Chapter 26 Coagulation Modifier Drugs

Question 1

Hemostasis is a general term for any process that stops bleeding. This can be accomplished by either mechanical or surgical means.
• When hemostasis occurs as a result of physiologic clotting of blood, it is called?

Answer 1

coagulation, which is the process of blood clot formation.

Question 2

The technical term for a blood clot is a?

When it is not stationary but moves through blood vessels it is called an?

Answer 2

thrombus.

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

Question 3

Normal hemostasis involves the complex interaction of substances that promote?
-and substances that either?

Answer 3

clot formation and substances that either inhibit coagulation or dissolve the formed clot.

Question 4

Substances that promote coagulation include?

Answer 4

platelets, von Willebrand factor, activated clotting factors, and tissue thromboplastin.

Question 5

Substances that inhibit coagulation include?

Answer 5

prostacyclin, antithrombin III, and proteins C and S. In addition, tissue plasminogen activator (t-PA) is a natural substance that dissolves clots that are already formed.

Question 6

The coagulation system is called a cascade (or coagulation cascade) because?

Answer 6

each activated clotting factor serves as a catalyst that amplifies the next reaction. The result is a large
concentration of a clot-forming substance called fibrin.

Question 7

Once a clot is formed and fibrin is present, what is activated?

Answer 7

fibrinolytic system is activated. This system initiates the breakdown of clots and serves to balance the clotting process.

Question 8

Hemophilia is a rare genetic disorder in which the previously mentioned natural coagulation and hemostasis factors are limited or absent. Hemophilia is categorized into two main types depending on?

Answer 8

which of the coagulation factors is absent (factor VII, factor VIII, and/or factor IX). Patients with hemophilia can bleed to death if coagulation factors are not given.

Question 9

Drugs that affect coagulation are commonly associated with adverse drug reactions.
• Coagulation modifiers work by?

Answer 9

preventing/promoting clot formation, lysing a preformed clot, and/or reversing the action of anticoagulants. Coagulation modifiers include anticoagulants, antiplatelets, thrombolytics, antifibrinolytics, and reversal drugs.

Question 10

Anticoagulants work by?

Answer 10

inhibit the action or formation of clotting factors and therefore prevent clots from forming.

Question 11

Antiplatelet drugs work by?

Answer 11

prevent platelet plugs from forming by inhibiting platelet aggregation, which can be beneficial in preventing heart attacks and strokes.

Question 12

Hemorheologic drugs alter?

Answer 12

platelet function without preventing the platelets from working.

Question 13

Sometimes clots form and totally block a blood vessel. When this happens in one of the coronary arteries, a?

Answer 13

heart attack occurs, and the clot must be lysed to prevent or minimize damage to the myocardial muscle.

Question 14

Thrombolytic drugs work by?

Answer 14

lyse (break down) clots, or thrombi, that have already formed.

Question 15

Antifibrinolytic drugs, also known as hemostatic drugs, have the opposite effect of these other classes of drugs; they actually promote?

Answer 15

blood coagulation and are helpful in the management
of conditions in which excessive bleeding would be
harmful.

Question 16

There are also several newer drug classes, including low– molecular-weight heparins (LMWHs), direct thrombin inhibitors, and selective factor Xa inhibitors.

Answer 16

.

Question 17

Drugs that prevent the formation of a clot by inhibiting
certain clotting factors are called anticoagulants.
• Once a clot forms on the wall of a blood vessel, it may dislodge
and travel through the bloodstream as an embolus. If
it lodges in a coronary artery, it causes a myocardial infarction
(MI); if it obstructs a brain vessel, it causes a stroke; if
it goes to the lungs, it is a pulmonary embolism; and if it
goes to a vein in the leg, it is a deep vein thrombosis (DVT).
Collectively, these complications are called thromboembolic
events.

Answer 17

.

Question 18

Anticoagulants are also called antithrombotic drugs because they work to?

Answer 18

prevent the formation of a clot or thrombus, a condition known as thrombosis. All anticoagulants work in the clotting cascade but do so at different points.

Question 19

Heparin works by?

Answer 19

binding to a substance called antithrombin III, which turns off three main activating factors:

(1) activated factor II (thrombin)
(2) activated factor X
(3) activated factor IX

Question 20

The drug name heparin usually refers to unfractionated
heparin, which is a relatively large molecule derived from
various animal sources. LMWHs are?

