Continuous pulmonary artery pressure (PAP) and intermittent pulmonary artery wedge pressure (PAWP) measurements provide important information about left ventricular function and preload. You can use this information not only for monitoring but also for aiding diagnosis, refining your assessment, guiding interventions, and projecting patient outcomes.

Nearly all acutely ill patients are candidates for PAP monitoring—especially those who are hemodynamically unstable, need fluid management or continuous cardiopulmonary assessment, or are receiving multiple or frequently administered cardioactive drugs. Use of a pulmonary artery (PA) catheter is generally recommended for assessing intravascular volume, particularly in patients with severe pulmonary edema, heart failure, or oliguric renal failure; guiding therapy in severe refractory shock or multiple-organ-dysfunction syndrome; and guiding therapy to maximize oxygen delivery to tissues in some selected patients.

A PA catheter can have up to six lumens, allowing more hemodynamic information to be gathered. In addition to distal and proximal lumens used to measure pressures, a PA catheter has a balloon inflation lumen that inflates the balloon for PAWP measurement and a thermistor connector lumen that allows cardiac output measurement. Some catheters also have a pacemaker wire lumen that provides a port for pacemaker electrodes and measures continuous mixed venous oxygen saturation. (See PA catheters: From basic to complex.)

The PA catheter is inserted into the heart’s right side with the distal tip lying in the pulmonary artery. Left-sided pressures can be assessed indirectly.

No specific contraindications for PAP monitoring exist. However, some patients undergoing it require special precautions. These include elderly patients with pulmonary hypertension, those with left bundle-branch heart block, and those for whom a systemic infection would be life-threatening.