Pleth Variability IndexNoninvasive  >  Continuous

PVI Calculation: How It Works

pvi graph pi min pi max

Perfusion Index (PI) is the ratio of nonpulsatile to pulsatile blood flow through the peripheral capillary bed. PVI is an automatic measure of the dynamic change in PI that occurs during the respiratory cycle.

pvi calculation

The greater the PVI, the more likely the patient will respond to fluid administration.


  • 1 Cannesson M. et al. Br J Anesth. 2008;101(2):200-206.