Fluid shifts commonly occur in the perioperative setting and may result in hypo- or hypervolemia. Reasons for such changes in fluid status are multiple, ranging from the underlying disease process (e. g., vomiting, ileus, peritonitis/sepsis) over drug-induced venous pooling (e. g., anesthetics, neuroaxial anesthesia) to postoperative immune activation and sepsis. Both hypovolemia and hypervolemia have been associated with increased morbidity and mortality in surgical patients [
1‐
4]. While hypovolemia mediates organ dysfunction through impaired systemic tissue perfusion [
1,
2], hypervolemia leads to edema formation, fostering secondary complications such as respiratory or renal dysfunction and infection [
3,
4]. Based on this, fluid therapy has become an essential component of perioperative management, particularly of patients with a high risk of death. In this review, the authors summarize the current scientific evidence, recommendations, and their personal experience on perioperative fluid management. …