Answer 20

synthetic and have a smaller molecular structure; they include enoxaparin (Lovenox) and dalteparin (Fragmin).

Question 21

The LMWHs differ from heparin in that they are?

Answer 21

much more specific for activated factor X (Xa) than for activated factor II (IIa, or thrombin). This property gives LMWHs a much more predictable anticoagulant response. As a result, frequent lab monitoring of bleeding times using tests such as activated partial thromboplastin time (aPTT), which is imperative with unfractionated heparin, is not required with them

Question 22

Warfarin (Coumadin) works by?

Answer 22

inhibiting vitamin K synthesis by bacteria in the gastrointestinal (GI) tract. This, in turn, inhibits production of clotting factors II, VII, IX, and X, which are known as vitamin K–dependent clotting factors. The final effect is prevention of clot formation. It is used prophylactically to prevent clots from forming; it cannot lyse preformed clots.

Question 23

• Fondaparinux (Arixtra) inhibits thrombosis by its specific action against factor Xa alone.
• Rivaroxaban (Xarelto) is a new oral-acting factor Xa inhibitor approved in 2011.

Answer 23

.

Question 24

There are also currently five antithrombin drugs that inhibit the thrombin molecules directly, one natural and four synthetic. The natural drug is human antithrombin III (Thrombate), which is isolated from the plasma of human donors. The synthetic drugs are lepirudin (Refludan), argatroban (Argatroban), bivalirudin (Angiomax), and dabigatran (Pradaxa).

Answer 24

.

Question 25

The ability of anticoagulants to prevent clot formation is of benefit in certain settings in which there is likelihood of clot formation, including?

Answer 25

MI, unstable angina, atrial fibrillation, use of indwelling devices such as mechanical heart valves, and conditions in which blood flow may be slowed and blood may pool, such as major orthopedic surgery or prolonged periods of immobilization, for example, hospitalization or even long plane rides.

Question 26

Warfarin is indicated for prevention of any of these events…

Answer 26

MI, unstable angina, atrial fibrillation, use of indwelling devices such as mechanical heart valves, and conditions in which blood flow may be slowed and blood may pool, such as major orthopedic surgery or prolonged periods of immobilization, for example, hospitalization or even long plane rides.
Warfarin is indicated for prevention of any of these events,
-whereas unfractionated heparins, LMWHs, direct thrombin inhibitors, and factor Xa inhibitors are used for both prevention and treatment.

Question 27

When heparin is used for flushing catheters (10-100 units/mL) no monitoring is needed

Answer 27

.

Question 28

LMWHs are also routinely used as anticoagulant bridge therapy in?

Answer 28

situations in which a pt must stop warfarin for surgery or other invasive medical procedures . The term bridge therapy refers to the fact that enoxaparin acts as a bridge to provide anticoagulantion while the pt must be off of his warfarin therapy

Question 29

Patients at risk for clots are given medications for?

Answer 29

DVT prophylaxis while in the hospital and after major surgery.

Question 30

Coagulation modifiers contraindications

Answer 30

For all
-known drug allergy
-acute bleeding process, or high risk for such an occurrance
Warfarin
-pregnancy
LMWHs
-indwelling epidural catheter; they can be given 2 hours after the epidural is removed. VERY important because LMWH with an epidural has been associated with epidural hematoma

Question 31

main complication of anticoagulation therapy

Answer 31

Bleeding is the main complication of anticoagulation therapy, and the risk increases with increasing dosages. Such bleeding may be localized or systemic.
-also depends on the nature of pt’s underlying clinical disorder & increased in pt’s taking high doses of aspirin or other drugs that impair platelet function

Question 32

One particular notable adverse effect of heparin is?

Answer 32

heparin-induced thrombocytopenia, which is also called heparin-associated thrombocytopenia (HIT)

• Two types of HIT:
  1) Type 1-gradual reduction in platelets; heparin therapy can be continued
  2) Type 2-acute fall in #of platelets (more than 50% reduction from baseline); heparin therapy discontinued
• greatest risk to pt with HIT is the paradoxical occurrence of thrombosis, something that heparin normally prevents or alleviates
• thrombosis that occurs in the presence of HIT can be fatal
• incidence of this disorder ranges from 5-15%
• direct thrombin inhibitors lepirudin and argatroban are both indicated for Tx of HIT

Question 33

Warfarin can cause?

