Masimo - PVi Root
  • 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 (0.02-20%).
    Masimo - PVi - PI Formula
  • 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

Masimo - PVi Formula
Masimo - PVi Graph



Follow the link for available PVi studies.

Masimo - Brochure Perioperative Care Solutions

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.