Heparin
Drug class
Anticoagulant
Therapeutic actions
Heparin inactivates factor XA, therefore inhibiting thrombus and clot formation by blocking the conversion of prothrombin to thrombin and fibrinogen to fibrin, the final steps in the clotting process. Heparin also inhibits the activation of factor XIII, thrombin-induced activation of factors V and VIII
Indications
Prevention and treatment of venous thrombosis and pulmonary embolism
Treatment of atrial fibrillation with embolization
Diagnosis and treatment of DIC
Prevention of clotting in blood samples and heparin lock sets and during dialysis procedures
Unlabeled uses: Adjunct in therapy of coronary occlusion with acute MI, prevention of left ventricular thrombi and CVA post-MI, prevention of cerebral thrombosis in the evolving stroke
Contraindications and cautions
Contraindicated with hypersensitivity to heparin; severe thrombocytopenia; uncontrolled bleeding; any patient who cannot be monitored regularly with blood coagulation tests; labor and immediate postpartum period; women older than 60 yr are at high risk for hemorrhaging.
Use cautiously with pregnancy; dysbetalipoproteinemia; recent surgery or injury
Available forms
Injection—1,000, 2,000, 2,500, 5,000, 7,500, 10,000, 12,500, 20,000, 40,000 units/mL; also single-dose and unit-dose forms. Lock flush solution—10, 100 units/mL
Interactions
Increased bleeding tendencies with oral anticoagulants, salicylates, penicillins, cephalosporins; low-moleculer-weight heparins
Decreased anticoagulation effects if taken concurrently with nitroglycerin
Adverse effects
Dermatologic: Loss of hair
Hematologic: Hemorrhage; bruising; thrombocytopenia; elevated AST, ALT levels, hyperkalemia
Hypersensitivity: Chills, fever, urticaria, asthma
Other: Osteoporosis, suppression of renal function
Nursing considerations
Always check compatabilities with other IV solutions
Use heparin lock needle to avoid repeated injections
Give deep subcutaneous injections; do not give heparin by IM injection
Do not give IM injections to patients on heparin therapy (heparin predisposes to hematoma formation
WARNING: Apply pressure to all injection sites after needle is withdrawn; inspect injection sites for signs of hematoma; do not massage injection sites
Mix well when adding heparin to IV infusion
Do not add heparin to infusion lines of other drugs, and do not piggyback other drugs into heparin line. If this must be done, ensure drug compatibility
Check for signs of bleeding; monitor blood tests
Alert all health care providers of heparin use
WARNING: Have protamine sulfate (heparin antidote) readily available in case of overdose; each mg neutralizes 100 units of heparin
WARNING: For treatment of overdose, give protamine sulfate (1% solution). Each mg of protamine neutralizes 100 USP heparin units. Give very slowly IV over 10 min, not to exceed 50 mg. Establish dose based on blood coagulation studies