I love this question. And if you havne't worked inpatient, I just don't know how you'd answer correctly.
You have to take into consideration of what the hospital IV Heparin Infusion protocol entails. Because aPTT from one institution to next will vary according to the reagent they use.
My response would have been:
1. What is the patient being treated for, MI, PE, DVT, or AF?
2. Has the patient previoulsy received any thrombolytics or IIBIIIA
3. Can I see the IV Heparin Protocol and the sliding scale? Because that's where it will state how to taper or increase the drip rate...
4. Do you run an annual anti-factor X vs. Heparin conc (aptt) nomogram to ensure therapeutic range falls 0.3 - 0.7?
And go from there!
All this information is in the latest CHEST Guidelines... I would suggest you read it..if you haven't!