Parameters and maintenance methods of hemodialysis machine

The hemodialysis machine is a comprehensive system that includes dialysate heating facilities, dialysate degassing devices, precise configuration of dialysate pH, fixed-volume dehydration closed systems, peristaltic blood pumps, and chemical or thermal disinfection devices. In medical equipment, hemodialysis machines work for a long time and are extremely susceptible to thermal and chemical corrosion, causing wear and tear of components and affecting the performance of the entire dialysis system, which is directly related to the quality and life safety of patients' hemodialysis. Routine maintenance and calibration of hemodialysis machines is a quality control process that must not be ignored.
The hemodialysis machine is divided into two parts: water circuit and blood circuit. The main factors affecting the dialysis effect are: dialysate ratio, dialysate temperature, ultrafiltration volume and blood flow.

1. Dialysate ratio
The composition and concentration of dialysate are set by physicians according to clinical needs. The stability of the components and concentration of dialysate is the guarantee for patients to achieve adequate dialysis. Any deviation from a certain range will cause discomfort to the patient, complications, and may even lead to death. Usually, the dialysate proportioning system consists of electrodes for testing conductivity and liquid A pumps and liquid B pumps. The possibility of proportioning errors also focuses on these two reasons: First, the blockage or leakage of the A liquid pump or B liquid pump, resulting in incomplete proportioning; second, due to the corrosion and precipitation of chemical substances on the electrodes, resulting in concentration monitoring errors. Inaccurate.
Maintenance points:
(1) Adhere to the decalcification and disinfection cleaning process according to standard operating procedures every day and after each dialysis, ensuring the concentration of decalcification solution and disinfectant and the cleaning and disinfection time.
(2) It is recommended that the proportioned dialysate be sent for electrolyte testing once a month.
(3) If there is an error, the cause must be found and corrected.

2. Dialysate temperature
Keeping the temperature of the dialysate constant is the basic condition for maintaining adequate dialysis of blood during extracorporeal circulation dialysis. Temperatures that are too low or too high will cause discomfort to the patient, and temperatures exceeding 41°C will cause hemolytic damage. Although the current hemodialysis machine is equipped with a precise digital temperature control method, the temperature at the remote end is greatly affected by the outside world due to changes in the inlet water temperature and the need for dialysate to be transported outside the machine and exchange blood within the dialyzer. , difficult to control. Especially in hot summer and cold winter, there is a big difference between indoor and outdoor temperatures, which will directly affect the control of dialysate temperature.
Maintenance points:
(1) The water temperature at the water inlet of the dialyzer needs to be checked frequently with an external thermometer. Note that the hemodialysis machine must operate normally for 1 hour before measuring the temperature. The temperature value at this time is relatively correct.
(2) When hot weather turns to cold weather or cold weather turns to hot weather, water temperature monitoring and debugging must be carried out.

3. Dialysate composition: The composition of dialysate is one of the key factors that determine the effect of dialysis. According to the specific conditions of the patient, the composition of the dialysate needs to be adjusted, including electrolyte concentration, temperature and pH value. Commonly used electrolyte components include sodium, potassium, calcium, and chloride, and their concentrations need to be adjusted based on the patient's blood test results.

4. Dialysis time: Dialysis time refers to the duration of dialysis treatment for the patient, which is usually determined based on the patient's renal function status and dialysis plan. Under normal circumstances, dialysis time is 3-4 times a week, 4-5 hours each time.

5. Ultrafiltration rate: Ultrafiltration rate refers to the speed at which excess fluid is removed from the patient's blood during dialysis. Based on the patient's weight, blood pressure, and kidney function, the ultrafiltration rate of the dialysis machine needs to be adjusted to ensure the patient's water balance.

6. Dialysis membrane type: The choice of dialysis membrane directly affects the dialysis effect and patient safety. Common types of dialysis membranes include high-permeability membranes and low-permeability membranes. The appropriate dialysis membrane needs to be selected based on the patient's blood pressure and dialysis clearance effect.

Maintenance method:
Regular cleaning and disinfection: Regular cleaning and disinfection of hemodialysis machines are critical steps to ensure safe operation of the equipment. After each use, the surface and pipes of the dialysis machine should be thoroughly cleaned to remove residual blood and dialysate. Disinfect regularly to kill bacteria and viruses and prevent cross-infection.

Check the pipelines and connections: Regularly check the pipelines and connections of the dialysis machine to ensure they are intact and have no air leakage or blockage. In particular, the blood transfusion lines and intravenous needles of the dialysis machine need to be checked and replaced frequently to prevent blood leakage and infection.

Maintain the stability of the equipment: Regularly check the operational stability and accuracy of the dialysis machine to ensure that its parameters and functions are normal. In particular, the pressure sensor and temperature sensor of the dialysis machine need to be calibrated and adjusted regularly to ensure the safety and effectiveness of dialysis treatment.

Reserve of spare parts and consumables: Maintenance personnel need to reserve spare parts and consumables for dialysis machines in time to prepare for emergencies. This includes dialysis filters, infusion lines, intravenous needles, etc. to ensure the continuity and reliability of dialysis treatment.

In summary, understanding the parameter settings and maintenance methods of the hemodialysis machine is crucial to ensuring the safety and effectiveness of dialysis treatment. Medical institutions and maintenance personnel should strengthen the training and management of dialysis machines, establish a sound maintenance system and work procedures, ensure that each dialysis machine can operate normally, and provide patients with high-quality dialysis treatment.