Cardiac output index

From IDWiki

Definition

  • Cardiac output is the volume of blood pumped by the heart per minute
  • CO = Heart Rate x Stroke Volume
  • CI = CO / body surface area

Methods

  • Echocardiography with Dopplers
  • Thermodilution (historical)
    • 10cc room temperature saline injected into proximal pot
    • Thermistor at tip measures temperature change over time
    • Repeat 3 times within 10% of each other
    • Unreliable with ASV/VSD/PFO or TR
  • Fick equation (historical)
    • Uses spirometry and VO2 measurements
    • VO2 / (k x Hgb x (arterial O2 sat - PA sat)