Pulsus paradoxus

An exaggerated inspiratory decline in systolic arterial pressure, typically >10 mmHg, reflecting marked respiratory variation in ventricular filling and stroke volume.

Causes

• Pericardial and myocardial causes

  • Cardiac tamponade

  • Constrictive pericarditis

  • Restrictive cardiomyopathy

  • Right ventricular dysfunction

• Pulmonary and thoracic causes

  • Massive pulmonary embolism

  • Severe asthma

  • Chronic obstructive pulmonary disease (COPD)

  • Tension pneumothorax

  • Pleural effusion

  • Mechanical ventilation with high intrathoracic pressures

• Severe hypovolemia