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At least 271 records · Page 15Linked to original sources
PubMed1996

Endothelial effects of hemostatic devices for continuous cardioplegia or minimally invasive operations.

BACKGROUND: Improvements in myocardial protection may include the continuous delivery of normothermic blood cardioplegia. Technical aids are required for optimal visualization of the operative field during the performance of coronary anastomoses if cardioplegia is to be given continuously or during minimally invasive operations. However, the effects of the different hemostatic devices on coronary endothelial function are unknown. METHODS: We compared the effects on endothelial function of two commonly used hemostatic techniques, coronary clamping and gas jet insufflation, with those of a technique using extravascular balloon occlusion to mimic systolic luminal closure by the surrounding myocardium. The three techniques were applied for 15 minutes on porcine epicardial coronary arteries from explanted hearts. For coronary clamping, standard bulldog clamps were used. Gas jet insufflation was applied by blowing oxygen (12 L/min) tangentially at a 45-degree angle 1 cm away from a 3-mm arteriotomy. Extravascular balloon occlusion was achieved with a needle-tipped silicone loop, the midportion of which, once positioned beneath the coronary artery, was inflated to push a myocardial "cushion" against the back of the vessel until its occlusion. Control rings were taken from the same coronary artery. The endothelial function of control and instrumented arterial rings was then studied in organ chambers filled with modified Krebs-Ringer bicarbonate solution. RESULTS: Contractions to potassium chloride and prostaglandin F2 alpha and endothelium-independent relaxation to sin-1, a nitric oxide donor, were unaffected in all groups. Endothelium-dependent relaxation to serotonin was impaired after clamping and preserved after gas jet insufflation and extravascular balloon occlusion. Maximal endothelium-dependent relaxation to serotonin was as follows: for coronary clamping, 63% +/- 6% versus 87% +/- 3% in controls; for gas jet insufflation, 67% +/- 12% versus 88% +/- 7%; and for extraluminal balloon occlusion, 79% +/- 6% versus 85% +/- 5%. CONCLUSIONS: Whereas commonly used hemostatic devices may impair endothelial function, extravascular balloon occlusion appears to achieve effective hemostasis while preserving endothelial integrity.

Animals↗
PubMed1996

A comparative study of the effects of the hemostatic system of two monophasic gestodene oral contraceptives containing 20 micrograms and 30 micrograms ethinylestradiol.

The effects of two oral contraceptives, containing gestodene and either 20 micrograms or 30 micrograms ethinylestradiol, on hemostatic parameters was investigated in a six-month randomized study involving a total of 40 healthy women between the ages of 18 and 30 years. A large number of hemostatic parameters were measured, which were categorized as either pro-coagulatory, anti-coagulatory, profibrinolytic, anti-fibrinolytic or indicative of fibrin turnover. Additionally, tissue plasminogen activator (t-PA) and plasminogen activator inhibitor (PAI-1) were measured before and after venous occlusion and delta and ratio values calculated. Pro-coagulatory factors as well as reaction products reflecting in vivo coagulatory activity (thrombin-antithrombin III complex, prothrombin fragment 1 + 2) were found to increase. Among the anti-coagulatory parameters, only protein S concentration and protein S activity decreased, most notably in the 30 micrograms EE group. There was a corresponding increase in fibrinolytic activity reflected by reaction products of in vivo fibrinolysis (plasmin-antiplasmin 2-complex, fibrin-degradation products). Measurement of t-PA and PAI-1, before and after venous occlusion, revealed that the fibrinolytic response was more pronounced in the 20 micrograms EE group. There was also an increase in the threshold of fibrinolytic inhibition (ratio PAI-1) in both groups, which was less pronounced in the 20 micrograms EE group. Apart from isolated measurements, all parameters remained within their normal ranges and values returned to baseline in the follow-up cycle. It is concluded that both preparations had a balanced effect on the hemostatic system stimulating both pro-coagulant and fibrinolytic activity. No statistically significant differences were observed between the two groups; however, there was a trend towards greater fibrinolytic capacity in the 20 micrograms EE group.

Adolescent↗
PubMed1991

The PLAT Study: a multidisciplinary study of hemostatic function and conventional risk factors in vascular disease patients.

