Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “HEMOSTATICS”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 991 records · Page 55Linked to original sources

Hemostatic imbalances produced by plasma exchange.

Ten patients who underwent intensive therapeutic plasma exchange were studied prospectively to determine the nature and extent of changes induced in their coagulation mechanisms. The patients' plasma was replaced with serum albumin and normal saline. Significant changes were noted acutely in the prothrombin time, activated partial thromboplastin time, plasma fibrinogen, and platelet counts. Chronically, significant decreases were found in plasma fibrinogen concentrations and platelet counts. Intensive plasma exchange with fluids devoid of coagulation factors results in defects in the normal hemostatic mechanism.

Adult↗

Increased local procoagulant action: a mechanism contributing to the favorable hemostatic effect of recombinant FVIIa in PLT disorders.

BACKGROUND: Recombinant FVIIa (rFVIIa) has been shown to improve hemostasis in patients with thrombocytopenia and to prevent or control bleeding episodes in patients with inherited deficiencies of major PLT glycoproteins, but the mechanism of action is not well understood. STUDY DESIGN AND METHODS: Effects of rFVIIa on hemostasis were explored with an in vitro perfusion technique. Blood samples, from healthy donors or from patients with congenital defects of PLT glycoprotein IIb-IIIa (GPIIb-IIIa), were anticoagulated with low-molecular-weight heparin. Experimental thrombocytopenia (<6000 PLTs/microL) was induced by a filtration procedure. rFVIIa was added to blood samples at therapeutic concentrations. A severe GPIIb-IIIa impairment was also induced by exposure of normal blood samples to a specific antibody. Perfusion studies were performed through annular chambers containing damaged vascular segments. The presence of fibrin and PLTs on the perfused subendothelium was morphometrically quantified. RESULTS: Under conditions of experimental thrombocytopenia, addition of rFVIIa enhanced fibrin formation in a dose-dependent manner (p < 0.05). Improvements in local fibrin generation and partial restoration of PLT interactions were also observed after incubation of blood from patients with Glanzmann's thrombasthenia with rFVIIa at 5 microg per mL (180 microg/kg). Similar improvements were observed in blood samples incubated with antibodies to GPIIb-IIIa. rFVIIa in whole normal blood also enhanced fibrin formation but PLT deposition was unaffected. Evaluation of prothrombin fragments 1 and 2 in the perfusates confirmed that rFVIIa increased thrombin generation in all cases. CONCLUSION: Our data indicate that rFVIIa promotes a procoagulant activity at sites of vascular damage. This mechanism could explain the beneficial hemostatic effect of rFVIIa in patients with thrombocytopenia or with Glanzmann's thrombasthenia.

Blood Coagulation↗

Effects of fixed low-dose warfarin on hemostatic factors in continuous ambulatory peritoneal dialysis patients.

Increased coagulation factors found in dialysis patients may explain in part the high prevalence of thrombotic cardiovascular disease. Several studies showed low-dose warfarin is effective in decreasing coagulation factors and preventing thrombosis without increasing the risk of bleeding. To evaluate the effects of fixed low-dose warfarin therapy on thrombogenesis in continuous ambulatory peritoneal dialysis (CAPD) patients, 76 CAPD patients were assigned randomly to treatment and disease control groups. The treatment group received 2 mg of warfarin daily for 12 months. International normalized ratio (INR) of the prothrombin time and plasma levels of factor VII, D-dimer, von Willebrand factor (vWF), and plasminogen activator inhibitor-1 (PAI-1) were measured before and 3, 6, and 12 months after the start of medication. The same parameters were measured in 30 healthy volunteers at the beginning of the study and in the disease control group during the study period. Of 76 patients, 60 completed the study. Deaths from atherosclerotic cardiovascular disease (cerebral infarction or acute myocardial infarction) occurred in 1 patient in the treatment group (n = 29) and 3 in the disease control group (n = 31), which was not statistically significant. No major bleeding occurred during the study period. With administration of warfarin, there was a small increase in INR in the treatment group. CAPD patients at baseline had significantly higher plasma factor VII, D-dimer, vWF, and PAI-1 levels than normal controls. Warfarin therapy lowered plasma factor VII and D-dimer levels. No change was seen in vWF and PAI-1 levels. In the disease control group, these hemostatic factors showed no change during the study period. There was a negative correlation between serum albumin and INR in the treatment group during the study period. Fixed low-dose warfarin was effective in partially reversing the thrombogenic coagulation profile in CAPD patients without a big increase in the risk of bleeding.

