Changes In Coagulation Parameters Research Articles

Influences of ulinastatin on acute lung injury and time phase changes of coagulation parameters in rats with burn-blast combined injuries

Influences of ulinastatin on acute lung injury and time phase changes of coagulation parameters in rats with burn-blast combined injuries

Is Extracorporeal CO2 Removal Really "Safe" and "Less" Invasive? Observation of Blood Injury and Coagulation Impairment during ECCO2R.

Extracorporeal CO2 removal (ECCO2R) is promoted with attributes like "safe" and "less invasive" compared with (high-flow) venovenous extracorporeal membrane oxygenation (ECMO) systems. With our experience in coagulation disorders during ECMO therapy with this observational study, we for the first time prospectively evaluate hemolysis and coagulation disorders during ECCO2R. Eight consecutive patients with predominant hypercapnic respiratory failure were treated with the Hemolung respiratory assist system (Alung-Technologies, Pittsburg, PA). Bleeding as well as changes of coagulation parameters was prospectively assessed. Overall therapy was observed in seven patients with 52 treatment days. In four of seven patients (57%), relevant clinical bleeding symptoms occurred. Thrombocytopenia, hemolysis, factor XIII deficiency and acquired von Willebrand syndrome (loss of high-molecular-weight von Willebrand factor multimers) were typical findings, and the patients spontaneously recovered after discontinuation of the extracorporeal system. In one patient, extracorporeal system stopped because of thrombotic occlusion. Six of seven patients required transfusion of red blood cells. Our observation shows that even low-flow extracorporeal lung support is associated with relevant clinical bleeding symptoms, blood cell injury, development of acquired von Willebrand syndrome and need for transfusion. In our opinion, it therefore is too early to quote ECCO2R "safe" and "less invasive."

Assessing Coagulation by Rotational Thromboelastometry (ROTEM) in Rivaroxaban-Anticoagulated Blood Using Hemostatic Agents.

Patients (age >18 years; non-pregnant) on rivaroxaban, presenting to the emergency department (ED) at two large, university-based medical centers, were recruited. Subjects (n=8) had blood drawn and analyzed using ROTEM with and without the presence of a kaolin-based and a chitosan-based hemostatic agent. The percentage of patients whose ROTEM parameters responded to the hemostatic agent and percent changes in coagulation parameters were calculated. Data points analyzed included: CT, CFT, and MCF. Of the samples treated with a kaolin-based hemostatic agent, seven (87.5%) showed reductions in CT, eight (100.0%) showed reductions in CFT, and six (75.0%) showed increases in MCF. The average percent change in CT, CFT, and MCF for all patients was 32.5% (Standard Deviation [SD]: 286; Range:-75.3 to 740.7%); -66.0% (SD:14.4; Range: -91.4 to -44.1%); and 4.70% (SD: 6.10; Range: -4.8 to 15.1%), respectively. The corresponding median percent changes were -68.1%, -64.0%, and 5.2%. Of samples treated with a chitosan-based agent, six (75.0%) showed reductions in CT, three (37.5%) showed reductions in CFT, and five (62.5%) showed increases in MCF. The average percent changes for CT, CFT, and MCF for all patients were 165.0% (SD: 629; Range:-96.9 to 1718.5%); 139.0% (SD: 174; Range: -83.3 to 348.0%); and -8.38% (SD: 32.7; Range:-88.7 to 10.4%), respectively. The corresponding median percent changes were -53.7%, 141.8%, and 3.0%. Rotational thromboelastometry detects changes in coagulation parameters caused by hemostatics applied to rivaroxaban-anticoagulated blood. These changes trended in the direction towards improved coagulability, suggesting that kaolin-based and chitosan-based hemostatics may be effective at improving coagulation in these patients. Bar J , David A , Khader T , Mulcare M , Tedeschi C . Assessing coagulation by rotational thromboelastometry (ROTEM) in rivaroxaban-anticoagulated blood using hemostatic agents. Prehosp Disaster Med. 2017;32(5):580-587.

Safety and Efficacy of Enoxaparin Prophylaxis in Adults Receiving Peg-Asparaginase Containing Induction Regimens for Acute Lymphoblastic Leukemia (ALL)

