Ch 7 Anticoagulants

Front 1

Fibrinolysin

Back 1

enzyme that breaks down the fibrin meshwork that stabilizes blood clots; also referred to as plasmin

Front 2

Hemostasis

Back 2

prevention or stoppage of blood loss from an injured blood vessel and is the process that maintains the integrity of the vascular compartment

Front 3

Heparin-induced thrombocytopenia (HIT)

Back 3

immune-mediated prothrombotic reaction resulting in a decrease in platelet count associated with heparin administration in patients with detectable HIT antibodies

Front 4

Plasmin

Back 4

enzyme that breaks down the fibrin meshwork that stabilizes blood clots; also referred to as fibrinolysin

Front 5

Plasminogen

Back 5

inactive protein found in many body tissues and fluids, is bound to fibrin and becomes a component of the clot.

Front 6

Prothrombotic reaction

Back 6

adverse effect that leads to thrombogenesis

Front 7

Thrombogenesis

Back 7

formation of a blood clot

Front 8

Thrombolysis

Back 8

breakdown or dissolution of blood clots

Front 9

Thrombolytics

Back 9

drugs that dissolve blood clots

Front 10

Thrombosis

Back 10

formation of a blood clot

Front 11

Thrombus

Back 11

blood clot

Front 12

Anticoagulant, antiplatelet, and thrombolytic drugs are used for:

Back 12

prevention and management of thrombotic and thromboembolic disorders

Front 13

Atherosclerosis

Back 13

the basic disease process that often leads to pathologic thrombosis;

begins with accumulation of lipid-filled macrophages (i.e., foam cells) on the inner lining of arteries

Front 14

Arterial blood clots in the cerebral, pulmonary, or cardiac system can produce a

Back 14

cerebrovascular accident, pulmonary embolism, or myocardial infarction,

Front 15

Venous blood clots may lead to

Back 15

DVT; classic symptoms include leg swelling and pain on palpation in the calf or thigh

Front 16

Anticoagulant drugs

Back 16

prevent formation of new clots and extension of already existing clots, do not dissolve clots that have already formed. Widely used in thrombotic disorders, they aremore effective in preventing venous thrombosis than arterial thrombosis.

Front 17

Antiplatelet drugs

Back 17

drugs used to prevent arterial thrombosis

Front 18

Thrombolytic drugs

Back 18

used to dissolve thrombi and limit tissue damage in selected thromboembolic disorders.

Front 19

three types of anticoagulants

Back 19

heparins, vitamin K antagonists, and direct thrombin inhibitors (DTIs).

Front 20

Heparin

Back 20

pharmaceutical preparation of the natural anticoagulant produced primarily by mast cells in pericapillary connective tissue, and it is the prototype anticoagulant.

Front 21

Endogenous heparin

Back 21

found in various body tissues, most abundantly in the liver and lungs.

Front 22

Exogenous heparin

Back 22

obtained frombovine lung or porcine intestinal mucosa and standardized in units of biologic activity.

Front 23

Heparin prototype

Back 23

Heparin

Front 24

Vitamin K antagonists prototype

Back 24

warfarin

Front 25

Direct thrombin inhibitors prototype

Back 25

lepirudin

Front 26

Heparins other drugs in class

Back 26

Dalteparin

Enoxaparin

Fondaparinux*

Front 27

Vitamin K antagonists drugs in class

Back 27

none?

