Question

A blood sample taken from a 112.2-lb. patient 6 hours after heparin therapy is initiated shows an aPTT of 24 seconds. Calculate

• (a) the bolus dose (to nearest whole unit) and

• (b) the infusion rate, in mL/hr (to nearest tenth) using the standard heparin concentration IV found at the top of the protocol, according to the adult weight-based heparin protocol (25,000 units in 250 mL (100 units per mL).

Answer 1

The weight of the Patient = 112.2 lb = 50.9Kg
If we take Heparin
25,000 units = 250ml
100 units = 1 ml

(a) Heparin Bolus calculation :

The adult based weight protocol of Raschke for Heparin is
80 units /kg bolus dose followed by an 18 unit /kg /hour
as IV infusion.

1 Kg = 80 units
50.9 kg = 80 x 50.9 = 407.2 units of Heparin

Heparin Bolus = 407units of heparin

Followed by

(b) IV Infusion rate calculation:
18 units/Kg/hour
1 Kg = 18 units
50.9 Kg = 916.2 units

Given:
IV infusion order : 18 units /kg/hr
The bag of Heparin 25,000units/250ml
Patient Weight: 112.2 lb

Solution:

112.2 lbs x 1 kg x 18units/hr x 250ml = 504,900 = 9.18ml/hour
------ ---- --------- ----- -------
1 2.2 lb 1kg 25000units 55,000

ANswer = 9.2 ml/Hour