Marino The ICU Book 4e, IE

8

Chapter

THE PULMONARY ARTERY CATHETER

A searchlight cannot be used effectively without a fairly thorough knowledge of the territory to be searched.

Fergus Macartney, FRCP

The pulmonary artery catheter is a versatile monitoring device that pro- vides a wealth of information on cardiac performance and systemic oxy- gen transport. Introduced in 1970 (1), the catheter rapidly gained in pop- ularity and became a staple in critical care management in the latter part of the twentieth century. Unfortunately, the benefits of the pulmonary artery catheter as a monitoring device have not translated into a survival benefit in most patients (2–4). As a result, the popularity of the catheter has declined precipitously over the past decade, and use of the catheter is currently reserved for cases of refractory heart failure or life-threaten- ing hemodynamic instability of uncertain etiology (5,6). This chapter presents the spectrum of hemodynamic parameters that can be monitored with pulmonary artery catheters. The physiologic relation- ships and clinical applications of these parameters are described in Chapters 9 and 10. THE CATHETER The pulmonary artery (PA) catheter was conceived by a cardiologist named Jeremy Swan (1), who designed a catheter that is equipped with a small inflatable balloon. When inflated, the balloon allows the flow of venous blood to carry the catheter through the right side of the heart and into one of the pulmonary arteries (like floating down a river on an inflat- able rubber raft). This balloon flotation principle allows a right heart cath- eterization to be performed at the bedside, without fluoroscopic guid- ance.

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