Doug is a 39-year-old personal trainer who developed atrial fibrillation about 2 years ago. His doctor put

him on Coumadin. As he is very health conscious, he is compliant with this medication and so, though he

may bleed a little more than before, he doesn’t have any problems. In fact, when he was careless in

cutting a bagel a couple of weeks ago, he was worried that he’d have to go to go to the emergency room.

He was very pleased that it just took a little pressure and a band-aid to stop the bleeding. (It would have

been so embarrassing to admit what he’d done.)
This past week, he was on a long flight from San Francisco to Tampa after attending a friend’s wedding. A

few days after his return, he developed a nasty respiratory infection. He’s sure he caught it on the plane.

He’s tried Theraflu and hot toddies, but just can’t shake it, On Sunday, he decides he can’t stand it any

longer as the cough is keeping from sleeping and his chest is sore. So he goes to a little clinic to see if he

can get some medication to help. The doctor sends him home with a 10-day course of antibiotics.
On Tuesday, Doug feels much better so he decides to go for a run. Just his luck! He trips and falls hard on

the sidewalk, skinning his knees and palms. OUCH! To add insult to injury, he is bleeding like crazy and he

can’t stop it. What a lousy day!
A. Explain why Doug is on Coumadin. Additionally, explain how Coumadin works.
B. Why is he “bleeding like crazy”? (And don’t just state that it’s due to his Coumadin as he was doing fine
before. Explain what has happened to make him more prone to bleeding.)