BIOS 255 Week 1 Case Study-Coagulation

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Week 1 Case Study: Coagulation

Chamberlain University

BIOS 255-13465

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Discuss which clotting factors the PT and PTT test evaluate


and whether each test measures the intrinsic or the


extrinsic pathways.


According to this website, “The PTT assesses the amount and the function of


certain proteins in the blood called coagulation or clotting factors that are an


important part of blood clot formation” (Expert Board, 2021). The clotting factors for


a PT test include VII, X, V, II, and I (fibrinogen). This test measures the extrinsic


pathways. As for PTT, this test evaluates factors XII, XI, VIII, IX and measures


intrinsic pathways.


Describe the common coagulation pathway.


The common coagulation pathway consists of a series of events that all lead up to


hemostasis. The two paths known as extrinsic and intrinsic, happen at separate times


but come together at a certain point leading to fibrin activation. The common pathway


factors consist of factors I, II, V, VIII, X. This pathway begins at factor X, which is


then activated to factor XA. Once XA is activated, prothrombin and then thrombin are


activated.


Based on Jessie’s test, which factor deficiency do you


believe he has and why?