Difference between revisions of "Unfractionated heparin"

(Created page with "==Common Indications== DVT, PE, AFIB, ACS ==Bleeding Risk Factors== A. Surgery, trauma, or stroke within the previous 14 days. B. History of peptic ulcer disease, GI ble...")
 
(Adult Dosing)
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==Common Indications==
+
==General==
 +
*Type: Anticoagulant
 +
*Dosage Forms: IV, SC
 +
*Common Trade Names: Heparin
  
 +
==Adult Dosing==
 +
*See [https://depts.washington.edu/anticoag/home/content/heparin-infusion-guidelines University of Washington pharmacy heparin infusion guidelines]
 +
===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
  
DVT, PE, AFIB, ACS
+
==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==
 +
*[[Drug Ratings in Pregnancy|Pregnancy Rating]]: C
 +
*[[Lactation risk categories|Lactation risk]]: Infant risk minimal
 +
*Renal Dosing
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**No adjustment
 +
*Hepatic Dosing
 +
**No adjustment
  
==Bleeding Risk Factors==
+
==Contraindications==
 +
*Allergy to class/drug
 +
*33% of patients develop some form of bleeding complication; 2-6% develop major bleeding
 +
*Heparin-Induced Thrombocytopenia
 +
*See [[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
  
A. Surgery, trauma, or stroke within the previous 14 days.
+
==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
  
B. History of peptic ulcer disease, GI bleeding or GU bleeding.
+
==See Also==
 +
*[[Unfractionated heparin reversal]]
 +
*[[Coagulopathy (main)]]
 +
*[[Low molecular weight heparin]]
  
C. Platelet count less than 150K
+
==References==
 +
<references/>
  
D. Age > 70 yrs.
+
[[Category:Pharmacology]]
 
 
E. Hepatic failure, uremia, bleeding diathesis, brain metastases.
 
 
 
 
 
 
*Draw extra blue top prior to starting if concerned about a hypercoaguable state (heparin will interfere with assays)
 
 
 
 
 
 
==Treatment ==
 
 
 
 
 
A. Bolus - 150 u/kg for PE, and 80-100 u/kg for all other conditions.
 
 
 
B. Infuse - 15-25 u/kg/hr (high risk --> 15-18 u/kg/hr; low risk --> 22-25 u/kg/hr)
 
 
 
 
 
 
C. Sliding scale - PTT in 60-80 range..
 
 
 
PTT Bolus/Hold Adjust Heparin
 
 
 
<50 70 u/kg 0 Increase 200 u/hr
 
 
 
50-59 0 0 Increase 100 u/hr
 
 
 
60-80 0 0 No change
 
 
 
81-99 0 0 Decrease 100u/hr
 
 
 
>100 0 60min Decrease 200 u/hr
 
 
 
 
 
 
*If 1st PTT after loading dose is > 100 sec do NOT change the infusion rate unless evidence of bleeding
 
 
 
 
 
 
D. The PTT should be checked 4-6 hrs after a new bolus or any change in the infusion dose.
 
 
 
E. Other LABS to check include stool GUIAC qd and CBC (platelets) qd
 
 
 
 
 
 
Duration: DVT or PE --> 5 days of heparin (even if the INR is therapeutic earlier in hospital course)
 
 
 
 
 
 
==Source ==
 
 
 
 
 
1/22/06; DONALDSON (addapted from Lampe)
 
 
 
 
 
 
 
 
 
[[Category:Heme/Onc]]
 

Revision as of 19:08, 20 April 2019

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

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

Contraindications

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

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

See Also

References