A blood clot that forms within a vessel and stays attached where it formed is called a thrombus.
Missing Word
thrombus
A thrombus is a stationary clot inside a blood vessel or heart chamber. It can narrow or block blood flow at that site, and a piece of it may break off and travel.
Category: Clotting Physiology
Question 2
A detached clot that travels in the bloodstream, such as one moving from a leg vein to the lungs, is called an embolus, while the blockage it causes is an embolism.
Missing Word
embolus
An embolus is material, usually a clot, that moves through the circulation until it lodges in a smaller vessel. A deep vein clot that travels to the lungs causes a pulmonary embolism.
Category: Clotting Physiology
Question 3
Exposed collagen in a damaged vessel wall activates factor XII to start the intrinsic coagulation pathway.
Missing Word
collagen
Collagen is the structural protein beneath the endothelium. When injury exposes it, platelets adhere and factor XII is activated, launching the intrinsic pathway.
Category: Clotting Physiology
Question 4
Glycoprotein IIb/IIIa receptors on platelets bind fibrinogen and von Willebrand factor, linking platelets together into a plug.
Missing Word
fibrinogen
Fibrinogen is a plasma protein that bridges activated platelets through their glycoprotein IIb/IIIa receptors and is later converted to fibrin. Drugs such as eptifibatide block this binding.
Category: Clotting Physiology
Question 5
The overall process that stops bleeding through vessel constriction, platelet plug formation and coagulation is called hemostasis.
Missing Word
hemostasis
Hemostasis is the body's response to vessel injury: the vessel narrows, platelets form a plug, and the clotting cascade builds a fibrin clot. Anticoagulant, antiplatelet and thrombolytic drugs each act on a different part of this process.
Category: Clotting Physiology
Question 6
Patients taking warfarin are taught to abstain from alcohol, a drink that can make the INR unpredictable and raise the risk of bleeding.
Missing Word
alcohol
Alcohol alters liver metabolism of warfarin and can make the INR unpredictable, and heavy drinking also raises the risk of falls and GI bleeding. Patients are also taught to ask a pharmacist before using herbal products such as ginkgo, garlic or St. John's wort.
Category: Warfarin
Question 7
Vitamin K used to reverse warfarin is given under the generic name phytonadione.
Missing Word
phytonadione
Phytonadione is vitamin K1, which allows the liver to make functional clotting factors again. It can be given orally or IV and should never be confused with potassium, whose symbol is also K.
Category: Warfarin
Question 8
Aspirin blocks cyclooxygenase in platelets and so reduces their production of thromboxane, a substance that activates platelets.
Missing Word
thromboxane
Thromboxane A2 is made by platelets and promotes their activation and aggregation. Aspirin blocks its production for the life of the platelet, which is the basis of its antiplatelet effect.
Category: Antiplatelets
Question 9
Unlike clopidogrel and prasugrel, the oral P2Y12 inhibitor ticagrelor binds its receptor reversibly.
Missing Word
ticagrelor
Ticagrelor blocks the P2Y12 receptor reversibly, while clopidogrel and prasugrel bind it permanently for the life of the platelet. Ticagrelor is also active without liver conversion, and like the others it raises the risk of bleeding.
Category: Antiplatelets
Question 10
Clopidogrel is a prodrug, meaning liver enzymes must convert it to an active form before it can block platelets.
Missing Word
prodrug
A prodrug is given in an inactive form and becomes active only after metabolism. Because clopidogrel depends on this step, genetic differences and interacting drugs can reduce its effect.
Category: Antiplatelets
Question 11
Coughing up blood, called hemoptysis, is a warning sign of bleeding in a patient taking an anticoagulant.
Missing Word
hemoptysis
Hemoptysis is the expectoration of blood from the respiratory tract. In an anticoagulated patient it signals possible bleeding in the lungs or airway and is reported promptly.
Category: Bleeding Precautions
Question 12
A nosebleed, or epistaxis, can be a sign of excessive anticoagulation.
Missing Word
epistaxis
Epistaxis is bleeding from the nose. Frequent or prolonged nosebleeds in a patient on an anticoagulant suggest excess drug effect and are reported to the provider.
Category: Bleeding Precautions
Question 13
Blood in the urine, called hematuria, is a bleeding warning sign that patients on anticoagulants should report.
Missing Word
hematuria
Hematuria is the presence of blood in the urine, which may look pink, red or brown. In an anticoagulated patient it can indicate bleeding in the urinary tract.
Category: Bleeding Precautions
Question 14
Pinpoint red or purple spots on the skin caused by tiny bleeds under its surface are called petechiae.
Missing Word
petechiae
Petechiae are flat, pinpoint hemorrhages from small capillaries. Their appearance in a patient on anticoagulant or antiplatelet therapy, or with a falling platelet count, should be reported.
Category: Bleeding Precautions
Question 15
When a thrombolytic opens a blocked coronary artery, the return of blood flow, called reperfusion, can trigger dysrhythmias.
Missing Word
reperfusion
Reperfusion is the restoration of blood flow to tissue that was ischemic. After thrombolysis for an MI, reperfusion dysrhythmias can occur, so the patient stays on continuous cardiac monitoring.
Category: Thrombolytics