Renal effects of synthetic colloids and crystalloids in patients with severe sepsis: a prospective sequential comparison.

OBJECTIVES: Hydroxyethyl starch 200 is associated with renal impairment in sepsis, but hydroxyethyl starch 130/0.4 and gelatin are considered to be less harmful. We hypothesized that fluid therapy with only crystalloids would decrease the incidence of acute kidney injury.

DESIGN: Prospective sequential comparison during intensive care unit stay.

SETTING: Surgical intensive care unit.

PATIENTS: Patients with severe sepsis.

INTERVENTIONS: Changes in standard fluid therapy, with predominantly 6% hydroxyethyl starch from January 2005 to June 2005, 4% gelatin from January 2006 to June 2006, and only crystalloids from September 2008 to June 2009.

MEASUREMENTS AND MAIN RESULTS: Acute kidney injury was defined by the presence of at least one RIFLE class; 118 patients received hydroxyethyl starch, 87 patients received gelatin, 141 patients received only crystalloids. Baseline serum creatinine values were similar. Patients received median cumulative doses of 46 (interquartile range, 18-92) mL/kg hydroxyethyl starch and 43 (interquartile range, 18-76) mL/kg gelatin. Total median fluid amounts were 649 (interquartile range, 275-1098) mL/kg in the hydroxyethyl starch group, 525 (237-868) mL/kg in the gelatin group, and 355 (173-911) mL/kg in the crystalloid group. The difference was statistically significant for hydroxyethyl starch after adjustment for multiple testing. Mean daily fluid intake and fluid balance were higher on days 0 and 1 in the crystalloid group. Acute kidney injury occurred in 70% of patients receiving hydroxyethyl starch (adjusted p = .002) and in 68% of patients receiving gelatin (adjusted p = .025) vs. 47% patients receiving crystalloids. Need for renal replacement therapy tended to be higher in the hydroxyethyl starch group (34%; adjusted p = .086) and in the gelatin group (34%; adjusted p = .162) in comparison to the crystalloid group (20%). Intensive care unit and hospital mortality were similar in each group (hydroxyethyl starch: 35% and 43%; gelatin: 26% and 31%; crystalloids: 30% and 37%).

CONCLUSION: Fluid resuscitation with only crystalloids was equally effective, resulted in a more positive fluid balance only on the first 2 days, and was associated with a lesser incidence of acute kidney injury.