Front 28

Direct thrombin inhibitors other drugs in class

Back 28

Argatroban

Bivalirudin

Dabigatran etexilate

Desirudin

Rivaroxaban

Front 29

Antiplatelet Drugs class

Back 29

Adenosine diphosphate receptor antagonists

Front 30

Adenosine diphosphate receptor antagonists prototype

Back 30

clopidogrel

Front 31

Adenosine diphosphate receptor antagonists other drugs

Back 31

Prasugrel

Ticlopidine

Tirofiban

Front 32

Other antiplatelet drugs

Back 32

Abciximab

Anagrelide

Aspirin

Cilostazol

Dipyridamole

Eptifibatide

Front 33

Thrombolytic Drugs prototype

Back 33

Alteplase

Front 34

Thrombolytic other drugs in class

Back 34

Drotrecogin alfa, activated

Reteplase, recombinant

Streptokinase

Tenecteplase

Front 35

Drugs Used to Control Bleeding

Back 35

Aminocaproic acid

Protamine sulfate

Tranexamic acid

Vitamin K

Front 36

Heparin administration route

Back 36

IV or SubQ only

Rationale: GI tract does not absorb this drug

Front 37

Heparin pharmacokinetics

Back 37

After intravenous (IV) injection, it acts immediately. After subcutaneous injection, it acts within 20 to 30 minutes. Metabolism takes place in the liver and the reticuloendothelial system. Excretion, primarily in the form of inactive metabolites, occurs in the urine. Hemodialysis does not remove it.

Front 38

Heparin prophylactical use

Back 38

to prevent DVT and pulmonary embolism

Front 39

patients at risk for certain disorders take low doses of heparin prophylactically because of these disorders

Back 39

Major illnesses (e.g., acute myocardial infarction, heart failure, serious pulmonary infections, stroke)

Major abdominal or thoracic surgery

A history of thrombophlebitis or pulmonary embolism, including pregnant women

Gynecologic surgery, especially in patients who have been taking estrogens or oral contraceptives or have other risk factors for DVT

Restrictions such as bed rest or limited activity expected to last longer than 5 days

Front 40

Heparin therapeutic use

Back 40

a. for management of acute thromboembolic disorders (e.g., DVT, thrombophlebitis, pulmonary embolism).

b. to prevent further thrombus formation and embolization.

c. use in disseminated intravascular coagulation (DIC),

Front 41

disseminated intravascular coagulation (DIC),

Back 41

a life-threatening condition characterized by widespread clotting, whichdepletes the blood of coagulation factors. The depletion of coagulation factors then produces widespread bleeding.

Front 42

Goal of heparin therapy in DIC

Back 42

prevent blood coagulation long enough for clotting factors to be replenished and thus be able to control hemorrhage.

Front 43

in addition, clinicians use heparin to:

Back 43

prevent clotting during cardiac and vascular surgery, extracorporeal circulation, hemodialysis, and blood transfusions, and in blood samples to be used in laboratory tests.

Front 44

True or false:

Heparin does not cross the placental barrier and is not secreted in breast milk

Back 44

True, making it the anticoagulant of choice for use during pregnancy and lactation.

Front 45

Heparin contraindications

Back 45

GI ulcerations (e.g., pepticulcer disease, ulcerative colitis), intracranial bleeding, dissecting aortic aneurysm, blood dyscrasias, severe kidney or liver disease, severe hypertension, polycythemia vera, and recent surgery of the eye, spinal cord, or brain.

Front 46

Drugs That Increase the Effects of Heparin

Back 46

AlteplaseIncreases the risk of bleeding

AntithrombinIncreases pharmacologic effects

CephalosporinsLead to potential coagulopathies and risk of bleeding

Direct thrombin inhibitorsIncrease the risk of bleeding

Drotrecogin alfaIncreases the risk of bleeding

Penicillins (parenteral)Lead to altered platelet aggregation and increased risk of bleeding.

Platelet inhibitorsIncrease the risk of bleeding

WarfarinMay prolong and possibly invalidate the PT; if receiving both heparin and warfarin, draw blood for the PT at least 5 hours after the last IV heparin dose

Front 47

Drugs That Decrease the Effects of Heparin

Back 47

AntihistaminesDecrease the anticoagulant effect

DigoxinDecreases the anticoagulant effect

NicotineDecreases the anticoagulant effect

Nitroglycerin (IV)Decreases the anticoagulant effect

StreptokinaseLeads to relative resistance to anticoagulation

TetracyclineDecreases the anticoagulant effect

Front 48

Herbs and Foods That Increase the Effects of Heparin

Back 48

Chamomile, garlic, ginger, ginkgo, ginseng, high-dose vitamin E

Front 49

True or False

No herbs or foods that decrease the effects of heparin have been identified.

