Final answer:
Perform a blood draw distal to the IV site or on another extremity to prevent sample contamination. The median cubital vein in the antecubital region is a common choice but avoid the area with the IV. Consider IV fluid flow principles and blood pressure cuff usage during the procedure.
Step-by-step explanation:
If a patient has an IV running in their arm, the recommended location for performing a blood draw on the same arm would be distal to the IV site or on a different extremity to avoid contamination of the blood sample with IV fluids. However, if drawing from the same arm is necessary, one should choose a site that is distal (away from the torso) from where the IV infusion is being administered. This can sometimes be more challenging due to the patient's vein availability and care should be taken to avoid the area with the IV insertion to prevent complications such as infection or infiltrations. Commonly, the median cubital vein located in the antecubital region is used for drawing blood, as it is the most common site for venous blood draw in humans.
When an IV bag is running, it's typically placed at 0.24 m or higher above the entry point into the arm to facilitate the flow of IV fluids into the bloodstream. In contrast, during blood donation, the blood collection bag is placed lower than the donor's arm to promote blood flow into the bag. This principle should be considered when choosing a site for blood draw on an arm with an active IV line. Additionally, a blood pressure cuff may be used during blood draw to engorge veins by applying pressure, yet care must be taken not to use the same location as the IV insertion site.