Anticoagulants↗

Management of heparin resistance during cardiopulmonary bypass: the effect of five different anticoagulation strategies on hemostatic activation.

OBJECTIVE: Attenuation of hemostatic activation is a central goal during CPB. However, this poses a problem in patients insensitive to heparin. The present investigation was performed to assess different strategies of managing patients with heparin resistance during CPB. DESIGN: A randomized, prospective clinical investigation. SETTING: A major European heart center. PARTICIPANTS: Five groups with 20 patients each were investigated. INTERVENTIONS: The groups were handled as follows: (1). maintenance of a target ACT, (2). maintenance of the target unfractionated heparin (UFH) level and supplementation of a UFH level-based strategy with (3). AT III, (4). the direct thrombin inhibitor r-hirudin, or (5). the short-acting platelet glycoprotein (GP) IIb/IIIa antagonist tirofiban. Platelet count and generation of contact factor XIIa, thrombin, and soluble fibrin were assessed. Samples were obtained before CPB and after CPB before protamine infusion. MEASUREMENTS AND MAIN RESULTS: There were no differences observed in the generation of factor XIIa. The UFH-based strategy and supplementation with AT III, r-hirudin, and tirofiban resulted in significantly reduced (p < 0.05) thrombin generation compared with ACT management. A significant reduction of fibrin formation was seen only in patients who received AT III, r-hirudin, or tirofiban supplementation to the UFH. The administration of tirofiban resulted in a significant preservation of the platelet count compared with the other groups. There were no significant differences in the postoperative blood loss. CONCLUSIONS: Activation of hemostasis during CPB in heparin-resistant patients most likely has to be attributed to stimulation of the tissue factor pathway. Even the sole use of high concentrations of UFH does not effectively inhibit this activation. Therefore, in these patients anticoagulation during CPB with UFH should be supplemented with either AT III, a short-acting direct thrombin inhibitor, or a short-acting platelet glycoprotein IIb/IIIa antagonist.

Aged↗

The effects of treatment with alpha-lipoic acid or evening primrose oil on vascular hemostatic and lipid risk factors, blood flow, and peripheral nerve conduction in the streptozotocin-diabetic rat.

Oxidative stress and defective fatty acid metabolism in diabetes may lead to impaired nerve perfusion and contribute to the development of peripheral neuropathy. We studied the effects of 2-week treatments with evening primrose oil (EPO; n = 16) or the antioxidant alpha-lipoic acid (ALA; n = 16) on endoneurial blood flow, nerve conduction parameters, lipids, coagulation, and endothelial factors, in rats with streptozotocin-induced diabetes. Compared with their nondiabetic littermates, untreated diabetic rats had impaired sciatic motor and saphenous sensory nerve-conduction velocity (NCV; P <.001), reduced endoneurial blood flow (P <.001), and increased serum triglycerides (P <.01), cholesterol (P < 0.01), plasma factor VII (P <.0001), and von Willebrand factor (vWF; P <.0001). Plasma fibrinogen and serum high-density lipoprotein concentrations were not significantly different. Treatment with either ALA or EPO effectively corrected the deficits in NCV and endoneurial blood flow. ALA was associated with marked and statistically significant decreases in fibrinogen, factor VII, vWF, and triglycerides (P <.01, paired t tests before v after treatment). In contrast, EPO was associated with significant (P <.05) increases in fibrinogen, factor VII, vWF, triglycerides, and cholesterol and a significant decrease in high-density lipoprotein. Changes in levels of coagulation factors and lipids, qualitatively similar to those found with EPO, were obtained with a diet containing sunflower oil (to control for calorific and lipid content) or with a normal diet alone. Blood glucose and hematocrit levels were not significantly altered by treatments. These data suggest that although both ALA and EPO improve blood flow and nerve function, their actions on vascular factors differ. The marked effects of ALA in lowering lipid and hemostatic risk factors for cardiovascular disease indicate potential antithrombotic and antiatherosclerotic actions that could be of benefit in human diabetes and merit further study.

