cardiac catheterization, a diagnostic procedure in which a catheter is introduced through an incision into a large vein, usually of an arm or a leg, and threaded through the circulatory system to the heart. ▪ METHOD: The sterile radiopaque catheter 100 to 125 cm in length ultimately reaches the superior vena cava, and then into the right atrium (or through an artery leading to the left ventricle) and other structures to be studied. The course of the catheter is followed with fluoroscopy, and radiographs may be taken. An electrocardiogram is monitored on an oscilloscope. As the catheter tip passes through the chambers and vessels of the heart, blood pressure is monitored, and blood samples are taken to study the oxygen content. ▪ PATIENT CARE CONSIDERATIONS: An antibiotic is often given the day before the procedure. Cardiac catheterization takes from 1 to 3 hours. The patient has to lie still but may be asked to cough or breathe deeply during the procedure. It is anxiety producing, and the patient needs explanation and emotional support. A young child may need a sedative. The pulse on the operative side and the blood pressure on the other side of the body are monitored at least every 15 minutes for 1 hour and every half hour thereafter. During left heart catheterization, peripheral pulses are also monitored. The temperature may be elevated for several hours, and there may be pain at the incision site. The patient is prevented from bending the hip on the operative side after the study. A sand bag or other counterpressure dressing is applied to the site to prevent bleeding at the insertion site. The nurse observes the site for bleeding and for signs of infection, thrombophlebitis, and cardiac arrhythmia. Cardiac catheterization is typically performed by a special team in a special laboratory. By offering information and counseling, a member of the team may be of great help to the patient before and after the procedure. ▪ OUTCOME CRITERIA: Many conditions may be accurately identified and assessed by using cardiac catheterization, including congenital heart disease, coronary artery disease, tricuspid stenosis, and valvular incompetence. Among the risks of the procedure are local infection, cardiac arrhythmia, and thrombophlebitis.