Background:Peg-asparaginasecan cause dysregulationof pro-coagulant and anti-coagulant proteins, resulting in a significant risk of venous thromboembolism(VTE) in ALL, particularly in adults undergoing induction chemotherapy. In late 2014, we adopted a policy at our institution to use prophylactic dose ofenoxaparin 40 mg daily for up to 3 weeks following the administration of peg-asparaginase. Patients are also to undergo monitoring of complete blood count, and coagulation parameters including fibrinogen and anti-thrombin. Enoxaparin may be held if patients develop severe thrombocytopenia (platelet count <30,000/µL). Cryoprecipitate is given if fibrinogen drops below 100 mg/dl. In the present study, we aim to analyze primarily the safety, and secondarily the efficacy ofenoxaparin prophylaxis in this setting and highlight the changes in coagulation parameters following peg-asparaginase use during induction therapy.Methods:This is a single-center study of17 consecutive adult patients (>18 years old) treated for ALL with peg-asparaginasecontaining induction regimen before and after the establishment of institutional policy to useenoxaparinprophylaxis. Patients were identified from hospital research database. The diagnoses were verified. Medical records were reviewed for the occurrence of any clinically relevant bleeding and VTE within 3 months of receiving peg-asparaginase. Levels of coagulation parameters, whenever available, were collected at baseline and at weekly intervals for up to 4 weeks after receiving peg-asparaginase. The risk of bleeding and VTE among patients receivingenoxaparinwas compared to those who did not receiveenoxaparin. Fisher exact test was used for testing the association of categorical variable, and binomial exact test was used for computing confidence intervals. T-test or nonparametric test was used for comparing the continuous variables depending on whether or not the data were normally distributed.Results:The patient population consisted of 59% females. Mean age was 35 years. Histology consisted of Pre-B ALL in 76%, pre-T ALL in 18% and mixed lineage leukemia in 6%. 88% percent received pediatric-type chemoregimenand intramuscular peg-asparaginase; the most common doses of peg-asparaginaseincluded 2000 mg/m2 (41%) and 2500 mg/m2 (35%). Duration ofenoxaparin prophylaxis was 21 days in 66.7% and 7 days in 33.3%. Average changes in coagulation parameters at baseline and at weekly intervals following the use of peg-asparaginase therapy are highlighted in figures 1 and 2. The drop inantithrombin and fibrinogen levels was the highest during the first two weeks after the administration of peg-asparaginase. 41% of patients required cryoprecipitate (median 15 units, range 5-35 units over 4 weeks). No patients, including theenoxaparin group, had any clinically relevant bleeding event. The risk of VTE was 18% (95% confidence 4-43%); 2 out of 3 VTE events were cerebral venous thrombosis. No VTE occurred in theenoxaparin prophylaxis group (n=9), whereas 37% of patients (3 out of 8 patients), who did not receiveenoxaparin, developed VTE.Enoxaparin prophylaxis was associated with a trend towards a lower risk of VTE, however, the difference was not statistically significant (p=0.08).Conclusion:Within the limits of this study, in adult ALL patients receiving peg-asparaginase, the use of daily prophylactic dose ofenoxaparinmay not be associated with an increased risk of clinically relevant bleeding, and may have a potential to lower the risk of VTE. Patients receivingenoxaparin, however, should be carefully monitored for the need of platelet transfusion and cryoprecipitate supplementation. The difference in the risk of VTE was not statistically significant, which may be, in part, due to a small sample size.Antithrombindepletion may also contribute to a reduction in the efficacy ofenoxaparin. Larger prospective studies should be performed to validate the preliminary findings. [Display omitted] [Display omitted] DisclosuresArmitage:Spectrum Pharmaceuticals: Consultancy; Roche: Consultancy; Conatus - IDMC: Consultancy; GlaxoSmithKline IDMC: Consultancy; ZiopharmOncology: Consultancy; Tesaro bio Inc: Membership on an entity's Board of Directors or advisory committees. Lunning:Genentech: Consultancy; AbbVie: Consultancy; Bristol-Myer-Squibb: Consultancy; Juno: Consultancy; Spectrum: Consultancy; Pharmacyclics: Consultancy; Celgene: Consultancy; Gilead: Consultancy; TG Therapeutics: Consultancy.

Correlation of Coagulation Pathway Parameters with BNP, Ejection Fraction and NYHA Class in Heart Failure

&lt;p&gt;Abstract&lt;/p&gt;&lt;p&gt; &lt;/p&gt;&lt;p&gt;Background&lt;/p&gt;&lt;p&gt;The upregulation of inflammation and coagulation in addition to the sympathetic nervous system is known and reported in congestive heart failure. This study was undertaken to assess the correlations of the changes in coagulation parameters with functional class, ejection fraction and brain natriuretic peptide levels.&lt;/p&gt;&lt;p&gt; &lt;/p&gt;&lt;p&gt;Methods&lt;/p&gt;&lt;p&gt;A small prospective study was conducted in dilated cardiomyopathy (DCM) patients.&lt;/p&gt;&lt;p&gt;The protocol was approved by the Hospital IRB ( Scott and White Memorial, Temple, TX 76508). Statistical analysis was conducted using the online Vassar stats system . Spearman’s rank order correlation was derived for all the correlations mentioned in this paper.&lt;/p&gt;&lt;p&gt; &lt;/p&gt;&lt;p&gt;Results&lt;/p&gt;&lt;p&gt;PT, PTT, INR and d-dimer levels were significantly different in the two groups and correlated positively and significantly with BNP and New York Heart Association class . Statistically significant negative correlation was noted with ejection fraction. fibrinogen levels did not correlate significantly with BNP, New York Heart Association class or ejection fraction.&lt;/p&gt;&lt;p&gt; &lt;/p&gt;&lt;p&gt;Conclusions&lt;/p&gt;&lt;p&gt;Coagulation pathway parameters correlate significantly with BNP, functional class and ejection fraction in this study. The study is limited by its size and the fact that only dilated non- ischemic cardiomyopathy patients were included. Larger studies are required to further understand the complex interactions of biochemical pathways noted in heart failure.&lt;/p&gt;&lt;p&gt; &lt;/p&gt;

