Pharmacolgoy Exam 3 - Chapt 27

Front 1

What is the primary purpose of anticoagulant therapy?

Back 1

The anticoagulants such as warfarin, heparin, & heparin derivatives (ardeparin, enoxaparin, dalteparin)are used prophylactically to prevent formation of arterial & venous thrombi in predisposed patients. The simply prevent new clot formations or the extension of existing clots. They cannot dissolve an existing clot.

Front 2

The heparin derivatives are also known as?

Back 2

Low-molecular-weight heparins (LMWHs).

Front 3

The specific action of warfarin (Coumadin) is to block:

Back 3

The production factors VII, IX, X, and II by the liver, which is controlled by Vit K. Warfarin sodium blocks the action of Vit K within the liver.

Front 4

The specific action of heparin include:

Back 4

Acts as a catalyst to accelerate the rate of action of a naturally occurring inhibitor of thrombin, antithrombin III (hep cofactor).

Front 5

The specific action of fibrinolytic agents:

Back 5

Work by stimulating the body's own clot-dissolving mechanism,converting plasminogen,a naturally occurring substance secreted by endothelial cells in response to injury of the artery, to plasmin (AKA,fibrinolysin),which digests fibrin.

Front 6

What are the (5) fibrinolytic agents:

Back 6

1)streptokinase (Kabikinase)
2)urokinase (Abbokinase)
3)alteplase (recombinant plasminogen activator[rtPA])(Activase)
4)reteplase (rtPA)(Retavase)
5)tenecteplase (rtPA)(TNKase) "Clot Buster"

Hint 6

Meet the ase's!

Front 7

Nursing interventions to prevent clot formation:

Back 7

1)ambulation after surgery
2)turn complete bed rest pts
3)do not flex knees or place pressure against the poplietal space w/pillows.
4)Do not allow pt to stand or sit for long periods of time.
5)Use TED hose/stockings
6)Apply SCDs (sequential compression device) as ordered & indicated. Ensure proper application!

Front 8

Specific monitoring procedures to detect hemorrhage in a pt taking anticoagulants:

Back 8

Monitor vital signs & mental status q 4-8h or more frequently depending on pt status. Observe for S&S of bleeding (e.g.,blurred vision, hematuria, ecchymosis, occult blood in stools, change in mentation).

Hint 8

If only I knew at the time!

Front 9

What is the procedure used to ensure that the correct dose of an anticoagulant is prepared & administered?

Back 9

1)Never administer without first checking recent lab results.
2)Be certain that the anticoagulant to be administered is ordered after the most recent results have been reported to the MD.
3)Follow policy statements regarding checking of anticoagulant doses w/ other qualified professionals.
4)Reduce localized bleeding by using smallest needle possible & rotate site.

Front 10

What is the specific procedure/technique used to administer heparin subcutaneously:

Back 10

1)SQ injection is usually given in the tissue over the abdomen.
2)Do NOT inject within 2 inches of the umbilicus.
3)Do NOT massage injection site before or after.
4)Rotate the site to prevent the development of a massive hematoma.
5)Use a 26- or 27- gauge,1/2 in needle,depending on pt size. TB syringe. 90 degree angle.
6)DO NOT Aspirate!
7)DO NOT inject into a hematoma/infection.
8)Apply gentle pressure for 1-2 minutes after injection.
9)Ice packs have not been proven to prevent a hematoma or affect drug absorption.

Front 11

What is the specific procedure/technique used to administer heparin intravenously:

Back 11

Initially 70 to 100 units/kg bolus;maintenance 15 to 25 units/kg/hr. Periodic dosage adjustment is required based on the pts response. Loading doses are rounded to the nearest 500 units & maintenance infusion rates to the nearest 100 units.When preparing a solution for infusion, always have 2 nurses confirm calculations & strength.Never make infusions that run more than 6 to 8 hrs,this prevents "run away" infusions.Monitor infusion q 30 to 60 minutes.

