1. Initial Bolus Dosage
|
80 units/kg actual body weight. Maximum bolus dose 10,000 units |
|
Check baseline APTT before starting heparin |
|
No bolus for neuro patients unless requested by Intensivist |
2. Infusion Dosage
|
Mix 5000 units heparin in 50 ml NS (concentration 100 units/ml) |
|
Start at 18 units/kg/hr |
|
Check APTT 6 hrs after starting infusion and adjust rate as per nomogram |
|
After each dose change, wait 6 hours before taking blood for the next PTT test |
3. Monitoring
|
Obtain CBC daily and PTT daily following dose changes. |
|
Obtain PTT 6 hours after initiation of Heparin and after any subsequent changes until therapeutic X 2, then every 6 AM. |
|
Monitor Platelets and consider discontinuing heparin if platelets decrease by > 30% from baseline and evaluate for Heparin Induced Thrombocytopenia (HIT). |
|
Monitor for bleeding. |
4. Nomogram for adjusting Heparin Drip Rates
4.1. STANDARD BLEEDING RISK PATIENTS: (Goal PTT 79-118 seconds)
|
PTT (seconds) |
Rebolus or Hold |
Rate Adjustment |
Recheck PTT |
|
≤ 60 |
Bolus: 80 units/ kg |
↑4 units/kg/hr |
6 hrs |
|
61 - 78 |
Bolus: 40 units/ kg |
↑2 units/kg/hr |
6 hrs |
|
GOAL 79 - 118 |
NONE |
NONE |
In AM |
|
119 - 135 |
NONE |
↓ 2 units/kg/hr |
6 hrs |
|
≥ 136 |
HOLD 60 minutes |
↓ 3 units/kg/hr |
6 hrs |
4.2. HIGHER BLEEDING RISK PATIENTS: (Goal PTT 70-103 seconds)
|
PTT (seconds) |
Rebolus or Hold |
Rate Adjustment |
Recheck PTT |
|
≤ 59 |
Bolus: 2000 units |
↑2 units/kg/hr |
6 hrs |
|
60-69 |
NONE |
↑2 units/kg/hr |
6 hrs |
|
GOAL 70-103 |
NON |
NONE |
In AM |
|
104-116 |
NONE |
↓ 1 units/kg/hr |
6 hrs |
|
≥ 117 |
HOLD 60 minutes |
↓ 3 units/kg/hr |
6 hrs |
4.3. POST-OP AND TRAUMA PATIENTS: (Goal PTT 60-79 seconds)
|
PTT |
Rebolus or Hold |
Rate Adjustment |
Recheck PTT |
|
≤ 59 |
Bolus: 2000 units |
↑1 units/kg/hr |
6 hrs |
|
GOAL 60-79 |
NONE |
NONE |
In AM |
|
80-90 |
NONE |
↓ 0.5 units/kg/hr |
6 hrs |
|
91-100 |
NONE |
↓ 1 units/kg/hr |
6 hrs |
|
101-109 |
HOLD 60 minutes |
↓ 2 units/kg/hr |
6 hrs |
|
≥ 110 |
HOLD 60 minutes |
↓ 3 units/kg/hr |
6 hrs |
Further readings:
1. Lechner, D. L. (1997). A standardized weight-based heparin protocol. Nursing Management, 28(4), 29.
2. Garcia, D. A., Baglin, T. P., Weitz, J. I., & Samama, M. M. (2012). Parenteral anticoagulants: antithrombotic therapy and prevention of thrombosis: American College of Chest Physicians evidence-based clinical practice guidelines. Chest, 141(2), e24S-e43S.
3. Cruickshank, M. K., Levine, M. N., Hirsh, J., Roberts, R., & Siguenza, M. (1991). A standard heparin nomogram for the management of heparin therapy. Archives of internal medicine, 151(2), 333-337.
4. Gunnarsson, P. S., Sawyer, W. T., Montague, D., Williams, M. L., Dupuis, R. E., & Caiola, S. M. (1995). Appropriate use of heparin: empiric vs nomogram-based dosing. Archives of internal medicine, 155(5), 526-532.
