[Measurement of pulmonary artery occlusion (wedge) pressure using the Swan-Ganz catheter: various pitfalls].

The Swan Ganz pulmonary artery catheter is widely used in the intensive care unit. It allows the determination of important hemodynamic parameters. Among these, pulmonary artery occlusion pressure ("wedge" pressure) is often considered to reflect accurately left ventricular preload and pulmonary capillary hydrostatic pressure. However, many interferences may render data interpretation difficult, especially in patients undergoing mechanical ventilation. This article reviews some of these pitfalls.