Animals↗

Effects on hemostatic variables of desogestrel- and gestodene-containing oral contraceptives in comparison with levonorgestrel-containing oral contraceptives: a review.

In some studies third-generation oral contraceptives have been reported to be associated with a higher risk of venous thromboembolism than are second-generation oral contraceptives, whereas recent, more refined studies have not confirmed this. The reasons for the alleged differences are under discussion, and differential effects on hemostasis have been proposed. Eighteen studies comparing second- and third-generation oral contraceptives with respect to their effects on hemostasis were analyzed. Significant changes from baseline were reported for many variables with both second- and third-generation oral contraceptives without significant between-group differences. Also, in a combined analysis of nonsignificant changes, no consistent pattern of change emerged for any marker, with the exception of higher factor VII levels associated with third-generation oral contraceptives. However, factor VII is not related to venous thromboembolism risk. In addition, 1 cross-sectional study with an unvalidated assay reported a higher ratio of activated protein C sensitivity with third-generation oral contraceptives. Only 2 components of the hemostatic system (factor VII and activated protein C sensitivity ratio) emerged as potentially differentially affected by second- and third-generation oral contraceptives; the association with venous thromboembolism risk is questionable in the former case and unknown in the latter.

Contraceptives, Oral, Hormonal↗

Diagnosis of disseminated intravascular coagulation by hemostatic molecular markers.

In the present study, the positive rate of thrombin-antithrombin complex (TAT), plasmin-plasmin inhibitor complex (PPIC), soluble fibrin monomer (sFM), and D-dimer for the diagnosis of disseminated intravascular coagulation (DIC) was evaluated. The study comprised 307 patients with DIC, 123 with pre-DIC, and 121 with non-DIC. Plasma levels of TAT, PPIC, sFM, and D-dimer were significantly higher in DIC and pre-DIC patients than in non-DIC patients. In DIC patients, the positive rate of sFM was high and that of D-dimer was low; the positive rate of PPIC was higher in patients with hematopoietic malignancy than in those without this disease. In pre-DIC patients, the positive rate of all markers was low (<0.16), and the positive rate of PPIC was relatively high. In non-DIC patients, the positive rate of all hemostatic markers was low (<0.16), that of sFM being the lowest. Scoring the positive rate of TAT, PPIC, and sFM disclosed the following results: 72% of DIC patients had three or more points, 17.6% of pre-DIC patients had three or more points, and almost all (96.6%) non-DIC patients had two or less points. Scoring the positive rate of TAT, PPIC, and D-dimer disclosed the following results: 52.9% of DIC patients and 27.4% of pre-DIC patients had three or more points and almost all (96.7%) non-DIC patients had 2 or less points. These data suggest that the combination of TAT, PPIC, and sFM is useful for making the diagnosis of DIC.

Antifibrinolytic Agents↗

Changes of hemostatic variables during oral contraceptive use.

The use of oral contraceptives (OCs) has been known for many years to affect significantly almost all hemostatic parameters, but the challenge to relate these changes in a meaningful way to OC-induced increased venous thrombotic risk has not been met. New insights indicate that at least part of the answer can be found in the net effect of OC use on the efficacy with which the protein C pathway down-regulates thrombin formation. During OC use the (blood) plasma of a woman becomes resistant to the anticoagulant action of activated protein C (APC). The extent of this so-called acquired APC resistance as determined in a thrombin generation-based assay correlates remarkably well with the risk increases observed in clinical studies. Recent evidence indicates that the prothrombotic effect of the estrogen component ethinylestradiol in combined OC is counteracted by the progestagen component present in these preparations and that third-generation progestagens such as desogestrel or gestodene are less efficient with respect to this than the second-generation progestagen levonorgestrel.