Answer 33

Skin necrosis and “PURPLE TOES”

Question 34

Although the toxic effects of heparin, LMWH, and warfarin are hemorrhagic in nature, the management is?

Answer 34

different for each drug. Symptoms that may be attributed to toxicity or an overdose of anticoagulants are: hematuria, melena (blood in the stool), petechiae, ecchymoses, and gum or mucous membrane bleeding.
-In the event of heparin or warfarin toxicity, the drug is to be stopped immediately.

Question 35

Stopping heparin alone may be enough to reverse the toxic effects because of the?

Answer 35

drug’s short half-life (1 to 2 hours). In severe cases, intravenous injection of protamine sulfate is indicated.

• Protamine is a specific heparin antidote and forms a complex with heparin, completely reversing its anticoagulant properties. This occurs in as few as 5 minutes
• in general 1 mg of protamine can reverse the effects of 100 units of heparin
• protamine may also be used to reverse the effects of LMWHs; a 1mg dose administered for each mg of LMWH given (1mg protamine for 1 mg enoxaparin)
• too-rapid infusion of antidote may lead to acute hyptensive episodes, bradycardia, dyspnea, and transient feelings of warmth & flushing
• if heparin overdose resulted in large blood loss, REPLACEMENT with packed RBCs may be necessary

Question 36

In warfarin toxicity or overdose, the first step is to?

Answer 36

discontinue the warfarin. Because warfarin inactivates the vitamin K–dependent clotting factors and because these clotting factors are synthesized in the liver, it may take 36 to 42 hours before the liver can resynthesize enough clotting factors to reverse the warfarin effects.

• Giving vitamin K1 (phytonadione) can hasten the return to normal coagulation.
• dose & route of vit K depends on the situation and acuity (how quickly warfarin induced effects must be reversed)
• High doses of vit K (10 mg) given IV will reverse the anticoagulation within 6 hours
• give the lowest amount of vit K possible because one it is given, warfarin resistance will occur for up to 7 days; thus pt cannot be anticoagulated by warfarin during this period. In these cases either heparin or LMWH may be provided
• in acute situations with severe bleeding administer transfusions of human plasma or clotting factor concentrations
• there are two prothrombin complex concentrate products (Kcentra and Profiline) that can be used for life threatening bleeding from warfarin. Also be used to reverse bleeding seen with the new oral antiXa products
• normally vit K usual route, however when the international normalized ratio (INR) is very elevated and/or pt bleeding, vit K given IV
• risk for anaphylaxis when given IV; risk diminished by diluting it and giving it over 30 MINUTES

Question 37

Anticoagulants interactions

Drug interactions involving the oral anticoagulants are profound and complicated.

Answer 37

The main interaction mechanisms responsible for increasing anticoagulant activity include:

• enzyme inhibition of metabolism
• displacement of the drug from inactive protein-binding sites
• decrease in vitamin K absorption or synthesis by the bacterial flora of the large intestines
• alteration in the platelet count or activity.
• both aspirin and warfarin increase the risk for bleeding when given with heparin. However they are commonly given together in clinical practice. When a pt placed on IV heparin, it is recommended that warfarin is started at the same time. Recommendations are to continue overlap therapy of the heparin and warfarin for at least 5 days; the heparin is stopped after 5 days when the INR is above 2

Question 38

Anticoagulant drug: Enoxaparin (Lovenox)

Answer 38

• LMWH
• obtained by enzymatically cleaving large unfractionated heparin molecules into small fragments. These fragments have greater affinity for factor Xa than for factor IIa & higher degree of bioavailability & longer elimination half-life than unfractionated heparin
• lab monitoring (as done w/heparin) not necessary when it is given because of its greater affinity for factor Xa
• only injectable
• prophylaxis and Tx
• all LMWH have distinct advantage over heparin in that they do NOT require lab monitoring and can be given at home
• deadly medication error is to give heparin in combination with this (or any LMWH)
• DOUBLE check that enoxaprin and other anticoagulants are never given to same pt. One exception is that enoxaparin is often used with oral warfarin as overlap Tx for pulmonary embolus or DVT
• prefilled syringes in range of dosage forms
• prefilled & graduated prefilled syringes for one-time use ONLY & available with systems that shield the needle after injection. AIR BUBBLE should NOT be expelled from prefilled syringes, as it’s designed to remain next to the plunger to ensure whole dose administered
• when used therapeutically it is dosed based on body weight in kilograms (like heparin) so be careful not to double dose

