In all the chapters the Case Studies represent situations similar to those that the medical assistant may encounter in daily practice. Students are encouraged to consider the case study as they read each chapter.

A young man comes into the office to have a PT drawn. As you examine the antecubital fossa in his arm, you don't feel confident with the vein but you attempt the phlebotomy anyway, using an evacuated system. However, the vein collapses and you are unsuccessful in your attempt. As you turn away to gather your supplies to try the collection again, he informs you that he is bleeding rather heavily from the venipuncture site and requires your attention.

As you read this chapter, consider the following questions:

1. What and where is the antecubital fossa?

2. What is the principle of the evacuated collection system?

3. How should you attempt to collect the blood on the second try?

4. What type of a blood test is a PT?

5. What could have caused the extensive bleeding this patient experienced after the venipuncture?