Activated Protein C Resistance↗

Hemostatic system activation in patients with lupus anticoagulant and essential thrombocythemia.

Hemostatic system activation was estimated in the plasmas of 39 patients with LAC and 19 patients with ET by measuring concentrations of TAT complex and prothrombin F1+2. The concentrations of FVII, recognized previously as a risk factor for arterial thrombosis, were also measured. None of the patients had active thrombosis during this study. The mean TAT and F1+2 levels in LAC and ET plasmas were higher than the respective values in the plasmas of healthy control subjects. Compared with their respective controls, TAT levels were significantly higher in the LAC group (P < 0.05) and F1+2 was significantly higher in the ET group (P < 0.005). The mean FVIIt and FVIIz was significantly higher (P < 0.05 and P < 0.01, respectively) in LAC than control plasmas. Furthermore, the differences between FVIIt and FVIIz were significantly greater in LAC than control plasmas, indicating increased in vivo proteolysis of FVII in LAC. Although the mean concentrations of these two FVII parameters in ET plasma were not significantly different from those of normal plasmas, the FVII levels were higher in 30% of ET plasmas than the upper limit of controls. Our results are consistent with hypercoagulation in LAC and ET patients, and this may be a contributory factor for the increased rates of thrombosis associated with the two conditions.

Adolescent↗

[Hemostatic changes in idiopathic venous thrombosis in childhood and adolescence].

The prevalence of inherited thrombotic syndrome in the general population appears to be higher than that of inherited bleeding disorders. The most important candidates for screening are patients with unexplained venous thromboembolism at ages of less than 40 years: In 18 children and adolescents suffering from "idiopathic" vein thrombosis laboratory screening has been performed: PT, PTT, TT, platelet count, spontaneous platelet aggregation, von Willebrand factor, fibrinogen, plasminogen, antithrombin III, protein C, C1-inactivator, alpha-1-antitrypsin, alpha-1-antichymotrypsin, alpha-2-antiplasmin and alpha-2-macroglobulin. Compared to an age matched healthy control group in children with idiopathic vein thrombosis we could demonstrate in vitro platelet activation with significant enhanced platelet aggregation and elevated levels of von Willebrand factor in the onset of the disease. Antithrombin III, protein C, alpha-2-antiplasmin and alpha-2-macroglobulin were significantly decreased. These changes turned to be normal in the following 6 to 9 months. PT, PTT, TT, platelet count, plasminogen, alpha-1-antitrypsin, alpha-1-antichymotrypsin and c1-inactivator showed no alterations compared to the control. Platelet activation and alteration of platelet function in vivo and in vitro is established to initiate thrombosis. The von Willebrand's VIII molecule is involved in this step. The decreased inhibitors of the hemostatic system antithrombin III and protein C in the onset period of thrombotic diseases are discussed to be an increased turnover, whereas the decreased levels of alpha-2-antiplasmin and alpha-2-macroglobulin might be a counter-regulation to the thrombotic event, showing an "activated" fibrinolytic system.

Adolescent↗

Platelet hemostatic capacity (PHC) and fibrinolytic inhibitors during pregnancy.

Platelet hemostatic capacity (PHC) was measured in blood from pregnant patients during all three trimesters using the PFA-100 system. Closure times were shorter with both cartridge systems during pregnancy, compared to non-pregnant controls, suggesting increased PHC. Thrombin/antithrombin (TAT) complex and prothrombin fragment 1 + 2 (F 1+2) levels were elevated during pregnancy and increased over time. Also, plasma levels of plasminogen activator inhibitor 1 and 2 (PAI-1, PAI-2) increased during pregnancy. The data suggest increased coagulability during pregnancy. It is suggested that estrogen may play a role in this state of hypercoagulability. Seven days after delivery all of the measured parameters, except TAT levels, were again within normal range.

Adult↗

[The hemostatic and fibrinolytic system in normal subjects and myocardial infarct patients. Effect of a standardized aerobic and anaerobic ergometric stress test].