Complication rates of ultrasound-guided liver biopsies in dogs and cats

Purpose: The interpretation of ultrasound detectable liver changes is very difficult. The diagnosis can be made after examination of a liver specimen which could be taken by ultrasound guidance. There are some known complications associated with ultrasound-guided biopsies. The most common complication after sampling is bleeding which could lead to death. The aim of the study is to prove the correlation of observable ascites and changes in coagulation parameters.

A Snapshot of Coagulopathy After Cardiopulmonary Bypass.

Cardiac surgery involving cardiopulmonary bypass (CPB) is often associated with important blood loss, allogeneic blood product usage, morbidity, and mortality. Coagulopathy during CPB is complex, and the current lack of uniformity for triggers and hemostatic agents has led to a wide variability in bleeding treatment. The aim of this review is to provide a simplified picture of the data available on patients' coagulation status at the end of CPB in order to provide relevant information for the development of tailored transfusion algorithms. A nonsystematic literature review was carried out to identify changes in coagulation parameters during CPB. Both prothrombin time and activated partial thromboplastin time increased during CPB, by a median of 33.3% and 17.9%, respectively. However, there was marked variability across the published studies, indicating these tests may be unreliable for guiding hemostatic therapy. Some thrombin generation (TG) parameters were affected, as indicated by a median increase in TG lag time of 55.0%, a decrease in TG peak of 17.5%, and only a slight decrease in endogenous thrombin potential of 7%. The most affected parameters were fibrinogen levels and platelet count/function. Both plasma fibrinogen concentration and FIBTEM maximum clot firmness decreased during CPB (median change of 36.4% and 33.3%, respectively) as did platelet count (44.5%) and platelet component (34.2%). This review provides initial information regarding changes in coagulation parameters during CPB but highlights the variability in the reported results. Further studies are warranted to guide physicians on the parameters most appropriate to guide hemostatic therapy.

Elevated D-dimer and fibrinogen levels in serum of preoperative bone fracture patients.

The changes of coagulation parameters in preoperative fracture patients reflect the coagulation status before surgery. We did retrospective assessment of preoperative fracture patients (n = 113) admitted to the hospital between September 2013 and September 2014. The control group were selected from healthy adults (n = 113) with matched age and gender. Platelet, PT INR, APTT, fibrinogen (FIB) and D-dimer values were collected and analyzed. PT INR level was 1.043 ± 0.119, APTT was 31.91 ± 7.56 s, FIB was 320.6 ± 71.8 mg/dl and D-dimer was 1283 ± 1582 ng/ml for the fracture patients. For the control group, PT INR level was 0.9976 ± 0.0602, APTT was 33.22 ± 2.55 s, FIB was 277.3 ± 44.7 mg/dl and D-dimer was 97.53 ± 63.90 ng/ml. Meanwhile, D-dimer levels of different sites of fractures were also measured: Femora 2448 ± 1961 ng/ml; Humerus 792.4 ± 691.2 ng/ml; Ulna/Radius 619.4 ± 843.7 ng/ml; Vertebra 647.7 ± 787.1 ng/ml; Tibia/Fibula 496.3 ± 268.8 ng/ml; Clavicle 260.9 ± 170.9 ng/ml; Ankle 415.4 ± 286.6 ng/ml. To conclude, D-dimer and fibrinogen levels get higher in preoperative fracture patients than controls. Besides, D-dimer levels are significantly different among different locations of fractures, and our data revealed that D-dimer levels of Femora fracture were higher than other sites.

Effect of various pneumoperitoneum pressures on femoral vein hemodynamics during laparoscopic cholecystectomy.

