WHAT IS IT? Drop in blood pressure of more than 10 mmHg during inspiration phase.
- Technically not “paradoxical”. It is merely an exacerbation of normal breathing physiology (small drop in SBP during inspiration)
HOW IS IT DONE? Done via manual blood pressure cuff; inflate above SBP and then deflate slowly (1-2 mmHg per second); the first Korotkoff sound is heard during expiration and then, finally, during both. If the difference between these two pressure readings is the >10 mmHg, it is pulsus paradoxus.
Diff Dx: Used in the evaluation of cardiac tamponade (LR 3.3), pericarditis, COPD, bronchial asthma, restrictive cardiomyopathy, hemorrhagic shock, massive PE, tricuspid stenosis, and mitral stenosis.
- Pulsus paradoxus. Olfa Hamzaoui, Xavier Monnet, Jean-Louis Teboul. European Respiratory Journal Dec 2013, 42 (6) 1696-1705; DOI: 10.1183/09031936.00138912
- Chapter 8: The Chest: Chest Wall, Pulmonary, and Cardiovascular Systems; The Breasts. DeGowin’s Diagnostic Examination, 10e
- Chapter 6: Pulsus Paradoxus. Teaching Rounds: A Visual Aid to Teaching Internal Medicine Pearls on the Wards