Heparin
A to Z Drug Facts
(HEP-uh-rin) |
Heparin Sodium, Hep-Lock, Hep-Lock U/P, Hepalean, Hepalean-Lok, Heparin Leo, Heparin Lock Flush |
Class: Anticoagulant |
Action Inhibits reactions that lead to clotting.
Indications Prophylaxis and treatment of venous thrombosis and its extensions, pulmonary embolism (PE), peripheral arterial embolism, and atrial fibrillation with embolization; diagnosis and treatment of acute and chronic consumption coagulopathies (DIC); prevention of postoperative deep venous thrombosis(DVT), and PE. Unlabeled use (s): Prophylaxis of left ventricular thrombi and cerebrovascular accidents post-MI; treatment of myocardial ischemia; prevention of cerebral thrombosis in evolving strokes; adjunctive treatment of coronary occlusion with acute MI.
Contraindications Severe thrombocytopenia; uncontrolled bleeding (except due to DIC); patients in whom suitable blood coagulation tests cannot be performed.
Route/Dosage
ADULTS: SC 10,000 to 20,000 U as initial dose followed by 8000 to 20,000 U q 8 to 12 hr. Intermittent IV 10,000 U as initial dose followed by 5000 to 10,000 U q 4 to 6 hr. IV infusion 20,000 to 40,000 U/day. CHILDREN: Intermittent IV 50 U/kg as initial dose followed by 100 U/kg q 4 hr. IV infusion 50 U/kg as initial dose followed by 20,000 U/m2/24 hr.
Low-dose Prophylaxis
SC 5000 U 2 hr before surgery and q 8 to 12 hr thereafter for 7 days or until patient is fully ambulatory, whichever is longer.
Surgery of Heart and Blood Vessels
ADULTS: 300 to 400 U/kg.
Blood Transfusion
Add 400 to 600 U/100 ml of whole blood.
Clearing Intermittent Infusion Sets
10 to 100 U/ml.
Laboratory Samples
Add 70 to 150 U/10 to 20 ml of whole blood.
Interactions
Dipyridamole, hydroxychloroquine, NSAIDs, salicylates: May cause increased risk of bleeding. INCOMPAT IBILITIES: Heparin is acidic and incompatible with many drugs.
Lab Test Interferences Aminotransferase (AST and ALT): Drug causes increased concentrations.
Adverse Reactions
DERM: Necrosis; transient alopecia; urticaria. HEMA: Hemorrhage; thrombocytopenia. OTHER: Hypersensitivity (chills, fever, urticaria, asthma, rhinitis, lacrimation, headache, nausea, vomiting, shock); anaphylactoid reactions; allergic vasospastic reactions, including painful ischemia, cyanotic limbs; osteoporosis; priapism; rebound hyperlipidemia on discontinuation.
Precautions
Pregnancy: Category C. Lactation: Not excreted in breast milk. Elderly or debilitated patients: Higher incidence of bleeding in women > 60 yr. Benzyl alcohol sensitivity: Benzyl alcohol, used as preservative in some products, is associated with a fatal gasping syndrome in premature infants. IM use: Avoid IM use because of local irritation, erythema, pain, hematoma, or ulceration. Hypersensitivity: Generalized hypersensitivity can occur. Reactions range from mild to severe. Hemorrhage: Hemorrhage can occur at virtually any site. Use heparin with extreme caution in patients at increased risk of hemorrhage. Hyperlipidemia: Heparin administration may cause hyperlipidemia in patients with dysbetalipoproteinemia (type III).
PATIENT CARE CONSIDERATIONS |
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Administration/Storage
- Heparin is strongly acidic and is incompatible with many drugs. Avoid mixing any drug with heparin unless specifically advised by health care provider.
- Avoid IM administration.
- SC administration should be deep, preferably into fatty layers of abdomen. Use small-gauge needle to minimize tissue trauma. Bunch up tissue without pinching and insert needle at 90° angle to skin. Inject slowly.
