Ch 25 Coagulation Flashcards
What is the expected pharmalogical action of anticoagulants
Prevent clotting by activating anti thrombin and factor xa. This inhibits fibrin formation
What are the therapeutic uses of heparin
Stroke
Pulmonary embolism
Massive DVT
treatment for dissiminated intravascular coagulation (DIC)
What is the use of LMWH
Prevent DVT in post op patients
Treat DVT and PE
PRevemt complications in certain types of myocardial infarctions
What are activated X ( Xa) inhibitors used for
Fondaparinux
Prevents DVT & PE in post op clients
Treats DVT & PE in conjunction with warfarin
What is true of heparin and LMWH
These meds cannot be absorbed by the intestinal tract
They use be given SC or IV
What are possible complications of heparin
HEMMORRHAGE, secondary to heparin overdose Heparin induced thrombocytopenia AEB low platelet counts and increased development of thrombi Hypersensitivity reactions ( chills, fever, urticaria) Toxicity, overdose
For heparin toxicity what drug should be administered
Administer protamine. Administer is slowly Intravenously no faster than 20mg/min or 50mg/ 10 min.
Do not exceed 100 mg in a. 2 hr period
What platelet counts indicated that heparin needs to be discontinued
Less than 100,000
Adverse effects of enoxaparin
HEMMORRHAGE
Neurological damage from hematoma formed during spinal or epidural anesthesia.
Thrombocytopenia AEB platelet count less than 100,000
Toxicity/ overdose
What are adverse effects of fondaparinux
HEMMORRHAGE
Neurological damage from hematoma formed during spinal or epidural anesthesia
Thrombocytopenia
What are contraindications and precautions of parenteral anticoagulants
Contraindicated in ppl with low platelet counts
These meds should not be used during or following surgeries of the eye, brain, spinal cord; lumbar puncture, or regional anesthesia.
Uses cautiously in ppl who have hemophilia, increased capillary permeability, dissecting aneurysm, peptic ulcer disease, severe hypertension, heparin and renal disease or threatened abortion
What are nursing considerations for heparin
Obtain baseline vitals
Obtain & monitor CBC, HCT, and platelet count
Monitor rate of infusion Q 30-60 min
Monitor aPTT Q 4-6 hr until appropriate dose Is determined
For sc injections, use a 20-22 guage to withdraw med from vial, then switch to a smaller 25-26 guage.
Do not aspirate
Instruct client to avoid OTC NSAIDS, aspirin or meds containing salicylates
What is true of enoxaparin/ fondaparinux
Monitoring is not required
Acceptable for home use
How can one determine the effectiveness of heparin
aPTT levels of 60-80 seconds
Name a oral anticoagulant
Warfarin ( Coumadin)
What does warfarin do
It antagonizes vitamin K, thereby preventing the synthesis of 4 coagulation factors: factor VII,IS,X and prothrombin.
It treats venous thrombosis
It treats thrombus formation in ppl who have atrial fibrillation or prosthetic heart valves
It prevents recurrent MI, TIA, PE & DVT
What are complications of warfarin
HEMMORRHAGE
Hepatitis
Toxicity overdose
For toxicity or overdose of warfarin what should be administered
Vitamin k to promote synthesis of coagulation factors VII, IX, X and prothrombin
If vitamin k can’t control the bleeding administer fresh frozen plasma or whole blood
What are contraindications and precautions of warfarin
Pregnancy category X, due to the high risk of fetal HEMMORRHAGE, fetal death and CNS defects
Contraindicated in ppl with low platelet counts or uncontrolled bleeding
Contraindicated in surgeries of the eyes, brain or spinal cord; lumbar puncture or regional anesthesia.
Contraindicated in ppl with vitamin k deficiencies, liver disorders, and alcohol use disorders due to the additive risk of bleeding
Contraindicated in ppl with hemophilia, dissecting aneurysm, peptic ulcer disease, severe hypertension, or threatened abortion
What are medication interactions of warfarin
Concurrent use of heparin, aspirin, acetaminophen, glucocorticoids, sulfonamides, and parenteral cephalosporins increases the effects of warfari, which increases the risk for bleeding.
What are medication Interactions of warfarin
Concurrent use of Phenobarbitol, carbamazepine ( Tegetrol) phenytoin ( Dilantin), oral contraceptives and vitamin k decreases anti coagulation effects
If used concurrently monitor carefully for reduced PT and INR levels
What are food interactions of warfarin
Foods high in vitamin K, such a dark green leafy vegetables ( lettuce, cooked spinach) cabbage, broccoli, Brussels sprouts, mayonnaise, canola!and soybean oil,decrease anticoagulant effects with excessive intake.
What are therapeutic levels of PT
18-24 seconds
What are nursing considerations for the administration of warfarin
administration is usually orally, once daily at the same time each day
Obtain baseline vital signs
Monitor PT levels and INR levels ( INR levels are the most accurate)
Obtain baseline and monitor CBC, platelet count, and HCT levels
What are therapeutic levels of INR
2-3
How can one tell that warfarin is effective
PTT is 1.5-2 times the control
INR of 2-3 for treatment of acute MI, atrial fibrillation, PE venous thrombosis and or tissue heart valves
INR of 3-4.5 for mechanical heart valve or recurrent systemic embolism
No development of venous thrombi.
What are anticoagulants (PARENTERAL)
Heparin
LoW molecular weight heparins (LMWH)
Prototype: enoxaparin (Lovenox)
Other meds; dalteparin (Fragmin),
Tinzaparin ( Inmohep)
Activated factor x ( xa) inhibitor
Prototype: fondaparinux ( Arixtra)
