3 Learning ObjectivesDescribe the influence of anticoagulants on blood clottingDevelop a teaching plan for patients taking anticoagulants on a long-term basisIdentify drugs that act in the formation, repair, or function of red blood cellsIdentify at least three adverse reactions associated with hematologic products.
4 Anticoagulants Two Categories Coumarin and indandione derivatives – Limit the formation of blood coagulation factors II, VII, IX, and X in the liver by interfering with vitamin KHeparin sodium– Increases the action of antithrombin III (heparin cofactor) on several other coagulation factors to slow new clot developmentHeparin and coumarin and indandione derivatives interfere with the blood clotting chain at multiple sites. Neither of these categories of medication dissolves existing clots.Blood clots that are “fixed” in the body are called “thrombi.” Blood clots moving throughout the circulation are called “emboli.” All emboli eventually end up traveling to the lungs, heart, and brain, because that is the normal route of circulation and where major damage can occur.Low-molecular-weight heparin is a special formulation used in special circumstances, such as prevention of deep vein thrombosis after surgery.
5 Anticoagulants (cont.) Action and UsesPrevent new thrombus formationStop existing thrombi from growing in sizeProphylactic: postsurgery involving the heart or circulatory systemPatients with heart valve disease, some dysrhythmias, and receiving hemodialysisPatients on prolonged bed rest or with a history of thrombus formationThere are many indications for anticoagulant therapy. When a clot (thrombus) lodges in the circulatory system, blood flow is diminished or cut off to the area. This results in tissue and organ impairment and/or death.It is beneficial to “thin the blood” in patients with heart valve disease or some dysrhythmias to facilitate circulation in these impaired areas and prevent blood from pooling and clotting.Patients on hemodialysis have an internal access device that is placed in an area that has a high degree of circulation. As this is an invasive technique, and hemodialysis is essential to maintain the patient’s life, anticoagulants are used to keep the device open.Heparin is used for acute therapy because it is given IV or SQ. Heparin is also used if the patient is pregnant. Warfarin (Coumadin) is used for long-term therapy.
6 Anticoagulants (cont.) Adverse ReactionsWarfarin (Coumadin): alopecia, rash, urticaria, cramping, diarrhea, intestinal obstruction, nausea, paralytic ileus, vomiting, excessive uterine bleeding, hemorrhage, leukopenia, feverHeparin sodium: hypertension, headache, hematoma, conjunctivitis, tearing of eyes, rhinitis, hemorrhage, thrombocytopenia, dyspnea, chills, fevers, alopecia, persistent or prolonged erection, hypersensitivityThere are many adverse reactions to anticoagulant therapy. Patients requiring these drugs are typically compromised. It is important to closely assess patients for leukopenia and thrombocytopenia, which would put them at additional risk.Early signs of overdosage or internal bleeding include bleeding from gums while brushing teeth, excessive bleeding or oozing from cuts, unexplained bruising or nosebleeds, and unusually heavy or unexpected menses in women.
7 Anticoagulants (cont.) Drug InteractionsNursing Implications and Patient TeachingCalculation procedure of heparin criticalMonitoring blood valuesCoumadin = prothrombin time (PT); therapeutic is 1.5 to 2.5 × normal or an INR of 2.0 to 3.0Heparin = activated partial thromboplastin time (aPPT); therapeutic is 2.5 to 3 × the control valueMany drugs alter the effect of anticoagulants. Coumarin and indandione derivatives increase the effect of heparin as do alcohol, aspirin, NSAIDs, and dextran.Antihistamines, digitalis, nicotine, and tetracycline decrease the anticoagulant effect of heparin.ASA, corticotropin, ethacrynic acid, glucocorticoids, and NSAIDs increase the risk of GI bleeding with heparin.Adrenocorticosteroids, antacids, antihistamines, barbiturates, oral contraceptives, estrogens, griseofulvin, haloperidol, meprobamate, primidone, rifampin, thiazide diuretics, and vitamin K decrease the action of Coumadin.Oral hypoglycemics taken with anticoagulants may increase the effect of either the hypoglycemic or anticoagulant.Close monitoring and evaluation by the healthcare provider are essential when patients are taking these medications.
8 Anticoagulants (cont.) Nursing ProcessAssessmentDiagnosis– Planning– Implementation– EvaluationPatient and Family TeachingOngoing assessment and evaluation by the nurse is critical. Patients can experience life-threatening adverse reactions within a short time.Let’s discuss the patient and family teaching that should occur when patients are put on these drugs. What points should be emphasized to the patient?What types of concerns should the patient report to the healthcare provider?
9 Protamine Sulfate Action Uses Adverse Reactions Strong, alkaline protein that neutralizes effects of heparinResults immediate, last 2 hours or moreUsesTreatment of heparin overdosageAfter surgical procedure where heparin was usedAdverse ReactionsWhen a patient requires use of the heart-lung machine (extracorporeal circulation), large doses of heparin are used. Protamine sulfate is used to counteract the heparin when the machine is discontinued.Adverse reactions to this medication include bradycardia, dyspnea, lassitude, hypotension, transitory flushing, and feeling of warmth.An overdosage of this medication produces anticoagulant effects.Protamine sulfate is only given by a physician, IV, over 1 to 3 minutes. Typical dosage is 50 mg or less over a 10-minute period.What teaching would the LVN/LPN offer the patient and family?
10 Thrombolytic Agents Action Uses Convert plasminogen to the enzyme plasmin, which breaks down fibrin clots, fibrinogen, and other plasma proteinsUsesAcute myocardial infarctionsAcute pulmonary emboliAcute ischemic strokeAcute arterial occlusionThere is a narrow window of time for these drugs to be successful in dissolving thrombi during emergent events. Therefore, prompt initiation of the emergency system is essential.Bleeding is the most common adverse reaction, along with dysrhythmias, hypotension, polyneuropathy, cholesterol embolism, pulmonary embolism, and drug hypersensitivity. If administered with other anticoagulants in the patient’s system, there is increased risk of bleeding.What should the LPN/LVN consider when assisting with the administration of these drugs?What patient and family teaching should occur?
11 Antiplatelet Agents Action Uses Inhibit platelet aggregation (clumping)Reduce thrombus formationUsesSalicylic acid (aspirin)Reduces incidence of myocardial-infarction-related deaths in men over 50Drug of choice in ischemic strokePlatelet aggregation or clumping is essential for a blood clot (thrombus) to develop.Aspirin continues to be one of the leading antiplatelet agents.Many drugs, especially OTC preparations, contain aspirin compounds; patients should be made aware that these will increase the risk of bleeding.
12 Antiplatelet Agents (cont.) Uses (cont.)Dipyridamole (Persantine), ticlopidine (Ticlid), clopidogrel (Plavix)Myocardial prophylaxis for menAdjunctive therapy with thrombolytics to prevent an infarction or strokeAbciximab (ReoPro), anagrelide (Agrylin)During cardiac catheterization and cardiac proceduresBleeding is the most common adverse reaction to antiplatelet agents. Other adverse reactions include diarrhea, nausea, dyspepsia, rash, GI pain, neutropenia, purpura, vomiting, flatulence, pruritus, dizziness, and anorexia.Antiplatelets have variable reactions when given with antacids, cimetidine, digoxin, and theophylline.During an emergent situation, close patient monitoring is crucial.What patient and family teaching should occur?