Pulsus Paradoxus is indicated by what change in blood pressure?

Pulsus paradoxus is characterized by a notable drop in blood pressure during inspiration. Normally, there is a slight decrease in blood pressure during inhalation due to changes in intrathoracic pressure and venous return, but in the case of pulsus paradoxus, this drop is exaggerated, often exceeding 10 mmHg. This phenomenon is typically seen in conditions such as cardiac tamponade, severe asthma, or chronic obstructive pulmonary disease (COPD).

When the patient inhales, the increased negative pressure in the thoracic cavity decreases venous return to the heart, leading to a reduced stroke volume and, consequently, a decrease in blood pressure. The significant distinction of pulsus paradoxus is the presence of this pronounced variation, which can be clinically significant and used as a diagnostic tool.

Understanding this process helps healthcare providers identify underlying conditions that may result in hemodynamic instability during respiratory cycles, enabling timely intervention.