Front 12

What is the specific procedure/technique used for intermittent administration of heparin via a heparin lock:

Back 12

1)22- to 29- gauge scalp vein needle attached to a 3 1/2-in tubing ending in a resealing rubber diaphragm.
2)After injecting a bolus of heparin through the rubber diaphragm, flush line w/ 1ml of saline sol, this ensures pt is getting full dose & prevents formation of clot in needle.

Front 13

Heparin antidote:

Back 13

1 mg of protamine sulfate will neutralize approximately 100 units of heparin. If given more than 30 minutes after the heparin was administered, give only half the dose. Because excessive doses of protamine may also cause excessive anticoagulation, it must be used sensibly.

Front 14

Thromboembolic disease:

Back 14

Disease associated w/ abnormal clotting within blood vessels.

Front 15

Thrombosis:

Back 15

The process of formation of a fibrin blood clot (thrombus).

Front 16

Embolus:

Back 16

A small fragment of a thrombus that breaks off & circulates until it becomes trapped in a capillary, causing either ischemia or infarction of the area distal to the obstruction.

Front 17

Intrinsic Clotting Pathway:

Back 17

One of the phases that generates thrombin. This phase is triggered by the presence of collagen activating factor XII. The intrinsic pathway is activated when blood comes into contact with sub-endothelial connective tissues or with negatively charged surface that are exposed as a result of tissue damage.

Hint 17

Slower than extrinsic.

Front 18

Extrinsic Clotting Pathway:

Back 18

Provides a very rapid response to tissue injury, generating activated factor X almost instantaneously, compared to the seconds or even minutes required for the intrinsic pathway to activate factor X. The main function of the extrinsic pathway is to augment the activity of the intrinsic pathway.

Front 19

Platelet inhibitors:

Back 19

1)aspirin-platelet aggregation inhibition w/prolongation of bleeding time.
2)dipyridamole (Persantine)-Platelet-adhesiveness inhibitor that is thought to inhibit thromboxane A2.
3)clopidogrel (Plavix)-inhibits the ADP pathway required for platelet aggregation.
4)ticlopidine (Ticlid)-Inhibits the ADP pathway required for platelet aggregation.

Hint 19

Platelet lifetime = 7 to 10 days

Front 20

Anticoagulants:

Back 20

dalteparin (Fragmin)-the second (after enoxaparin) of the LMWHs. Enhances antithrombin activity against factor Xa & thrombin, which prevents completion of the coagulation cascade.
2)enoxaparin (Lovenox)-Active against factor Xa & thrombin;preventing completion of the coagulation cascade.
3)Fondaparinux(Arixtra)-a selective factor Xa inhibitor that binds to antithromin III.
4)heparin-is a natural substance extracted from gut/lung tissue of pigs & cattle. In full therapeutic doses, heparin acts as a catalyst to accelerate the rate of action of a naturally occurring inhibitor of thrombin, antithrombin III (hep cofactor). Heparin also inhibits activation of factor VIII, the fibrin stabilizing factor,preventing soluble fibrin clots from becoming insoluble clots.
5)tinzaparin (Innohep)-Enhances antithrombin activity against factor Xa & thrombin,preventing completion of coagulation cascade.
6)warfarin (Coumadin)-inhibits activity of Vit K.

Front 21

Observing for signs of what is a priority assessment while treating with urokinase?

Back 21

Intracranial bleeding.

Front 22

Patients taking clopidogrel should report what signs & symptoms?

Back 22

Fever, sore throat, & excessive fatigue that can be caused by an onset of neutropenia.

Front 23

What is neutropenia and which drugs can cause it?

Back 23

Neutropenia is an abnormally low count of neutrophils (<2000) of the WBCs. Clopidogrel can cause neutropenia.

Front 24

The use of heparin should be avoided in patients with?

Back 24

Peptic Ulcer Disease.

Hint 24

Risk for GI Bleed!

Front 25

Heparin prevents:

Back 25

The formation of thrombi (clot).