Pericardiocentesis is a non-surgical procedure that involves removing fluid from the membrane surrounding the heart. It’s performed as both a test and a treatment. In this procedure, your doctor will give you a mild sedative and a local anesthetic on your chest. A needle will be inserted into your chest just below the breastbone or below your left nipple and guided toward your heart with the help of ultrasound or an echocardiogram. Once the needle reaches the sac surrounding your heart, the fluid will be removed through the needle or, in some cases, with a catheter tube inserted over the needle. The fluid can be drained as a treatment or collected and tested to help determine the cause of excess fluid. Most people stay in the hospital for one or two days after the procedure.