NURS 133 Warfarin and Heparin

jasmine's version from 2016-05-24 03:07

Section 1

Question Answer
Warfarin Anti-coagulant; Prophylaxis and treatment of venous thrombosis, pulmonary embolism, atrial fibrillation with embolization; Management of myocardial infarction: Decreases risk of death, decreases risk of subsequent MI, decreases risk of future thromboembolic events; Prevention of thrombus formation and embolization after prosthetic valve placement
Warfarin actions Interferes with hepatic synthesis of vitamin K-dependent clotting factors (II, VII, IX, and X)
Warfarin therapeutic uses Prevention of thromboembolic events; Used to prevent heart attacks, strokes, and blood clots
Elimination/Excretion of Warfarin Metabolized by the liver
Adverse/Side Effects of Warfarin Bleeding
Contraindications of Warfarin Uncontrolled bleeding; Open wounds; Active ulcer disease; Recent brain, eye, or spinal cord injury or surgery; Sever liver or kidney disease; Uncontrolled hypertension; OB: Crosses placenta and may cause fatal hemorrhage in the fetus; May also cause congenital malformation
Drug/Food interactions of Warfarin Abeiximab, androgens, capecitabine, cefotetan, chloramphenicol, clopidogrel, disulfiram, fluconazole, fluoroquinolones, itraconazole, metronidazole (including vaginal use), thrombolytics, eptifibatide, tirofiban, ticlopidine, sulfonamides, quinidine, quinine, NSAIDS, valproates, and aspirin may increase the response to warfarin and increase the risk of bleeding; Chronic use of acetaminophen may increase the risk of bleeding; Chronic alcohol ingestion may decrease action of warfarin-if chronic alcohol ingestion may decrease action of warfarin-if chronic alcohol abuse results in significant liver damage, action of warfarin may be increase due to decrease production of clotting factor-acute alcohol ingestion may increase action of warfarin; Barbiturates, carbamazepine, rifampin, and hormonal contraceptives containing estrogen may decrease the anticoagulant response to warfarin; Many other drugs may affect the activity of warfarin; St. John’s sort decreases effect; Increase bleeding risk with anise, arnica, chamomile, clove, dong quai, fenugreek, feverfew (Eurasian plant of the daisy family used to treat headaches), garlic ginger, ginkgo, Panax ginseng, licorice, and others; Ingestion of large quantities of foods high in vitamin K content may antagonize the anticoagulant effect of warfarin
Medication administration of Warfarin PO; IV
Nursing interventions of Warfarin Assess for signs of bleeding and hemorrhage (bleeding gums; nosebleed; unusual bruising; tarry, black stools; hematuria; fall in hematocrit or BP; guaiac-positive stools, urine, or nasogastric aspirate); Assess for evidence of additional or increased thrombosis; Geri: Patient over 60 years of age exhibit greater than expected PT?INR response-Monitor for side effects at lower therapeutic ranges; Pedi: Achieving and maintain therapeutic PT/INR ranges may be more difficult in pediatric patients-Asses PT/INR levels more frequently; PO: Administer medication at same time each day-medication requires 3-5 days to reach effective levels-usually begun whole patine is still on heparin; Lab test considerations: Monitor PT, INR and other clotting factors frequently during therapy; Asian patients and those who carry the CYP2C9*2 allele and/or the CYP2C9*3 allele, or those with