Plethysmography Variation Index versus Pulse Pressure Variation as an Indicator of Fluid Responsiveness in Colorectal Surgeries during Immediate Postoperative Period

Abstract

Abstract Objective Goal directed fluid therapy during major abdominal surgery may reduce postoperative morbidity. The Plethysmography Variability Index (PVI), derived from the pulse oximeter waveform, has been shown to be able to predict fluid responsiveness in a number of surgical circumstances. In this study, we will compare the effectiveness and re liability of Plethysmography variation index (PPV) and Pulse pressure variation (PPV) in prediction of fluid responsiveness in all sedated intubated mechanically ventilated patients admitted for postoperative resuscitation in our surgical ICU. Method 100 patients were placed in two different groups equally where heart rate, PPV, CI, and PVI were recorded on admission. Immediately after volume expansion is performed by infusing saline 500 ml over 30 mins and at the end of volume expansion PPV, CI, PVI will be recorded every 2 hours for the first 24 hours. Results Hundred patients aged from 18 to 64 years who were scheduled for colorectal surgery and were to be transferred to the intensive care unit for postoperative care for the f irst 24 hours post operatively who didn’t have any of the exclusion criteria were included in this prospective randomized comparative single blinded research. 100 patients were divided in to “responders” and “non responders”. Both groups received a volume 500 ml saline over 30 minutes immedietly postoperatively. Fluid responsiveness was tested in both groups using PVI (Plethysmography variability index) and PPV ( pulse pressure variation) using cardiac index as a reference parameter. PVI showed accurate fluid responsiveness in comparison with PPV in responders with mean ranging from ( (-6.66 ± 0.90) and (-5.89 ± 1.93) respectively, with a P-value<0.01 Conclusion This study revealed that after giving a fluid challenge of 500 ml of saline over 30 minutes, a rise in PVI and PPV was demonstrated using cardiac index as a reference for reliability for comparing the effectiveness and accuracy between PVI and PPV.comparing the effectiveness and accuracy between PVI and PPV.PVI and PVI and PPV PPV can be used can be used in assessment of fluid responsiveness of the intubated ventilated sedated patients in assessment of fluid responsiveness of the intubated ventilated sedated patients with sinus rhythm in ICU, and both methods can be performed at the bedside, but with sinus rhythm in ICU, and both methods can be performed at the bedside, but PVI has advantage of being continuousPVI has advantage of being continuous, operator independent, and more reliable, operator independent, and more reliable thanthan PPVPPV.