Pulmonary edema and impaired ventilation occur during which type of shock?

• A. Septic shock
• B. Cardiogenic shock
• C. Neurogenic shock
• D. Anaphylactic shock

Answer: (B)

Pulmonary edema and impaired ventilation arise when the heart can’t pump effectively, causing a backup of pressure into the lungs. In cardiogenic shock, the left ventricle fails to eject blood, raising left atrial and pulmonary capillary pressures. Fluid leaks into the interstitial and alveolar spaces, flooding the airways, stiffening the lungs, and worsening gas exchange, which produces difficulty breathing and signs like crackles. The other shocks involve different mechanisms—septic shock mainly involves systemic vasodilation and maldistributed perfusion, neurogenic shock is due to loss of sympathetic tone, and anaphylactic shock combines vasodilation with airway edema and bronchospasm—so they don’t produce the classic left-sided heart failure–related pulmonary edema seen in cardiogenic shock.