Cardiac Exam

Pulsus paradoxus

  • Normally, inspiration ➔ ↑ right sided preload & ↓ left sided preload ➔ small ↓ in BP

    • When RV can't expand to accept ↑ preload ➔ septum shifts leftward ➔ ↓ LV filling ➔ ↓ SV

    • Asthma/COPD exacerbation ➔ ↑ inspiration ➔ ↓ intra-thoracic pressure

  • Difference between:

    • Lowest systolic BP when inspiration causes sounds to disappear

    • and systolic BP when inspiration doesn't cause sounds to disappear

  • How to do it:

    • Slowly deflate cuff while listening for sounds to disappear

      • (make sure pt isn't holding their breath for some weird reason)

    • Deflate the cuff more to determine when sounds become constant despite inspiration