High intra-abdominal pressure and reverse Trendelenburg position during laparoscopic cholecystectomy (LC) are risk factors for venous stasis in lower extremity. Lower limb venous stasis is one of the major pathophysiological elements involved in the development of peri-operative deep vein thrombosis. Low pressure pneumoperitoneum (7-10mmHg) has been recommended in patients with limited cardiac, pulmonary or renal reserve. The purpose of this study was to observe the effect of various pneumoperitoneum pressures on femoral vein (FV) hemodynamics during LC. A total of 50 patients undergoing elective LC were enrolled and they were prospectively randomized into two groups containing 25 patients each. In group A high pressure pneumoperitoneum (14mmHg) and in group B low pressure pneumoperitoneum (8mmHg) was maintained. Comparison of pre-operative and post-operative coagulation profile was done. Preoperative and intraoperative change in femoral vein diameter (FVD) (AP and LAT), cross-sectional area (CSA) and peak systolic flow (PSF) during varying pneumoperitoneum pressure was recorded in FV by ultrasound Doppler. First measurement (pre-operative) was carried out just after the induction of anesthesia before creation of pneumoperitoneum and second measurement (intra-operative) was taken just before completion of surgery with pneumoperitoneum maintained. Changes in coagulation parameters were less significant at low pressure pneumoperitoneum. There was statistical significant difference in the pre-operative and intra-operative values of FVD, CSA and PSF in both groups when analyzed independently (P=0.00). There was no significant difference in pre-operative values of FVD, CSA and PSF (P>0.05) among two groups but when the comparison was made between the intra-operative values, there was significant increase in FVD (AP) (P=0.016), CSA (P=0.00) and decrease in PSF (P=0.00) at high pressure pneumoperitoneum. This study provides evidence of using low pressure pneumoperitoneum during LC as changes in FV hemodynamics and coagulation parameters were less pronounced at low pressure pneumoperitoneum.

Effects of Different Time Protocols Treatment on Coagulation Parameters of Sheep Injected With Hemiscorpius lepturus Venom

Background: Hemiscorpius lepturus is one of the most dangerous scorpion species, endemic in Khuzestan province. Its venom has hemolytic activity and can lead to hemoglobinuria and death. Objectives: The aim of this study was to determine the effects of three different time treatment protocols on changes of coagulation parameters in sheep received Hemiscorpius lepturus venom. Materials and Methods: Sixteen healthy male lambs were divided randomly into four groups. Hemiscorpius lepturus venom (0.01 mg/kg of body weight) injected subcutaneously. Blood samples were taken at 30 minutes before and 1, 6, 12, 24, 48, 96 and 168 hours after injection. The sheep of group 1 were treated only by injection of Hemiscorpius lepturus venom. In groups 2, 3 and 4 (Experimental groups), treatment of animals began at 1, 24 and 48 hours respectively after the venom injection. In addition to intravenous injection of 5 mL antivenom, supportive therapy was performed as well. Prothrombin time (PT), activated partial thromboplastin time (APTT) and fibrinogen were measured by commercial kit and platelet (PLT) count was performed by hematology analyzer. All results were statistically analyzed using two way repeated measures analysis of variance. Results: In the studied groups, the effect of time on PT and platelets counts was significant (P < 0.05); however, it did not have a significant effect on the amounts of PTT and fibrinogen. No significant statistic difference was found regarding four factors measured between different treatment groups. Interaction of time and treatment groups had significant effect only on the platelet counts (P < 0.05). Conclusions: Hemiscorpius lepturus venom in sheep can cause severe changes in some of the coagulation factors. This should be considered as part of the pathogenesis of scorpion sting and seriously in the treatment protocol of scorpion sting victims.

Effect of Low and High Dose Sugammadex on the Coagulation and Fibrinolytic System in Rats

Background. Sugammadex is a new reversal agent that has entered use recently. It is known that with sugammadex some changes in coagulation parameters occur without documented clinical results. Aim of the Work. The objective of this study was to identify effects of sugammadex on liver functions, coagulation, and fibrinolytic systems. Methods. Thirty-six rats were randomized into six groups: Group I, control; Group II, rocuronium group; Group III, sugammadex administered in 16 mg kg−1 dose; Group IV, sugammadex administered in 96 mg kg−1 dose; Group V, rocuronium and sugammadex administered in 16 mg kg−1 dose; and Group VI, rocuronium and sugammadex administered in 96 mg kg−1 dose. After 120 minutes, blood samples were obtained for prothrombin time, activated partial thromboplastin time, D-dimer, fibrinogen, aspartate aminotransferase, alanine aminotransferase, albumin, platelet, and mean platelet volume analyses. Results. Compared to the control group, in all groups measured parameters did not show any effect from a statistical viewpoint either due to the administered drugs alone or due to interaction effects. Conclusion. The conclusion was reached that administration of sugammadex in rats did not have any significant effect on the fibrinolytic system, coagulation parameters, and liver function.

Low-dose recombinant factor VIIa for reversing coagulopathy in patients with isolated traumatic brain injury