In this paper are reported the basal results of a multidisciplinary, multicenter study designed to explore in a population with ischemic disease the relation between hemostatic variables, conventional risk factors and atherothrombotic sequelae. 953 patients less than or equal to 69 yrs with documented coronary, cerebral or peripheral atherosclerotic disease were studied and followed-up for 24 months. Examinations included hemostatic and lipid laboratory assays, arterial Doppler examination, cerebral computerized tomography and nuclear magnetic resonance, exercise electrocardiogram and coronary angiography. Fibrinogen (301.4 +/- 71.52 mg/dl) correlated positively with antithrombin III (r = 0.27) and leukocytes (r = 0.25), negatively with HDL-cholesterol (r = 0.18) and tended to increase with smoking. Heavy smokers had higher leukocyte counts than non-smokers (8.0 +/- 2.0 vs. 7.2 +/- 2.1 x 10(3)/microliters), higher triglycerides (1.87 +/- 1.12 vs. 1.53 +/- 1.35 mmol/l) and lower HDL-cholesterol (0.93 +/- 0.27 vs. 1.00 +/- 0.25 mmol/l). FVII correlated positively with triglycerides (r = 0.16) and protein C (r = 0.45). vWF:Ag (145.4 +/- 70.58%) ad FVII:C (139.7 +/- 59.10%) were positively correlated (r = 0.44). FVIII:C correlated positively with fibrinogen (r = 0.21). Myocardial infarction survivors with associated cerebral and peripheral vascular lesions had higher FVIII:C, FVII, fibronogen and vWF:Ag. These findings suggest that hemostatic factors may enhance and/or mediate the effects of conventional risk factors in atherothrombotic ischemic events.

Aged↗
PubMed1996

Effect of Habu (Trimeresurus flavoviridis) antivenom on changes of hemostatic parameters following administration of crude venom from T. flavoviridis in rabbits.

We carried out experiments to examine the efficacy of Habu antivenom in relation to variations of hemostatic parameters induced by the administration of crude venom to rabbits. For neutralization of the crude venom by Habu antivenom, the correlation between the concentrations of Habu antivenom (Y) and crude venom (X) was expressed by the equation: Y = -0.473 + 0.539X. We examined the variations in hemostatic parameters in the state which crude venom was neutralized by Habu antivenom following the administration of crude venom (1 mg/kg) from Trimeresurus flavoviridis. Although the hemostatic parameters [level of fibrinogen, antithrombin III (AT-III) activity and alpha 2-plasmin inhibitor (alpha 2-PI) activity] underwent decreases after the administration of crude venom, they revealed fluctuations within the normal range after the Habu antivenom administration. The AT-III activity, however, decreased gradually until 90 min after the antivenom administration. These results suggested that Habu antivenom was effective in improving the abnormal coagulant activity induced by crude venom. However, the neutralization effect towards the coagulant activity of crude venom by the Habu antivenom did not continue for a long time and did not lead to recovery of the AT-III activity. Since excessive doses of antivenom can induce serious medical problems, we expect that simultaneous use of antivenom and AT-III preparation, instead of excessive and single use of Habu antivenom could provide a useful therapy for snake bites from the present study.

Animals↗
PubMed1983

The effect of aspirin on the size of the hemostatic plug.

The prolongation of the bleeding time by aspirin is presumably due to interfering with platelet function. Direct quantitative studies evaluating the effects of aspirin on the platelet component of the hemostatic plug have not been described. We measured blood loss from a standard ear injury in rabbits after treatment with either 5 mg or 200 mg/kg of aspirin (ASA) or sodium salicylate (SA), and related this observation to the number of platelets incorporated into the hemostatic plug. The high dose of aspirin was chosen since this dose inhibits PGI2 biosynthesis. Both doses of aspirin but not salicylate caused a significant increase on blood loss from the treated ear compared to the control (ASA 5 mg/kg, 0.012 +/- 0.009 ml, (m +/- SE), n = 44, p = 0.03; ASA 200 mg/kg, 0.02 +/- 0.007 ml, n = 17, p less than 0.05). Both doses of aspirin also caused a significant increase in the number of platelets incorporated into the hemostatic plug when compared to the SA treated animals (ASA 5 mg/kg, 3.52 +/- 0.34 X 10(6) platelets per incision, (m +/- SE), n = 59; SA 5 mg/kg, 1.9 +/- 0.15 X 10(6) platelets per incision, n = 54, p less than 0.001; ASA 200 mg/kg, 3.19 +/- 0.54 X 10(6) platelets per incision, n = 22; SA 200 mg/kg, 1.5 +/- 0.26 X 10(6) platelets per incision, n = 23, p less than 0.001). This study suggests that following aspirin administration hemostasis is achieved by the incorporation of a greater number of platelets into the platelet plug.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1990

The effects of acute exercise and increased atmospheric pressure on the hemostatic mechanism and plasma catecholamine levels.

