Comparison of Hydroxyethyl Starch and Ringer Lactate as a Prime Solution Regarding S-100β Protein Levels and Informative Cognitive Tests in Cerebral Injury

Background Cognitive dysfunction (as an indicator of cerebral dysfunction after open heart surgery) was observed in as many as 70% of patients who underwent cardiopulmonary bypass. S-100β protein is a sensitive indicator of cerebral injury. We aimed to compare the effects of hydroxyethyl starch and Ringer lactate prime solutions in the protection of cerebral tissue in cardiopulmonary bypass using serum S-100β protein levels and informative cognitive tests. Methods Patients were randomized into two groups. Open heart surgery was performed by using hydroxyethyl starch solution in group 1 (n = 15) and Ringer lactate solution in group 2 (n = 15). Preoperative, perioperative, and postoperative S-100β protein levels and informative cognitive test scores, clinical and operational characteristics of the patients were compared. Results A significant difference was found only between preoperative and postoperative results of verbal accuracy (human) test in group 1, whereas differences between preoperative and postoperative scores of continuous skill, verbal accuracy (human), verbal accuracy (animal), verbal accuracy (human–animal), go-no-go paradigm, calculation, and abstract thinking tests were significant in group 2 (p ≤ 0.05). The S-100β protein levels were not significantly different between the groups (group p = 0.97). Conclusions Because hydroxyethyl starch prime solution used in extracorporeal circulation had significant positive effects with informative–cognitive tests when compared to Ringer lactate solution, it seems to be a better prime solution to prevent cerebral dysfunction in these patients.