CPT (Certified Phlebotomy Technician) Practice Exam

If a patient has an IV running in their arm, where should you perform the blood draw on the same arm?

1. Above the IV

2. Below the IV

3. Opposite arm

4. Does not matter

The correct answer is: Below the IV

When performing a blood draw on a patient with an IV in their arm, the best practice is to draw blood above the IV. This is because drawing blood from a location below the IV could result in the sample being diluted with the intravenous fluids that are running into the bloodstream, thereby compromising the accuracy of the test results. By selecting a site above the IV, you are ensuring that the blood sample is representative of the patient's own blood content without interference from the fluids being administered. This is a standard protocol in phlebotomy to maintain the integrity of the sample and ensure accurate laboratory results. Choosing the opposite arm is also a valid approach when possible, but in the context where blood must be drawn from the same arm, above the IV is the appropriate site. The option suggesting that it does not matter overlooks the critical importance of sample purity and the potential impact on test outcomes.