Quiz 38: Pharmacotherapy of Coagulation Disorders
Coumarin (Warfarin) is a synthetic anticoagulant drug which acts by preventing the clot formation in the blood. The patient with atrial fibrillation has alterted rhythm of their heart that increases the chances of clot formation in their coronary arteries and other vessels. Thus, the warfarin here is given to the patient of atrial fibrillation to prevent clot formation and hence, the chances of stroke.
Coagulation is the process in which the blood coverts from liquid to semisolid form forming clot. It occurs only when the blood leaks out from a vessel or it may also occur inside the vessel when the blood becomes thick due to some deficiency. The coagulation process at the end forms fibrin (thread like material) which forms a mesh at the leakage point and blocks the blood cells to move out of the vessel. This mesh along with the blood cells and dead bacteria is known as clot. There are two ways of formation of clot and these are intrinsic and extrinsic pathway. These are as follows: It gets clear from the above given flowchart that it is the intrinsic pathway that activates during leak from a vessel as it is mentioned that it starts by stimulation from a damaged surface. Also, the more complex pathway is also the intrinsic pathway as it is shown above. Thus, being complex, the intrinsic pathway will take several minutes to form clot. It is vivid from the flowchart that at the stage of factor X, both the pathways then follow the same route and they form a common pathway. Thus, it is observed that at the end fibrin clot is formed and is formed from each pathway as both unite to form a common pathway. Hence, both the pathways result in the formation of fibrin.
The patient will be said that the Heparin is an anticoagulant. The word anticoagulant means the process that prevents the coagulation to occur. Thus, the drug heparin will only prevent other clots to form. This will not dissolve the existing clot. The treatment will be done by first preventing more clots to form and then dissolving the existing clot. Thus, the patient will be consoled that not to worry and the clot will soon be dissolved and to have patience and relax. The exertion could pose bad effect on the heart.