Influence of saline-based hydroxyethyl starch on umbilical cord blood electrolytes

Hydroxyethyl starch (HES) is widely used to prevent and treat spinal anesthesia-induced hypotension during cesarean section. However, the use of saline-based HES may lead to hyperchloremia. This study aimed to clarify the effects of saline-based HES on umbilical cord chloride level at delivery. We retrospectively analyzed 93 consecutive single-pregnancy patients who underwent cesarean section with combined spinal-epidural anesthesia. The patients were divided into two groups, depending on the use of 6% HES 130/0.4: group A (461 ± 167 ml of saline-based HES was administered; 43 patients) and group B (HES not administered; 50 patients). The major outcome was umbilical cord chloride level at delivery. The volume infused from operating room admission until delivery was not significantly different between groups. The umbilical cord chloride level at delivery was statistically significantly higher in group A than in group B, but clinically similar (108 ± 2 vs. 107 ± 2 mmol/l, P = 0.02). No differences were observed in the Apgar score or other umbilical cord laboratory data at delivery (Na⁺, K⁺, pH, base excess). In conclusion, we suggest that although the use of up to 500 ml of saline-based HES during cesarean section influences umbilical cord blood electrolytes, the effect is not of a clinically significant magnitude.