gelatin + hydroxyethyl starch

Gelatin + hydroxyethyl starch refers to the combined or sequential administration of two distinct synthetic colloid solutions used for intravascular volume expansion. Gelatin is a protein-based colloid, typically succinylated or urea-linked, derived from bovine collagen. Hydroxyethyl starch (HES) is a non-ionic starch derivative, often classified by its concentration (e.g., 6%), molecular weight, and substitution ratio (e.g., 130/0.4). Both agents function by increasing the colloid osmotic (oncotic) pressure of the blood, which draws fluid from the interstitial space into the intravascular compartment to restore circulating volume in patients with hypovolemia or shock. However, clinical evidence, including studies in patients with severe sepsis, has demonstrated that these synthetic colloids are associated with a significantly higher incidence of acute renal failure and an increased need for renal replacement therapy compared to crystalloids.