What is a potential hemodynamic consequence of high PEEP?

• A. Reduced venous return leading to decreased cardiac output and possible hypotension
• B. Reduced airway pressures
• C. Increased renal perfusion
• D. Improved cardiac output

Answer: (A)

High PEEP raises intrathoracic pressure, which compresses the great veins and reduces venous return to the right heart. With less filling (preload), the heart pumps out a smaller amount of blood (lower stroke volume), so cardiac output falls. If CO drops enough, blood pressure can decrease, leading to hypotension. This is the key hemodynamic consequence of high PEEP.

High PEEP does not reduce airway pressures; it actually increases them, so reduced airway pressures isn’t accurate. Reduced renal perfusion, while possible as a downstream effect of lower cardiac output, is not the direct hemodynamic consequence the question highlights. Improved cardiac output would be the opposite of what high PEEP tends to do.