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Disorders of Hemostasis
Thromboembolic disorders and bleeding disorders are two types of disruptions in hemostasis.
The thromboembolic disorders are characterized by the formation of an undesirable blood clot or thrombus in an unbroken vessel.
Such clots can be caused by conditions that roughen endothelium, such as arteriosclerosis, infection, or trauma.
Sluggish blood flow through narrow blood vessels or in bedridden patients can also prompt procoagulant accumulation.
The resulting blockade can cause ischemic tissue damage or dislodge emboli to other body parts, causing complications like organ damage, stroke, or heart attack.
Alternatively, impaired blood clotting mechanisms can cause bleeding disorders.
Vitamin K deficiency affects the production of clotting factors by the liver, specifically prothrombin, Factors VII, IX, and X.
Conditions like bone marrow diseases and drug toxicity can cause a low platelet count or thrombocytopenia, leading to spontaneous bleeding from small blood vessels and purplish spots on the skin.
Hemophilias are hereditary bleeding disorders resulting from the lack of clotting factors. Based on the deficient clotting factor, they are classified as hemophilia A, B, and C.
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Disorders of Hemostasis
Hemostasis, the process that stops bleeding after a blood vessel injury, is crucial for maintaining the integrity of the circulatory system. However, disorders of hemostasis can disrupt this delicate balance, leading to either excessive clotting or bleeding. These disorders can be broadly classified into thromboembolic disorders and bleeding disorders.
Thromboembolic Disorders
Two factors primarily cause thromboembolic conditions.
- The first is the irregular texture of blood vessels, which can result from arteriosclerosis, infection, or injury.
- The second factor is the slow flow of blood through vessels, which can promote thrombin formation and other procoagulants.
Thromboembolic disorders are characterized by the formation of a blood clot or thrombus in a blood vessel. This clot can block blood flow and cause tissue ischemia, which can damage organs and increase the risk of severe health events like stroke or heart attack.
A thrombus becomes an embolus when it dislodges and travels through the bloodstream. This embolus can obstruct blood flow in other areas of the body, potentially leading to life-threatening conditions such as pulmonary embolism or stroke.
Bleeding Disorders
On the other end of the spectrum, bleeding disorders result from impaired blood clotting, leading to excessive bleeding. These disorders can arise from various causes, including vitamin K deficiency, hemophilia, and thrombocytopenia.
- • Vitamin K deficiency can impair the production of proteins necessary for blood clotting, specifically prothrombin, Factor VII, Factor IX, and Factor X. This deficiency can lead to prolonged bleeding and easy bruising.
- • Hemophilia, particularly hemophilia A, is another bleeding disorder caused by an abnormality or deficiency of Factor VIII. This X-linked genetic disorder primarily affects males and can result in excessive bleeding, even from minor injuries.
- • Thrombocytopenia is characterized by a low number of platelets – the blood cells responsible for forming clots to stop bleeding. This condition can result from various causes, including developing antibodies that destroy platelets. Thrombocytopenia can lead to a tendency to bleed from small vessels and capillaries. Treatment may include fresh whole blood transfusions or splenectomy.