Pharmacology - Final Exam - Chp 52

2

LMW heparin should be administered _ inches from the umbilicus.

1.1, 4.5

Normal people's INR should be 0.8-__. People on warfarin should have an INR of 2-3 and as high as __ in some cases.

C (The primary and most serious adverse effect of heparin is bleeding. Bleeding can occur from any site and may be manifested in various ways, including reduced blood pressure, increased heart rate, bruises, petechiae, hematomas, red or black stools, cloudy or discolored urine, pelvic pain, headache, and lumbar pain.)

A 63-year-old male patient has been receiving a heparin infusion for 2 days for treatment of pulmonary embolism. Which symptom most clearly relates to an adverse effect of heparin? A. Heart rate of 60 beats per minute B. Blood pressure of 160/88 mm Hg C. Discolored urine D. Wheezing

C (The INR is within a therapeutic range [2 to 3], so the nurse should call the health care provider to get the heparin infusion discontinued. An aPTT of 60 indicates the heparin is therapeutic with no indication that the patient has achieved the therapeutic effect of warfarin. The patient will be on a combination of heparin and warfarin until the therapeutic effect of warfarin has been achieved, and this may take several days. The patient will have no protective effect against clotting if the heparin is reversed with protamine sulfate and the INR is not within a therapeutic range.)

A patient admitted with atrial fibrillation is receiving a continuous heparin infusion as well as daily warfarin (Coumadin). What is an appropriate action by the nurse? A. Contact the healthcare provider for an order to stop the heparin, because the aPTT is 60 seconds. B. Contact the healthcare provider to request discontinuation of the heparin, because the patient is receiving Coumadin. C. Notify the healthcare provider that the INR is 3 and anticipate that the heparin will be discontinued. D. Prepare to administer protamine sulfate, because the patient has received two anticoagulants at the same time.

B, C, D (Measurement of the aPTT is essential to determine whether the heparin infusion is having the desired effect. If the normal value of the aPTT is 40 seconds, the goal is to achieve a therapeutic range of a factor of 1.5 to 2 [60 to 80 seconds]. Because 40 seconds is too short [increases the risk for clotting] and 100 seconds is too long [increases the risk for bleeding], the physician requires notification for adjustment of the infusion rate. Evidence of bleeding, such as nosebleeds, hematuria, and red or tarry stools, warrant a call to the physician. An aPTT of 65 seconds indicates that a therapeutic effect has been achieved, and a platelet count of 300,000/mcL is within normal limits, indicating no evidence of thrombocytopenia.)

A patient diagnosed with a pulmonary embolism is receiving a continuous heparin infusion at 1000 units/hr. Which situation would warrant a call to the physician? (Choose all that apply) A. aPTT of 65 seconds B. aPTT of 40 seconds C. Nosebleeds D. aPTT of 100 seconds E. platelet count of 300, 000/mcL

B (Heparin is an anticoagulant that works by helping antithrombin inactivate thrombin and factor Xa, reducing the production of fibrin and thus decreasing the formation of clots.)

A patient with deep vein thrombosis is receiving an intravenous (IV) heparin infusion. He asks the nurse how this medication will help him. The nurse's response is accurately based on which concept? A. Heparin prevents the activation of vitamin K and thus blocks synthesis of some clotting factors. B. Heparin suppresses coagulation by helping antithrombin perform its natural functions. C. Heparin works by converting plasminogen to plasmin, which in turn dissolves the clot matrix. D. Heparin inhibits the enzyme responsible for platelet activation and aggregation within vessels.

A (Dabigatran is unstable, especially when exposed to moisture, and should be stored in the manufacturer-supplied bottle, which has a desiccant cap. Current labeling of the pill bottle indicates that once the bottle is opened, the pills should be used within 30 days. However, recent evidence indicates that they maintain efficacy for 60 days, provided they have been stored in the original container. Capsules should be swallowed intact, because chewing, crushing, or opening enhances absorption by 75% and increases the risk of bleeding. The medication is administered orally, not subcutaneously.)

A patient with nonvalvular atrial fibrillation is to be discharged on dabigatran etexilate (Pradaxa). Which statement should the nurse include in the discharge teaching? A. "The medication must be stored in the manufacturer-supplied bottle." B. "Once a new bottle is opened, the capsules maintain efficacy for 90 days." C. "If you have difficulty swallowing the capsule, you can open it and mix it with food." D. "You will need to learn how to give yourself a subcutaneous injection in your abdomen."

inhibits

Acetaminophen should be avoided with warfarin because it _____ warfarin degradation.

hemorrhage

Adverse effects of warfarin include ____ and fetal hemorrhage and teratogensis is used in pregnancy.

