Masimo PVI® Evaluated in 18-Study Meta-Analysis for Ability to Help Clinicians Assess Fluid Responsiveness

Masimo MASI announced today that an 18-study meta-analysis of 665 subjects reported that Masimo's Pleth Variability Index (PVI®), available with Masimo's SET® and rainbow® SET® monitoring platforms, may help clinicians assess fluid responsiveness in mechanically ventilated patients in normal sinus rhythm in the operating room and intensive care unit.1 Clinicians commonly use intravenous fluid administration in the operating room and intensive care unit to attempt to improve blood flow, or cardiac output.2 Administering either too little fluid or too much fluid can increase patient risk. 2 However, traditional "static" monitoring parameters such as central venous pressure (CVP) are considered unreliable to assess fluid responsiveness. 2 Therefore, experts recommend the use of "dynamic" parameters that measure physiologic variation over the respiratory cycle.3 Multiple dynamic parameters have been shown to help clinicians assess fluid responsiveness, but most dynamic parameters require invasive, complex, and/or costly methods. PVI is a measure of the dynamic changes in the Perfusion Index (PI) that occur during one or more complete respiratory cycles, and may show changes that reflect physiologic factors such as vascular tone, circulating blood volume, and intrathoracic pressure excursions. In contrast to other dynamic parameters, PVI is noninvasive, easily obtained with any Masimo SET® or rainbow® sensor, and has no incremental procedural cost. The meta-analysis, published in the Journal of Clinical Monitoring and Computing by Dr. Chu and colleagues from The First Hospital of China Medical University, Shenyang, China, combined the findings from 18 independent studies evaluating the ability of PVI to help clinicians assess fluid responsiveness. The authors reported that the pooled area under the curve (AUC) for PVI to correctly determine fluid responsiveness was 0.88 (95% confidence interval 0.84 to 0.91). The pooled sensitivity of PVI, or its ability to determine whether cardiac output would increase upon fluid administration, was 0.73 (95% confidence interval 0.68 to 0.78). The pooled specificity of PVI, or its ability to determine whether cardiac output would not increase upon fluid administration, was 0.82 (95% confidence interval 0.77 to 0.86). The authors noted that the sensitivity of PVI was greater in the operating room than in the intensive care unit (0.84 vs. 0.56, p=0.00004). The authors also noted that "the applicability of PVI may be limited by potential interference from several factors such as spontaneous breathing activity, arrhythmia, and low peripheral perfusion." Technical factors that may affect PVI include probe malposition and patient motion. For more information on PVI, go to www.masimo.com.