The blood leak detector is one of the most important safety components of the haemodialysis machine. The task of this unit is to detect the rapture of the dialyzer membrane that would cause the patient’s blood loss. If this device does not detect the blood leakage on time the patient might lose too much blood that can be lethal. Consequently, the fewer blood leakage can be sensed and the more accurate the detection is the safer the therapy is. Especially for patients with renal disease, the minimizing of the blood loss is very important because the body of such patients produces fewer red blood cells than normally since the kidney plays a very important role in the regulation of red blood cell production.
The medical device must meet the requirements of the international standards which also specify the operation of the blood leak detector. In case of acute treatment, the device is mounted on the surface of the haemodialysis machine. Therefore, the measurement can be affected by external disturbances. Despite of such phenomena, the blood leak detector must measure accurately. While preparing my thesis, I got to know this measuring method and then I designed the circuit simulation that helped to develop the real electric circuit of the device mentioned above. Finally, I managed to realize the unit according to the foregoing plans.