Paradoxical pulse

Specialty: Cardiovascular.

• pulsus paradoxus
• inspiratory drop in systolic blood pressure of cardiac origin

Why it occurs

• Cardiac tamponade
• Constrictive pericarditis
• Bronchial asthma attack with severe airway obstruction
• Reacerbated chronic obstructive pulmonary disease (COPD) with severe air trapping
• Massive pulmonary thromboembolism with right ventricular dysfunction
• Acute right ventricular myocardial infarction

Initial workup

Emergency transthoracic echocardiogram to confirm the presence of significant pericardial effusion, diastolic collapse of the right ventricle or systolic collapse of the right atrium, as well as the inspiratory variation of mitral (>25%) and tricuspid (>40%) transvalvular flows; Arterial blood gases to document hypoxemia and respiratory failure; 12-lead electrocardiogram; Multidetector computed tomography of the chest if pulmonary thromboembolism or aortic dissection involving the pericardium is suspected.

Standard management

• High flow supplemental oxygen — to correct tissue hypoxemia secondary to altered ventilation-perfusion
• 0.9% isotonic saline solution — rapid intravenous infusion of 250 to 500 mL to expand intravascular volume and temporarily optimize ventricular filling in case of cardiac tamponade, while pericardiocentesis is performed
• Salbutamol — in case the pulsus paradoxus is secondary to severe bronchospasm; 2.5 to 5 mg nebulized with oxygen to decrease extreme negative intrathoracic pressure
• Methylprednisolone (systemic glucocorticoid if the underlying cause is severe decompensated asthma or COPD; 40 to 125 mg intravenously every 6 to 8 hours).