Hypercoagulability, blood

Hypercoagulability, blood, 330 Hyperkinetic children, 88 Hyperthyroidism, 240 Hypoglycemia, 136 Hypothyroidism, 95... 

Patients with HF are at an increased risk of thromboembolic events secondary to a combination of hypercoagulability, relative stasis of blood, and endothelial dysfunction. However, the role of antiplatelets and anticoagulants remains debatable due to a lack of prospective clinical trials. 

Hypercoagulable states, in turn, have been traditionally associated with venous thrombosis. Consequently, attention has been paid to alterations of the hemostatic balance. Although this is a systemic variable, focality is favored due to the contribution of decreased blood flow, as confirmed by the preferential development of venous thrombi at the level of valves, an area of stasis where low-velocity flow is moderately turbulent. 

The prevention of excessive blood loss through breaches of the vascular barrier is important to maintain oxygen delivery and blood volume. A fall in blood volume would cause a drop in blood pressure and the metabolism of all of the major organs would be badly affected. Failures of the haemostatic mechanisms can lead to haemorrhage (bleeding disorders) or thrombosis (hypercoagulation disorders). 

The considerable body of evidence that glucocorticoids can cause increased rates of vascular mortality and the underlying mechanisms (increased blood pressure, impaired glucose tolerance, dyslipidemia, hypercoagulability, and increased fibrinogen production) have been... 

I 99 Fareed D, Bick R, Bacher P et al, Blood levels of nitric oxide, C-reactive protein and TNF-a are upregulated in patients with malignancy-associated hypercoagulable state pathophysiologic implications. Pathophysiol Haemost Thromb 2003 33(suppl I ) 69—76. 

Q8 Risk factors for stroke include hypertension, hyperlipidaemia, hypercoagulability of blood, sluggish blood flow (e.g. following surgery or myocardial infarction) and atherosclerosis. All these predispose patients to stroke. Age could also be included here as the incidence of thromboembolism increases in those over 50 years of age. 

Q6 A thrombus is a blood clot which is fixed to the blood vessel wall. When it detaches and is carried in the blood, it is known as an embolus. Both thrombi and emboli can block blood vessels and deprive tissues of oxygen. In arteries blood clots usually form because the inner surface has been altered by deposition of atheroma. In contrast venous thrombosis results from slow or stagnant blood flow in veins, or defects in mechanisms which normally oppose inappropriate coagulation. Three major risk factors for pulmonary embolism are (i) venous stasis, (ii) hypercoagulability ofblood and (iii) injury to vascular endothelium following trauma or plaque rupture. 

Homocysteine-lowering treatment with folic acid, cobalamin and pyridoxine does not reduce blood markers of inflammation, endothelial dysfunction or hypercoagulability in patients with previous transient ischemic attack or stroke a randomized substudy of the VITATOPS trial. Stroke 36 144-146... 

A very few cases of ciclosporin-induced immune hemolytic anemia have been reported (SED-13, 1125) (69,70), but a direct causal relation with ciclosporin is difficult to establish. Ciclosporin-induced hypercoagulability was suggested in patients with aplastic anemia (SEDA-20, 344). Higher whole-blood ciclosporin concentrations were found during the preceding months in patients who... 

Vascular access thrombosis has been reported in up to 26% of patients treated with epoetin alfa (3,34,38). Most of the failures occurred in poljdetrafluoroethylene grafts. There was no comparison with patients not treated with epoetin. It has been suggested that the increased risk of extracorporeal circuit clotting and the higher heparin requirements during hemodialysis may not be due to a hypercoagulable state, but rather to an increase in erythrocyte mass and consequently in whole blood viscosity (66). 

Markers of blood hypercoagulability (e.g., fibrinogen, D-dimer, and factor V Leiden)... 

Hematology Does the patient have a blood dyscrasia attributable to antiepileptic drugs or other medications Is the patient hypercoagul-able, causing an increased risk of stroke Does the patient have any particular bleeding risk that limits antiplatelet drug use ... 

Heparin therapy for DIG is discouraged by most clinicians because there is no evidence that heparin prolongs the survival of patients despite its effect on the hypercoagulable condition found in DIG. Hemorrhage is best managed by the replacement of clotting factors, platelets, and packed red blood cells. 

It seems likely that hypercoagulability of blood is related to the levels of activated coagulation factors and not to the total quantities of unactivated factors present As such activated factors are rapidly cleared from the blood, and as the process of thrombus formation is in dynamic equilibrium with thrombolysis, it has not yet been possible to define rigidly that concatenation of circumstances that leads to macroclot formation, or to be certain that the changes in coagulation factors induced by the pill are, per se, directly responsible for thrombembolic episodes attributed to this medication. As mentioned elsewhere [264], their role may be both causative and permissive. 

Co riff SW, Diefenbach AF, Vogt W. Hypercoagulability of tiie blood associated with ACTH and cortisone tiierapy. Am JMed (1950) 9, 752-6. 

The authors suggested that thrombus had formed from a combination of the effects of prothrombin complex concentrate, desmopressin acetate, which releases von Will-ebrand factor and factor VIII from endothelial cells, and blood stasis of on re-expansion of the right ventricle following pericardiocentesis, creating a hypercoagul-able state. The failure of the prothrombin complex concentrate to correct the INR was probably due to consumption of the active factors by the ventricular thrombus. 

Emani S, et al. Novel microfluidic platform for automated lab-on-chip testing of hypercoagulability panel. Blood Coagul Fibrinolysis 2012 23 760-8. 

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