cardiac index
Also written as: CI — Cardiac Index
Cardiac output normalized for body surface area, expressed in liters per minute per square meter.
Full Definition
Cardiac index is a hemodynamic parameter that represents cardiac output normalized for body surface area, typically expressed in liters per minute per square meter (L/min/m²). Normal cardiac index ranges from 2.4 to 4.0 L/min/m², with values below 2.2 L/min/m² indicating low cardiac output states. This measurement is particularly valuable in cardiac anesthesia as it accounts for patient size differences and provides a more accurate assessment of circulatory adequacy than absolute cardiac output values. Cardiac index is commonly measured using thermodilution techniques via pulmonary artery catheters or estimated using echocardiographic methods.
Usage
Usage note: Commonly abbreviated as CI in clinical documentation.
In Context
- "The patient's cardiac index remained below 2.0 L/min/m² despite inotropic support, indicating persistent low output syndrome." — ICU progress note
- "Cardiac index measurements guided the titration of vasoactive medications in the postoperative period." — Anesthesia record