Question 39

Anticoagulant drug heparain

Answer 39

• obtained from lungs or intestinal mucosa of pigs
• Hep-Lock (small vials of IV flush solutions) used to maintain the patency of heparin-lock IV insertion sites
• due to risk of developing HIT, most use normal saline (0.9% sodium chloride) as flush for heparin lock IV ports
• heparin flushes still used for central catheters
• don’t need to monitor flushing
• commonly used for DVT prophylaxis in dose of 5000 units 2-3 times/day subcutaneously. DON’T need to monitor for prophylaxis
• when used for Tx, given continuous IV infusion. Most weight (kilograms) based protocols. Potential DOUBLE DOSE ERROR if using pounds not kilograms
• When given IV infusion, frequent measurement of aPTT (every 6 hours until therapeutic effects are seen) is necessary
• other drugs affecting coagulation cascade can have ADDITIVE effects which may lead to bleeding
• Although warfarin can have additive effects; its commonly used with IV Heparin therapy. Started in first day or two
• available ONLY in injectable form in mult. strengths (10-40,000 units/mL)
• CHECK vials since there are different strengths/concentrations and they all look alike. Don’t kill someone

Question 40

Anticoagulant: Warfarin sodium (Coumadin)

Answer 40

• commonly prescribed oral anticoagulant. Available oral & IV
• careful monitoring of prothrombin time/international normalized ratio (PT/INR), which is degree that the pt’s blood coagulability have been reduced by drug
• normal INR w/out warfarin is 1; therapeutic INR w/warfarin ranges from 2-3.5, depending on indication for use (atrial fibrillation, thromboprevention, prosthetic heart valve
• pts older than 65 yrs may have lower INR threshold for bleeding complications so monitor
• about 1/3 pt’s receiving warfarin metabolize differently based on variations in certain genes, CYP2CP & VKORC1. Genetic testing can be done to find correct dosing. Maintenance determined by INR
• Warfarin interactions: amiodarone, fluconazole, erythromycin, metronidazole, sulfonamide antibiotics, & cimetidine. Aforementioned more common; combination will lead to 50% increase in INR
• when amiodarone added to warfarin therapy, warfarin is cut in half
• warfarin inhibits vit K-dependent clotting factors, so foods high in vit K may reduce warfarin’s ability to prevent clots. They don’t need to avoid them though, just have consistency in diet
• herbal products that interact with warfarin resulting in increased risk for bleeding include dong quai, garlic, and ginkgo. St johns wort decreases warfarins effect

Question 41

Because warfarin inhibits vit K-dependent clotting factors, how should the nurse educate the pt

Answer 41

Food high in vit K such as; leafy green vegetables (kale, spinach, collard greens). Most important aspect is consistency in diet so educate to maintain consistency in their intake of leafy green vegetables. They don’t need to avoid them
-one maintenance warfarin dose is established they can still eat greens, but they need to be consistent in their intake of green vegetables because either increasing or decreasing intake can affect INR

Question 42

Coagulation modifiers have a variety of uses, including the

following:

Answer 42

(1) prevention or elimination of clotting in a
peripherally inserted catheter
(2) maintenance of patency (without clotting) of central venous catheters
(3) clot preventionin coronary artery bypass grafting
(4) prevention of clotting after major vessel injury
(5) treatment of thrombophlebitis to prevent venous and/or arterial thromboembolism
(6) prevention of clotting with use of prosthetics (e.g., heart valve replacements) and in atrial fibrillation.

Question 43

Nursing assessment: Perform a thorough patient assessment to identify the presence of risk factors, including

Answer 43

1) immobility
2) history of limited activity or prolonged bed rest (longer than 3 days)
3) dehydration
4) obesity
5) smoking
6) CHF
7) mitral or aortic stenosis
8) coronary heart disease w/documented atheroscleroiss or arteriosclerosis
9) peripheral vascular disease
10) pelvic, gynecologic-genitourinary, abdominal, orthopedic, or vascular major surgery
11) heart valve incompetency or replacement
12) history of thrombophlebitis
13) DVT or thomboembolism (MI, pulmonary, atril fibrillation)
14) edema of periphery
15) trauma to lower extremities
16) oral contraceptives
17) extended air flight time

Question 44

Because of the effects of anticoagulants it is important to assess

Answer 44

the skin, oral mucous membranes, gums, urine, and stool for any evidence of bleeding. Assess patients for any blood in the urine or stool, easy bruising, excessive bleeding from toothbrushing or shaving, or unexplained nosebleeds while receiving these medications, and report any such findings.