Back 49

True, some herbs increase effects not decrease

Front 50

activated partial thromboplastin time (aPTT)

Back 50

sensitive to changes in blood clotting factors, except factor VII, to regulate heparin dosage. Normal or control values of indicate normal blood coagulation, and therapeutic values of adequate anticoagulation indicate low levels of clotting factors and delayed blood coagulation

Front 51

during heparin therapy, aPTT should be at

Back 51

1.5 to 2.5 times the control or baseline value

Front 52

aPTT normal control value

Back 52

25 to 35 seconds

Front 53

aPTT therapeutic values of adequate anticoagulation

Back 53

45 to 70 seconds, approximately.

Front 54

intermittent administration; 1 hour; thromboembolism;LMWHs

Back 54

aPTT may be drawn at any time; with ___________, blood for the aPTT should be drawn approximately ______ before a dose of heparin is scheduled. It is not necessary to monitor aPTT with low-dose standard heparin given subcutaneously forprophylaxis of __________ or with the _____ (e.g., enoxaparin).

Front 55

Disadvantages of heparin

Back 55

a.parenteral injection is necessary,

b.the drug has a short duration of action, which means that there is a need for frequent administration.

Front 56

Assessing for therapeutic effect of heparin

Back 56

assesses for the absence or reduction of signs and symptoms of thrombotic disorders (e.g., less edema and pain with DVT, less chest pain and respiratory difficulty with pulmonary embolism, absence of uncontrolled bleeding). It is also necessary to ensure that aPTT values are within the therapeutic range.

Front 57

Assessing for adverse effects

Back 57

assesses the patient for signs of overt bleeding or HIT

Front 58

Heparin antidote

Back 58

Protamine sulfate

Front 59

Warfarin (Coumadin)

Back 59

most commonly used oral anticoagulant and is the prototype vitamin K antagonist

Front 60

Warfarin pharmacokinetics

Back 60

well absorbed after oral administration. Administration with food may delay the rate but not the extent of absorption. The drug is highly bound to plasma proteins (98%), mainly albumin. Metabolism takes place in the liver. Excretion, primarily as inactive metabolites, occurs in the kidneys. Renal impairment does not affect drug metabolism but may decrease excretion of the drug.

Front 61

foods high in vit. K (decreases effect of warfarin)

Back 61

broccoli, brussels sprouts, cabbage, cauliflower, chives, collard greens, kale, lettuce, mustard greens, peppers, spinach, tomatoes, turnips, and watercress.

Front 62

Enoxaparin teaching

Back 62

you need an injection usually every 12 hours. You or someone close to you may be instructed in injecting the medication, or a visiting nurse may do the injections, if necessary.

Front 63

Warfarin teaching

Back 63

you need to avoid walking barefoot; avoid contact sports; use an electric razor; avoid injections when possible; and carry an identification card, necklace, or bracelet (e.g., MedicAlert) stating the name of the drug and the health care provider’s name and telephone number.

Front 64

Enoxaparin self-administration teaching

Back 64

wash hands and cleanse skin to prevent infection; inject deep under the skin, around the navel, upper thigh, or buttocks; and change the injection site daily. If excessive bruising occurs at the injection site, rubbing an ice cube over an area before the injection may be helpful.

Front 65

Warfarin self-administration teaching

Back 65

as with all medications, take as prescribed. Because the prescriber may set a dosing schedule that could vary from 1 day to the next, do not rely on memory but keep a written record of the date and the amount of medication taken.

Front 66

Warfarin; warfarin; Vit.K; warfarin; Warfarin; 3 to 5 days; warfarin

Back 66

_________ acts in the liver to prevent synthesis of vitamin K–dependent clotting factors (i.e., factors II, VII, IX, and X). Similar to vitamin K in structure, ________ therefore acts as a competitive antagonist to hepatic use of vitamin K. Conversely, _________ serves as the antidote for ________. ________ has no effect on circulating clotting factors or on platelet function, so the anticoagulant effects do not occur for ______ days after ________ is started because clotting factors already in the blood follow their normal pathway of elimination.

Front 67

Warfarin

Back 67

_________ is most useful in long-term prevention or management of venous thromboembolic disorders, including DVT, pulmonary embolism, and embolization associated with atrial fibrillation and prosthetic heart valves.