10

Among patients on heparin, hemorrhage occurs in __% of patients.

platelets

An arterial thrombus forms when _____ adhere to the arterial wall; continued aggregation with occlude the artery.

fibrin, synthesis, activity

Anticoagulants reduce the formation of ____ by inhibiting _____ of clotting factors or by inhibiting the _____ of clotting factors (heparin)

aggregation

Antiplatelet drugs suppress the ______ of platelets which helps prevent thrombosis in arteries.

promotes

Aspirin should be avoided with warfarin because it _____ bleeding and ulcer formation.

40, 80

Normal aPTT is __ seconds; on heparin it should be 60-__ seconds.

allergic

Because heparin is extracted from animal tissues and may contain foreign antigens, the nurse should watch for ____ reactions.

molecular

Low-____-weight heparins are composed of molecules that are shorter than those found in unfractionated heparin.

more

LMW heparin costs ___ than unfractionated heparin.

weight

LMW heparin dosage is based on the patients ____.

B

First line therapy for DVT prevention following surgery. A. unfractionated heparin B. LMW heparin C. sildenafil D. fluroquinalones

parin

Generic names for LMW heparins end in ____.

protamine

Heparin antidote: _____ sulfate.

short

Heparin has a very ___ half-life.

clotting factors

Heparin inhibits the activity of ____ ____.

rapid

Heparin is a ____-acting anticoagulant.

rapid

Heparin is the preferred anticoagulant during pregnancy and when ___ anticoagulation is required.

B

If a patient on heparin is vomiting blood, the nurse should... A. give protamine sulfate and continue the heparin treatment B. give protamine sulfate and discontinue the heparin treatment C. notify the physician D. discontinue the heparin treatment

platelets

In stage 1 of hemostasis, the plug is formed when _____ aggregate.

fibrin

In stage 2 of hemostasis, the platelet plug is reinforced by ____.

immune, reduced

Patients on heparin need to have their platelet counts monitored due to a condition called heparin-induced thrombocytopenia (HIT), an ____ mediated disorder characterized by _____ platelet counts.

bleeding

Patients on heparin should be monitored closely for signs of ____.

partial, 2

Patients on heparin should have their activated _____ thromboplastin time (aPTT) monitored and it should not exceed _ times the control value.

prothrombin

Patients on warfarin will have their ____ time (PT) monitored as well as their INR (international normalized ratio).

collagen

Platelet aggregation is initiated when platelets come into contact with ____ on exposed surfaces of damaged blood vessels.

aspirin

Prototype anti-platelet drug.

enoxaparin (Lovenox)

Prototype drug from LMW heparin.

protamine

Similar to unfractionated heparin, the antidote for LMW heparin is ____ sulfate.

T

T/F: An adverse effect of the antiplatelet drugs aspirin is bleeding.

F (injection only [IV or deep sub q])

T/F: Heparin is administered only by mouth.

F

T/F: Warfarin can be used during emergencies.

81

The dosage of aspirin when used as an antiplatelet medication is __ mg.

A (Heparin-induced thrombocytopenia [HIT] is a potential immune-mediated adverse effect of heparin infusions that can prove fatal. HIT is suspected when the platelet counts fall significantly. A platelet count below 100,000/mm3 would warrant discontinuation of the heparin.)

The laboratory calls the nursing unit to report a drop in the platelet count to 90,000/mm3 for a patient receiving heparin for the treatment of postoperative deep vein thrombosis. Which action by the nurse is the most appropriate? A. Call the healthcare provider to discuss the reduction or withdrawal of heparin. B. Call the healthcare provider to discuss increasing the heparin dose to achieve a therapeutic level. C. Obtain vitamin K and prepare to administer it by intramuscular (IM) injection. D. Observe the patient and monitor the activated partial thromboplastin time (aPTT) as indicated.

B (The therapeutic level of heparin is achieved when the aPTT reaches 1.5 to 2 times normal. Thus, a range of 60 to 80 seconds would be appropriate for this patient.)

The nurse is beginning a heparin infusion for a patient with evolving stroke. The baseline activated partial thromboplastin time (aPTT) is 40 seconds. Which aPTT value indicates that a therapeutic dose has been achieved? A. 50 B. 70 C. 90 D. 110

A, C, E (Patients with genetic alterations in VKORC1 and CYP2CP are at increased risk of warfarin-induced bleeding. An INR of 2.2 indicates a therapeutic warfarin level. Warfarin can cause fetal hemorrhage and is listed as Pregnancy Risk Category X. Warfarin could be prescribed for the prevention of deep vein thrombosis after hip replacement surgery. The day of prescription would not likely be a day to expect a dangerous adverse effect from warfarin, because its half-life is 1.5 to 2 days. Warfarin interacts with many other agents. The greatest risk for harm is when an interacting drug is being added to or deleted from the regimen.)