After clinical examination, 14 asymptomatic post-infarction male patients and 12 healthy control persons, aged 35-62 years, underwent two bicycle-ergometry tests. After a 20-min aerobic test of moderate intensity both groups had slight activation of the clotting system simultaneously with favorably increased fibrinolytic activity. After stepwise submaximal aerobic exercise, postinfarction patients had marked activation of the thrombocytic system; beta-thromboglobulin rose significantly from 36 to 102 ng/ml. But compared to the results in healthy persons, fibrinolytic activity was significantly reduced in the postinfarction patients (euglobulin lysis time 135 and 100 min, respectively). In three patients with unfavorable reactions of the hemostasis and fibrinolysis systems, ischemic changes or multifocal ventricular extrasystoles were recorded in the ECG after the second exercise test. These results indicate that intensive physical exercise in postinfarction patients can change the dynamic equilibrium between hemostasis and fibrinolysis in the direction of an increased clotting tendency. For this reason postinfarction patients and elderly untrained persons, especially those with an increased coronary risk factor, should avoid endurance training involving anaerobic exercise. On the other hand, moderate training at aerobic level favorably influences the hemostatic equilibrium in both healthy and postinfarction patients.

Adult↗

Hemostatic effect of tranexamic acid mouthwash in anticoagulant-treated patients undergoing oral surgery.

We carried out a placebo-controlled, double-blind, randomized study of the hemostatic effect of tranexamic acid mouthwash after oral surgery in 39 patients receiving anticoagulant agents because of the presence of cardiac valvular stenosis, a prosthetic cardiac valve, or a vascular prosthesis. Surgery was performed with no change in the level of anticoagulant therapy, and treatment with the anticoagulant agent was continued after surgery. Before it was sutured, the operative field was irrigated in 19 patients with 10 ml of a 4.8 percent aqueous solution of tranexamic acid (an inhibitor of fibrinolysis) and in 20 patients with a placebo solution. For seven days thereafter, patients were instructed to rinse their mouths with 10 ml of the assigned solution for two minutes four times a day. There were no significant differences between the two treatment groups in base-line variables, including the level of anticoagulation at the time of surgery. Eight patients in the placebo group had a total of 10 postoperative bleeding episodes, whereas only 1 patient in the tranexamic acid group had a bleeding episode (P = 0.01). There were no systemic side effects. We conclude that local antifibrinolytic therapy is effective in preventing bleeding after oral surgery in patients who are being treated with anticoagulants.

Adult↗

Bleeding Dieulafoy's lesions and the choice of endoscopic method: comparing the hemostatic efficacy of mechanical and injection methods.

BACKGROUND: Dieulafoy's lesion has unique endoscopic and histopathologic characteristics. This is a clinical trial of endoscopic therapy in 24 patients with Dieulafoy's lesions. METHODS: Patients were divided into 2 groups according to initial endoscopic treatment method. Data were analyzed with respect to clinical and endoscopic characteristics as well as outcomes. The 24 patients were evenly divided into mechanical (9 hemoclipping, 3 band ligation) and injection groups (12). RESULTS: The average number of therapeutic endoscopic sessions needed to achieve permanent hemostasis for the mechanical and injection groups were 1.17 and 1.67, respectively. Initial hemostasis was achieved in 91.7% of patients undergoing mechanical therapy and 75% of those undergoing injection therapy, with none in the former group needing subsequent surgery in comparison to 17% of the latter group. The rate of recurrent bleeding in the mechanical therapy group was significantly lower in comparison to the injection therapy group (8.3% versus 33.3%, p < 0. 05). CONCLUSIONS: Higher efficacy in terms of initial hemostasis and less recurrent bleeding was achieved by mechanical hemostatic therapy with hemoclip and band ligation compared with injection therapy. Endoscopic mechanical therapy is recommended as effective for bleeding Dieulafoy's lesions.

Adult↗

Hemostatic alterations in patients with acute, unilateral vestibular paresis.

