heparin infusion schedule
Last reviewed 01/2018
Check with local guidelines.
Loading dose 5000 iu iv over 5 minutes
Initial infusion 25,000 iu heparin made up in saline to rate 50 ml gives a final concentration of 500 iu/ml, to be started at 2.8 ml/hr (1400 iu/hr)
Check APTT after 6 hours. Adjust according to APTT ratio (APTT: control) as follows:
|APTT ratio||infusion rate range|
|>7||stop for 30 minutes to 1 hour and reduce by 500 iu/hr|
|5.1-7.0||reduce by 500 iu/hr|
|4.1-5.0||reduce by 300 iu/hr|
|3.1-4.0||reduce by 100 iu/hr|
|2.6-3.0||reduce by 50 iu/hr|
|1.5-2.5||no change - target range|
|1.2-2.4||increase by 200iu/hr|
|<2||increase by 400 iu/hr|
After a change of schedule then APTT should be checked again after 10 hours. However if the APTT ratio is > 5.0 then the APTT ratio should be rechecked in 4 hours.