Calibration and Testing of Sensors used During Dialysate Preparation in Hemodialysis Machine

Hemodialysis machines are essential for patients with chronic kidney disease (CKD) as they filter waste products from the blood. To ensure patient safety, the dialysate solution must meet specific parameters, such as temperature, conductivity, pH, and flow rate. This study focuses on the calibration and testing of critical sensors used in the dialysate mixing process, including PT -100 temperature sensors, conductivity sensors, pH sensors, flow sensors, and the pump system. The PT -100 sensor was calibrated within a temperature range of 30°C to 45°C, producing accurate and stable temperature measurements. Conductivity sensors were calibrated using standard solutions with values of 12.88 mS/cm and 1.413 mS/cm, achieving higher accuracy at 12.88 mS/cm. pH sensors were calibrated with buffer solutions of pH 4.01 and 6.86, showing minimal error and consistent readings. Flow sensors were tested to ensure accurate delivery of dialysate components, achieving flow rates of 394.62 mL/min for reverse osmosis (RO) water, 220.41 mL/min for acid, and 298.62 mL/min for base. The pump system was calibrated to mix 500 mL of dialysate in 86 seconds, maintaining the correct ratio of 464.1 mL RO water, 23.3 mL acid, and 12.7 mL base. The results demonstrate that accurate sensor calibration significantly improves the reliability and efficiency of the hemodialysis machine. Proper calibration ensures that the machine maintains stable parameters, enhancing the overall safety and effectiveness of dialysis therapy.