Heparin contraindications

Discuss the uses, general drug actions, adverse reactions, contraindications, precautions, and interactions of warfarin, heparin preparations, and the thrombolytic drugs. 

The LMWHs are contraindicated in patients witii a hypersensitivity to the drug, heparin, or pork products and inpatients with active bleeding or thrombocytopenia... 

Heparin-induced thrombocytopenia (HIT) is a very serious adverse effect associated with UFH use. Platelet counts should be monitored every 2 to 3 days dining the course of UFH therapy.5 HIT should be suspected if the platelet count drops by more than 50% from baseline or to below 120,000. In patients with contraindications to anticoagulation therapy, UFH should not be administered (Table 7-7). 

Deep vein thrombosis prophylaxis is recommended for septic patients. Low-dose unfractionated heparin or low-molecular-weight heparin may be utilized. Graduated compression stockings or an intermittent compression device is recommended for patients with a contraindication to heparin products (thrombocytopenia, severe coagulopathy, active bleeding, or recent intracerebral hemorrhage).24... 

Contraindications to heparin therapy include hypersensitivity to the drug, active bleeding, hemophilia, severe liver disease with elevated prothrombin time (PT), severe thrombocytopenia, malignant hypertension, and inability to meticulously supervise and monitor treatment. 

Heparin Heparin is contraindicated in patients with HIT. If argatroban is initiated after cessation of heparin therapy, allow sufficient time for heparin s effect on the aPTT to decrease prior to argatroban therapy. 

Epoprostenol is the natural occurring prostacyclin which is formed in vascular endothelial cells. It increases cyclic AMP in the thrombocyte and is a strong platelet aggregation inhibitor. It is used to prevent thrombotic complications during hemodialysis when heparin is contraindicated. As its duration of action is no longer than 30 minutes it has to be given as an intravenous infusion. 

Contraindications Evidence of active intravascular clotting process, disseminated intravascular coagulation without concurrent heparin therapy, hematuria of upper urinary tract origin (unless benefit outweighs risk) ... 

Contraindications Active major bleeding concurrent heparin therapy hypersensitivity to dalteparin, heparin, or pork products thrombocytopenia associated with positive in vitro test for antiplatelet antibody... 

Contraindications Acfive major bleeding concurrenf heparin fherapy hypersensifiv-ify fo heparin, sulfifes, benzyl alcohol, or pork producfs fhrombocyfopenia associ-afed wifh posifive in vifro fesf for anfiplafelef anfibody... 

Drug interactions Concurrent administration of ReoPro with oral anticoagulants is contraindicated. Limited experience with the concurrent use of ReoPro and low molecular weight dextran during a PTCA procedure has also shown an increased risk of a major bleeding episode. Concurrent administration of ReoPro and heparin may also increase the risk of bleeding, but ReoPro is intended for use with aspirin and heparin and has only been studied in that setting. ReoPro has... 

Prophylactic enoxaparin is given subcutaneously in a dosage of 30 mg twice daily or 40 mg once daily. Full-dose enoxaparin therapy is 1 mg/kg subcutaneously every 12 hours. This corresponds to a therapeutic anti-factor Xa level of 0.5—1 unit/mL. Selected patients may be treated with enoxaparin 1.5 mg/kg once a day, with a target anti-Xa level of 1.5 units/mL. The prophylactic dose of dalteparin is 5000 units subcutaneously once a day therapeutic dosing is 200 units/kg once a day for venous disease or 120 units/kg every 12 hours for acute coronary syndrome. The use of LMW heparins is discouraged or contraindicated in patients with renal insufficiency or body weight greater than 150 kg. 

The following patient categories were excluded from the study patients with ostial and bifurcation lesions, left ventricular ejection fraction <30%, known hypersensitivity or contraindication to aspirin or stainless steel, or a sensitivity to contrast dye, allergy to heparin or ticlopidine,... 

Adverse effects. When bleeding is induced by heparin, the heparin action can be instantly reversed by protamine. Against fractionated heparins and fondaparinux, protamine is less or not effective. Heparin-induced thrombocytopenia type II (HIT II) is a dangerous complication. It results from formation of antibodies that precipitate with bound heparin on platelets. The platelets aggregate and give rise to vascular occlusions. Because of the thrombocytopenia, hemorrhages may occur. Fondaparinux is also contraindicated in HIT II. 

Fibrinogen Doses of 2-4 g (i.v.) at six to eight-hour intervals are recommended. Where haemorrhaging occurs, simultaneous administration of even small amounts of heparin is strongly contraindicated, particularly as the patient s heparin sensitivity may be highly elevated in this condition as well as after the administration of AT III. The use of heparin in such a situation thus involves very high risks, (s. tab. 19.2)... 

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