Effect of Iodinated Contrast Media on Serum Electrolyte Concentrations in Patients Undergoing Routine Contrast Computed Tomography Scan Procedure

BACKGROUND AND OBJECTIVES: Being hypertonic solutions, iodinated contrast media such as iohexol can cause a shift of fluids and electrolytes between different compartments of the body, but there is an ongoing discrepancy in data and current studies as to the effect of iodinated contrast media on serum electrolytes. Hence, this hospital-based prospective clinical observational study was carried out with objectives of evaluating the changes in serum electrolyte concentrations with intravenous iodinated contrast media administration in adult population and to correlate the changes in electrolyte concentrations, if any, with the demographic profile of the patients. MATERIALS AND METHODS: We analyzed 103 numbers of adult patient samples over a period of 2 months by collecting blood both before administration of contrast and after 24 h of the contrast-enhanced computed tomography scan procedure. Serum concentrations of sodium, potassium, chloride, and ionized calcium were measured using Eschweiler Combiline analyzer based on ion-selective electrode principle. RESULTS: The mean age of the study population in our study was 40.11 ± 20.51 years. We found that changes in serum sodium and chloride concentration after administration of contrast media are significant (sodium: 136.29 ± 3.53 vs. 132.49 ± 6.36 mmol/L and chloride: 100.03 ± 0.70 vs. 97.53 ± 0.70 mmol/L). Sodium concentration shows more decrease in females compared to males after administration of iodine contrast. The most probable reason for this decrease in serum electrolytes was secondary changes to hemodilution due to high osmolality of the contrast. CONCLUSIONS: Attending physicians must be alert for such possibilities of changes in electrolytes after contrast administration and be prepared to treat any adversity if one occurs.