Front 68

Warfarin

Back 68

_________ therapy after myocardial infarction may decrease reinfarction, stroke, venous thromboembolism, and death

Front 69

Which body organ eliminates warfarin?

Back 69

Liver

Front 70

The primary adverse effect: warfarin

other side effects

Back 70

associated with _____therapy is hemorrhage. Additionally, nausea, vomiting, abdominal pain, alopecia, urticaria, dizziness, and joint or muscle pain may occur.

Front 71

T or F

Warfarin, a pregnancy category X medication, is contraindicated during pregnancy because it crosses the placenta and may produce fatal fetal hemorrhage.

Back 71

True. Warfarin in pregnancy category X. Black box warning!

Front 72

Drugs That Increase the Effects of Warfarin

Back 72

acetaminophen (high dose), allopurinol, amiodarone

b. Alteplase, androgens, aspirin and other nonsteroidal anti-inflammatory drugs, azithromycin, bismuth subsalicylate, carbamazepine, chloral hydrate, chloramphenicol, cimetidine, ciprofloxacin and other quinolone antibiotics, cisapride, clarithromycin, clofibrate, cotrimoxazole, direct thrombin inhibitors, drotrecogin alfa, heparin, macrolide antibiotics, omeprazole, pravastatin, propranolol, quinidine, ranitidine, ritonavir, sertraline, simvastatin, streptokinase, sulfinpyrazone, sulfonamide, tamoxifen, tetracyclines, thyroid hormones, tricyclic antidepressants, vancomycin , vitamin E

c. Antithrombin

d. Cephalosporins

Front 73

Drugs That Decrease the Effects of Warfarin

Back 73

a. Chlordiazepoxide, haloperidol, intravenous lipid emulsions (contains soybean oil), isotretinoin, meprobamate, spironolactone

b. Chlorthalidone

c. Ethchlorvynol, trazodone

d. Etretinate

Front 74

Herbs and Foods That Increase the Effects of Warfarin

Back 74

Angelica

Cat’s claw

Chamomile

Chondroitin

Cranberry juice

Feverfew

Garlic

Ginkgo

Goldenseal

Grape seed extract

Green tea

Psyllium

Turmeric

Front 75

Herbs and Foods That Decrease the Effects of Warfarin

Back 75

Ginseng

St. John’s wort

Vitamin K Foods high in vitamin K (broccoli, brussels sprouts, cabbage, cauliflower, chives, collard greens, kale, lettuce, mustard greens, peppers, spinach, tomatoes, turnips, and watercress)

Front 76

QSEN Safety Alert: Warfarin

Back 76

When warfarin therapy begins, daily evaluation of INR is necessary until a stable daily dose is reached (the dose that maintains the prothrombin time [PT] and INR within therapeutic ranges and does not cause bleeding). A therapeutic PT value is approximately 1.5 times control, or 18 seconds. Thereafter, a patient’s INR values require checking every 2 to 4 weeks for the duration of oral anticoagulant drug therapy. If a prescriber changes the warfarin dose, more frequent INR measurements are necessary until a stable daily dose is again established.

Front 77

INR value above 3.0

Back 77

Institutions often have protocol for the therapeutic range of INR. In the absence of a protocol, the nurse holds the dose if the INR is _________ and notifies the health care provider.

Front 78

Assessing for Therapeutic Effects: Warfarin

Back 78

nurse assesses for the absence or reduction of signs and symptoms of thrombotic disorders (e.g., less edema and pain with DVT, less chest pain and respiratory difficulty with pulmonary embolism, absence of uncontrolled bleeding, hematuria or blood in the stools). It is also necessary to ensure that PT and INR values are within the therapeutic range.

Front 79

Assessing for Adverse Effects

Back 79

nurse assesses for signs of bleeding, including excessive bruising of the skin, bleeding from IV sites or the gum line, and blood in urine or stool.