OBJECTIVES: The etiopathogenesis of acute unilateral peripheral vestibulopathy (APV) still remains a matter of debate; ischemic changes in the circulation of the labyrinth may play a role. We consequently looked for possible hemostasis alterations in a group of patients with APV of an unknown nature. METHODS: We evaluated blood parameters known to be involved in circulation disorders, including total and HDL cholesterol, triglycerides, apolipoprotein A and B, lipoprotein(a), homocysteine, folate, prothrombin time, activated partial thromboplastin time, fibrinogen, D-dimer, antithrombin III, protein C, protein S, activated protein C resistance, and anticardiolipin IgG and IgM antibodies. A series of 23 patients affected with APV were consecutively referred to our department, in the acute phase, before treatment, and in the follow-up phase after 4 to 6 weeks of pharmacologic washout. The aforementioned blood parameters were also measured in a series of 15 patients with Menière's disease. RESULTS: The patients with APV in the acute phase compared with the patients with Menière's disease in the acute phase exhibited increased plasma levels of fibrinogen (mean, 338.3 +/- 135.9 SD vs 271.3 +/- 69.8 SD mg/dL, P = 0.05), increased plasma levels of D-dimer (mean, 320 +/- 207.8 SD vs 226.7 +/- 138.7 SD NG/mL), enhanced plasma levels of lipoprotein(a) (41.4 +/- 38.6 SD vs 16 +/- 18.2 SD mg/dL, F = 5.67, P = 0.02), high leukocyte count (9.1 +/- 2.7 SD vs 6.5 +/- 1.3 SD x 10(3)/microL; F = 8.42, P < 0.006), and low serum folate concentration (5.3 +/- 1.8 SD vs 7.1 +/- 2.7 NG/mg; F = 4.34, P = 0.04). During follow-up the prothrombin time was prolonged (F = 4.34, P = 0.04) and leukocyte count decreased (F = 7.39, P < 0.019) in the APV patients, whereas fibrinogen, D-dimer, lipoprotein(a), and folate were unchanged. CONCLUSION: Our results provide evidence suggesting an involvement of the hemostatic system in APV.

Acute Disease↗

Hemostatic effects of tranexamic acid in elective thoracic aortic surgery: a prospective, randomized, double-blind, placebo-controlled study.

OBJECTIVE: We studied the hemostatic effects of tranexamic acid in patients undergoing elective surgery involving the thoracic aorta. METHODS: In a double-blind, randomized fashion, 60 consecutive patients were assigned to two treatment groups: 30 patients (placebo group) received infusion of saline solution, and 30 (treatment group) received tranexamic acid (1 g before skin incision, an infusion of 400 mg/h during the operation, and 500 mg in the pump priming). Perioperative bleeding was considered as a primary outcome. Perioperative allogeneic transfusions, major thrombotic complications (myocardial infarction, pulmonary embolism, renal insufficiency), and surgical outcomes were also considered. RESULTS: Patients treated with tranexamic acid showed significant reductions in postoperative bleeding, both in terms of the amount collected during the first 4 postoperative hours (median 307 mL, interquartile range 253-361 mL in the placebo group vs median 211 mL, interquartile range 108-252 mL in the treatment group, P =.002) and in terms of total bleeding (median 722 mL, interquartile range 574-952 mL in the placebo group vs median 411 mL, interquartile range 313-804 mL in the treatment group, P =.04). Consequently, the number of patients transfused differed significantly between groups (21 patients [72.4%] in the placebo group vs 13 [44.8%] in the treatment group, P =.033). Patients in the treatment group showed significant reductions in the total amount for the entire group of packed red cells transfused (13,500 mL in the treatment group vs 28,000 mL in the placebo group, P =.012) and in the total amount of allogeneic transfusions (23,400 mL in the treatment group vs 53,000 mL in the placebo group, P =.024). No differences in perioperative thrombotic complications were found. CONCLUSIONS: In this initial series of patients undergoing thoracic aortic surgery, tranexamic acid appeared effective in reducing perioperative bleeding, with a significant reduction in the need for allogeneic transfusions and without any increased risk of thrombotic complications.

Aged↗

Hemostatic markers before operation in patients with acutely symptomatic nonruptured and ruptured infrarenal abdominal aortic aneurysm.