PurposeThe purpose of this study was to investigate the role of low-dose recombinant factor VIIa (rFVIIa) (20 μg/kg) in reversing coagulopathy in patients with isolated traumatic brain injury (TBI). Materials and methodsPatients with isolated TBI and coagulopathy at admission were enrolled prospectively from January 2010 to December 2011. The patients were divided into 2 groups: the rFVIIa and the no-rFVIIa groups. In the rFVIIa group, patients received a single dose of 20 μg/kg rFVIIa intravenously to reverse their coagulopathy in addition to blood products. Patients in the no-rFVIIa group received only blood products to correct the coagulopathy. The clinical outcome variables evaluated included changes in coagulation parameters after administration for reversing coagulopathy, the occurrence of progressive hemorrhagic injury (PHI), intensive care unit length of stay, the incidence of thromboembolic complications, inhospital mortality, and 90-day Glasgow Outcome Scale. ResultsEighty-seven patients were ultimately included in this study. Of them, 49 patients were treated with blood products alone, whereas 38 patients also received rFVIIa to reverse their coagulopathy. The improvement in international normalized ratio was greater in the rFVIIa group (0.26 [0.18-0.39]) than in the no-rFVIIa group (0.06 [−0.11 to 0.30]) (P = .001). In addition, the improvement in lactate was also greater in the rFVIIa group (0.33 [−0.18 to 0.54]) than in the no-rFVIIa group (0.04 [−0.25 to 0.20]) (P = .029). During the period after we began to correct the coagulopathy, PHI occurred in 19 patients (38.8%) in the no-rFVIIa group, which was significantly higher than that in the rFVIIa group (7, 18.4%; P = .040). The rate of cerebral infarction was similar in both groups (10.2% vs 5.3%). There was a trend indicating that low-dose rFVIIa therapy was associated with a lower mortality, but the association was not statistically significant (P = .266). ConclusionsThe use of low-dose rFVIIa (20 μg/kg) is effective for correcting coagulopathy in patients with TBI without an increase in thromboembolic events. Moreover, it is more effective for preventing the occurrence of PHI.

Coagulation effects of mannitol in combination with 0.9% normal saline or hydroxyethyl starch in patients undergoing supratentorial craniotomy: A preliminary report

Abstract Background: Neurosurgical patients often require administration of both, mannitol and hydroxyethyl starch (HES). A recent in vitro study demonstrated that HES in combination with mannitol could disturb coagulation parameters and should be avoided in neurosurgical practice. The aim of our study was to evaluate coagulation abnormalities due to mannitol when administered alone and in combination with HES in patients undergoing craniotomy for various intracranial brain tumours. Materials and Methods: We enrolled 30 adult patients undergoing craniotomy. Patients were randomised into two groups using a computer generated randomisation chart. Interventions: Group A: Patients received 10 ml/kg 0.9% normal saline and 1 g/kg mannitol and Group B: Patients received 10 ml/kg, HES 130/0.4, and 1 gm/kg mannitol; immediately after induction of general anaesthesia. Rotational thromboelastography was done immediately after induction of general anaesthesia and 5 min after administration of mannitol. Measured parameters of blood coagulation were clotting time (CT) and clot formation time (CFT) with EXTEM and maximum clot firmness (MCF) with EXTEM and (FIBTEM). Results: Fourteen patients in each group completed the study. Insignificant change was noted in CT; CFT altered significantly from the baseline in both the groups (P &lt; 0.05). MCF with FIBTEM did not change significantly from baseline (P &gt; 0.05), but significantly differed between groups (P = 0.001). However, all values were in normal range. Conclusion: Mannitol 1 g/kg and HES 10 ml/kg can be safely administered in patients undergoing craniotomy for supratentorial tumours, without clinically significant changes in coagulation parameters.

Coagulation parameters do not change during luteal phase and pregnancy in cats

Changes in coagulation parameters depending on reproductive status and pregnancy have been previously reported in both human and other veterinary species. The objective of this study was to determine if different reproductive status affects coagulation parameters in queens. Blood samples from 66 queens submitted to spay surgery were obtained. A hemostatic panel including platelet count, prothrombin time, activated partial thromboplastin time, fibrinogen concentration, and D-dimer and also progesterone concentrations were measured before surgery. According to progesterone results and embryo vesicles diameter, four groups were established: (1) nonpregnant queens with low (≤1 ng/mL) progesterone concentration (LP) (n = 33); (2) nonpregnant queens with high (≥2 ng/mL) progesterone concentration (n = 8) (HP); (3) first half of pregnancy (n = 12); and (4) second half of pregnancy (n = 13). None of the evaluated parameters showed statistically significant differences among the different groups. There was no significant linear correlation between progesterone values and coagulation parameters. In conclusion, neither the presence of the embryo nor the higher values of progesterone concentration induced statistically significant changes in the coagulation profile studied.

Changes in the levels of endothelium-derived coagulation parameters in nonalcoholic fatty liver disease

In a majority of patients with nonalcoholic fatty liver disease (NAFLD), cardiovascular risk factors including diabetes mellitus type 2, abdominal obesity, and metabolic syndrome are present. The purpose of this study is to investigate the presence of endothelial injury and the changes in coagulation parameters in NAFLD patients. For this purpose, plasma levels of von Willebrand factor (vWF), thrombomodulin, urokinase plasminogen activator (uPA), plasminogen activator inhibitor-1 (PAI-1), and tissue factor pathway inhibitor (TFPI) in patients with NAFLD were measured. There was a significant difference in vWF and TFPI levels between patient and control groups (P < 0.05). However, no statistically significant difference was obtained in PAI-1, uPA, and thrombomodulin levels between the two groups (P > 0.05). According to our results, an increase in vWF and TFPI levels indicates an endothelial injury in NAFLD cases.

