Principles of pulmonary artery catheterization in the critically ill

The pulmonary artery catheter (PAC) may be helpful in determining the etiology of shock, lactic acidosis, pulmonary edema, oliguric renal failure, pulmonary hypertension, and a number of cardiac abnormalities. In addition, it may also be useful in guiding fluid and vasoactive therapy. However, although hemodynamic data from the pulmonary artery catheter (PAC) is widely used diagnostically and therapeutically in the care of critically ill patients, the use of the catheter has not been shown to provide outcomes benefit. In fact, there is some evidence to suggest that placement of the PAC may actually be detrimental. The reasons for this are unclear, but it has been shown that both physicians and nurses frequently misinterpret waveforms and other data obtained from the PAC. Presently, there are a number of ongoing randomized, controlled trials investigating the use of the PAC in specific clinical situations and/or patient populations as well as using specific treatment strategies. In the meantime, if any benefit is to be achieved, it is imperative that clinicians have a thorough understanding of the indications, contraindications, complications, and pitfalls of data interpretation prior to using the catheter. These are reviewed in this article.