Efficacy and safety of hydroxyethyl starch 6% 130/0.4 in a balanced electrolyte solution (Volulyte) during cardiac surgery

Abstract

Objective: The infusion of large amounts of saline-based solutions may contribute to the development of hyperchloremic metabolic acidosis and the use of a balanced carrier for colloid solutions might improve postoperative acid-base status. The equivalence of 2 hydroxyethyl starch (HES) solutions and the influence on chloride levels and acid-base status by selectively changing the carrier of rapidly degradable modern 6% HES 130/0.4 were studied in cardiac surgery patients.

Design: A prospective, randomized, double-blinded study.

Setting: A clinical study in 2 cardiac surgery institutions.

Participants: Eighty-one patients.

Intervention: Patients received either 6% HES130/0.4 balanced (Volulyte; Fresenius Kabi, Bad Homburg, Germany) or 6% HES130/0.4 saline (Voluven; Fresenius Kabi, Bad Homburg, Germany) for intra- and postoperative hemodynamic stabilization.

Measurements and main results: The therapeutic equivalence of both HES formulations regarding volume effect and superiority of the balanced electrolyte solution regarding serum chloride levels and acid-base status were measured. Similar volumes of both HES 130/0.4 balanced and HES 130/0.4 saline were administered until 6 hours after surgery, 2,391 ± 518 mL in the HES 130/0.4 balanced group versus 2,241 ± 512 mL in the HES 130/0.4 saline group. The 95% confidence interval for the difference between treatments (-77; 377 mL; mean, 150 mL) was contained entirely in the predefined interval (-500, 500 mL), thereby proving equivalence. The serum chloride level (mmol/L) was lower (p < 0.05 at the end of surgery), and arterial pH was higher in the balanced group at all time points except baseline, and base excess was less negative at all time points after baseline (p < 0.01).

Conclusions: Volumes of HES needed for hemodynamic stabilization were equivalent between treatment groups. Significantly lower serum chloride levels in the HES balanced group reflected the lower chloride load of similar infusion volumes. The HES balanced group had significantly less acidosis.