Download Guidelines for Heparin Therapeutic Dosing: UWHC Protocol and more Summaries Nursing in PDF only on Docsity!
Guidelines for the Therapeutic Dosing of Heparin
Guidelines developed by the UWHC Center for Drug Policy
Revised by: Wendy Horton, PharmD, BCPS Reviewed by: Lisa Gryttenholm, PharmD; Dan Hendrickson, RPh; Jonathan Keevil, MD; Scott Mead, MD; Justin Sattin, MD; Susan Schroeder, RN; William Tanke, RPh; Michelle Thoma, PharmD; Philip Trapskin, PharmD; Eliot Williams, MD; Kenneth Wood, DO
Coordination: Lee Vermeulen, RPh, MS, FCCP โ Director, Center for Drug Policy
Approved by P&T: January 2004 Last Review Date: April 2009 Next Scheduled Review: April 2011
A. The prescriber will initiate the heparin protocol by writing an order to begin heparin per protocol. The order must specify the intended dosing regimen and if an initial bolus is desired.
Low Intensity Regimen โ acute MI treated with alteplase, tenecteplase or abciximab/eptifibatide/tirofiban (note: no bolus is recommended if less than 6 hours from arterial sheath removal)
Medium Intensity Regimen โ non-ST segment myocardial infarction, mechanical valve
High Intensity Regimen โ established deep vein thrombosis, pulmonary embolism, ventricular/atrial thrombus
B. Once the prescriber orders the heparin protocol, the nurse takes the following steps:
1.0 Review initial order for desired dosing regimen (low, medium, high intensity) and whether a bolus is indicated.
Regimen Bolus Dose (units/kg)
Maximum Bolus (units)
Initial Infusion (units/kg/hr)
Maximum Initial Infusion Rate (units/hr) Low 60 4000 12 1000 Medium 70 7000 15 1400 High 80 10,000 18 2000
2.0 Obtain actual body weight. Use best estimate of true weight if unable to weigh patient. Record weight in HealthLink. Make calculations using actual body weight.
3.0 Order labs 3.1 Stat baseline aPTT and INR/PT. 3.2 Hematocrit and platelet count every other day until day 14, beginning the day that heparin is initiated. 3.3 Stat aPTT 6 hours after initiation of heparin. Repeat stat aPTT 6 hours after each dose adjustment (see #7).
4.0 Heparin is a high-alert medication. An additional double-check is required as specified in Hospital Administrative Policy 8.33 must be performed on all boluses, when IV pump programming is outside of the established IV pump decision support software (Alaris Guardrails ยฎ) limits, and when a new bag of heparin is hung.
5.0 Prepare and administer the initial heparin bolus, if one is ordered. If no bolus is ordered, proceed to step 6. 5.1 Document bolus in HealthLink 5.2 Use heparin 1000 units/mL vial for bolus from floor stock.
6.0 Initiate heparin infusion. 6.1 Document infusion rate in HealthLink in mL/hr 6.2 Use heparin 25,000 units/500 mL D5W premixed bags.
7.0 Titration of heparin therapy 7.1 Stat aPTT 6 hours after initiation and 6 hours after any dose change. Adjust heparin infusion as indicated in the dosing adjustment table until aPTT is therapeutic. Use supplemental bolus if ordered. 7.2 Record each heparin rate adjustment on the heparin flow sheet. 7.3 Once three consecutive aPTTs (drawn every 6 hours) are therapeutic, order routine aPTT only every 24 hours. If dose adjustment again becomes necessary, recheck aPTT in six hours and repeat the process.
8.0 If heparin is being used therapeutically, no modification of these protocol orders is allowed. While discouraged, if patient circumstances require heparin dosing that differs from established protocols, specific orders must be written. Separate heparin order sets are available for patients on ECMO or ventricular assist devices.
Low and Medium Intensity (Arterial Thrombosis) Heparin Anticoagulation Dose Adjustments aPTT (seconds) Bolus/Hold Infusion <34 Give supplemental bolus if ordered & inform MD
โ 100 units/hr = โ 2 mL/hr
34-37 Give ยฝ supplemental bolus if ordered & inform MD
โ 100 units/hr = โ 2 mL/hr
38-44 (^0) โ 50 units/hr = โ 1 mL/hr 45-54 0 NO CHANGE 55-64 0 โ 50 units/hr = โ 1 mL/hr 65-84 (^0) โ 100 units/hr = โ 2 mL/hr 85-100 Hold infusion 1 hour & inform MD โ 150 units/hr = โ 3 mL/hr 101-125 Hold infusion 1 hour & inform MD (^) โ 200 units/hr = โ 4 mL/hr
125 Hold infusion 1 ยฝ hour & inform MD โ 200 units/hr = โ 4 mL/hr
High Intensity (Venous Thromboembolism) Heparin Anticoagulation Dose Adjustments aPTT (seconds) Bolus/Hold Infusion <34 Give supplemental bolus if ordered & inform MD
โ 100 units/hr = โ 2 mL/hr
34-44 Give ยฝ supplemental bolus if ordered & inform MD
โ 100 units/hr = โ 2 mL/hr
45-54 (^0) โ 50 units/hr = โ 1 mL/hr 55-70 0 NO CHANGE 71-85 (^0) โ 100 units/hr = โ 2 mL/hr 86-100 Hold infusion 1 hour & inform MD (^) โ 150 units/hr = โ 3 mL/hr 101-125 Hold infusion 1 hour & inform MD โ 200 units/hr = โ 4 mL/hr
125 Hold infusion 1 ยฝ hour & inform MD (^) โ 200 units/hr = โ 4 mL/hr
If two consecutive aPTTs are greater than 125 seconds, patient should not be maintained on the heparin protocol. Recommend consultation with Pharmacy and/or Hematology for assistance with dosing.
If two consecutive aPTTs are subtherapeutic, a consultation with Pharmacy or Hematology is recommended for assistance with dosing.