BACKGROUND: In patients with acutely symptomatic but nonruptured abdominal aortic aneurysm (AAA), emergent repair is associated with an increased mortality rate as compared with semi-elective repair. Previous results have shown that ruptured but not asymptomatic AAA repair is associated with intense thrombin generation and inhibition of systemic fibrinolysis. The purpose of this study was to determine whether circulating markers of coagulation and fibrinolysis may be used to distinguish acutely symptomatic nonruptured and ruptured AAA. METHODS: A prospective study was performed of 44 patients who underwent emergency AAA repair for suspected rupture. Platelet count, fibrinogen level, prothrombin time, activated partial thromboplastin time, tissue plasminogen activator (t-PA) activity, plasminogen activator inhibitor (PAI) activity, prothrombin fragment (PF) 1+2 level, and D dimer level were measured before surgery. RESULTS: When compared with ruptured AAAs (n = 37), acutely symptomatic nonruptured AAAs (n = 7) were associated with increased fibrinogen level (P =.033), reduced activated partial thromboplastin time (P =.043), increased t-PA activity (P =.023), reduced PAI activity (P =.005), reduced PF 1+2 level (P =.001), and reduced D dimer level (P =.005; all P values determined with Mann-Whitney test). The differences in t-PA activity (P =.01), PAI activity (P =.004), and PF 1+2 level (P =.01) persisted in patients whose conditions were normotensive. In all patients, a PF 1+2 level of greater than or equal to 2.5 nmol/L was associated with a sensitivity, specificity, and positive and negative predictive value for rupture of 89%, 86%, 97%, and 60%, respectively. In patients whose conditions were normotensive, PAI activity of greater than or equal to 16 AU/mL was associated with a sensitivity, specificity, and positive and negative predictive value of 83%, 100%, 100%, and 88%, respectively. CONCLUSION: These data show that acutely symptomatic nonruptured AAA is associated with increased systemic fibrinolysis (caused by reduced fibrinolytic inhibition) and reduced thrombin generation as compared with rupture. Preoperative hemostatic markers, particularly PF 1+2 level and PAI activity, may distinguish acutely symptomatic nonruptured from ruptured AAA.

Aged↗

Effects of low-dose oral and transdermal estrogen replacement therapy on hemostatic factors in healthy postmenopausal women: a randomized placebo-controlled study.

OBJECTIVE: This study was undertaken to investigate the effect of transdermal and oral estrogen replacement therapy in healthy postmenopausal women on markers of coagulation and fibrinolysis associated with coronary artery disease. STUDY DESIGN: In a randomized, placebo-controlled, double-blind study, healthy hysterectomized postmenopausal women received daily either placebo (n=49), transdermal 17beta-estradiol (E(2)) 50 microg (tE(2) group, n=33), oral E(2) 1 mg (oE(2) group, n=37), or oral E(2) 1 mg combined with gestodene 25 microg (oE(2)+G group, n=33) for thirteen 28-day treatment cycles. Hemostatic variables were measured in blood samples collected at baseline and in cycles 4 and 13. RESULTS: No significant changes versus baseline and placebo were found in the tE(2) group, except for plasminogen activator inhibitor type-1 (PAI-1) in cycle 13 (-32.4%, P=.01). In the oE(2) group, significant percentage changes from baseline versus placebo in cycle 13 were found in fibrinogen, -5.4% (P<.05); factor VII, -7.3% (P<.05); thrombin-antithrombin III complexes, -13.3% (P<.05); tissue-type plasminogen activator (t-PA), -17.3% (P<.001); and PAI-1, -54.3% (P<.001). In the oE(2)+G group, respective changes were factor VII, -17.6% (P<.001); t-PA, -14.5% (P=.01); PAI-1, -36.4% (P<.01); and D-dimer, +21.8% (P<.05). No significant changes were observed in prothrombin fragment 1+2 and plasmin-alpha(2)-antiplasmin complexes. CONCLUSION: Low-dose oral estradiol therapy was associated with an increase in fibrinolysis and small decreases in procoagulant variables. Transdermal therapy had minor effects.

Administration, Cutaneous↗