Profile in neonates with perinatal asphyxia

Background: Perinatal Asphyxia refers to a condition during the first and second stage of labour in which impaired gas exchange leads to fetal acidosis, hypoxemia and hypercarbia. It accounts for about 23 per cent of the four million newborn deaths worldwide.Methods: To estimate the magnitude of coagulation derangement in babies who suffered birth asphyxia and compare it with non-asphyxiated controls.Results: There were 61.9% and 64 % males in both the groups outnumbering females suggesting that the health care seeking behavior for male children is more than for their female counterparts. Birth weight and mode of delivery are comparable in both the groups. PT and APTT were significantly higher in the asphyxiated babies than in their respective control group. It may be noted , however, that PT and APTT values were higher in the control group also, when compared with the reference values. This may indicate that the hemostatic mechanisms are already compromised in the newborns and perinatal asphyxia further augment the situation tilting it in favour of bleeding. Thrombocytopenia is observed in the asphyxiated group which may be due to placental insufficiency. Severe bleeding is significant in asphyxiated group as compared to the control.Conclusion: Dyscoagulation should be considered in all asphyxiated babies, and they may present with clinically significant bleeding, which may require fresh frozen plasma to restore and maintain their coagulation status.

Peptide-immobilized starch/PEG sponge with rapid shape recovery and dual-function for both uncontrolled and noncompressible hemorrhage

It is challenging for traditional hemostatic sponges to meet the clinic demand for both uncontrolled and noncompressible hemorrhage. With the aim to develop a rapid shape recovery material with both active and passive hemostatic performance, a dual-functional hemostatic sponge (TRAP-Sp) with a macroporous structure and good mechanical properties for controlling massive and noncompressible hemorrhage was prepared by chemically immobilizing thrombin-receptor-agonist-peptide (TRAP) onto a starch/polyethylene glycol (PEG) sponge. The TRAP2-Sp1 showed the best hemostatic performance among all samples in both rat artery uncontrollable hemorrhage and liver defect noncompressible hemorrhage models. When analyzing the hemostatic mechanism of TRAP-Sp, the high water absorption capacity of the sponge contributed to absorbing plasma, concentrating blood cells, and enhancing blood coagulation. After absorbing water, the shape-fixed TRAP-Sp with sufficient mechanical strength and high resilience can rapidly expand and apply pressure to the wound. TRAP immobilized on the sponge could activate the adhered platelets in an active pathway. Additionally, evaluation of cytotoxicity, hemolysis, and histology further highlighted the adequate biocompatibility of TRAP-Sp. With excellent hemostatic performance and biosafety, this sponge could be a potential candidate as a topical hemostatic agent for uncontrolled and noncompressible hemorrhage. Statement of SignificanceThere is a need for innovative hemostatic materials for both uncontrolled and noncompressible hemorrhage. This manuscript describes a rapid shape recovery hemostatic sponge with both active and passive hemostatic performances synthesized by foaming technique, cross-linking reaction, and chemical immobilization of thrombin-receptor-agonist-peptide (TRAP). On contact with blood, the shape-fixed sponge can not only rapidly recover its original shape and concentrate platelets and RBCs but also activate the adhered platelets efficiently. The dual-functional sponge has excellent hemostatic efficacy in rat femoral artery hemorrhage and can control noncompressible hemorrhage in penetrating liver wound. Thus, we believe that this sponge could be a potential candidate as a topical hemostatic agent for uncontrolled and noncompressible hemorrhage.

Transient or extended reversal of apixaban anticoagulation by andexanet alfa is equally effective in a porcine polytrauma model

BackgroundAndexanet alfa (andexanet) reverses the anticoagulant effects of factor Xa inhibitors, but it has not been assessed in clinical studies for apixaban reversal in trauma. This study evaluated andexanet for reversing apixaban anticoagulation in a porcine polytrauma model. MethodsOral apixaban (20 mg q.d., n=21) or placebo (n=7; sham group) was administered to male pigs for 4 days before blunt liver injury and bi-lateral femur fracture. After trauma, animals were randomised 1:1:1 to a single andexanet bolus (1000 mg), a bolus (1000 mg) plus infusion (1200 mg over 2 h), or vehicle (control). Haemodynamic and coagulation variables were monitored for 5 h or until death. The primary endpoint was blood loss. ResultsMean blood loss in sham animals was 472 (standard deviation, 58) ml 12 min after injury and 658 (98) ml at 300 min, with 100% survival. Anticoagulation with apixaban significantly increased blood loss 12 min after injury [888 (133) ml, P<0.01]. Controls exhibited total blood loss of 3403 (766) ml, with 100% mortality. Andexanet bolus or bolus plus infusion significantly reduced blood loss to 1264 (205) and 1202 (95) ml, respectively), and increased survival to 100%. Haemodynamic parameters and markers of shock recovered to pre-trauma levels in andexanet-treated animals. ConclusionAndexanet effectively reversed apixaban anticoagulation and reduced blood loss induced by severe trauma. Andexanet bolus alone had a similar impact on survival and blood loss as bolus plus infusion. Therefore, a 2 h andexanet infusion after the bolus may not be necessary to restore normal haemostatic mechanisms.