Question 45

With the use of coagulation modifier drugs the lab tests most ordered are?

Answer 45

Taken BEFOR and DURING therapy

• baseline CBC
• hemoglobin level
• hematocrit
• lipoprotein fractionation
• triglyceride
• cholesterol levels
• various clotting studies
• liver function tests

Question 46

Nursing assessment for heparin: with heparin and LMWH, it is critical to patient safety to continually assess what?

Answer 46

The skin to identify potential subcutaneous injection sites. For these sites AVOID any area w/in 2 inches of the umbiliucs, open wounds, scars, open or abraded areas, incisions, drainage tubes, stomas, or areas of bruising or oozing

• this sites=higher risk for further damage
• CORRECT site placement for injection of subcutaneous heparin or LMWH include: upper, outer area of the arms, thigh, subcutaneous fatty area across lower abdomen and between the iliac crest

Question 47

Nursing assessment: With the use of parenteral heparin, the ensure patient safety and prevent injury what should the nurse do?

Answer 47

Don’t give if pt has:
severe HTN, ulcer disease, ulcerative colitis, aneurysms, malignant HTN, alcoholism, head injuries. These are conditions in which a bleed is potential and possibly precipitated by parenteral anticoagulation
-important precaution for heparin use is pregnancy & lactation; however if needed during pregnancy can give but NOT warfarin

Question 48

It is crucial to patient safety to remember that heparin is not interchangeable unit for unit with drugs in another class of?

Answer 48

anticoagulants, the LMWHs. Heparin sodium contains

benzyl alcohol; therefore, assess for allergy to this additional component.

Question 49

When assessing the medication profile, a potentially deadly medication error is to give heparin in combination with?

Answer 49

enoxaparin (or any LMWH)

-always DOUBLE CHECK to make sure that heparin is NEVER given with enoxaprin simultaneously

Question 50

LMWHs contain?

Answer 50

Benzle alcohol and sulfites so assess for pt allergies

Question 51

Are LMWH interchangeable?

Answer 51

NO. Because they differ from standard heparin and other LMWHs
-may be used in outpatient therapy because they require LESS monitoring than heparin. Assess results of clotting studies PRIOR to therapy

Question 52

The oral warfarin: Because of the drugs action, withdrawl warfarin (as with all drugs altering bleeding/clotting) as ordered, BEFORE pt undergoes any dental procedure or if there is any evidence of?

Answer 52

tissue necrosis, gangrene, diarrhea, intestinal flora imbalanes, or steatorhea

Question 53

Important to emphasize that warfarin is indicated for?

Answer 53

Prophylaxis and long term tx of a variety of thromboembolic disorders and constant and skillful assessment of the patient and clotting results is required

Question 54

Most prescribers use standard protocols for warfarin to assist in dosing the drug based on PT/INR. The most common starting dosage is?

Answer 54

5mg daily. However dose can range from 1-10

• adults: 1-5 mg orally everyday
• important to know pharmacokinetics for warfarin because if pt is placed on IV heparin and warfarin is prescribed it will take several days for the warfarin to have a therapeutic effect.
• Continue overlap of warfarin & heparin for at least 5 days; heparin is stopped after 5 days when the INR is above 2

Question 55

Because Aspirin, NSAIDs, and other antiplatelet drugs alter bleeding times, the nurse should?

Answer 55

Withhold these drugs as ordered for 5-7 days BEFORE the pt undergoes surgical procedures

Question 56

Aspirin is not to be used in?

Answer 56

children and teenagers, in patients with any bleeding disorder, in pregnant or lactating women, or in patients with vitamin K deficiency or peptic ulcer disease.
-if used it could cause Reye’s syndrome in children & teenagers, teratogenic effects in pregnant women, & ulcers or bleeding tendencies in pt’s with vit K deficiency or peptic ulcer disease

Question 57

Perform a baseline cardiovascular assessment with antiplatelet (Clopidogrel), and document any?

