NREMT Paramedic Practice Exam 2025 - Free Paramedic Practice Questions and Study Guide

Pulsus paradoxus refers to an abnormal drop in systolic blood pressure during inspiration. Typically, during normal respiratory cycles, the systolic blood pressure may fluctuate slightly but not significantly. However, in conditions such as cardiac tamponade, severe asthma, or chronic obstructive pulmonary disease (COPD), the negative intrathoracic pressure created during inspiration can lead to increased venous return to the right heart. This can cause a drop in the left ventricular stroke volume during inspiration, subsequently leading to a significant decline in systolic blood pressure, typically of more than 10 mmHg.

This phenomenon is clinically relevant because it can indicate underlying respiratory or cardiac conditions, and recognizing it can be essential for appropriate diagnosis and management. Other options like diastolic blood pressure, pulse rate, and respiratory rate do not experience this characteristic drop associated with pulsus paradoxus.