Calcium ion–exchange cross-linked porous starch microparticles with improved hemostatic properties

Starch hemostatic agents have been clinically used in surgical hemostasis in recent years. Calcium ion (Ca2+)-exchange cross-linked porous starch microparticles (Ca2+CPSMs) were prepared as a new hemostatic agent to enhance the hemostatic efficacy. A series of Ca2+CPSMs with varying Ca2+ contents were prepared and characterized by Fourier-transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), scanning electron microscope (SEM), and ion content analysis. The XPS and FT-IR results indicated that the surface of Ca2+CPSMs was modified by Ca2+, which might form coordination bonds with oxygen atoms of starch molecules. Ca2+CPSMs revealed a porous surface structure and a lower crystallinity degree according to SEM and XRD, which facilitated the phosphate buffer saline (PBS) uptake rate and enzymatic degradation in vitro. The fast release of Ca2+ from Ca2+CPSMs accelerated the whole blood clotting rate, shortened the activated partial thromboplastin time, and promoted platelet adhesion. The physical hemostatic mechanism benefited from the rapid PBS uptake capacity and porous surface structure of Ca2+CPSMs, in addition to the chemical activation of coagulation process by Ca2+, thus achieving a significant hemorrhage control in the mouse tail amputation model.

Newly Identified HNP-F from Human Neutrophil Peptide-1 Promotes Hemostasis.

Activehemostatic agents can play a crucial role in saving patients' lives during surgery. Active hemostats have several advantages including utilization of natural blood coagulation and biocompatibility. Among them, although human neutrophil peptide-1 (HNP-1) has been previously reported with the hemostatic mechanism, which part of HNP-1 facilitates the hemostatic activity is not known. Here, a partial peptide (HNP-F) promoting hemostasis, originating from HNP-1, has been newly identified by the blood coagulation ability test. HNP-F shows the best hemostatic effect between the anterior half and posterior half of peptides. Moreover, microscopic images show platelet aggregation and an increase in the concentration of platelet factor 4, and the scanning electron microscope image of platelets support platelet activation by HNP-F. Thromboelastography indicates decreased clotting time and increased physical properties of blood clotting. Mouse liver experiments demonstrate improved hemostatic effect by treatment of peptide solution. Cell viability and hemolysis assays confirm the HNP-F's biosafety. It is hypothesized that the surface charge and structure of HNP-F could be favorable to interact with fibrinogen or thrombospondin-1. Collectively, because HNP-F as an active peptide hemostat has many advantages, it could be expected to become a potent hemostatic biomaterial, additive or pharmaceutical candidate for various hemostatic applications.

AGA Clinical Practice Update: Coagulation in Cirrhosis.

