PVI®Pleth Variability Index
Pleth Variability Index is an automatic measure of the dynamic change in PI that occurs during the respiratory cycle
- > PVI® is a measure of the dynamic changes in the Perfusion Index (PI) that occur during one or more complete respiratory cycles.
- > PI reflects the amplitude of the pulse oximeter waveform and is calculated as the pulsatile
infrared signal (AC or variable component), indexed against the non-pulsatile infrared signal
(DC or constant component). PI is expressed as a percentage
- > The calculation for PVI® is accomplished by measuring changes in PI over a time interval where one or more complete respiratory cycles have occurred.
- > PVI® automatically and continuously calculates the respiratory variations in the plethysmographic waveform.
- > PVI® may show changes that reflect physiologic factors such as vascular tone, circulating blood volume, and intrathoracic pressure excursions.
PVI® Calculation: How It Works
Caution: Federal (USA) law restricts this device to sale by or on the order of a physician. See instructions for use for full prescribing information, including indications, contraindications, warnings, and precautions.