Unfractionated heparin
(Redirected from Unfractionated Heparin)
General
- Type: Anticoagulant
- Dosage Forms: IV, SC
- Common Trade Names: Heparin
Adult Dosing
Thromboembolism
- Bolus: 80 units/kg IV x 1 (MAX: 5,000 units)
- Then drip: 18 units/kg/h IV (MAX: 1,000 units/h)
- Adjust dose to target aPTT levels based on nomogram
Acute Coronary Syndrome
- Bolus: 50 units/kg IV x 1 (MAX: 5,000 units)
- Then drip: 12 units/kg/h IV (MAX: 1,000 units/h)
- Adjust dose to target aPTT levels based on nomogram
Pediatric Dosing
- IV infusion
- Initial loading dose 75 units/kg given over 10 minutes
- Initial maintenance dose 20 units/kg/hour and adjest per local policy
Special Populations
- Pregnancy Rating: C
- Lactation risk: Infant risk minimal
- Renal Dosing
- No adjustment
- Hepatic Dosing
- No adjustment
Contraindications
- Allergy to class/drug
- 33% of patients develop some form of bleeding complication; 2-6% develop major bleeding
- HIT (Heparin-Induced Thrombocytopenia)
Risk Factors for Major Bleeding Complication
- Recent surgery or trauma
- Renal failure
- Alcoholism
- Malignancy
- Liver failure
- Concurrent use of warfarin, fibrinolytics, steroids, or antiplatelet drugs
Adverse Reactions
Serious
- Major bleeding
- Thrombocytopenia
Common
- Injection site reaction[1]
- Hyperkalemia
- Alopecia
- Osteoporosis
Pharmacology
- Half-life: 1.5 hrs
- Metabolism: Hepatic
- Excretion: Urine
- Mechanism of Action:
- Binds to and activates antithrombin which in turns inactivates factor Xa and thrombin
- Anticoagulation effect lasts up to 3hr after stopping infusion
- Must give IV (not subq) for acute thromboembolic disease
- Unpredictable anticoagulation effect
- Must monitor with PTT; therapeutic range is 1.5-2.5x normal value
Indications by Condition
The following table is automatically generated from disease/condition pages across WikEM.
| Indication | Dose | Context | Route | Population |
|---|---|---|---|---|
| Acute arterial ischemia | 80 units/kg bolus, then 18 units/kg/hr infusion | Anticoagulation to prevent clot propagation | IV | Adult |
| Non-ST-elevation myocardial infarction | 60-70 units/kg bolus (max 5000), then 12-15 units/kg/hr (max 1000/hr) | Antithrombotic; consider if PCI/CABG within 24hr or renal failure | IV | Adult |
| Pulmonary embolism | 80 units/kg IV bolus, then 18 units/kg/hr continuous infusion | Anticoagulation (preferred if rapid reversal needed) | IV drip | Adult |
| ST-segment elevation myocardial infarction | 60 units/kg IV bolus (max 4000 U), then 12 units/kg/hr (max 1000 U/hr); titrate to PTT 1.5-2.5x control | Anticoagulation (required with thrombolytics/PCI) | IV drip | Adult |
| Unstable angina | 60 units/kg IV bolus (max 4000 units), then 12 units/kg/hr (max 1000 units/hr) | Antithrombotic | IV | Adult |
See Also
References
- ↑ Warnock LB, Huang D. Heparin. [Updated 2022 Jul 12]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2022 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK538247/