| Initial intravenous heparin bolus: 5000 units. |
| Continuous intravenous heparin infusion: commence at 42 mL/hour of 20,000 units (1680 units/hour) in 500 mL of two-thirds dextrose and one-third saline (a 24-hour heparin dose of 40,320 units), except in the following patients, in whom heparin infusion will be commenced at a rate of 31 mL/hour (1240 units/hour) (ie, a 24-hour dose of 29,760 units). |
| Patients who have undergone surgery within the previous two weeks. |
| Patients with a previous history of peptic ulcer disease, gastrointestinal or genitourinary bleeding. |
| Patients with (thrombotic) stroke within the previous two weeks. |
| Patients with a platelet count <150,000/microL. |
| Patients with miscellaneous reasons for a high risk of bleeding (eg, hepatic failure, renal failure, or vitamin K deficiency). |
| Heparin dose adjusted using the aPTT. The aPTT is performed in all patients as outlined below: |
| 4 to 6 hours after commencing heparin; the heparin dose is then adjusted according to the nomogram shown in Heparin Protocol-II until the aPTT is within the therapeutic range. |
| Thereafter, the aPTT will be performed once daily. If the value is outside the therapeutic range, the heparin dose is then adjusted according to the nomogram shown in Heparin Protocol-II until the aPTT is within the therapeutic range. |