VKORC1 AA genotype may require more frequent monitoring and lower doses; Monitor hepatic function and CBC before and periodically throughout therapy; Monitor stool and urine for occult blood before and periodically during therapy; Toxicity and overdose: Withholding 1 or more doses of warfarin is usually sufficient if INR is excessively elevated or if minor bleeding occurs; If overdose, antidote is vitamin K (Phytonadione, AquaMEPHYTON)-Administration of whole blood or plasma also may be required in severe bleeding due to delayed onset of vitamin K
Warfarin antidote Vitamin K
High Alert of Warfarin Medication errors involving anticoagulants have resulted in serious harm or death from internal or intracranial bleeding; before administering, evaluate recent INR or PT results and have second practitioner independently check original order; Due to large number of medications capable of significantly altering warfarin’s effects, careful monitoring is recommended when new agents are started or other agents are discontinued; Interactive potential should be evaluated for all new medications (Rx, OTC, and natural products)
Client education of Warfarin Instruct patient to take medication as directed, not to double dose, and to inform health care professional of missed doses at time of checkup or lab tests. Inform patient that anticoagulant effect may persist for 2-5 days following discontinuation. Advise patient to read Medication Guide before starting therapy and with each RX refill; Review foods high in vitamin K with patient-Patient should have consistent limited intake of these foods, as vitamin K is the antidote for warfarin, and alternating intake of these foods will cause PT levels to fluctuate-Advise patient to avoid cranberry juice or products during therapy; Caution patient to avoid IM injections and activities leading to injury. Instruct patient to use a soft toothbrush, not to floss, and to shave with an electric razor during warfarin therapy. Advise patient that venipunctures and injection sites require application of pressure to prevent bleeding or hematoma formation; Advise patient to report any symptoms of unusual bleeding or bruising (bleeding gums; nosebleed; black, tarry stools; hematuria; excessive menstrual flow) and pain, color, or temperature change to any area of body to heath care professional immediately. Patients with a deficiency in protein C and/or S mediated anticoagulant response may be at greater risk for tissue necrosis; Instruct patient not to drink alcohol or take other Rx, OTC, or herbal products, especially those containing aspirin or NSAIDS, or to start or stop any new medications during warfarin therapy without advice of health care professional; Advise patient to notify health care professional if pregnancy is planned or suspected or if breast feeding; Instruct patient to carry identification describing medication regiment at all times and to inform all health care professional caring for patient on anticoagulant therapy before lab tests, treatment, or surgery; Emphasize the importance of frequent lab tests to monitor coagulation factors
Evaluation/Desired outcomes of Warfarin Prolonged PT (1.3-2.0 times the control; may vary with indication) or INR of 2-4.5 without signs of hemorrhage
Potential nursing diagnoses of Warfarin Ineffective tissue perfusion (indications); Risk for injury (side effects)