This expert review was commissioned and approved by the AGA Institute Clinical Practice Updates Committee and the AGA Governing Board to provide timely guidance on a topic of high clinical importance to the AGA membership. The intent is to evaluate the current data on mechanism of altered coagulation in patients with cirrhosis, provide guidance on the use of currently available testing of the coagulation cascade, and help practitioners use anticoagulation and pro-coagulants appropriately in patients with cirrhosis. This review is framed around the best practice points, which were derived from the most impactful publications in the area of coagulation in cirrhosis and agreed to by all authors. BEST PRACTICE ADVICE 1: Global tests of clot formation, such as rotational thromboelastometry, thromboelastography, sonorheometry, and thrombin generation, may eventually have a role in the evaluation of clotting in patients with cirrhosis, but currently lack validated target levels. BEST PRACTICE ADVICE 2: In general, clinicians should not routinely correct thrombocytopenia and coagulopathy before low-risk therapeutic paracentesis, thoracentesis, and routine upper endoscopy for variceal ligation in patients with hepatic synthetic dysfunction-induced coagulation abnormalities. BEST PRACTICE ADVICE 3: Blood products should be used sparingly because they increase portal pressure and carry a risk of transfusion-associated circulatory overload, transfusion-related acute lung injury, infection transmission, alloimmunization, and/or transfusion reactions. BEST PRACTICE ADVICE 4: The following transfusion thresholds for management of active bleeding or high-risk procedures may optimize clot formation in advanced liver disease: hematocrit ≥25%, platelet count >50,000, and fibrinogen >120 mg/dL. Commonly utilized thresholds for international normalized ratio correction are not supported by evidence. BEST PRACTICE ADVICE 5: Thrombopoietin agonists are a good alternative to platelet transfusion, but require time (about 10 days) to elevate platelet levels. BEST PRACTICE ADVICE 6: The large volume of fresh frozen plasma required to reach an arbitrary international normalized ratio target, limitations of the usual target, minimal effect on thrombin generation, and adverse effects on portal pressure limit the utility of this agent significantly. BEST PRACTICE ADVICE 7: The 4-factor prothrombin complex concentrate contains both pro- and anticoagulant factors that offer an attractive low-volume therapeutic to rebalance a disturbed hemostatic system. However, dosage is, in part, based on international normalized ratio, which is problematic in cirrhosis, and published experience in liver disease is limited. BEST PRACTICE ADVICE 8: Anti-fibrinolytic therapy may be considered in patients with persistent bleeding from mucosal oozing or puncture wound bleeding consistent with impaired clot integrity. Both ε-aminocaproic acid and tranexamic acid inhibit clot dissolution. Neither is believed to generate a hypercoagulable state, although both may exacerbate pre-existing thrombi. BEST PRACTICE ADVICE 9: Desmopressin releases von Willebrand factor as its primary hemostatic mechanism. As this factor is usually elevated in cirrhosis, the agent lacks a sound evidence-based foundation, but may be useful in patients with concomitant renal failure. BEST PRACTICE ADVICE 10: Systemic heparin infusion is recommended for symptomatic deep vein thrombosis and portal and mesenteric vein thrombosis, but there are unresolved issues regarding monitoring with both the anti-Xa assay and the partial thromboplastin time due to cirrhosis-related antithrombin deficiency (heparin cofactor). BEST PRACTICE ADVICE 11: Treatment of incidental portal and mesenteric vein thrombosis depends on estimated impact on transplantation surgical complexity vs risks of bleeding and falls. Therapy with low-molecular-weight heparin, vitamin K antagonists, and direct-acting anticoagulants improve portal vein repermeation vs observation alone. BEST PRACTICE ADVICE 12: Direct-acting anticoagulants, such as the factor Xa and thrombin inhibitors, are relatively safe and effective in stable cirrhotic patients, but are in need of further study in patients with more advanced liver disease.

A highly efficient, in situ wet-adhesive dextran derivative sponge for rapid hemostasis

Uncontrolled hemorrhage is closely related to the high risk of death. However, local hemostats still have various defects and side effects. Herein, an aldehyde dextran (PDA) sponge with proper absorption and adhesion properties is developed for hemorrhage control. PDA sponge with pore size of ∼30–50 μm fabricated by lyophilization not only absorbs blood quickly (47.7 g/g), but also possesses strong tissue adhesion (∼100 kPa). PDA sponge with low cytotoxicity and hemolysis achieves effective hemostasis and remarkable blood loss reduction in the ear vein, femoral artery and liver injuries of rabbit models. Furthermore, the exploration of hemostatic mechanisms related to tissue, blood, plasma, cells and coagulation system indicates that PDA sponge can significantly accelerate coagulation by rapid wound block, fast cells aggregation and initiation, and high coagulation factors concentration, instead of by the coagulation cascade activation. Importantly, this hemostat exhibits excellent biodegradability and nearly no skin irritation. Overall, the biodegradable and tissue adhesive PDA sponge will be a promising quick-hemostatic dressing for uncontrollable hemorrhage.

A Network Pharmacology Approach Used to Estimate the Active Ingredients of Moutan Cortex Charcoal and the Potential Targets in Hemorrhagic Diseases.

Moutan Cortex charcoal has been used to ameliorate blood heat symptoms and treat pathologic hemorrhage down the ages. Although well known as an agent with the effect of astringency and hemostasis, its active ingredients and action mechanism remain unclear. In the present study, molecular docking technology was employed to screen the potential hemostatic compounds in Moutan Cortex charcoal and their target proteins. Protein-protein-interaction (PPI) analysis was performed to explain the functions and enrichment pathways of the target proteins. The results showed that a total of 25 compounds were estimated as active constituents targeting multiple proteins related to hemostatic diseases, including 5 proteins (SERPINC1, FVIII, FX, FII and FXII) that were considered as the key targets. Then the drug-target (D-T) network was constructed to analyze the underlying hemostatic mechanism of Moutan Cortex charcoal, followed by a hierarchical cluster analysis (HCA) for compounds clustering, and a coagulation screening test for compound verification on their coagulation activities, with the results indicating that M15 (5-Tetradecenoic acid) and M31 (1-Monolinolein) might be the key compounds contributing to the hemostasis effect of Moutan Cortex charcoal by involving in the pathways related to complement, coagulation cascades and the platelet activation, particularly by activating FVIII, FX, FII and FXII and inhibiting SERPINC1. This study has demonstrated that Moutan Cortex charcoal may work as a hemostatic through the interaction between multiple-compounds and multiple-proteins, which provides the basis for further researches on the hemostasis mechanism of Moutan Cortex charcoal.

