**Core Concept**
The Swan-Ganz catheter is a type of pulmonary artery catheter used for hemodynamic monitoring in critically ill patients. It is inserted through a large vein and advanced to the pulmonary artery to measure various hemodynamic parameters.

**Why the Correct Answer is Right**
The Swan-Ganz catheter measures cardiac output, pulmonary artery pressure, and pulmonary capillary wedge pressure (PCWP), among other parameters. It works by injecting a small amount of saline into the pulmonary artery, which is then trapped in the capillary bed, allowing for the measurement of PCWP. This pressure is used as an estimate of left atrial pressure and left ventricular end-diastolic pressure.

**Why Each Wrong Option is Incorrect**
**Option A:** Oxygen saturation is typically measured using pulse oximetry or arterial blood gas analysis, not a Swan-Ganz catheter.
**Option B:** Central venous pressure (CVP) is measured using a central venous catheter, not a Swan-Ganz catheter.
**Option C:** Arterial blood pressure is measured using an arterial line or a sphygmomanometer, not a Swan-Ganz catheter.

**Clinical Pearl / High-Yield Fact**
The Swan-Ganz catheter is also known as a pulmonary artery catheter (PAC) or a flow-directed catheter. It is used to guide fluid management and vasopressor therapy in critically ill patients.

**Correct Answer:** D.