Introduction

Swan, Ganz and colleagues were the first to describe the use of a flow-directed, balloon-tipped catheter for the catheterization of the right heart and the pulmonary artery (PA) in 1970. Since then, the PA catheter (PAC) has become a widespread monitoring tool in the management of critically ill patients. Its use necessitates profound knowledge of cardiovascular (patho)-physiology and exhaustive information on current evidence guiding patient selection, particularly in the light of ongoing controversy on its safety and efficacy.

The pulmonary artery catheter

The commonly used PAC has a circumference of 7.0, 7.5 or 8.0 French and is 110 cm long with distances marked at 10-cm intervals. The standard PAC contains four separate internal lumens.

Distal lumen and proximal lumen

These lumen lead to the distal port at the tip of the catheter and to a second port approximately 30 cm proximally to the catheter tip. The distal lumen is used to measure PA pressure (PAP) and sample mixed venous blood, whereas the proximal lumen serves to measure central venous pressure (CVP).

Third lumen

This lumen leads to a balloon just proximal to the catheter tip. Inflating the balloon enables placement of the catheter in the PA and to measure PA occlusion pressure.

Fourth lumen

The fourth lumen contains wires leading to the temperature thermistor located proximally to the balloon. The thermistor enables measurement of blood temperature for the calculation of cardiac output (CO).