Perioperative Fluid Management Guided by Dynamic Hemodynamic Indicators

Static filling pressures correlate poorly with fluid responsiveness, prompting widespread adoption of dynamic hemodynamic indicators such as stroke volume variation (SVV), pulse pressure variation (PPV), and the plethysmographic variability index (PVI) to guide perioperative fluid administration. This review synthesizes the physiological basis of these indices, their diagnostic accuracy across surgical settings including cardiac, thoracic, laparoscopic, and orthopedic procedures, and the outcome evidence from goal-directed fluid protocols built around them. Diagnostic accuracy for SVV and PPV is strong under controlled ventilation with adequate tidal volume and sinus rhythm, but degrades meaningfully with low tidal volume protective ventilation, one-lung ventilation, arrhythmia, and pneumoperitoneum, while PVI offers a noninvasive alternative that is itself confounded by low peripheral perfusion states. Outcome trials, particularly within enhanced recovery colorectal surgery programs, show that dynamic-index-guided therapy reliably outperforms liberal or unstructured fluid administration but shows less consistent benefit when compared against a well-designed restrictive fluid protocol. We conclude that dynamic indicators are best applied within their validated physiological preconditions and as an adjunct to, rather than a replacement for, a restrictive-leaning baseline fluid strategy and integrated clinical judgment.