Table 1 Unfractionated heparin nomogram
Anti-Xa level | Dosing change | Repeat anti-Xa level |
|---|---|---|
< 0.2 units per mL | 80 unit per kilogram bolus (maximum 10,000 units) followed by an increase in the rate of the infusion by 4 units per kilogram per hour | Repeat anti-Xa level 6 h later |
0.21–0.29 units per mL | 40 unit per kilogram bolus (maximum 10,000 units) followed by an increase in the rate of the infusion by 2 units per kilogram per hour | Repeat anti-Xa level 6 h later |
0.30–0.70 units per mL (therapeutic) | No changes necessary | Repeat anti-Xa level every 6 h until two consecutive therapeutic anti-Xa levels are achieved then check anti-Xa level daily |
0.71–0.80 units per mL | Decrease the rate of the infusion by 2 units per kilogram per hour | Repeat anti-Xa level 6 h later |
0.81–1.00 units per mL | Stop the infusion for 1 h then restart after decreasing the rate of infusion by 3 units per kilogram per hour | Repeat anti-Xa level 2 h later |
> 1.00 units per mL | Stop the infusion for 2 h then restart after decreasing the rate of infusion by 4 units per kilogram per hour | Repeat anti-Xa level 2 h later |