For the pulmonary capillary wedge pressure to reflect pulmonary venous and left atrial pressures, blood flow must be uninterrupted between the catheter tip and the left heart. This condition exists only in West zone:

Question

Quizplus · Accepted Answer

In West zone III, the pulmonary arterial pressure is greater than the pulmonary venous pressure, which is greater than the alveolar pressure, allowing for continuous blood flow and accurate reflection of left atrial pressure.

For the Pulmonary Capillary Wedge Pressure to Reflect Pulmonary Venous