Changes in Serum Analytics and Biochemical Urinary Parameters Following Brain Tumor Operation

Background: Changes in the body fluid and serum electrolyte status following major operations, such as brain tumor resection, are always expected. These changes can increase post-operation morbidity and mortality. Objectives: We aimed to evaluate the changes in serum electrolyte levels and renal function parameters in brain tumor patients after operation. Materials & Methods: This cross-sectional study was performed on ۱۶۸ patients with supratentorial tumors in Poursina Hospital, Rasht City, Iran, in ۲۰۲۰. The study parameters included patients’ demographics, hemodynamic stability, serum sodium, potassium, blood urea nitrogen (BUN) and creatinine levels, urine specific gravity, and urinary output, measured immediately and ۱۲ hours after the operation. Results: This study revealed statistically significant increases in serum sodium level (from ۱۳۹.۷۰±۵.۶۰ meq/L to ۱۴۰.۳۴±۶.۲۳ meq/L, P=۰.۰۰۲), urinary output (from ۱۰۴۳.۷۰±۴۵۵.۰۰ mL to ۱۹۶۷.۵۰±۶۶۱.۱۰ mL, P=۰.۰۰۸), urine specific gravity (from ۱.۰۱۰±۰.۰۰۷ to ۱.۰۱۲±۰.۰۰۸, P=۰.۰۱۱), and in serum BUN level (from ۱۷.۴۶±۶.۹۲ to ۱۸.۴۱±۶.۴۰, P=۰.۰۰۱), but significant decrease in serum potassium level (from ۳.۸۸±۰.۴۹ meq/L to ۳.۷۸±۰.۲۸ meq/L, P=۰.۰۱۷) during the first ۱۲ hours after operation. However, the change in serum creatinine level was not significant (from ۱.۱۸±۲.۰۸ mg/dL to ۱.۱۷±۲.۰۸ mg/dL, P=۰.۷۸۷). Conclusion: Significant changes in serum electrolytes (sodium and potassium) and renal function indicators (urine output, specific gravity, and serum BUN) are expected within the first ۱۲ hours after brain tumor operation.