Final answer:
When performing a procedure on a patient with a unilateral mastectomy, you should use the opposite arm to avoid complications like lymphedema and to ensure better blood flow.
Step-by-step explanation:
If you are performing a procedure on a patient who has undergone a unilateral mastectomy, it is important to draw blood or start an intravenous line (IV) from the opposite arm of the mastectomy. A mastectomy is the surgical removal of one breast, typically to treat or prevent breast cancer. When a breast is removed, the lymph nodes under the arm are often removed as well. This can lead to a condition called lymphedema in the affected arm, which is the build-up of lymph fluid and swelling. Because of this risk, taking blood or placing an IV in the arm on the side of the mastectomy can increase the risk of developing lymphedema. Also, the blood flow may not be as reliable on the side where the mastectomy has occurred. Therefore, it is safer and medically recommended to use the arm that has not been affected by the surgery.
In summary, always use the arm on the opposite side of the mastectomy to reduce the risk of complications such as lymphedema and to ensure better blood flow for the procedure.