Table 2.
Heparin Nomogram Dosing Adjustments Based on aPTT and Anti-Xa Concentrations.
| Nomograma | aPTT (seconds) or Anti-Xa (U/mL) Result and Bolus/Rate Changeb | ||||||
|---|---|---|---|---|---|---|---|
| DVT/PE | ≤48 or ≤0.20; 80 U/kg bolus and ↑ previous infusion by 4 U/kg/h | 49-67 or 0.21-0.29; 40 U/kg bolus and ↑ previous infusion by 2 U/kg/h | 68-106 or 0.3-0.7; no change | 107-115 or 0.71-0.80 and ↓ infusion by 2 U/kg/h | 116-125 or 0.81-0.99; hold infusion for 1 hour, then ↓ infusion by 3 U/kg/h | > 125 or ≥ 1.0; hold infusion for 2 hours, then ↓ infusion by 4 U/kg/h | NA |
| UA/NSTEMI | ≤48 or ≤0.20; 60 U/kg bolus and ↑ previous infusion by 4 U/kg/h | 49-67 or 0.21-0.29; 30 unit/kg bolus (not to exceed 2000 U) and ↑ previous infusion by 2 U/kg/h | 68-96 or 0.3-0.6; no change | 97-115 or 0.61-0.80; ↓ infusion by 2 U/kg/h | 116-125 or 0.81-0.99; hold infusion for 1 hour, then ↓ infusion by 3 U/kg/h | >125 or ≥1.0; h Hold infusion for 2 hours, then ↓ infusion by 4 U/kg/h | NA |
| Afib/Post-Op | ≤48 or ≤0.20; 60 U/kg bolus and ↑ previous infusion by 3 U/kg/h | 49-67 or 0.21-0.29; 40 unit/kg bolus and ↑ previous infusion by 2 U/kg/h | 68-82 or 0.3-0.45; no change | 83-96 or 0.46-0.60; hold infusion for 1 hour, then ↓ infusion by 1 U/kg/h | 97-106 or 0.61-0.70; hold infusion for 1 hour, then ↓ infusion by 2 U/kg/h | 107-125 or 0.71-0.99; hold infusion for 1 hour, then ↓ infusion by 4 U/kg/h | >125 or ≥1.0; hold infusion for 2 hours, then ↓ infusion by 6 U/kg/h |
| Stroke/EP/VAD/high-risk bleed | ≤48 or ≤0.20; ↑ previous infusion by 2 U/kg/h | 49-58 or 0.21-0.24; ↑ previous infusion by 1 U/kg/h | 59-72 or 0.25-0.35; no change | 73-82 or 0.36-0.45; ↓ infusion by 1 U/kg/h | 83-106 or 0.46-0.69; hold infusion for 1 hour, then ↓ infusion by 2 U/kg/h | >106 or ≥0.70; stop infusion and call physician | N/A |
Abbreviations: Afib, atrial fibrillation; ; aPTT, activated partial thromboplastin time; DVT/PE, deep vein thrombosis/pulmonary embolism; EP, electrophysiology; Post-Op, post-operative; UA/NSTEMI, unstable angina/non-ST-segment elevation myocardial infarction; VAD, ventricular assist device.
aDVT/PE, UA/NSTEMI, and Afib/Post-Op nomograms may be ordered with or without a bolus. No bolus nomograms omit the use of an initial bolus and additional boluses based on a subtherapeutic aPTT or anti-Xa concentration. Information shown here is for bolus dosing with these nomograms. Bolus dosing of intravenous unfractionated heparin for DVT/PE and Afib/Post-Op nomogram not to exceed 10 000 U; UA/NSTEMI nomogram not to exceed 4000 U (except where otherwise noted). Note that stroke/EP/VAD/high-risk bleed nomogram does not include a bolus at initiation or with adjustments based on aPTT or anti-Xa concentration.
bRepeat STAT aPTT or anti-Xa 6 hours after rate change; goal is 2 consecutive therapeutic results at which point laboratory parameter is checked daily.