Perioperative fluid therapy with tetrastarch and gelatin in cardiac surgery--a prospective sequential analysis*.

Objectives: To determine clinical outcomes of synthetic colloids, tetrastarch, and gelatin, used before and after cardiac surgery.

Design: Prospective observational cohort study.

Setting: Fifty-bed cardiac ICU.

Patients: Six thousand four hundred seventy-eight consecutive patients with cardiopulmonary bypass surgery.

Interventions: Fluid therapy in the operating room and on the ICU directed at preset hemodynamic goals: 1) hydroxyethyl starch (predominantly 6% hydroxyethyl starch 130/0.4) in 2004-2006, n = 2,137; 2) 4% gelatin in 2006-2008, n = 2,324; and 3) only crystalloids in 2008-2010, n = 2,017.

Measurements And Main Results: Renal replacement therapy was more common during periods when patients received synthetic colloids compared to only crystalloids. Risk of renal replacement therapy was greater after hydroxyethyl starch (odds ratio, 2.29; 95% CI, 1.47-3.60) and gelatin (odds ratio, 2.75; 95% CI, 1.84-4.16; both p < 0.001) compared to crystalloid. Propensity score stratification confirmed greater use of renal replacement therapy in the hydroxyethyl starch and gelatin periods compared to the crystalloid period (odds ratio, 1.46 [1.08, 1.97]; p = 0.013 and odds ratio, 1.72 [1.33, 2.24]; p < 0.001, respectively). Time to vasopressor cessation, normalization of serum lactate, and mean arterial pressure did not differ among groups. Total fluid requirement was 163 mL/kg in the hydroxyethyl starch period, 207 mL/kg in the gelatin period, and 224 mL/kg in the crystalloid period. Fluid intake was higher in the crystalloid group only during the first 20 hours.

Conclusions: In cardiac surgery patients, fluid therapy with perioperative administration of synthetic colloids carries a high risk of renal replacement therapy and is not more effective than treating with only crystalloids.