Ch. 14: Drugs Affecting the Hematologic System Flashcards
Platelet inhibitors
these drugs use a variety of mechanisms to prevent platelets from sticking together (aggregating) to form a platelet plug that starts the blood clotting cascade
Platelet inhibitor drugs
aspirin (Ecotrin), cilostazol (Pletal), clopidogrel (Plavix), ticagrelor (Brilinta), ticlopidine (Ticlid)
Direct thrombin inhibitors
these drugs bind to prothrombin and prevent its conversion to thrombin, which is needed to convert fibringoen to fibrin. With less thrombin, less fibrin is available to form the network that is the mesh forming the base of a clot
Direct thrombin inhibitor drugs
apixaban (Eliquis), desirudin (Iprivask), dabigatran (Pradaxa), rivaroxaban (Xarelto)
Indirect thrombin inhibitors
these drugs indirectly prevent the conversion of prothrombin to thrombin by increasing the amount of active antithrombin III. This substance has the action of interfering with the conversion of prothrombin to thrombin
Indirect thrombin inhibitor drugs
heparin, heparin sodium (Calcilean, Hepealean), enoxaparin (Lovenox), dalteparin (Fragmin), tinzaparin (Innohep), fondaparinux sodium (Arixtra)
Nursing implications of platelet inhibitors
avoid taking OTC drugs, especially those that contain NSAIDs, antacids interfere with antiplatelet drugs, most oral antiplatelet drugs are better tolerated when given with food to prevent nausea, teach patients the symptoms of bleeding and to report any signs of abnormal bleeding to the healthcare provider, teach patients to avoid the foods, herbs, and supplements that can interfere with antiplatelet drugs, teach patients not to stop taking these drugs without talking to their provider. Drugs may need to be held for certain surgical or dental procedures. Antiplatelet drugs should be avoided during the last trimester of pregnancy and should not be taken while breast-feeding
Direct thrombin inhibitor drugs
watch for signs of abnormal bleeding and teach patients to report abnormal bleeding, including heavy menses; monitor patients for signs of allergy or hypersensitivity to these drugs. Teach patients to avoid aspirin or NSAIDs while taking thrombin inhibitors because serious hemorrhage or death could occur. Keep the drugs in the original containers; do not place in plastic pill containers
Indirect thrombin inhibitor nursing implications
watch for signs of abnormal bleeding and teach patients to report abnormal bleeding, including heavy menses. Monitor patients who are receiving heparin for indications of allergy or hypersensitivity. Teach patients to avoid aspirin or NSAIDs while taking heparin preparations. Assess patients who are receiving heparin for low platelet counts and indications of clot extension
Vitamin K antagonist drugs
warfarin (Coumadin)
Vitamin K nursing implications
teach patients to limit the amount of green, leafy vegetables they eat because these vegetables are a natural source of vitamin K. Monitor patient’s INR to determine effectiveness. Remind patients to keep all appointments for INR. Stress the importance of not taking aspirin or NSAIDs with this drug. Teach patients the signs of abnormal bleeding to report to the healthcare provider. Caution women of childbearing age who are taking warfarin to avoid pregnancy
Platelet inhibitor drugs work in
a patient who might be having reduced blood circulation to the heart before a myocardial infarction
-given prophylactically to reduce blood clots
Platelet inhibitors may be given in adjunct to
thrombolytic therapy, to prevent heart attack
Acetylsalicylic acid (ASA)
or aspirin, is the most commonly used antiplatelet drug
-reduces the risk for major blood vessel blockage
Aspirin is used in
acute myocardial infarction (MI), ischemic stroke, angina, and peripheral arterial disease
Complications of ASA use
GI bleeding in older patients, those with a history of peptic ulcer disease, and patients using other NSAIDs
Clopidogrel (Plavix)
a drug that is used for patients who have had an MI caused by a clot (thrombus) formed in a coronary artery
Clopidogrel must be taken
daily for a year or longer to prevent clots from developing and plugging up the stent