Front 80

INR and PT therapeutic values

Back 80

INR: 2.0 and 3.0

PT: 1.5 times control or 18 seconds

Normal baseline or control PT is ~12 seconds

Front 81

DTIs benefits/ advantages

Back 81

a. inhibition of both circulating and clot-bound thrombin

b. more predictable dose–response anticoagulant effect

c. inhibition of thrombin-induced platelet aggregation

d. lack of production of immune-mediated thrombocytopenia

Front 82

indirect inhobitors of thrombin

Back 82

Heparin and warfarin

Front 83

Lepirudin Pharmacokinetics (DTI)

Back 83

__________, which cannot be absorbed by the GI tract, is administered intravenously and is distributed to the extracellular fluids. The metabolic pathway has not been established. The drug is excreted in the urine, and the systemic elimination is proportional to the glomerular filtration rate. Typically, the elimination half-life is 60 minutes.

Front 84

Lepirudin Action

Back 84

__________ is a highly specific direct inhibitor of thrombin, but unlike heparin, its mechanism of action is independent of antithrombin III. DTIs have no known antagonists. Given intravenously, the drug has an onset within 30 to 90 minutes and has a duration of action for up to 24 hours. Safety and efficacy in children have not been established.

Front 85

Lepirudin use

Back 85

__________ is available for HIT, acute coronary syndrome, prophylaxis and treatment of venous thromboembolism, and management of atrial fibrillation. This drug and the other DTIs are less suitable for long-term treatment because administration by injection is necessary, therapeutic drug monitoring is not widely available, and no pharmacologic antidote to reverse the effects is available.

Front 86

Argatroban

Back 86

second agent, after lepirudin, to be indicated for HIT. But unlike lepirudin, __________ is eliminated in the liver and can be used in people with end-stage renal disease. Administered intravenously, argatroban is very short acting due to its reversible binding to thrombin and differs from lepirudin, which irreversibly binds to thrombin.

Front 87

Antiplatelet drugs

Back 87

prevent one or more steps in the prothrombotic activity of platelets

Front 88

arterial thrombi

Back 88

composed primarily of platelets, may form on top of atherosclerotic plaque and block blood flow in the artery. They may also form on heart walls and valves and embolize to other parts of the body.

Front 89

prototype ADP receptor antagonist

Back 89

clopidogrel (Plavix)

Front 90

Clopidogrel shortcomings

Back 90

delayed onset of action,

irreversible inhibitory effects on platelets with no reversing agent or antidote, and

significant individual variability in platelet response.

Front 91

Clopidogrel pharmacokinetics

Back 91

rapidly absorbed after oral administration and undergoes extensive first-pass metabolism in the liver. Platelet inhibition may occur 2 hours after a single dose, but the onset of action is slow, so that an initial loading dose is usually administered. The drug has a half-life of about 8 hours. The drug is excreted in the urine and feces.

Front 92

Clopidogrel Action

Back 92

irreversibly block the ADP receptor on platelet cell membranes. Effective dose-dependent prevention of platelet aggregation can be seen within 2 hours of a single oral dose, but the onset of action is slow, so that a loading dose of 300 to 600 mg is usually administered. Platelet inhibition essentially lasts for the lifespan of the platelet. With repeated doses of 75 mg/d, maximum inhibition of platelet aggregation is achieved within 3 to 7 days. Platelet aggregation progressively returns to baseline about 5 days after discontinuing the drug.

Front 93

Clopidogrel Use

Back 93

reduction of myocardial infarction, stroke, and vascular death in patients with atherosclerosis and in those after placement of coronary stents. Specific uses include prevention of vascular ischemic events in patients with symptomatic atherosclerosis or with acute coronary syndrome (with or without ST-segment elevation). In addition, after placement of an intracoronary stent for the prevention of thrombosis, patients may take this drug in conjunction with aspirin (dual antiplatelet therapy).

Front 94

Clopidogrel

Back 94

People with atrial fibrillation who are unable to take vitamin K antagonists take ___________ instead

Front 95

Clopidogrel

Back 95

Adding ___________ to aspirin in people with atrial fibrillation reduces the rate of major vascular events compared with aspirin alone but is associated with a greater risk of bleeding.

Front 96

Clopidogrel

Back 96

alternative antiplatelet drug for patients who cannot tolerate aspirin.

