Table 1 Key points about monitoring of unfractionated heparin, low molecular weight heparins and fondaparinux[78, 162]
| Â | Indications | Posology and route of administration | Delay for blood sampling | Anti-Xa activity (IU/mL) | aPTT |
|---|---|---|---|---|---|
Unfractionated heparin | |||||
Sodium heparin | -Prevention of clotting during hemodialysis | Bolus of 1,000 - 5,000 IU followed by 1,000 - 2,000 IU per hour | The sampling is performed whatever the time in case of IV perfusion, preferably 4 to 6h after each dosage variation. | 0.3 to 0.7 | 1.5 to 3.0 – 8.0 the upper limit of normal depending on the reagent |
-Cardiopulmonary bypass | 300 units/kg intravenously, adjusted thereafter to maintain the activated clotting time (ACT) in the range 300-400 seconds | Â | |||
Calcium heparin | -Prevention of clotting during hemodialysis | Loading dose of 1,000-5,000 units followed by 1,000-2,000 units/hour | Part-time between 2 injections (6h after injection for a 2 injections/day) or 4h after injection for a 3 injections/day | ||
-Cardiopulmonary bypass | 300 units/kg intravenously, adjusted thereafter to maintain the activated clotting time (ACT) in the range 300-400 seconds | Â | |||
Low molecular weight heparins: 2 injections per day†| |||||
Enoxaparin | -DVT associated with or not PE | 100 IU/kg/12 hours or 1mg/kg/12 hours - subcutaneous | 3 to 4 hours after the injection | 1.2 (+- 0.17) IU/mL | Slightly prolonged |
-Acute coronary syndrome | |||||
Dalteparin | -Constituted DVT | 100 to 120 IU/kg/12 hours – subcutaneous | 0.6 (+- 0.25) IU/mL (overdose threshold 1.0 IU/mL) | ||
Nadroparin | -Unstable angina -Myocardial infarction without Q wave | 85 IU/kg/12 hours | 1.0 (+- 0.2) IU/mL | ||
Low molecular weight heparins: 1 injection per day†| |||||
Tinzaparin | -Constituted DVT | 175 IU/kg/24h | 4 to 6 hours after the injection | 0.87 (+- 0.15) IU/mL (overdose threshold: <1.5 IU/mL) | Prolonged |
-PE | |||||
Nadroparin | -Constituted DVT | 171 IU/kg/24h | Â | 1.34 (+- 0.15) IU/mL (overdose threshold: <1.8 IU/mL) | Slightly prolonged |
Fondaparinux | Â | ||||
Fondaparinux | -Constituted DVT | In patients with DVT or PE, dosing was determined by patient weight, with either 5 mg (weight <50 kg), 7.5 mg (weight 50–100 kg), or 10 mg (weight >100 kg) administered/24hours. | 2 to 3 hours after administration | The mean peak steady state concentrations for were 1.20–1.26 mg/L | Not prolonged |
-PE | |||||
|  | -Acute coronary syndrome | 2.5 mg/24 hours | 2 to 3 hours after administration | Healthy males receiving a single 2.5 mg dose of fondaparinux had an average peak steady state (3 hours) concentration of 0.39–0.5 mg/L | |