Placebo-Controlled, Double-Blind, First-In-Human, Ascending Single Dose and Multiple Dose, Healthy Subject Study Of Intravenous-Administered SelG1, a Humanized Anti-P-Selectin Antibody In Development For Sickle Cell Disease

SelG1 is a humanized anti-P-selectin monoclonal antibody being developed as a treatment for sickle cell disease (SCD). Extensive data have been published that suggest a pivotal role for P-selectin in the pathophysiology of SCD. Much of this work has been conducted in mice engineered to express human β hemoglobin S (sickle cell hemoglobin). These mice have a remarkably similar disease pathology to that observed in human SCD including vasoocclusion. Using these mice, investigators have demonstrated P-selectin interactions between the endothelium and sickled red blood cells, leukocytes and platelets. Additional studies have demonstrated direct P-selectin mediated binding of leukocytes with platelets. All of these cell-cell interactions have been implicated in SCD vasoocclusion. Further, blockade or genetic absence of P-selectin decreases or eliminates these cell-cell interactions and vasoocclusion.A Phase I clinical study was conducted to evaluate the safety, pharmacokinetics (PK), pharmacodynamics (PD), and immunogenicity of SelG1. This was a single-center, double-blind, placebo-controlled, first-in-human, ascending single dose and multiple dose study of intravenous (IV)-administered SelG1 in healthy adult male and female subjects.There were 5 dosing cohorts in the study (A through E):Ascending single dose cohorts:Cohort A:0.2 mg/kg IV dose of SelG1 (n=3) or placebo (n=1);Cohort B:0.5 mg/kg IV dose of SelG1 (n=3) or placebo (n=1);Cohort C:1.0 mg/kg IV dose of SelG1 (n=3) or placebo (n=1);Cohort D:5.0 mg/kg IV dose of SelG1 (n=6) or placebo (n=2).Multi-dose cohort:Cohort E:two 8.0 mg/kg IV doses of SelG1 (n=5) or placebo (n=2); the doses were given 2 weeks apart.In Cohorts A through D, SelG1 was slowly eliminated (mean t1/2 = 75.6 to 500 hours). Mean t1/2 values increased in a dose dependent manner. The exposure to SelG1 (mean Cmax, AUC0-t, and AUC0-∞) increased in a greater than proportional manner over the dose range. In Cohort E, SelG1 was slowly eliminated (mean t1/2 = 363 hours for the second infusion). The mean Cmax and AUC0-336values were 1.6- and 1.7-fold higher, respectively, after the second infusion relative to the first infusion. The PD data demonstrate that P-selectin function was completely blocked for a minimum of 28 days in Cohort D and at least 56 days in Cohort E.Twenty-six of the 27 subjects who received study drug completed the study, with 1 placebo subject in Cohort D withdrawing himself from the study due to the required travel commitment. There were no deaths, serious adverse events, or severe AEs reported in any subject. There were no increases in the number or severity of AEs with increasing dosages or with multi-dose administration. The percentage of subjects experiencing an AE was similar between the SelG1-treated subjects and the placebo-treated subjects; in Cohorts A-D, 66.7% of SelG1-treated subjects and 60.0% of placebo subjects reported at least 1 AE, while in Cohort E, 60.0% of SelG1-treated subjects and 50.0% of placebo-treated subjects reported at least 1 AE. Only 1 AE occurred in more than 1 subject; vessel puncture site hematoma occurred in 1 subject of Cohort A, 1 subject of Cohort C, and 2 subjects of Cohort E. All other AEs occurred in only 1 subject and were mild to moderate in severity. No AEs in any subject were deemed “related” to study drug.No clinically significant findings were noted from vital sign measurements, physical examinations, or 12-lead ECGs for this study. No biochemistry, hematology, or other laboratory data were reported as clinically significant or were reported as AEs; there were no trends that indicated increases or decreases in mean or median values over time, and there were no dose-dependent increases or decreases in mean or median values. There were no demonstrable changes in coagulation parameters or increased bleeding tendencies. No specific antibody response to SelG1 occurred in any of the subjects.In summary, the administration of SelG1 was well tolerated in this group of healthy male and female subjects. A Phase II clinical study to evaluate the clinical efficacy of SelG1 in SCD patients is currently underway. Disclosures:Stocker:Selexys Pharmaceuticals: Employment, Equity Ownership. Mandarino:Selexys Pharmaceuticals: CRO Other. Kawar:Selexys Pharmaceuticals: Employment, Equity Ownership, Patents & Royalties. Alvarez:Selexys Pharmaceuticals: Employment, Equity Ownership, Patents & Royalties. Falconer:Selexys Pharmaceuticals: Employment, Equity Ownership. Rollins:Selexys Pharmaceuticals: Employment, Equity Ownership, Membership on an entity's Board of Directors or advisory committees. Rother:Selexys Pharmaceuticals: Employment, Equity Ownership.