The hemostatic response to acute exercise and increased atmospheric pressure was studied in 20 healthy male subjects (18-35 yr of age) exercised to volitional exhaustion on a cycle ergometer in a hyperbaric chamber at 3 atmospheres absolute (ATA). As a means of comparison, 6 of the 20 subjects were exercised in the same manner at 1 ATA. Similar increases in fibrinolytic activity (FA), Factor VIII activity (VIII:C), von Willebrand factor antigen (vWF:Ag) and plasma catecholamine levels were observed following acute exercise at 1 ATA and at 3 ATA. There were no changes in the levels of plasminogen, antithrombin III, Protein C or Fibrinopeptide A (FPA) with exercise either at 1 ATA or at 3 ATA. In addition, there were no changes in plasma catecholamine levels or any of the hemostatic variables measured when atmospheric pressure was increased from 1 ATA to 3ATA without exercise. These findings demonstrate that increasing atmospheric pressure from 1 ATA to 3 ATA does not alter the exercise-induced changes in hemostasis. Therefore, exercise or physical exertion at 3 ATA for a time period not to exceed 30 min does not perturb the hemostatic mechanism and increase the risk of bleeding or thrombosis.

Adolescent↗
PubMed1992

An animal model of fibrinolytic bleeding based on the rebleed phenomenon: application to a study of vulnerability of hemostatic plugs of different age.

The primary bleeding time is prolonged when tested during the infusion of both plasminogen activators and anticoagulants, and such sites frequently exhibit rebleeding after initial hemostatic control. This study describes an animal (rabbit) model which distinguishes fibrinolytic from anticoagulant hemorrhage and further applies the model to the study of hemostatic plugs of increasing age. In this model, rebleeding occurred from hemostatically-stable ear puncture sites induced prior to infusion of streptokinase (SK) or recombinant tissue-plasminogen activator (rt-PA), but not of heparin or hirudin. This distinction was apparent even for lesions induced only 15 minutes prior to the infusion and fibrinolytic bleeding was observed in such lesions induced up to 24 hours earlier. Post-infusion sites bled more quickly than did pre-infusion sites, and there was a gradual decrease in susceptibility of such prior trauma sites for rebleeding, evidenced not only by a lower proportion of sites that rebled, but also by a longer lag time after starting SK or rt-PA before such rebleeding occurred. At the dosages tested, SK showed a trend (not statistically significant) toward more sites that rebled, while rt-PA showed a trend towards a longer duration of rebleeding. Thus, this animal model of rebleeding appears to be unique for fibrinolytic agents and allows for more detailed study of the physiological mechanisms of such bleeding and for a multifaceted comparison of the bleeding potential of plasminogen activators.

Animals↗
PubMed1984

Toxicological assessment of the hemostatic system, regulatory requirements, and industry practice.

Disturbances of the hemostatic system which may be caused by chemicals include hemorrhagic diathesis, caused by inhibition of blood clotting, impairment of platelet function, and hyperactivity of fibrinolysis. Activation of the plasmatic clotting system, platelet aggregation, and inhibition of fibrinolysis may lead to thromboembolic complications. Although much is known about the functions of the hemostatic system a rational and cost-effective approach for its assessment in industrial toxicology is lacking. In this review the physiology of hemostasis and the available laboratory tests are discussed, current regulatory requirements are described, and industry practice is analyzed based on experience accumulated over the last 23 years. Proposals for a more flexible and scientific approach to testing of hemostatic mechanisms in toxicology are made.

Animals↗
PubMed1995

Hemostatic concomitants of syndrome X.

The elevated risk factors classically associated with Syndrome X do not adequately explain the increased cardiovascular risk linked to insulin resistance. Considerable indirect evidence and more limited direct evidence suggests that increases in certain prognostically significant hemostatic variables--notably plasma fibrinogen, factor VII coagulant activity, and plasminogen activator inhibitor-1 levels--may be concomitants of Syndrome X. Increased platelet aggregability, and a reduced capacity of vascular endothelium for prostacyclin generation, may also be associated with insulin resistance. Large clinical studies, involving quantification of insulin sensitivity and measurement of hemostatic variables, are required to test this hypothesis. It is unlikely that hyperinsulinemia mediates the connections between insulin resistance and hemostatic variables (or indeed other risk factors in Syndrome X). In light of the remarkably broad impact of insulin resistance on cardiovascular risk factors, promotion of optimal insulin sensitivity should assume a central role in preventive cardiology.