Abstract WP169: Coated-platelets and Tumor Necrosis Factor Alpha Predict TIA/stroke at Twenty-one Months in Asymptomatic Carotid Stenosis

Background: The clinical spectrum of carotid atherosclerosis is well characterized, but the events leading to plaque instability and stroke are less understood. Evidence suggests that platelets serve as an interface among hemostasis, inflammation, and atherosclerosis. Coated-platelets, a subset of platelets with high procoagulant potential, are increased in asymptomatic carotid stenosis patients at high risk for stroke or TIA. We now examine the impact of other soluble mediators of inflammation, cell adhesion, angiogenesis and coagulation on the association between coated-platelets and TIA/stroke in asymptomatic carotid stenosis. Methods: Consecutive asymptomatic patients with ≥50% carotid stenosis were enrolled. Coated-platelet levels were assayed and plasma was obtained for measurement of 58 biomarkers. Patients were followed at 6-month intervals for intensive vascular risk reduction. Those with signs or symptoms of TIA/stroke underwent either brain CT or MRI. Rank order correlations between inflammatory marker concentrations, coated-platelet levels and TIA/stroke were determined using the Spearman correlation coefficient. Variables associated with TIA/stroke (p&lt;0.15) were included in multivariate analysis. Results: We enrolled 117 patients (97% male, average age 71, 94% on statins, 96% on antiplatelets, and 33% currently smoking, average HgA1c 6.6% and average LDL 86 mg/dL). There were 6 strokes and 2 TIA’s ipsilateral to carotid stenosis during a mean 21.3 ± 6.7 months of follow-up (incidence of 3.89/100 person-years). Stepwise logistic regression identified TNF alpha (OR=11.1, p=0.0300) and coated-platelet group (OR=14.1, p=0.0167) as predictors of TIA/stroke ipsilateral to stenosis. Cox Proportional Hazard analysis yielded a TIA/stroke HR of 11.8 for the high coated-platelet group (95% CI 1.4, 96.1, p=0.0215) and 8.0 (95% CI 0.97, 66.3, p=0.0529) for the high TNF alpha group. Discussion: Coated-platelets and TNF alpha predict TIA/stroke in asymptomatic carotid stenosis at 21 months. These findings expand on our previous work in coated-platelets and asymptomatic carotid stenosis and suggest that coated-platelets may represent a common link between hemostatic and inflammatory mechanisms of plaque instability.

Mesoporous silica nanoparticles carried on chitosan microspheres for traumatic bleeding control.

Chitosan has been made into various hemostats, but their hemostatic efficiency for controlling severe traumatic bleeding is still inadequate. The aim of this work is to make quick hemostats by incorporating mesoporous silica nanoparticles into chitosan. Porous chitosan-silica composite microspheres (CSMS-S) with high hemostatic efficacy were fabricated through a combination of the microemulsion, thermally induced phase separation, and surfactant templating method. A large number of mesoporous silica nanoparticles were formed on and within the CSMS-S microspheres, which had abundant surface and inner macropores. The synergetic two hemostatic mechanisms from chitosan and mesoporous silica nanoparticles let CSMS-S composite microspheres with proper amount of silica displayed better hemostatic potential than the single component porous chitosan microspheres (CSMS). Within a same time interval, the whole blood clotting kinetics showed that CSMS-S could form larger blood clots than CSMS. The hemostatic time of CSMS-S was down to 97 s from 114 s of CSMS in the rat liver laceration model. The cytotoxicity and histological analysis proved that CSMS-S was a safe hemostatic agent without noticeable adverse effects on tissues around the wound. Our results demonstrate that CSMS-K is a promising quick hemostatic agent for traumatic hemorrhaging control.

Congenital hemophilia: a new treatment paradigm

Hemophilia is the most common congenital coagulation disorder, characterized by a tendency to bleed severely. Treatment is based on the replacement of defective FVIII or FIX. Following the introduction of recombinant FVIII and FIX, the treatment paradigm of the disease is shifting from episodic to prophylactic treatment with regular the infusion of factor concentrates. Since 2000, several new recombinant FVIII and FIX products with longer half-life have been developed by pegylation protein modification and other technologies, resulting in improved quality of life for patients with hemophilia. Recently, therapeutics with novel hemostatic mechanisms have been developed to overcome several unmet needs. FVIII (a), mimicking bispecific antibody recognizing FIX (a) /FX, has been approved in Japan. The product has several advantages, including a much longer half-life spanning 30 days, subcutaneous injectability, and effectiveness irrespective of the presence of FVIII inhibitor. The paradigm of hemophilia treatment is now shifting towards intact joint function and higher activity.