Hydroxyethyl Starch 130/0.4 and the Risk of Acute Kidney Injury After Cardiopulmonary Bypass: A Single-Center Retrospective Study

Abstract

Objectives: To investigate whether using hydroxyethyl starch (HES) 130/0.4 as a pump prime and for intraoperative fluid therapy is associated with postoperative acute kidney injury (AKI) after adult cardiac surgery.

Design: Retrospective observational study.

Setting: University hospital, single center.

Participants: Six hundred six adult patients who underwent on-pump cardiac surgery between April 2013 and June 2014 were included.

Interventions: Until July 2013, balanced HES 130/0.4 (Volulyte(®), Fresenius Kabi AG, Bad Homburg, Germany) was used both as a pump prime (1,500 mL) and for intraoperative fluid therapy (1,000 mL). From August 2013, HES was replaced entirely by a balanced crystalloid solution (Plasma-Lyte A, Baxter, Lessines, Belgium).

Measurements and main results: The primary endpoint was the incidence of postoperative AKI during the first 48 postoperative hours, determined using the Acute Kidney Injury Network classification. Secondary outcomes included kidney function at postoperative day 7, postoperative dialysis or hemofiltration, postoperative pulmonary complications, lengths of intensive care unit and hospital stays, postoperative fluid balance and urinary output, surgical revision for bleeding, and 30-day mortality. Multivariable logistic regression was used to adjust for confounders. AKI occurred in 9.5% of crystalloid patients and in 21.5% of HES patients. Patients who received HES were about twice as likely to develop postoperative AKI as those treated with crystalloids (adjusted OR 2.26; 95% CI, 1.40-3.80; p = 0.02). HES patients also had a significantly more positive fluid balance and a lower urinary output during the first 48 postoperative hours. The incidence of surgical revision for bleeding was greater in the HES group (4.6% v 1.4%, p = 0.02).

Conclusion: This study suggested that using balanced HES 130/0.4 as a pump prime and for intraoperative fluid therapy in adult patients undergoing on-pump cardiac surgery was associated with a greater incidence of AKI during the early postoperative period.

Keywords: HES; acute kidney injury; cardiac surgery; hydroxyethyl starch.