Abstract PR095

Abstract

Background & Objectives: Dynamic indicators of fluid responsiveness have been established to be more accurate indicators of preload than static indicators such as Central Venous Pressure. Our aim was to assess the correlation between a non invasive dynamic indicator, Plethysmography Variability Index (PVI) and Systolic Pressure Variation (SPV) as a measure of fluid responsiveness. Materials & Methods: A prospective experimental study was conducted on 50 ICU patients over one year. After inclusion criteria were met in prospective subjects, vital parameters including blood pressure (systolic, diastolic and mean), heart rate, and Oxygen Saturation (SpO2) were recorded. Central venous pressure was also recorded if central line was present. Simultaneous measurement of SPV from an invasive arterial line trace and PVI using pulse-oximetry was carried out. A fluid challenge was administered with 20 ml/kg Ringer’s Lactate fluid over 10 min. Vital parameters, SPV and PVI were recorded every 5 min till 30 min after the fluid challenge. Results: Based on a cut of a baseline SPV of 10 %, the sample group was divided into two sub groups; Fluid Responders (32) and Non Responders (18). Baseline values of PVI were found to be significantly higher in the responder group (22.8±9.5) vs. the non responder group (14.7±5.5), (p < 0.001). Pearson correlation coefficient also showed positive correlation (r = 0.6, p=0.001) between baseline PVI and SPV values. Similar findings were observed even after 15 minutes and 30 minutes of fluid challenge (r=0.4). A threshold vale of PVI more than 18% before volume expansion differentiated fluid responders and non responders with a sensitivity of 75 % and specificity of 67 % with area under ROC of 0.78, which was in keeping with other similar studies.Conclusion: There exists a positive correlation between SPV and PVI, which justifies the use of PVI in a clinical setting of hypotension suspected to be due to hypovolemia, because of its non invasiveness and ease of use. Although more studies are required, especially in an ICU setting, before it becomes an established tool for the same.