The First In Vitro and In Vivo Assessment Of Anfibatide, a Novel Glycoprotein Ib Antagonist, In Mice and In a Phase I Human Clinical Trial

BackgroundPlatelet adhesion and subsequent aggregation at the site of vascular injury are critical for hemostasis and thrombosis. It has been well accepted that interaction between the GPIb complex and von Willebrand factor (VWF) plays a key role in initiation of platelet adhesion, particularly at high shear. Platelet surface integrin αIIbβ3, through interaction with fibrinogen or other ligands, then mediates platelet aggregation to form a stable hemostatic plug or thrombus. Recently, the indispensable role of the GPIb-VWF interaction in platelet aggregation at extremely high shear (e.g. > 10,000s-1; areas of stenosis following arteriosclerosis and/or thrombus growth) has been highlighted. Therefore, both the GPIb complex and αIIbβ3 are considered major targets for antithrombotic therapies. Interestingly, although several inhibitors of αIIbβ3 have been developed for antithrombotic therapies, no drug has been developed to target the GPIb complex even though there are limitations for anti-αIIbβ3 therapies. The GPIb complex is, therefore, an attractive target for anti-thrombotic therapy. Here, we evaluated the efficacy and safety in vitro and in vivo of Anfibatide, a novel GPIb antagonist, in mice and in a phase I clinical trial. MethodsAnfibatide was purified from venom of the Agkistrodon acutus snake and its purity was analyzed by mass spectrometry. The effect of Anfibatide on murine platelet function was assessed by in vitro platelet aggregometry, ex vivo perfusion chamber, and two complementary in vivo intravital microscopy models. The effects of Anfibatide on human platelet aggregation and thrombus formation were studied in vitro, and thrombealastography (TEG) was also performed. Most importantly, we evaluated the safety and efficacy of Anfibatide on platelet function and coagulation in a total of 94 healthy human volunteers in a phase I clinical trial. ResultsMALDI-TOF mass spectrometry of Anfibatide showed only one peak and the mass to charge ratio is 29799.7. Anfibatide specifically inhibited ristocetin-induced human platelet aggregation. Interestingly, Anfibatide was not able to inhibit botrocetin-induced murine platelet aggregation in plate-rich plasma (PRP), suggesting that its binding site may differ from other snake venom-derived GPIb antagonists. We found Anfibatide did not affect ADP-, TRAP- or collagen-induced aggregation in PRP, suggesting its specificity to GPIb. In ex vivo perfusion, Anfibatide strongly inhibited murine and human platelet adhesion, aggregation, and thrombus formation on a collagen-coated surface at both high and low shear flow conditions although it is far more sensitive at high shear. Importantly, Anfibatide effectively dissolved the preformed thrombi when we continuously perfused Anfibatide-treated whole blood through perfusion chambers, demonstrating its potential as an anti-thrombotic therapy. In the mesenteric arteriole thrombosis model, Anfibatide strongly inhibited platelet adhesion, thrombus formation, and prevented vessel occlusion in response to FeCl3 injury (P<0.05). At sites of laser-injured cremaster arterioles, Anfibatide also dramatically inhibited platelet accumulation and thrombus growth. Anfibatide did not cause significant murine platelet activation in vitro and had no significant change in coagulation parameters in TEG when we treated human whole blood with Anfibatide, suggesting it had minimal side effects. In the phase I clinical trial, results showed that Anfibatide can occupy approximately 95% of GPIb and inhibit up to 90% of ristocetin specific platelet aggregation. The inhibitory effect was undetectable four hours after Anfibatide was withdrawn. There were no serious adverse events, or deaths that occurred during the study. Anfibatide did not significantly prolong bleeding time, activated partial thromboplastin time (APTT), prothrombin time (PT), or thrombin time (TT). There was also no spontaneous bleeding or bleeding from blood collection sites. Anfibatide did not significantly affect platelet count and no anti-Anfibatide antibodies were detected in the subjects, suggesting that Anfibatide is well-tolerated in healthy individuals. ConclusionThese comprehensive studies in mice and human subjects and in the first clinical trial clearly demonstrated that Anfibatide is a safe and potent anti-platelet reagent with great potential for future anti-thrombotic therapy. Disclosures:Hou:Lee's pharmaceutical holdings limited: Research Funding. Lei:Lee's pharmaceutical holdings limited: Research Funding. Zhao:Lee's pharmaceutical holdings limited: Research Funding. Shen:Lee's pharmaceutical holdings limited: Research Funding. Zhou:Lee's pharmaceutical holdings limited: Research Funding. Wang:Lee's pharmaceutical holdings limited: Research Funding. Marshall:Lee's pharmaceutical holdings limited: Research Funding. Ni:Lee's pharmaceutical holdings limited: Research Funding.

