Hemostasis Drugs

Question 1

Anticoagulants

Answer 1

Prevent clot formation and DECREASE BLOOD COAGULABILITY

HAVE NO DIRECT EFFECT ON A BLOOD CLOT THAT IS ALREADY FORMED

PROPHYLAXIS for thrombi and emboli caused by smoking, HTN, immobility

Question 2

Antiplatelets

Answer 2

Prevent platelet plugs

Question 3

Thrombolytic Drugs

Answer 3

“Clot busters”

Lyse existing clots

Question 4

Antifibrinolytic or Hemostatic Drugs

Answer 4

Promote blood coagulation

Used for hemophilia

Question 5

Heparin Action

Answer 5

Prolong coagulation time

FREQUENT LABORATORY MONITORING FOR BLEEDING TIMES SUCH AS aPTT

Used only in a hospital setting

Subcutaneous, IV bolus –> IV infusion

Question 6

Enoxaparin (Lovenox)

Answer 6

LMWH

Synthetic smaller molecular structure

More for prophylaxis

Frequent laboratory monitoring NOT NEEDED

Given subcutaneously in the abdomen

DO NOT RUB

Question 7

Warfarin (Coumadin) Action

Answer 7

Inhibits vitamin K synthesis by bacteria in the GI tract

Prevents clot formation

Question 8

Direct Thrombin Inhibitor

Answer 8

Dabigatran (Pradaxa)

Question 9

Selective Factor X Inhibitor (Thrombin Inhibitor)

Answer 9

Ivaroxaban (Xarelto)

Question 10

Anticoagulant Drug Effects

Answer 10

Prevent intravascular thrombus by decreasing blood coagulability

Do not lyse existing clots

Question 11

Anticoagulant Indications

Answer 11

MI, unstable angina (precursor to MI), atrial fibrillation, indwelling devices (i.e. mechanical heart valves), major orthopedic surgery

Question 12

Anticoagulant Contraindications

Answer 12

Warfarin CANNOT be taken during pregnancy (Heparin is okay)

LMWHs ARE CONTRAINDICATED IN PATIENTS WITH AN INDWELLING EPIDURAL CATHETER OR RISK OF EPIDURAL HEMATOMA

Question 13

Treatment of Toxic Effects of Heparin

Answer 13

Symptoms: hematuria, melena, petechiae, ecchymoses

Stop drug immediately

1 mg of protamine can reverse the effects of 100 units of Heparin

Question 14

Treatment of Toxic Effects of Warfarin

Answer 14

Discontinue Warfarin

Vitamin K1 (phtonadione) can hasten the return of normal coagulation

When vitamin K is given, Warfarin resistance will occur for up to 7 days

Question 15

Heparin

Answer 15

Does not need to be monitored when used for prophylaxis

Therapeutic use: continuous IV infusion; short half life (1-2 hours)

MEASUREMENT OF aPTT (every 6 hours until therapeutic effects are seen) IS NECESSARY

High alert drug; two nurses must check dosage

Question 16

Warfarin

Answer 16

Most commonly prescribed oral anticoagulant

Is not effective for 1-2 days

CAREFUL MONITORING OF THE PROTHROMBIN TIME/INTERNATIONAL NORMALIZED RATIO (PT/INR)

Normal INR is 1.0, therapeutic range goes from 2-3.5

Watch intake of vitamin K

Question 17

Antiplatelet Actions

Answer 17

Inhibit platelet adhesion and aggregation by blocking receptor sites on the platelet membrane

Reduce risk of recurrent TIAs or strokes; reduce death or nonfatal MI

Used in addition to/instead of anticoagulant

Aspirin and Clopidogrel (Plavix)

Question 18

Antiplatelet Contraindications

Answer 18

Pregnancy, lactation

Caution with bleeding disorders, recent surgery (alters healing), closed-head injury

Question 19

Adverse Effects of Antiplatelets

Answer 19

Bleeding, headache, GI distress (peptic ulcers)

Question 20

Thrombolytic Drugs

Answer 20

Streptokinase and Alteplase (Activase)

Drugs that break down or lyse clots

Question 21

Thrombolytic Indications

Answer 21

Acute MI, DVT, occlusion, pulmonary embolus

Question 22

Antifibrinolytic Drugs

Answer 22

Prevent lysis of fibrin

Result in promoting clot formation

TREATMENT OF HEMOPHILIA OR VON WILLEBRAND’S DISEASE

AMINOCAPROIC ACID (AMICAR)

Question 23

Nursing Implications

Answer 23

IV doses should be double-checked

Subcutaneous doses given subcutaneously in areas of deep subcutaneous fat; sites rotated

Protamine sulfate is antidote for heparin

Vitamin K is antidote for warfarin

Warfarin may be started while still on heparin