Animals↗
PubMed1992

Hemostatic factors according to menopausal status and use of hormone replacement therapy.

The rise in cardiovascular disease (CVD) risk after menopause may be reduced by hormone replacement therapy (HRT) although the mechanism is unclear. Because little is known about the potential role of hemostatic factors, fibrinogen level and other coagulation parameters were measured in a study on the change in CVD risk factors through the climacteric (the Healthy Women Study). Of 239 subjects measured to date, 32 taking aspirin or other medications thought to alter coagulation were excluded from analyses. Results (adjusted for age and obesity) showed that women taking HRT had lower plasma concentrations of fibrinogen and higher levels of plasminogen and factor VIIc than did postmenopausal subjects not taking HRT. Pre- as compared with postmenopausal women had lower plasma levels of fibrinogen, factor VIIc, and antithrombin III. Adjusting for cigarette smoking did not change the findings. Thus, among women aged 49 to 55, selected hemostatic measures varied (within normal ranges) by menopausal status and were altered by HRT. These findings generally support a hypothesis of hemostatic change contributing to the increase of CVD after menopause. The fact that subjects taking HRT showed no increase in fibrinogen relative to premenopausal women is consistent with an observed decreased risk of CVD among women taking HRT, while the implication of an elevation in factor VIIc among these women is uncertain.

Antithrombin III↗
PubMed2005

Effects of two combined oral contraceptives containing ethinyl estradiol 20 microg combined with either drospirenone or desogestrel on lipids, hemostatic parameters and carbohydrate metabolism.

OBJECTIVE: To compare the effect of ethinyl estradiol 20 microg/drospirenone 3 mg (EE 20 microg/DRSP 3 mg) administered according to a 24/4 regimen with ethinyl estradiol 20 microg/desogestrel 150 microg (EE 20 microg/DSG 150 microg) administered according to the conventional 21/7 regimen on lipid, carbohydrate and hemostatic parameters. STUDY DESIGN: In this open-label study, healthy women were randomized to EE 20 microg/DRSP 3 mg or EE 20 microg/DSG 150 microg for seven cycles. Mean differences in high-density lipoprotein (HDL)- and low-density lipoprotein (LDL)-cholesterol levels at cycle 7 compared to baseline were assessed. Secondary variables included changes in other lipid, hemostatic and carbohydrate parameters. RESULTS: Both treatments increased HDL-cholesterol, but decreased LDL-cholesterol by a comparable extent. Although slightly elevated in both groups, blood glucose and C-peptide levels measured during oral glucose tolerance tests were within normal reference ranges at cycle 7. Overall, the differences in lipid, hemostatic or carbohydrate parameters were not significant between the two treatments. CONCLUSION: EE 20 microg/DRSP 3 mg has a good safety profile comparable with EE 20 microg/DSG 150 microg.

Adult↗
PubMed2005

Postprandial activation of hemostatic factors: role of dietary fatty acids.

Intake of dietary fat is an important determinant of the plasma concentration of triacylglycerol-rich lipoproteins, and the degree of alimentary lipemia is reported to have effects on hemostatic status including platelet function. Although association between the amount of dietary fat intake, lipemic response and certain cardiovascular disease (CVD) risk factors (VIIa and PAI-1) has been reported, the significance of the fatty acid composition of ingested fat for the postprandial lipid concentrations and the hemostatic factors is still unclear. Accumulating evidence suggests a relationship between dietary fatty acids and emerging hemostatic CVD risk factors, although much of this evidence is incomplete or conflicting. In order to improve our knowledge in this area, sufficient sample size in future studies are required to take into account of the genetic variation (gene polymorphisms for VII, PAI-1), sex, physical activity, stage of life factors, and sufficient duration to account for adaptation for definitive conclusions.

Cardiovascular Diseases↗
PubMed2004

Prognostic significance of hemostatic parameters in patients with lung cancer.

