Many sick patients have central intravenous lines (central IVs) so that they can receive medicines or fluids. Central IVs are long, thin tubes that are put into large veins, usually in the neck or upper chest area. They can stay in place longer than the regular types of IVs, which are usually placed in the smaller veins of the arms. When patients need blood tests, it is possible to draw blood samples from central IVs. Doing this can help avoid multiple painful needle sticks. However, experts have discouraged the use of central IVs to take samples for blood cultures, which are done to look for infection in the bloodstream. The concern is that blood cultures from central IVs may be “contaminated.” This means that they may suggest infection when there really is no infection.