Front 97

Liver

Back 97

Because clopidogrel is metabolized in the _____, it may accumulate in people with hepatic impairment. Caution is necessary.

Front 98

Clopidogrel adverse effects

Back 98

The most common adverse effects associated with this drug are pruritus, rash, purpura, and diarrhea. Thrombotic thrombocytopenic purpura, hemorrhage, and severe neutropenia have also occurred.

Front 99

Clopidogrel contraindications

Back 99

Contraindications to this drug include hypersensitivity to the drug or any other component. It should not be used in patients with active bleeding in conditions such as intracranial hemorrhage or peptic ulcer disease. A category B medication, the drug requires cautious use in pregnant and lactating women.

Front 100

Clopidogrel: Nursing Implications

Back 100

The FDA has issued a BLACK BOX WARNING ♦ concerning the use of this drug in the 2% to 14% of the US population who are reduced metabolizers of the drug. As a result of genetic variations in CYP2C19 function, the drug may be less effective in altering platelet activity in these people. These “poor metabolizers” may remain at risk for heart attack, stroke, and cardiovascular death, and alternate dosing of the ___________ or the use of other antiplatelet drugs should be considered. Tests are available to determine if a patient is a poor metabolizer.

Front 101

Clopidogrel route and dosage

Back 101

PO 75 mg once daily with or without food

Front 102

Aspirin pregnancy category

Back 102

D (if full dose aspirin is taken in the third trimester)

Front 103

Aspirin Use

Back 103

Prevention of myocardial infarction

Front 104

Aspirin route and dosage

Back 104

PO 81–325 mg daily

Prevention of thromboembolic disorders in patients with prosthetic heart valves or TIAs

Front 105

Eptifibatide (Integrilin) pregnancy category

Back 105

B - requires cautious use in pregnant and lactating women

Front 106

Eptifibatide (Integrilin) Use

Back 106

Acute coronary syndromes, including patients who are to be managed medically and those undergoing PTCA

Front 107

Eptifibatide (Integrilin) Route and Dosage

Back 107

IV bolus injection, 180 mcg/kg, followed by continuous infusion of 2 mcg/kg/min. See manufacturer’s instructions for preparation and administration.

Front 108

Drugs That Increase the Effects of Clopidogrel

Back 108

AspirinIncreases the risk of bleeding

AtorvastatinMay affect antiplatelet activity

Barbiturates, carbamazepine, rifampin, rifapentineEnhances antiplatelet effect

Nonsteroidal anti-inflammatory drugsIncrease the risk of bleeding

Platelet inhibitorsIncrease the risk of bleeding

RifabutinMay increase metabolism of clopidogrel

ThrombolyticsIncreases the risk of bleeding

Front 109

Drugs That Decrease the Effects of Clopidogrel

Back 109

Amiodarone, dalfopristin, delavirdine, diltiazem, quinupristin, Vaprisol, zafirlukastAffect cytochrome 450 3A4 enzymes, which play a role in clopidogrel metabolism

Clarithromycin, erythromycin, ketoconazole, verapamilReduce antiplatelet activity

OmeprazoleMay lead to inadequate platelet response

Selective serotonin reuptake inhibitorsMay increase the risk of bleeding

Front 110

Herbs and Foods That Increase the Effects of Clopidogrel

Back 110

Garlic

Ginkgo biloba

Ginger

Green tea

Horse chestnut

Front 111

Assessing for Therapeutic Effects: Clopidogrel

Back 111

assesses for the absence of vascular ischemic events (e.g., pain, cyanosis, coolness of extremities). In addition, he or she ensures that hemoglobin and hematocrit levels are within normal limits.

Front 112

Assessing for Adverse Effects: Clopidogrel

Back 112

assesses for common adverse effects, including pruritus, rash, purpura, and diarrhea; thrombotic thrombocytopenic purpura and hemorrhage; and severe neutropenia.

Front 113

Antiplatelet drugs teaching consideration use

Back 113

are given to people who have had, or who are at risk of having, a heart attack, stroke, or other problems from blood clots. For prevention of a heart attack or stroke, you are most likely to be given ______ (e.g., aspirin, clopidogrel).

