Correlation of Pleth variability index PVI with pulse pressure variation PPV and Central Venous Pressure (CVP) for intraoperative Goal Directed Fluid Therapy in patients undergoing Renal Transplantation – A Prospective Observational Study

Chronic kidney disease is an abnormality of kidney structure or function that is present for more than 3 months. CKD may be due to multiple etiology. Best outcome following renal transplantation is mainly based on the intraoperative hemodynamic parameters such Blood pressure, central venous pressure and fluid status. In renal transplant surgery optimal fluid resuscitation is extremely important so as to ensure successful outcomes. It is a standard practice to measure fluid status using static measures of fluid responsiveness such as Central Venous pressure CVP. More recently dynamic measures of fluid responsiveness such as Pulse Pressure Variation PPV and stroke volume variation SVV have also been shown to be reliable indicators of fluid responsiveness and  being followed as a standard of care during renal transplantation. Both these measures require placement of invasive lines. Plethysmography Variation Index PVI has been introduced as a non-invasive dynamic measure to assess the fluid status, predict fluid responsiveness, and guide goal-directed fluid Therapy. PVI, a measurement only available with Masimo SET® pulse oximetry, is the first commercially available index that automatically and continuously calculates the respiratory variations in the photoplethysmogram from data collected noninvasively via a pulse oximetry sensor. 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. The lower the PVI number, the less variability there is in PI over a respiratory cycle. The higher the variability, the more likely the patient will respond to fluid infusion with an increase in cardiac output. This sensor also provides immediate and continuous hemoglobin SpHb measurement by spectrophotometry and helps in non-invasive continuous estimation of Haemoglobin. The primary objectives of this study is to study the correlation between pleth variability index PVI measured noninvasively by using Massimo rainbow pulse co oximetry with pulse pressure variation PPV and central venous pressure CVP for measuring fluid status of patient for intraoperative goal- directed fluid therapy in patients undergoing Renal Transplantation.