6.1 Anticoagulants

Hemostasis

A general term for any process that stops bleeding

Coagulation

When hemostasis occurs because of the physiological clotting of blood, it is called...

Clots

Insoluble elements of blood, including cells, fibrin threads, that have chemically separated from the liquid component of the blood are called...

Thrombus

The technical term for a blood clot is...

Embolus

A thrombus that is not stationary but moves through blood vessels is called...

Anticoagulants

Substances that inhibit the action of or formation of clotting factors and prevent clot formation

Antiplatelet drugs

Substances that inhibit platelet aggregation and prevent platelet plugs

Thrombolytic drugs

Substances that lyse (break down) existing clots

Hemostatic agents

Substances that promote blood coagulation/arrests the flow of blood

Antifibrinolytic drugs

Hemostatic drugs are also known as...

False

T/F Anticoagulants have an effect on clots that have already formed

Clot formation (thrombus) and dislodged clots (embolus)

Anticoagulants are used prophylactically to prevent which 2 events?

Coagulation cascade

The coagulation system is known as ________ ________ because each activated clotting factor serves as a catalyst that amplifies the next reaction

Fibrin

The result of the coagulation system is _______, a clot forming substance

Intrinsic and Extrinsic

The coagulation system is typically divided into two pathways known as....

Extrinsic

Which pathway is initiated when blood vessels are damaged by penetration from the outside which releases thromboplastin and activates factors VII and X?

Intrinsic

Which pathway is initiated when factor XII comes into contact with exposed collagen on the inside of damaged blood vessels?

The drug/agent

The mechanism of action of anticoagulants vary depending on what?

True

T/F anticoagulants work on different points of the clotting cascade

heparin, low-molecular-weight heparins, warfarin

3 examples of anticoagulants are...

Thromboembolic events

The prevention of clot formation also prevents complications that involve a thrombus becoming an embolus and causing an adverse cardiovascular event known as....

Myocardial infarction

An embolus that lodges in the coronary artery is known as a....

Cerebrovascular accident (stroke)

An embolus that obstructs a brain vessel causes a...

Pulmonary embolus

An embolus that travels to the lungs is called a...

Deep vein thrombosis

An embolus that travels to a vein in the leg is called...

Myocardial infarction, Unstable angina, Atrial fibrillation, Indwelling devices, Major orthopedic surgery

Anticoagulants are used to prevent clot formation in 5 main settings:

Bleeding, nausea and vomiting, abdominal cramps, thrombocytopenia

The main side effects of anticoagulants include...

Increases

The risk of bleeding _______ (increases or decreases) with an increased dose of anticoagulants

Thrombocytopenia

the condition that occurs when the platelet count in your blood is too low

Activated Partial Thromboplastin Time (aPTT)

A screening test that helps evaluate a person's ability to appropriately form blood clots is...

seconds

The aPTT is measured in ______

therapeutic

The aPTT helps to keep medication in the ___________ range

Heparin

Which anticoagulant drug is monitored daily by aPTT?

Heparin

Which anticoagulant drug is given parenterally?

1 to 2

Heparin has a short half life of ____ to ____ hours

Protamine sulfate

The effects of heparin can be reversed by...

True

T/F SC doses of heparin should be given in areas of deep subcutaneous fat and sites should be rotated

the umbilicus, abdominal incisions, unhealed wounds

Subcutaneous doses of drugs should not be given within two inches of...

hematoma

SC injections should not be aspirated as it can cause the formation of a...

False

T/F SC injection sites should be massaged after the injection

bolus, IV infusion

IV doses of heparin may be given by ______ or ___________

Immediately

Anticoagulant effects of heparin are seen ___________ (immediately, 30 minutes later, 1 hour later)

Low-molecular-weight heparin

Enoxaparin and dalteparin are examples of what kind of anticoagulant drug?

more

Low-molecular-weight heparins have a _____ (more or less) predictable anticoagulant response

false

T/F low-molecular-weight heparins require constant aPTT monitoring

abdomen

low-molecular-weight heparins are given subcutaneously in the __________, rotating injections sites

International Normalization Ratio (INR)

the standard unit for reporting the clotting time of blood is

2.0 to 3.0

A standard INR for a client taking anticoagulants is ____ to _____

Warfarin sodium

Which anticoagulant drug is given orally?

INR

Warfarin sodium is monitored regularly by _____

vitamin k

What substance can be given if warfarin sodium toxicity occurs?

IM, IV, PO

Vitamin K can be given by which routes?

true

T/F Warfarin sodium may be started while the client is still on heparin until prothrombin times indicate adequate anticoagulation

Several days after

The therapeutic effect of warfarin sodium occurs __________ (immediately, 30 minutes after, one hour after, several days after)

Antiplatelet drugs

aspirin, dipyridamole (Aggrenox), Pentoxifylline (Trental), Clopidogrel (Plavix), and Ticlopidine (Ticlid) are all examples of what kind of drug?

Reduce

Antiplatelet agents ______ (increase or reduce) the risk of fatal and nonfatal strokes

False, they vary according to the agent

T/F the side effects for every antiplatelet drug is the same

overbleeding

The number one concern that nurses look for in a patient taking antiplatelet drugs is...

Nicotine

_________ causes vasoconstriction, which alters the effectiveness of antiplatelet agents

Older

streptokinase and urokinase are examples of ______ (older or newer) thrombolytic agents

Newer

Tissue plasminogen activator and Anisoylated plasminogen-streptokinase activator complex (APSAC) are examples of ________ (older or newer) thrombolytic agents

alteplase TPA, reteplase, tenecteplase

3 more examples of thrombolytic agents are...

fibrinolytic system

The system that breaks down blood clots is called the...

fibrinolytic

Step one of the mechanism of action of thrombolytic agents involves activating the ____________ system to break down the clot in the blood vessel quickly

plasminogen, plasmin

Step 2 of the mechanism of action of thrombolytic agents involves activating _________ to convert it to _________, which can digest fibrin and breaks down the thrombus

Coronary

The 3rd and final step in the mechanism of action of thrombolytic agents involves reestablishing blood flow to the heart muscle via the _________ arteries, preventing tissue destruction

Thrombolytic agents

Acute Myocardial Infarction, Arterial thrombolysis, Deep vein thrombosis, Occlusion of shunts or catheters, and a Pulmonary embolus are all indications for which drugs?

Bleeding, nausea and vomiting, hypotension, allergic reactions, dysrhythmias

The main side effects to watch for when using thrombolytic agents are...

Intracranial, internal, superificial

What are the 3 types of bleeding that can occur with the use of thrombolytic agents?

bleeding, redness, pain

What should be monitored in a client using thrombolytic agents intravenously?

Internal bleeding

Decreased BP, restlessness, and increased pulse are signs of...

Excessive/abnormal bleeding

Bleeding of gums while brushing teeth, unexplained nosebleeds, heavier menstrual bleeding, bloody or tarry stools, bloody urine or sputum, abdominal pain, vomiting blood are signs of...

Client education

Emphasizing the importance of regular lab testing, signs of abnormal bleeding, measures to prevent bruising, bleeding, or tissue injury, monitoring for signs of excessive bleeding, and wearing a medical alert bracelet, are all aspects of...

Vitamin K

tomatoes, dark leafy green vegetables, bananas, and fish are foods that are contraindicated in clients taking anticoagulants because they are high in what substance?