Front 114

5 to 7 days

Back 114

Antiplatelet drugs should be withheld ______ days prior to a planned surgical procedure.

Front 115

Aspirin (self-administration)

Back 115

Take _______ with food or after meals, with 8 ounces of water, to decrease stomach irritation. However, stomach upset is uncommon with the small doses used for antiplatelet effects. Do not crush or chew coated tablets (long-acting preparations).

Front 116

Main use of thrombolytic agents

Back 116

management of acute, severe thromboembolic disease, such as myocardial infarction, pulmonary embolism, and iliofemoral thrombosis.

Front 117

Goal of thrombolytic therapy

Back 117

reestablish blood flow as quickly as possible and prevent or limit tissue damage. In coronary circulation, restoration of blood flow reduces morbidity and mortality by limiting myocardial infarction size. In cerebral circulation, rapid thrombus dissolution minimizes neuronal death and brain infarction that produce irreversible brain injury.

Front 118

Decrease reformation of thrombus

Back 118

Anticoagulant drugs, such as heparin and warfarin, and antiplatelet agents are given following thrombolytic therapy to _________.

Front 119

prototype recombinant tissue plasminogen activator (rtPA)

Back 119

Alteplase (Activase)

Front 120

Alteplase pharmacokinetics

Back 120

Administration of this drug is by IV infusion. Metabolism occurs predominately in the liver. Following discontinuation of the infusion, more than 50% of the drug is cleared, with more than 80% clearance within 10 minutes. Excretion takes place in the urine. Whether this drug crosses the placenta or is excreted into breast milk is unknown.

Front 121

Alteplase Action

Back 121

__________ is a protein that lyses unwanted fibrin blood clots by catalyzing the conversion of plasminogen to plasmin.

Front 122

Alteplase Use

Back 122

Indications for alteplase include lysis of acute coronary arterial thromboembolism associated with evolving transmural myocardial infarction or acute pulmonary thromboembolism. Clinicians also considered it as first-line therapy for the treatment of acute ischemic stroke in selected people.

Front 123

Alteplase Adverse Effects

Back 123

bleeding (avoid invasive procedures)

omit anticoagulants and antiplatelet while using thrombolytics

symptomatic brain hemorrhage

3% mortality rate

6% - 8% risk of symptomatic hemorrhage

Front 124

rtPA antidote (Alteplase)

Back 124

Aminocaproic acid

Front 125

Alteplase contraindications

Back 125

Due to an increased risk of bleeding, this drug is contraindicated in patients with uncontrolled severe hypertension, aneurysm, arteriovenous malformation, known coagulopathy or internal bleeding, intracranial or intraspinal surgery or trauma within the past 3 months, intracranial mass, recent major surgery, or current use of oral anticoagulants. This drug can increase the risk of cerebral embolism in people with atrial fibrillation or atrial flutter.

Front 126

Alteplase pregnancy category

Back 126

C

Front 127

Alteplase route and dosage

Back 127

Ischemic stroke:IV infusion, 0.9 mg/kg total dose administered (not to exceed 90 mg), with 10% of the total dose administered as an initial IV loading dose over 1 min, and the remainder administered over 60 min.Myocardial infarction or PE:IV infusion, 100 mg over 3 h (first hour, 60 mg with a bolus of 6–10 mg over 1–2 min initially; second hour, 20 mg; third hour, 20 mg)Myocardial infarction: accelerated IV infusion, 100 mg total dosage administered as a 15 mg IV bolus, followed by 50 mg IV infused over 30 min, and then 35 mg IV infused over the next 60 min.IV infusion, 100 mg over 3 h (first hour, 60 mg with a bolus of 6–10 mg over 1–2 min initially; second hour, 20 mg; third hour, 20 mg)

Front 128

Alteplase Nursing Implication

Back 128

It is necessary to minimize intramuscular injections in patients who are receiving systemic thrombolytic therapy, because bleeding, bruising, or hematomas may develop.The nurse assesses patients for cardiac dysrhythmias, including sinus bradycardia, premature ventricular contractions, and ventricular tachycardia resulting from reperfusion following coronary thrombolysis. He or she must promptly identify and report any evidence of bleeding.

