A fluoroscopic method to confirm proper catheter position to measure pulmonary artery wedge pressure

The proper position of a catheter to measure pulmonary wedge pressure is usually confirmed by measuring the oxygen saturation of withdrawn blood. However, this method of confirmation is tedious and frequently unsuccessful. A fluoroscopic method to confirm proper catheter position to measure wedge pressure was tested. Between 2 and 5 ml of contrast medium was injected into the artery distal to the catheter tip. Lack of movement for 15 seconds after injection indicated proper catheter position. As judged by the saturation of withdrawn blood and by comparison of wedge and left atrial or ventricular pressure, the fluoroscopic method of confirmation was correct in 71/75 attempts. Thus the fluoroscopic method of confirmation of proper catheter position is simple, rapid, and reliable.