The aim of the study was to determine postoperative insulin-resistance in patients subject to total thyroidectomy, the prevalence of subjective feelings of hunger immediately before surgery, and the incidence of nausea/vomiting after surgery in patients prepared for elective operations by means of oral glucose solutions.Material and methods. The study group comprised 115 patients, including 71 patients prepared for surgery by means of oral glucose solutions (12.5% glucose) administered 12 and 3 hours before the procedure, at a dose of 800 and 400 ml. The control group comprised 44 patients prepared for surgery by means of the traditional manner- the last meal was served before 2pm the day before the surgical procedure, while fluids before 10pm. Considering both groups, we evaluated glucose and insulin levels three times, as well as determined the insulin-resistance ratio (HOMA-IR) 24 before, and 12 hours and 7 days after surgery. The incidence of nausea and vomiting after surgery, and the subjective feeling of hunger before surgery were also evaluated.Results. Statistically significant differences considering insulin level and HOMA-IR values were observed during the II and III measurements. The glucose and insulin values, and the HOMA-IR insulin-resistance ratio, showed no statistically significant differences during measurement I. No statistically significant glucose level differences were observed during measurements II and III. A significantly greater subjective feeling of hunger before surgery and nausea/vomiting afterwards were observed in the control group.Conclusions. The preparation of patients with oral glucose solutions decreases the incidence of postoperative (thyroidectomy) insulin-resistance, and occurrence of nausea/vomiting during the postoperative period.