Evaluation of Hemostaitc Parameters of Sudanese patients with liver Disease attending Khartoum Teaching Hospital

Background: Various hemostatic abnormalities can occur in patients with liver disease, the severity of these abnormalities is dependent on the degree of hepatic dysfunction. Liver disease can cause both quantitative and qualitative abnormalities in coagulation factors, fibrinolytic system and platelets abnormalities, with consequent variable impairment of coagulation parameters. Methods: In this case control study we examined the 60 liver diseases patients and 30 control healthy subjects, in Khartoum Teaching Hospital (Khartoum, Sudan) during the period 10/3/2012 to 12/6/2012. Prothrombin time (PT), Activated partial Thrmboplastine time (APTT) and fibrinogen level (FL) were determined and categorized by types of liver disease, age, and sex in all study subjects. Results: The result revealed that there were significant increased in (PT) (P=0.00), APTT (P=0.00) and significant decreased in fibrinogen level (P=0.00) among patients of liver disease when compared with control group. There were no significant changes in coagulation parameters related to age and gender. Conclusion: There were significant increased in PT and APTT associated with liver diseases and significant decreased in fibrinogen level among patients of liver disease when compared to normal control.

Abstract 112: Reconstitution with Saline Is More Appropriate than Arithmetic Correction When Examining Stress-Hemoconcentration Effects on Coagulation

Introduction: The goal of this study was to examine a new physiologically relevant method of correcting for hemoconcentration effects on stress-induced changes in coagulation parameters (i.e., activated partial thromboplastin time (APTT), prothrombin time (PT%), FVIII:C, and FVII:C). Hypotheses: We hypothesized that 1) Area-under-the-curve (AUC) for uncorrected PT% and FVII:C would be greater than AUC corrected arithmetically or with saline or plasma, 2) AUC for APTT uncorrected or corrected with baseline plasma would be less than AUC when corrected with saline and greater than AUC corrected arithmetically, and 3) AUC for FVIII:C would not differ between correction methods. Methods: Blood was drawn from 40 men during a 20-min baseline, a 6-min math stressor and a 20-min recovery period. Two reconstitution techniques were used to adjust for hemoconcentration during stress and recovery using the person’s own plasma from baseline or physiological saline equal to the amount of plasma lost during each period. Results: For PT%, uncorrected AUC (M = 30.6 ± 18.4) was significantly greater than AUC corrected with saline (M = -33.3 ± 25.5, p = .002) or arithmetically (M = -9.1 ± 20.3, p = .001) but was not significantly different from AUC corrected with plasma (M = 25.5 ± 20.8, p = .72). For FVII:C, uncorrected AUC (M = 21.0 ± 33.1) was significantly greater than AUC corrected arithmetically (M = -31.7 ± 36.1, p = .001), but was not significantly different from AUC corrected with saline (M = -6.4 ± 38.3, p = .17) or plasma (M = 33.8 ± 36.8, p = .47). For APPT, uncorrected AUC (M = -15.2 ± 4.9) was significantly less than AUC corrected with saline (M = -6.3 ± 5.2, p = .001) and greater than AUC corrected arithmetically (M = -26.7 ± 6.8, p = .007), but was not significantly different from AUC corrected with plasma (M = -13.5 ± 5.2, p = .47). For FVIII:C, the omnibus test was non-significant (p = .39), suggesting no differences between groups. Conclusions: Saline reconstitution appears to be a more biologically relevant correction method when examining hemoconcentration effects on clotting time and clotting activity, whereas the plasma reconstitution method and arithmetic correction do not seem appropriate. With the exception of FVIII:C, hemoconcentration appears to account for the changes in the coagulation parameters.

Short-term supplementation with Aronia melanocarpa extract improves platelet aggregation, clotting, and fibrinolysis in patients with metabolic syndrome

PurposeA diet rich in berries is believed to play a distinct role in the prevention of metabolic diseases associated with obesity. So far, there have been no published clinical observations evaluating the influence of Aronia melanocarpa on hemostasis. The aim of our study was to investigate the effects of A. melanocarpa extract (AM) supplementation on platelet aggregation, clot formation, and lysis in patients with metabolic syndrome (MS).MethodsMiddle-aged non-medicated subjects with MS (n = 38) and 14 healthy volunteers were included in this study. Patients with MS were treated with 100 mg of AM three times daily for 2 months.ResultsWe observed a significant reduction in the concentration of TC, LDL-C, and TG after AM supplementation. Beneficial changes in coagulation parameters were also observed. After 1 month of AM administration, we noticed significant inhibition of platelet aggregation. However, this effect became less pronounced after 2 months of supplementation. In the case of coagulation induced by endogenic thrombin, a significant decrease in the overall potential for coagulation was induced after 1 or 2 months of supplementation. Moreover, after 1 month of AM extract supplementation, we observed a beneficial reduction in the overall potential for clot formation and fibrinolysis.ConclusionsWe observed the normalization of hemostasis parameters in MS patients after both 1 and 2 months of AM administration. After 1 month of AM supplementation, we found favorable changes in regards to the overall potential for plasma clotting, clot formation, and lysis, as well as in the lipid profiles of subjects.