Non-invasive goal-directed fluid therapy with the pleth variability index (PVI): a systematic review and meta-analysis.

Optimal intraoperative fluid management is essential to improve surgical outcomes and reduce complications. The Pleth Variability Index (PVI), a dynamic and non-invasive indicator of fluid responsiveness, has been proposed as a tool for goal-directed fluid management. This systematic review and meta-analysis aimed to evaluate the effectiveness of PVI-guided fluid therapy compared to conventional fluid management (CFM) in non-cardiac surgeries. A comprehensive search of PubMed, Embase, and Cochrane databases up to January 2024 identified eligible studies. Primary outcomes included total intraoperative fluid volume and crystalloid administration. Secondary outcomes included hemodynamic parameters, renal function markers, acid-base balance, and hospital length of stay (LOS). Random-effects models were applied, and subgroup and sensitivity analyses were performed. Nine studies comprising 1,105 patients were included. Compared to conventional fluid management, PVI-guided therapy significantly reduced total fluid volume (mean difference [MD] - 761.23 mL; 95% CI - 1267.42 to - 255.03) and crystalloid administration (MD - 655.05 mL; 95% CI - 1096.48 to - 213.62), without significant differences in colloid use, urine output, norepinephrine requirement, arterial pressure, acid-base balance, or LOS. Subgroup analysis of abdominal surgeries confirmed the observed reduction in fluid volumes. PVI-guided fluid management allows for a more restrictive and individualized approach without compromising hemodynamic or metabolic stability. While the heterogeneity across studies limits generalizability, these findings support the clinical value of PVI as a non-invasive tool for perioperative fluid optimization, especially in settings where invasive monitoring is not feasible. Further trials are needed to evaluate its impact on long-term outcomes.