Answer 57

Preexisting chest pain, edema, HA, dizziness, epistaxis, or flulike symptoms

• lab values: CBC, hemoglobin level & hematocrit, platelet counts, and PT and INR values
• if platelet count falls at or below 80,000 cells/mm notify prescriber; therapy will most likely not be initiated or will be discontinued

Question 58

Critical thinking: Do NOT administer two antiplatelet drugs at same time, do NOT give a thrombolytic drug with heparin, warfarin, aspirin, or NSAID

Answer 58

.

Question 59

Thrombolytics require similar assessments, including attention to baseline CBC and results of clotting studies. Additional concerns include a history of?

Answer 59

Hypotension & cardiac dysrhythmias

Question 60

Thrombolytic drug: Alteplase carries major concerns/cautions, contraindications, and drug interactions. Constantly assess any?

Answer 60

Arterial punctures, venous cut down sites, peripherally inserted central catheter sites, and central infusion ports or sites for bleeding

• Do NOT use IM injections in ANY situation, as they pose problems with bleeding
• as with any drugs altering clotting & platelet activity, the thrombolytics are associated with the risk for bleeding from wounds or from GI, GU, or respiratory tract, so assess any drainage, urine, stool, emesis (vomiting), sputum, and secretions for the presence of blood

Question 61

Antifibrinolytics require the same skillful assessment of baseline parameters and laboratory testing; however, there are additional concerns for patients with?

Answer 61

dysrhythmias, hypotension, bradycardia, convulsive disorders, nausea, vomiting, and abdominal pain or diarrhea. Prescriber may need to decrease dose

Question 62

Nursing implementation: Routinely monitor vital signs, heart sounds, peripheral pulses, and neurologic status in all patients during and immediately after anticoagulant therapy. What changes will be present that may indicate bleeding or hemorrhage?

Answer 62

If there is any change in pulse rate or rhythm, BP, or level of consciousness, and/or unexplained restlesness occurs

Question 63

Heparin may be given by the?

Answer 63

Subcutaneous or IV routes, but NOT IM. You can avoid inadvertent IM injection if you use only subcutanious syringes to withdraw and administser

• the 25-28 guage, 1/2” (1.5 cm) needle is often pre-packaged with the syringe
• No major harm results if subcutaneous dose inadvertently administered IV
• if rapid anticoagulation is needed, IV heparin by continuous or intermitten infusion may be prescribed
• monitor daily clotting study results,
• Do NOT aspirate before injecting to prevent hematoma formation

Question 64

The antidote to hemorrhage or uncontrolled bleeding resulting from heparin or LMWH therapy is?

Answer 64

protamine sulfate (can give IV); with subcutaneous heparin, several doses of it may be needed

Question 65

Administer LMWHs by subcutaneous injection where?

Answer 65

Deep into the injection site using same techniques for heparin

• rotate sites frequently
• avoid asparation with subcutaneous injections to prevent hematoma formation & tissue injury
• to avoid bruising do NOT massage the site after injection
• Pre-filled syringes of LMWHs are available for inpatient use and for at home tx
• solutions clear-pale yellow
• therapy length=5-10 days
• CBC, platelet counts, stool tests for occult blood
• blood in stool=AE of LMWH or any clotting altering drug

Question 66

Therapeutic levels of anticoagulants and other clotting-

altering drugs or coagulation modifier drugs are also monitored by laboratory studies such as?

Answer 66

aPTT, PT, and INR.

Question 67

Some of the therapeutic effects include?

Answer 67

decreased chest pain and a decrease in dizziness as well as in other neurologic symptoms.

Question 68

Adverse effects of anticoagulants include?

Answer 68

• bleeding and hematoma formation (heparin);
• thrombocytopenia (heparin and LWMHs);
• bleeding, dizziness, shortness of breath, and fever (direct thrombin inhibitors);
• bleeding, hematoma, dizziness, and GI distress (selective factor Xa inhibitors)
• bleeding, lethargy, and muscle pain (warfarin)
• Early signs of drug overdose for any of the clotting-altering drugs (i.e., anticoagulants) include bleeding of the gums during toothbrushing, unexplained nosebleeds or bruising, and heavier-than-usual menstrual bleeding.