There is a subclinical activation of coagulation and fibrinolysis system in lung cancer. Alterations in hemostatic system are seen frequently in lung cancer correlated with the prognosis of disease. In this prospective study, our purpose was to investigate the prognostic significance of hemostatic markers in patients with lung cancer. The study comprised 58 patients (22 squamous cell carcinoma, 16 adenocarcinoma, 20 small cell carcinoma). There were 55 men (95%)and 3 women (5%) with a mean age of 61 years range (36-74). Plasma level of platelets (PLT), prothrombin time (PT), active partial thromboplastin time (aPTT), antithrombin III (AT III), fibrinogen (F) and D-dimer level were measured before the initiation of any therapy. Patients were followed up for 17 (12-20) months. The median survival was determined as 6.4 months. Three histopathologic groups; squamous cell carcinoma, adenocarcinoma and small cell carcinoma were compared for the hemostatic parameters. There were no statistically significant differences among the histopathologic types for any of the parameters (P > 0.05). Patients were divided into two groups as patients without distant metastasis (stages I,II,III) and with distant metastasis (stage IV). The group with distant metastasis had higher level of D-dimer than the other group (P < 0.05). However, there were no statistically significant differences for D-dimer level between stages IIIB and IV (P > 0.05). Patients having high D-dimer and low AT III level had poor survival in our study. Thus, high level of D-dimer and low AT III level were determined as correlated with short survival (P < 0.05). These results suggest that elevated plasma level of D-dimer and low AT III level might be a sign of poor prognosis in patients with lung cancer.

Adenocarcinoma↗
PubMed2006

Hemostatic status in long-term surviving xenografts.

BACKGROUND: Liver xenotransplantation presents, apart from immunologic problems, metabolic incompatibilities between species. The liver plays a key role in blood coagulation. The aim of this study is to describe the hemostatic status of long-term surviving xenografts in a hamster-to-rat liver xenotransplantation model. METHODS: Orthotopic liver transplantation with Tacrolimus and MMF was carried out with Golden Syrian hamsters, Brown Norway, or Dark Agouti rats as donors and Lewis rats as recipients. Prothrombine time (PT), activated partial thromboplastin time (APTT), antithrombin, protein-C, free protein-S, TAT-complexes, and factors V and VIII were assessed using standard methods. RESULTS: Protein-C was absent in rats, but values in xenotransplanted animals increased progressively toward those recorded in hamsters. Xenotransplanted animals also acquired PT, APTT, free protein-S, and antithrombin levels similar to those of donors and we observed a substantial activation of coagulation especially 7 days post-transplantation. Despite TAT high levels, we did not find thrombotic alterations in the histologic analysis of grafts. CONCLUSIONS: These results reflect a destabilization of the thrombotic-hemostatic balance, not associated with consumption coagulopathy, which gradually disappears. This deregulation is a general imbalance resulting from the replacement of all the components of hepatic synthesis. After 100 days of xenotransplantation, the absence of symptoms of thrombosis or hemorrhage suggests that the change of hemostatic status takes place under conditions of relative equilibrium.

Animals↗
PubMed2005

Effects of short-term glucocorticoids on hemostatic factors in healthy volunteers.

OBJECTIVE: Increased circulating levels of hemostatic factors have been associated with arterial and venous thrombosis. Although in vitro evidence suggests that glucocorticoids may activate hemostasis and inhibit thrombolysis, no controlled in vivo studies have examined the effects of glucocorticoids on hemostatic factors. We hypothesized that a 5-day treatment course of dexamethasone would increase circulating levels of hemostatic and anti-fibrinolytic factors. METHODS: We randomized 24 healthy men ages 19-39 to receive either dexamethasone 3 mg twice daily versus placebo for 5 days. Parameters examined before and after the intervention included: clotting factors VII, VIII, and XI, von Willebrand factor (vWF), D-dimer, PAI-1, soluble CD40-ligand (sCD40-ligand), and fibrinogen. RESULTS: Dexamethasone tended to modestly increase clotting factors levels and fibrinogen without significantly affecting PAI-1, D-dimer or sCD40-ligand. Factor VII increased by a mean of 13% (p = 0.04 versus placebo), factor VIII by 27% (p = 0.0008), factor XI by 6% (p = 0.01), and fibrinogen by 13% (p = 0.05). CONCLUSIONS: Glucocorticoids may increase the activity of clotting factors in vivo. This may contribute to the reported increased risk of thrombosis in patients with sustained exposure to glucocorticoids.

Adult↗
PubMed1995

Predictive value of hemostatic factors for sudden death in patients with stable angina pectoris.