- Do not aspirate patient to check entry into blood vessel. Apply gentle pressure to puncture site for about 1 min; do not massage. Rotate injection sites frequently and keep record.
- IV administration may be given undiluted over 1 min.
- For IV infusion, dilute prescribed amount in 0.9% Sodium Chloride for Injection, D5W, or Ringer's Injection solution. Use infusion pump to ensure accuracy.
- For heparin locks, inject diluted heparin solution of 10 to 100 U (0.5 to 1 ml).
- To prevent incompatibility of heparin with medication, flush heparin lock set with Sterile Water for Injection or 0.9% Sodium Chloride for Injection before and after medication is administered.
- Store at room temperature. Protect from freezing.
- Inspect all preparations for particulate matter prior to administration. Also inspect for discoloration; note that slight discoloration does not alter potency.
Assessment/Interventions
- Obtain patient history, including drug history and any known allergies.
- Monitor vital signs. Report fever, drop in blood pressure, rapid pulse, and other signs and symptoms of hemorrhage to health care provider.
- Perform baseline blood coagulation tests, hemoglobin, hematocrit, RBC, and platelet counts before therapy is initiated.
- Monitor I & O during early therapy. Heparin may have diuretic effect beginning 36 to 48 hr after initial dose and last 36 to 48 hr after termination of therapy.
- Assess for signs of bleeding and hemorrhage. Venipuncture sites may require pressure to prevent bleeding and hematoma formation.
- Assess for evidence of additional or increased thrombosis.
- Observe injection sites for hematomas, ecchymosis, and inflammation.
- Activated partial thromboplastin time (aPTT) and activated coagulation time (ACT) are coagulation tests commonly used to monitor heparin therapy. Dosage is adjusted to keep aPTT between 1½ and 2 times normal control level. ACT is ideally 2 to 3 times control value in sec.
- During dosage adjustment periods, draw blood for coagulation tests ½ hr before each scheduled SC or intermittent IV dose.
- Follow agency protocol for heparin administration, particularly when piggybacking heparin with other drugs.
- Inform all personnel caring for patient that patient is receiving anticoagulant therapy.
- Avoid IM injections of other medication because hematomas may develop.
- In patients requiring long-term anticoagulation therapy, institute oral anticoagulation therapy. To ensure continuous anticoagulation, continue full heparin therapy for several days after PT has reached therapeutic range. Heparin can then be stopped without tapering.
- Monitor patient frequently for signs of infiltration, to see that tubing is not kinked, to ensure that tubing is properly positioned in pump, and to check all connections for leakage.
- Construct flow chart indicating dates, coagulation time determinations, Hct, leukocyte and platelet counts, heparin doses, and urine and stool tests for occult blood.
- Make accurate observations of clinical response.
OVERDOSAGE: SIGNS & SYMPTOMS |
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Bleeding, nosebleeds, hematuria, tarry stools, easy bruising, or petechiae |
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Patient/Family Education
- Caution patient to avoid IM injections.
- Advise patient to avoid activities that carry risk of injury.
- Instruct patient to use soft toothbrush and electric razor.
- Caution patient to avoid aspirin and aspirin-containing medications.
- Advise patient to report unusual bruising or bleeding (nosebleeds, bleeding gums) or tarry stools to health care provider immediately.
- Instruct patient to inform health care providers and dentists of use of this medication before treatment or surgery.
- Inform patient of potential for hair loss. Explain that this effect may occur several months after heparin therapy is started. Reassure patient that if alopecia occurs, hair growth will return after drug has been discontinued.
- Advise patient to carry identification card or to wear a medication identification bracelet (ie, Medi-Alert) that indicates heparin therapy.
- Inform female patients that menstruation may be somewhat increased and prolonged. Usually this effect is not a contraindication to therapy if bleeding is not excessive and there is no underlying pathologic condition.
- Advise patient that smoking and alcohol may alter response to heparin, and therefore, are not advised.
- Inform patient that abrupt withdrawal of heparin may precipitate increased coagulability.
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Copyright © 2003 Facts and Comparisons
David S. Tatro
A to Z Drug Facts