Side effects of platelet inhibitors
bleeding, easy bruising, bleeding of the gums, diarrhea, nausea, dyspepsia, vomiting, flatulence, and anorexia
skin rashes, pruritis, and purpura
Adverse reactions of platelet inhibitors
excessive bleeding, itching, hives, and runny nose; with more severe reactions include swelling of the lips, tongue, or face or acute cardiovascular events
Thrombocytopenia
decrease in platelet counts
Neutropenia
white blood cell counts
Drug and food interactions of platelet inhibitors
other drugs that reduce coagulation, alcohol, vitamin K, oral contraceptives, antibiotics proton pump inhibitors
green leafy vegetables, St John’s wort
Direct thrombin inhibitors action
interferes with factor II, which increases the time it takes for blood to clot; binds to free thrombin in the blood and thrombin that is bound to fibrin
DTIs uses
are also used to prevent clots in arteries and veins, such as DVT, PE, clotting from A-fib, abnormal heart rhythm
-used like warfarin and anticoagulants
Side effects of DTIs
can cause bleeding, easy bruising, bleeding gums, gastric upset (taken on empty stomach)
Adverse reactions of DTIs
excessive bleeding and thrombocytopenia
Early signs of DTI overdose
bleeding from the gums while brushing teeth, excessive bleeding or oozing from cuts, unexplained bruising or nosebleeds, and unusually heavy menses in women
Drug interactions with DTIs
atorvastatin, azithromycin, carvedilol, clarithromycin, cyclosproine, diltiazem, and St. John’s wort
Drugs that decrease the effects of DTIs
carbamazepine, dexamethasone, phenobarbital, phenytoin, or rifampin; antacids may as well
DTI antidote
idarucizumab
Instruct patients to keep DTIs in original bottle
to protect drug from moisture and light
Instruct patients to take DTIs with a
full glass of water to prevent stomach irritation and improve absorption
Indirect thrombin inhibitor actions
inhibits thrombin from clotting
Low-molecular-weight heparin (LMWH)
more steady anticoagulation effect than heparin, binds to antithrombin and inhibiting factor Xa
The half-life of LMWH is longer than
heparin sodium
LMWH uses
anticoagulation therapy with heparin is used to prevent new clot formation or to stop existing clots from growing in size
Heparin is used
prophylactically, during and after surgeries, patients with heart valve disease, patients with dysrhythmias and in patients receiving hemodialysis
Used in the prevention of venous thromboembolism and may be used when PE is present
LMWH
Expected side effects of heparin sodium
easy bleeding, and bruising, pain, redness, warmth, irritation, or skin changes where the drug was injected. Other side effects may include foot itching or bluish-colored skin
Adverse reactions of heparin sodium
hemorrhage, thrombocytopenia, shortness of breath, wheezing, chills, fever, alopecia, and hypersensitivity reaction
In the event of heparin overdose
protamine sulfate is given to counteract the effect of heparin
Heparin-induced thrombocytopenia (HIT) and heparin-induced thrombocytopenia and thrombosis (HITT)
In HIT, antibodies against heparin are formed and activate platelets, which clump together and cause small clots in the bloodstream, and the platelet count falls; if major clots develop and block vessels, the condition is even more serious and is called HITT
Drug interactions of heparin sodium
aspirin, NSAIDs, glucocorticoids, and other anticoagulants (warfarin) to increase the risk for GI bleeding. Antihistamines, digoxin, nicotine, and tetracycline decrease the anticoagulant effect of heparin
For injection of heparin
use a small (25-gauge) needle and a tuberculin syringe for the subcutaneous injection (given every 12 hours)
Continuous IV therapy with heparin is first started by a bolus of heparin that is based on the weight of the patient
usually 5,000 to 10,000 units
Vitamin K antagonists actions
inhibit the enzyme needed for final activation of the vitamin K
Vitamin K antagonists uses
for long-term therapy in chronic conditions that might involve problems with clot formation
Vitamin K antagonists expected side effects
potential for easy bruising and bleeding is common
Warfarin may produce