Section 2

Question Answer
Heparin Anticoagulant; Prophylaxis and treatment of various thromboembolic disorders including venous thromboembolism, pulmonary emboli, atrial fibrillation with embolization, acute and chronic consumptive coagulopathies, peripheral arterial thromboembolism; Used in very low doses (10-100 units) to maintain patency of IV catheters (heparin flush)
Heparin actions Potentiates the inhibitory effect of anti-thrombin on factor Xa and thrombin; In low doses, prevents the conversion of pro-thrombin to thrombin by its effects on factor Xa; higher doses neutralize thrombin, preventing the conversion of fibrinogen to fibrin
Heparin therapeutic uses Prevention of thrombus formation; Prevention of extension of existing thrombi (full dose); Used to treat and prevent blood clots in the veins, arteries, or lung; Also used before surgery to reduce the risk of blood clots
Elimination/Excretion of Heparin Removed by the reticulo-endothelial system (lymph nodes, spleen)
Adverse/Side Effects of Heparin Bleeding, heparin-induced thrombocytopenia (HIT) (with or without thrombosis), anemia
Contraindications of Heparin Hypersensitivity; Uncontrolled bleeding; Severe thrombocytopenia; Open wounds (full dose); Avoid use of products containing benzyl alcohol in premature infants
Use Heparin cautiously in Severe liver or kidney disease; retinopathy (hypertensive or diabetic); Untreated hypertension; Ulcer disease; Spinal cord or brain injury; history of congenital or acquired bleeding disorder; malignancy; OB: may be used during pregnancy, yet use with caution during the last trimester and in the immediate post-partum period; Geri: women >60 years of age have increase risk of bleeding
Use of Heparin, exercise extreme caution in Severe uncontrolled hypertension; bacterial endocarditis, bleeding disorders; GI bleeding/ulceration/pathology; hemorrhagic stroke; recent CNS ophthalmologic surgery; active GI bleeding/ulceration; history of thrombocytopenia related to heparin
Drug/Food interactions of Heparin Frequently used concurrently or sequentially with other agents affecting coagulation; The risk of potentially serious interactions is greatest with full anticoagulation; Risk of bleeding may be increase by concurrent use of drugs that affect platelet function, including aspirin, NSAIDs, clopidogrel, dipyridamole, some penicillins, ticlopidine, abciximab, eptifibitide, tirofiban, and dextran; risk of bleeding may be increased by concurrent use of drugs that cause hypo-pro-thrombinemia, including quinidine, cefoperazone, cefotetan, and valproic acid; Concurrent use of thrombolytics increase risk of bleeding; Heparins affect the pro-thrombin time used in assessing the response to warfarin; Digoxin, tetracyclines, nicotine, and antihistamines may decrease anticoagulant effect of heparin; Streptokinase may be folled by relative resistance to heparin; Increase risk of bleeding with arnica, anise, chamomile, clove, dong quai, feverfew (Eurasian plant of the daisy family used to treat headaches), garlic, ginger, and Panax ginseng
Medication administration of Heparin Therapeutic anti-coagulation: IV (neonates and infants < 1 year of age) and Subcut; Prophylaxis of thromboembolism: Subcut; Cardiovascular surgery: IV and Intra-arterial; Line flushing: IV; Total parental nutrition: IV; Arterial line patency: Intra-arterial (neonates); Solution for injection and Pre-mixed solution
Nursing interventions of Heparin Assess for signs of bleeding and hemorrhage (bleeding gums, nosebleed; unusual bruising; black, tarry stools; hematuria; fall in hematocrit or BP; guaiac-positive stools), and notify health care professional is occur; Assess patient for evidence of additional or increased thrombosis; Monitor patient for hypersensitivity reactions (chills, fever, urticarial); Subcut: Observe injection sites for hematomas, ecchymosis, or inflammation; :ab test considerations: Monitor activated partial thromboplastin time (aPTT) and hematocrit prior to and periodically during therapy; Monitor platelet count every 2-3 days throughout therapy. May cause mild thrombocytopenia, which appears on 4th day and resolves despite continued heparin therapy. Heparin-induced thrombocytopenia (HIT), a more severe form, which necessitates discontinuing medication, may develop on 8th day of therapy; may reduce platelet count to as low as 5000/mm^3 and lead to increased resistance to heparin therapy. HIT may progress to development of venous and arterial thrombosis (HITT) and may occur up to several weeks after discontinuation. Patients, who have received a previous course of heparin, may be at higher risk for severe thrombocytopenia for several months after the initial course; Toxicity and overdose: Protamine sulfate is the antidote; Due to short half-life, overdose can often be treated by withdrawing the drug
Heparin antidote Protamine sulfate
High alert of Heparin Fatal hemorrhages have occurred in pediatric patients due to errors in which heparin sodium injection vials were confused with heparin flush vials-carefully examine all heparin sodium injection vials to confirm the correct vial choice prior to administration
Client education of Heparin Advise patient to report any symptoms of unusual bleeding or bruising to health care professional immediately; Instruct patient not to take medications containing aspirin or NSAIDS while on heparin therapy; Caution patient to avoid IM injections and activities leading to injury and to use a soft toothbrush and electric razor during heparin therapy; Advise patient to inform health care professional of medication regimen prior to treatment or surgery; Patients on anti-coagulant therapy should carry an identification card with this information at all times
Evaluation/Desired outcomes of Heparin Prolonged partial thromboplastin time (PTT) of 1.5-2.5 times the control, without signs of hemorrhage; Prevention of deep vein thrombosis and pulmonary emboli; Patency of IV catheters
Potential nursing diagnoses of Heparin Ineffective tissue perfusion (indication); Risk for injury (side effects)