Heparin Dosing

Dosing must be individualized according to diagnosis, patient weight and other clinical considerations. The guidelines below are to be used at the physician’s discretion and are not meant to determine the course of therapy.
 
Scientific data indicates that clinical efficacy and safety is optimized if the PTT is maintained at 1.5 to 2.5 times the control. (Hirsh J. Heparin. MEHM 1991; 324: 1565-75) 
 
APTT
(seconds)
Bolus Dose
Stop Infusion (minutes)
Rate Change Units/hour
Repeat APTT
 
< 40
 
5,000 u
 
0
 
Increase 150 u/hr
 
6 hours after change
 
40 – 49
 
2,000 u
 
0
 
Increase 100 u/hr
 
6 hours after change
 
50 – 70
 
0
 
0
 
No change
6 hours then next a.m. and q a.m. if in range
 
71 – 80
 
0
 
0
 
Decrease 50 u/hr
 
6 hours after change
 
81 – 100
 
0
 
30
 
Decrease 100 u/hr
 
6 hours after restart
 
> 100 – 150
 
0
 
60
 
Decrease 150 u/hr
 
6 hours after restart
 
> 150
 
0
 
60
 
Decrease 200 u/hr
 
6 hours after restart