In light of a paucity of robust evidence this is a suggested practical approach. Some UK centres use once daily dosing if extended prophylaxis is prescribed for patients over 100kg. These doses are “off-licence”. 

 

Patient weight Less than 50kg 50-100kg 100-150kg Greater than 150kg
Dalteparin 2500 units once daily (off-licence dose) 5000 units once daily 5000 units twice daily* (off-licence dose) 7500 units twice daily* (off-licence dose)

*Removal of epidural catheters

Because at least 12 hours should elapse between epidural catheter removal and administration of dalteparin (Table J, line 3, page 14) the dalteparin dose after catheter removal should be omitted.

Because epidural catheters should be removed in the morning it follows that the evening dose that day should be omitted.