To assess hemostatic risk factors for sudden death in patients with stable angina, 323 consecutive patients were recruited prospectively. Patients with clinical heart failure or recent myocardial infarction were excluded. The following clinical variables were recorded: age, gender, smoking habits, hypertension, previous myocardial infarction, left ventricular hypertrophy, and severe ventricular arrhythmia. Angiographic variables included coronary extent, assessed from Jenkins' and mean atherosclerotic scores, and left ventricular ejection fraction. Lipid variables included total cholesterol, triglycerides, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, and apolipoproteins A-I and B. Hemostatic factors included fibrinogen, fibrinopeptide A, antithrombin III, factor VIII antigen, factor VIII coagulant, protein C, plasminogen, alpha 2 antiplasmin, euglobulin clot lysis time, tissue plasminogen activator before and after venous occlusion, and plasminogen activator inhibitor. There were 34 deaths, 19 of which were sudden during the follow-up period (60 +/- 17 months). The association between each variable and the risk of sudden death was assessed by calculating the relative risk with the Cox univariate model. All significant predictors from the univariate analysis were then incorporated in a Cox multivariate model to select the independent predictors of sudden death. The independent predictors of sudden death were left ventricular hypertrophy (p < 0.04), lower left ventricular ejection fraction (p < 0.04), and shorter euglobulin clot lysis time after venous occlusion (p < 0.02), whereas fibrinogen (p < 0.07) and Jenkins' score (p < 0.08) were borderline. Determination of hemostatic variables, especially those pertaining to dynamic fibrinolysis, may thus be of value in assessing risk of sudden death.

Analysis of Variance↗
PubMed1995

A prospective multicenter evaluation of preoperative hemostatic screening tests. The French Associations for Surgical Research.

BACKGROUND: Several retrospective and four prospective reports have questioned the need for routine preoperative hemostatic screening tests (PHST) in general surgery. PATIENTS AND METHODS: The results of four standard tests (prothrombin time, activated partial thromboplastin time, platelet count, and bleeding time) were prospectively compared with patient history and clinical data in a multicenter study of 3,242 consecutive patients. The patients were divided into four groups: group A (n = 1,951) had no clinical or PHST abnormalities; group B (n = 340) had no clinical and one or more PHST abnormalities; group C (n = 779) had one or more clinical and no PHST abnormalities; group D (n = 172) had both clinical and PHST abnormalities. RESULTS: Preoperative modifications of guidelines (postponed operations and ordering of additional hemostatic tests) were significantly more frequent in both groups of patients with PHST abnormalities (groups B and D), but specific treatment to correct hemostatic disorders was prescribed only when clinical abnormalities were also present (group D). Intraoperatively, modifications of anesthetic and surgical vigilance (planning of increased number of blood units, vascular catheter placement, and number of patients requiring transfusion) were significantly more frequent in group D. Postoperatively, all groups had similar incidences of hematoma or bruises, volumes of blood loss per drainage, reoperations to control hemorrhage, and mortality due to bleeding (n = 5). CONCLUSIONS: Our results suggest that PHST should not be performed routinely, but only in patients with abnormal clinical data. Such a policy necessitates a thorough history--including answers to a specific questionnaire like those used in prospective studies--and a rigorous, well-conducted physical examination.

Adolescent↗
PubMed2001

Mechanisms and attenuation of hemostatic activation during extracorporeal circulation.

Patients undergoing cardiac surgery with cardiopulmonary bypass are at risk for excessive microvascular bleeding, which often leads to transfusion of allogeneic blood and blood components as well as reexploration in a smaller subset of patients. Excessive bleeding after cardiac surgery is generally related to a combination of several alterations in the hemostatic system pertaining to hemodilution, excessive activation of the hemostatic system, and potentially the use of newer, longer-acting antiplatelet or antithrombotic agents. Although several nonpharmacologic strategies have been proposed, this review summarizes the role of pharmacologic interventions as means to attenuate the alterations in the hemostatic system during CPB in an attempt to reduce excessive bleeding, transfusion, and reexploration. Specifically, agents that inhibit platelets, fibrinolysis, factor Xa and thrombin, as well as broad-spectrum agents, have been investigated with respect to their role in reducing consumption of clotting factors and better preservation of platelet function. Prophylactic administration of agents with antifibrinolytic, anticoagulant, and possibly antiinflammatory properties can decrease blood loss and transfusion. Although aprotinin seems to be the most effective blood conservation agent (which is most likely related to its broad-spectrum nature), agents with isolated antifibrinolytic properties may be as effective in low-risk patients. The ability to reduce blood product transfusions and to decrease operative times and reexploration rates favorably affects patient outcomes, availability of blood products, and overall health care costs.

Antifibrinolytic Agents↗