In cardiogenic shock, which physical parameter typically indicates fluid overload?

In cardiogenic shock, increased pulmonary capillary wedge pressure (PCWP) is a key indicator of fluid overload. This parameter reflects left atrial pressure and can be used to estimate the pressure in the pulmonary circulation. When there is fluid overload, it leads to an increase in the volume of blood in the lungs, resulting in elevated PCWP. This elevation suggests congestion in the pulmonary venous system due to the heart's inability to effectively pump blood forward, ultimately leading to impaired gas exchange and pulmonary edema.

The other parameters such as increased heart rate, increased blood pressure, and increased systemic vascular resistance can be associated with various responses in cardiogenic shock but do not specifically indicate fluid overload. Increased heart rate is a compensatory response to decreased cardiac output, while increased blood pressure can be variable and may not always reflect volume status. Increased systemic vascular resistance often occurs in response to overall poor perfusion, but does not directly measure fluid balance in the context of cardiogenic shock. Thus, the primary significance of increased PCWP is its direct link to fluid overload in this clinical state.