GI upset, headache, and skin rash
Vitamin K antagonist adverse reactions
excessive bleeding, or hemorrhage that can be seen with very heavy menstrual bleeding, frank blood or dark, tarry stools, or coffee-colored vomitus with excessive dosage
Warfarin can cause
skin necrosis, and birth defects or death to the fetus
Vitamin K can be given
orally or parenterally to help stimulate the liver to resume manufacture of prothrombin and serve as an anticoagulant antagonist
Drug and Food interactions with vitamin k antagoinsts
many antibiotics, anti-inflammatory drugs, antidysrhythmics, GI drugs, statins, and steroids can lengthen bleeding time effects of warfarin, whereas antacids, antihistamines, barbiturates, large doses of vitamin C, and oral contraceptives can shorten it
Eating excessive amounts of green, leafy vegetables can
interfere with the purpose of vitamin K antagonist therapy, decrease bleeding time, and reduce effectiveness of the treatment, leading to new blood clot formation
Fibrinolytic drugs
formerly called thrombolytic drugs actually do dissolve and break down existing blood clots
Fibrinolytic drug actions
work by converting plasmingoen to the enzyme plasmin, which breaks down fibrin clots, fibringoen, and other plasma proteins. These products are used only in a critical care setting
Fibrinolytic uses
used in the acute care setting such as the emergency department or intensive care unit. Acute MI, acute pulmonary emboli, acute ischemic stroke, and acute arterial occlusion. These drugs dissolve clots and emboli, reducing the cellular damage from arterial blockage
Most commonly used fibrinolytic drugs are
alterplase (Activase), tPA, reteplase (Retavase), and tenecteplase (TNKase)
Fibrinolytic drug nursing implications
before therapy, ensure the patient has no history of active bleeding disorders, certain surgeries, blood pressure is lower than 200/120, pregnancy or delivery, head trauma prolonged cardiopulmonary resuscitation, or pending aortic dissection (contraindications)
watch for signs of hemorrhage
monitor patients who are taking heparin for wheezing, shortness of breath chest tightness facial swelling, and rash or hives (allergic reaction)
monitor coagulation laboratory tests
monitor for the presence of severe headache or changes in alertness (stroke)
avoid giving IM drugs because of the risk for bleeding
Expected side effects of fibrinolytics
bleeding or low blood pressure
Adverse reaction of fibrinolytics
allergic reactions and hypersensitivity, hemorrhage is the most critical adverse reaction that can occur
risk for stroke
contraindications include known bleeding disorders, pregnancy or recent delivery, history of stroke within the past 2 months, hypertension with a blood pressure above 200/120, head trauma, and aortic dissection
Drug interactions of fibrinolytics
with other anticoagulants increase the potential for bleeding and hemorrhage
Erythropoiesis-stimulating agents
synthetic forms of the hormone erythropoietin
ESAs action
oxygenate the body
ESAs uses
usually given to patients with a condition that causes anemia, and who need to increase the production of RBCs
Patients who are anemic from the effects of chemotherapy on the bone marrow or who may be anemic before surgery are often prescribed
ESAs
ESAs reduce the need for
blood transfusions and reduce the complications of transfusions, such as fluid overload
Expected side effects of ESAs
pain at the injection site, generalized body aches and pain, skin rash, redness or warmth at the injection site can occur
Adverse reactions of ESAs
hypertension, blood clots, stroke, and MI
in some advanced cancers, increased tumor growth occurred where ESAs were given
risk for severe allergic reaction
Nursing implications of ESAs
monitor blood pressure for increases due to increased blood viscosity, headache, body aches, fever or chills
monitor blood counts, to help determine drug effectiveness
follow directions for drug mixing and preparation because these vary by product
check for signs or symptoms of allergic reaction
teach patients to immediately report chest pain or shortness of breath, drooping face, or numbness in face or extremities
