Postoperative fluid therapy is crucial for managing patients' fluid needs, ensuring their physiological stability, maintaining hydration and tissue perfusion, restoring fluid balance, and supporting recovery during the postoperative period. The administration of fluid and electrolytes during the postoperative period depends on a thorough patient evaluation, and no single postoperative fluid regimen suits everyone [1].

The aim of postoperative fluid therapy is to keep the patient normovolemic, maintain an adequate circulating blood volume, optimize organ perfusion, promote wound healing, provide adequate calories to prevent catabolism and prevent complications such as hypovolemia, fluid overload, electrolyte imbalances, and acid-base disturbances.

In postoperative patients, the major principles of management of fluid balance are:

Hypovolemia and hypotension are common postoperative complications, and their important causes include:

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