In the context of Swan-Ganz catheterization, what does 'wedge' refer to?

The term 'wedge' in the context of Swan-Ganz catheterization specifically refers to the technique used to assess left atrial pressure. When the catheter is advanced into the pulmonary artery and then occluded, it allows for the measurement of pulmonary capillary wedge pressure (PCWP). This pressure is reflective of left atrial pressure, providing crucial information regarding the patient's hemodynamic status, particularly in conditions such as heart failure or pulmonary hypertension.

Understanding the significance of this measurement is vital for clinicians as it aids in the management of fluid status and cardiac function. The concept of 'wedge' indicates that the catheter is effectively 'wedged' into a branch of the pulmonary artery, allowing it to measure the pressure in the capillaries supplying the lungs, which correlates closely with the pressure in the left atrium, thus making it a valuable diagnostic tool in critical care settings.