Question 69

IV Heparin administration

Answer 69

• double check
• for continuous IV administration, an IV pump must be used to ensure a precise rate of infusion
• continuos dosing NOT intermittent
• tx by continuous IV infusion begins with loading dose followed by maintenance dose. Pt’s aPTT & other clotting studies are parameters for dosing
• for intermittent infusions a heparin lock used in the past. Heparin locks now referred to as intermittent infusion locks or saline locks because locks are flushed w/isotonic saline and not with heparin; exception PICC lines and central lines
• intermittent infusion given every 4-6 hrs due to heparins short half life. Needleless systems used for intermittent infusions and other types of IV
• crucial to check IV site to determine whether infiltration has occurred so that hematoma formation may be prevented. If suspected, remove the lock & replace at a new site before the next scheduled infusion
• therapeutic dosing of heparin guided by aPTT w/targeted level of 1.5-2.5 times the control (normal) value. Measured 24 hrs beginning therapy, 24-48 hrs after the start of therapy, 1-2 times weekly for 3-4weeks. With long term therapy aPTT monitored 1-2 times/month

Question 70

Oral anticoagulant administration

Answer 70

• scored tabs can be crushed given w/or w/out food
• many more drugs interact with oral anticoagulants than with heparin, especially those high in protein bound
• warfarin doses calculated based in INR values. INR also used to monitor effectiveness of therapy
• administered same time every day=maintain steady blood levels

Question 71

For conversion from heparin to an oral anticoagulant such as warfarin, the dose of the oral drug is the usual initial dosage amount, with the prescriber using the PT/INR levels to determine appropriate dosing of warfarin. Once continuous therapeutic anticoagulant coverage and warfarin has reached therapeutic levels, the heparin or LMWH may be discontinued without tapering. If uncontrolled bleeding occurs with any of these medications the nurse should?

Answer 71

Take action to control bleeding, institute emergency measures to stabilize pt’s condition and contact prescriber

Question 72

The aPTT and hematocrit levels are generally used as ordered to monitor?

Answer 72

Bleeding, clotting, and risk for bleeding. Always monitor the pt, especially for any changes in BP and pulse rate

Question 73

The antidote to oral anticoagulant (warfarin sodium) therapy is?

Answer 73

Vitamin K. When given IV, vit K may lead to anaphylaxis with resultant dyspnes, dizziness, rapid/weak pulse, chest pain, & hypotension which may progress to cardiac arrest or shock

Question 74

For antiplatelet drugs (or any clotting altering drugs) what should you monitor for?

Answer 74

S/S of bleeding during and after their use including:

-epistaxis, hematuria, hematemesis, easy or excessive bruising, blood in stool, bleeding of gums

Question 75

Enteric-coated aspirin is best taken?

Answer 75

With 6-8 oz of water & food to avoid GI upset

• instruct pt to remain upright & do not lie down for 30 min to avoid irritation to esophagus
• if it has a strong, vinegar-like odor discard it
• Interventions with clopidogrel (antiplatelet) therapy similar to aspirin
• report: aches in joints, back pain, dizziness, severe HA, dyspepsia, flu-like symptoms & epigastric pain
• these drugs discontinued for 7 days PRIOR to surgery. Some procedures (cardiovascular surgery) may warrant pt remain in anticoagulated state

Question 76

Thrombolytics: avoid invasive procedures during therapy . Avoid simultaneous use of anticoagulants or antiplatelets. Frequently monitor IV infusion sites for?
-IM injections with other drugs?

Answer 76

bleeding, redness, pain

-IM injections with other drugs contraindicated to prevent tissue damage & bleeding

Question 77

Thrombolytic therapy: Report bleeding from?

-Advise pt’s to report?

Answer 77

Gums, or mucous membranes or occurrence of epistaxis or increased pulse & monitor VS
-report any pink, red, cloudy urine; black tarry stools or frank red blood in stools; abdominal or chest pain; dizziness; or severe HA

Question 78

What should the nurse continually monitor after administration of thrombolytics?

Answer 78

INR, aPTT, platelet counts, & fibrinogen levels, beginning no later than 2-3 hrs after administration

• measure fibrinogen level to check occurrence of fibrinolysis
• w/breakdown of fibrin (or fibrinolysis), INR will increase and aPTT will be prolonged
• if bleeding occurs most likely discontinue drug & replace fibrinogen through infusions of whole blood plasma or cryoprecipitate. The antifibrinolytics aminocaproic acid and/or tranexamic acid may also be given

Question 79

with antifibrinolytics they stop bleeding from overdosages of?

Answer 79

thrombolytic drugs or to control bleeding during cardiac surgery