The nurse is caring for a group of patients taking warfarin (Coumadin). Which patient or patients is/are at moderate to high risk for harm as a result of warfarin therapy? (Choose that apply) A. A 79-year-old man with variant genes that code for VKORC1 and CYP2CP B. A 50-year-old woman with a current INR of 2.2 treated for deep vein thrombosis C. A 26-year-old pregnant woman with new onset of symptoms of a pulmonary embolus D. A 65-year-old man on day 4 after hip replacement with a new order for warfarin E. A young adult with a prosthetic heart valve, for whom an interacting drug is being deleted from the regimen

B (Omeprazole and other proton pump inhibitors may reduce the antiplatelet effects of clopidogrel. Patients sometimes take them to reduce gastric acidity and the risk of gastrointestinal [GI] bleeding.)

The nurse is caring for a patient receiving clopidogrel (Plavix) to prevent blockage of coronary artery stents. Which other drug on the patient's medication administration record may reduce the antiplatelet effects of clopidogrel? A. Aspirin (Bayer) B. Omeprazole (Prilosec) C. Acetaminophen (Tylenol) D. Warfarin (Coumadin)

D (An INR in the range of 2 to 3 is considered the level for warfarin therapy. For a level of 1.2, the nurse should contact the healthcare provider to discuss an order for an increased dose.)

The nurse is caring for a patient who takes warfarin (Coumadin) for prevention of deep vein thrombosis. The patient has an international normalized ratio (INR) of 1.2. Which action by the nurse is most appropriate? A. Prepare to administer protamine sulfate. B. Continue with the current prescription. C. Prepare to administer vitamin K. D. Call the healthcare provider to increase the dose.

C (Enoxaparin acts primarily on factor Xa and also but to a lesser degree on thrombin. Unfractionated heparin equally reduces the action of thrombin and factor Xa. Fondaparinux [Arixtra] causes selective inhibition of factor Xa. Low-molecular-weight [LMW] heparins, such as enoxaparin, have greater bioavailability and a longer half-life than those of unfractionated heparin.)

The nurse knows that which statement is accurate for enoxaparin (Lovenox)? A. It equally reduces the activity of thrombin and factor Xa. B. It has selective inhibition of factor Xa and no effect on thrombin. C. It reduces the activity of factor Xa more than the activity of thrombin. D. It has a lower bioavailability and shorter half-life than unfractionated heparin.

A, B, C, E, F

Therapeutic uses of antiplatelet drugs included: (choose all that apply) A. angina B. TIA C. acute and previous MI D. priapism E. preventing MI F. ischemic stroke G. Legionnaire's disease

plasmin

This substance removes clots.

platelet

Ticlopidine and clopidogrel are both anti-____ drugs.

synthesis

Unlike heparin, which inhibits activity of clotting factors, warfarin inhibits the _____ of clotting factors.

dosage, aPTT (activated partial thromboplastin time)

Unlike unfractionated hepari, LMW heparin can be given using a fixed ____ and does not require monitoring ____.

intravenously

Unlike unfractionated heparin, LMW heparin cannot be given _____.

fibrin

Venous thrombosis develops where blood flow is slow and stagnates leading to ____ production causing RBCs and platelets to get caught.

K

Warfarin blocks the synthesis of clotting factors by blocking the actions of Vitamin _.

heparin

Warfarin has a long half-life but may take 3-5 days to reach full effect, therefore patients will continue taking ____ until the warfarin is fully on board.

oral

Warfarin is an anticoagulant that is given via the ____ route.

long

Warfarin is used for ___-term prophylaxis of thrombosis

rat

Warfarin used to be used as ___ poison.

A, C, D

What are the three major groups of drugs for thromboembolic disorders? A. antiplatelets B. anxiolytics C. thrombolytics D. anticoagulants

thrombus

What is a blood clot formed within the blood vessel or within heart known as?

150, 100

When monitored platelet counts for HIT, __-300k is normal and anything less than __ is cause for serious concern (HIT).

B (Heparin should be administered subcutaneously into the fatty layer of the abdomen with a ½- to ⅝-inch needle, 25 or 26 gauge. The only appropriate option for injection in the list shown is the ⅝-inch, 25-gauge needle.)

Which needle length and gauge should the nurse choose to administer subcutaneous heparin? A. ½ inch; 20 gauge B. ⅝ inch; 25 gauge C. 1½ inch; 18 gauge D. 1 inch; 26 gauge

heparin

____ is also given for pulmonary embolism (PE), stroke, and large deep vein thrombosis (DVT).

bleeding

____ is an adverse effect of LMW heparin but it is reduced compared to unfractionated heparin.