Abstract
The pulmonary artery catheter has helped elucidate the pathophysiology of many diseases. However, the correct position of the transducer, elimination of the resonance artifact, and making readings at the end-expiratory phase are mandatory to measure pulmonary and wedge pressures correctly. Cardiac output obtained by a bolus injection of cold water is the mean value of a few strokes rather than the mean value of cardiac output for a few minutes, thus it is affected by respiratory phase when an indicator is injected. A recently developed method to measure continuous cardiac output is expected to overcome some unfavorable aspects of the bolus method. It cannot detect rapid changes of cardiac output because it expresses the mean value over a 10 minute period or longer.
There has been no definite standard for applying the pulmonary artery catheter to patients. However, it can contribute to the life support of critically ill patients when it is used precisely with correctly obtained measurements.