Front 129

Thrombolytic agent; alteplase

Back 129

Before a _____________ is begun, it is essential to check INR, aPTT, platelet count, and fibrinogen to establish baseline values and to determine whether a blood coagulation disorder is present. Two or three hours after __________ is started, the nurse ensures that the fibrinogen level is measured to determine that fibrinolysis is occurring. Alternatively, he or she can check INR or aPTT for increased values because the breakdown products of fibrin exert anticoagulant effects. During and following _________ administration, the nurse monitors blood pressure frequently and ensures that it is well controlled. The ISMP lists _________ as a high-alert drug because of its potential risk of causing significant harm when used in error.

Front 130

Drugs That Increase the Effects of Alteplase

Back 130

Aspirin or other salicylates, abciximab, cilostazol, clopidogrel, dalteparin, dipyridamole, enoxaparin, eptifibatide, fondaparinux, heparin, nonsteroidal anti-inflammatory drugs, tinzaparin, tirofiban, warfarinIncrease the risk of bleeding

Front 131

Alteplase route and consideration

Back 131

Administration is IV as a bolus injection or infusion. The nurse administers all infusions using an IV infusion device. It is necessary to reconstitute this drug as indicated and not to shake it.

Front 132

Herbs and Foods That Increase the Effects of Alteplase

Back 132

Cat’s claw

Dong quai

Evening primrose

Feverfew

Garlic

Ginkgo

Ginseng

Green tea

Horse chestnut

Red clover

Front 133

Alteplase assessing for adverse effects

Back 133

nurse assesses for evidence of bleeding. In addition, it is necessary to determine that the condition leading to initiation of this therapy is reversed and that there is a return of function. If bleeding does occur, it is most likely from a venipuncture or invasive procedure site, and local pressure may control it. If bleeding cannot be controlled or involves a vital organ, it is necessary to stop the drug and replace fibrinogen with whole blood plasma or cryoprecipitate. Giving aminocaproic acid or tranexamic acid may also be appropriate. When the drugs are used in acute myocardial infarction, cardiac dysrhythmias may occur when blood flow is reestablished. Therefore, antidysrhythmic drugs should be readily available.

Front 134

Aminocaproic acid (Amicar) Use

Back 134

Control bleeding caused by overdoses of thrombolytic agents or bleeding disorders caused by hyperfibrinolysis (e.g., cardiac surgery, blood disorders, hepatic cirrhosis, prostatectomy, neoplastic disorders); antidote for tPA

-IV, PO

Front 135

Protamine sulfate

Back 135

Treatment of heparin overdosage

Front 136

Vitamin K (Mephyton)

Back 136

Antidote for warfarin overdosage

PO 10 to 20 mg in a single dose

Front 137

Risk factors for thromboembolism include

Back 137

Immobility (e.g., limited activity or bed rest for more than 5 days

Obesity

Cigarette smoking

History of thrombophlebitis, DVT, or pulmonary emboli

Heart failure

Pedal edema

Lower limb trauma

Myocardial infarction

Atrial fibrillation

Mitral or aortic stenosis

Prosthetic heart valves

Abdominal, thoracic, pelvic, or major orthopedic surgery

Atherosclerotic heart disease or peripheral vascular disease

Use of oral contraceptives

Front 138

S&S DVT and thrombophlebitis

Back 138

usually occur in the legs. The conditions may be manifested by edema (the affected leg is often measurably larger than the other) and pain. Homans’ sign (pain in the calf when the foot is dorsiflexed) is generally unreliable as a clinical sign of DVT. If thrombophlebitis is superficial, it may be visible as a red, warm, tender area following the path of a vein.

Front 139

Pulmonary embolism S&S

Back 139

if severe enough to produce symptoms, is manifested by chest pain, cough, hemoptysis, tachypnea, and tachycardia. Massive emboli cause hypotension, shock, cyanosis, and death.

Front 140

Signs and symptoms DIC

Back 140

usually manifested by bleeding, which may range from petechiae or oozing from a venipuncture site to massive internal bleeding or bleeding from all body orifices.