Clinically, hemodialysis treatment of acute and chronic renal failure (end-stage) relies mainly on Dialysis Machines.
Due to the wet, high temperature and acid-alkali conditions in the working environment, many components of the Dialysis Machine are prone to aging failures. Understanding these common failures and providing timely and effective maintenance is of great importance for the maintenance of the machine and for the smooth and orderly treatment of patients.
In the uremia period, the end of renal failure, the kidneys cannot form urine, nor can the metabolic waste generated in metabolic processes in the body and excessive water and electrolytes be excreted in the urine, and the function of the kidneys is substantially or completely lost.
Extensive metabolic waste and excessive water retention in the body lead to serious damage to the body's internal metabolic processes, thus threatening the life and health of the body. At present, the main treatment for end-stage renal failure is to perform hemodialysis through a Dialysis Machine, remove various harmful metabolic wastes and excess water and electrolyte from the body, and maintain a stable and balanced internal environment.
With the rapid development of science and technology, the level of medical equipment has also been rapidly improved. As the main extracorporeal circulation device for the treatment of acute and chronic renal failure in the final stage, Dialysis Machines have become increasingly advanced in design and function. The more complete the course, the better the clinical efficacy obtained, and the higher quality of life and longer life cycle for the patient.
At present, the design and development of Dialysis Machines are more and more mature, but due to a variety of objective reasons, including: the operating environment is characterized by strong acid, strong alkali, cleaning and disinfection methods for chemical disinfection, cold cleaning, thermal disinfection, According to the characteristics of the disease, it takes a long time to continue operation and other reasons, resulting in the loss of equipment components and failure. Therefore, in order to effectively ensure the normal operation of the machine and allow the patient to obtain continuous and stable treatment, it is necessary to be familiar with the common breakdowns of the Dialysis Machines and to be able to perform timely maintenance and maintenance.
The structure and working principle of Dialysis Machines
The Dialysis Machine mainly includes two parts: blood monitoring alarm system and dialysate supply system. The blood monitoring alarm system (ie, the blood circuit section) includes heparin pumps, blood pumps, air monitoring and venous pressure monitoring; the dialysate supply system (ie, the waterway section) includes a temperature control system, a liquid distribution system, a conductivity monitoring system, and degassing. System, blood leak monitoring and ultrafiltration monitoring.
The working principle of the Dialysis Machine: the patient's blood is pumped out through the blood pump, and the heparin pump injects appropriate amount of heparin to perform anticoagulation treatment on the blood, and the dialysate supply system degassing the dialysate concentrate and the dialysis water and heating it according to certain conditions. After mixing, the dialysate is prepared and then the blood and the dialysate act on the hemodialyzer. The blood completes the process of solute diffusion, permeation and ultrafiltration, and then returns to the patient through the air detector. At the same time, the dialysis fluid after the action is leaked. The detector is drained as waste. This process continuously circulates and reciprocates, excreting metabolic wastes and excessive water and electrolytes generated in metabolic processes inside the body, thus achieving the purpose of treatment.
Maintenance of common breakdowns of Dialysis Machines
The structure of the Dialysis Machine is very complicated and there are many accessories. During the entire disease treatment process, the operating environment inside the machine is a highly corrosive environment with strong acids and alkalis, and the treatment process lasts for a long time. In the disinfection process after the end of treatment, the disinfection procedures include chemical disinfection, cold cleaning, thermal disinfection, etc., and the loss of equipment accessories is also very large in varying degrees. Therefore, Dialysis Machines are one of the medical devices that are more prone to malfunction. Its common faults and maintenance plans are summarized below.
2.1 Common Obstacles and Maintenance during Treatment
2.1.1 Dosing system.
The dosing system is used to prepare the dialysate, and the appropriate dialysate is to ensure the smooth and orderly progress of the entire dialysis process. When the dispensing system fails, it will appear
1A, B liquid preparation is not accurate;
Leakage of 2A and B fluid tubes results in a small amount of dialysate, which will cause conductivity alarms.
Therefore, when the conductivity alarm, it is necessary to pay attention to testing and maintenance of liquid distribution system.
2.1.2 Temperature Control System. The temperature control system consists of two parts: heating and temperature detection. The normal standards are: Reverse osmosis water is 36-40°C, dialysate temperature is about 37°C, thermal disinfection temperature is 100°C and maintained for about 10 minutes. When temperature alarms occur, the problems that arise when considering temperature control systems may be:
1 heating rod damage;
2 SCR damage;
3 The temperature sensor is damaged.
Need to overhaul these structures.
2.1.3 Leakage monitoring system. The Dialysis Machine uses the principle of optics to detect hemoglobin in dialysate to find out whether blood leakage occurs during dialysis. The detection sensitivity is 0.25 to 0.35 mL of heme/1 L of dialysate. When the detected result is higher than this range, the optical detector will alarm. Optical detector alarm causes:
1 hemodialysis membrane rupture occurred;
2 The dialysis process was excessively dirty and a false alarm occurred;
3 Direct sunlight leads to false alarms. When these abnormalities occur, it is necessary to promptly remove sediments, check for direct sunlight, and repair the dialysis membrane.
2.1.4 Conductivity monitoring system. The conductivity monitoring system detects the actual conductivity of the dialysate by sequentially inspecting the A liquid and the B liquid, thereby controlling the concentrated liquid preparation system, thereby obtaining a dialysate that meets the standard. The common problems with this system are as follows:
2.1.4.1 The conductance concentration is low. Common causes and treatment methods: (1) The suction tube breaks out or the dialysate is used up, and the suction tube or the dialysate must be replaced; the AB pump works abnormally, and the A pump and the B pump are overhauled.
2.1.4.2 The conductivity concentration is normal and the dialysate channel is lit orange. Common causes and treatment methods: 1 Check the relative speed of the AB pump; 2 The dialysate does not meet the requirements, need to replace the concentrate; 3 The difference between the conductance B and the total conductance is too large, and the conductance needs to be recalibrated.
2.1.4.3 Conductor concentration is too high. Common causes and treatment methods: 1AB liquid suction reversed, need to check the AB liquid; 2 conductance failure, need to re-calibrate the conductance.
2.1.4.4 Conductivity instability. Common causes and treatment methods: 1 There is gas in the liquid, it is necessary to check whether there is air bubble; 2 Conduction fault, need to re-calibrate the conductance.
2.1.5 Degassing system. If gas is present in the dialysate, it may lead to a decrease in the rate of waste removal in the blood, formation of air embolism in the blood, flow and pressure of the dialysate, and influence of the conductivity concentration, etc. Therefore, it is necessary to remove gas from the dialysate. of. Degassing pump and dialysate pressure pump share a single motor. When the motor is running normally, you can see that there is a conical spray in the degassing spray chamber when the motor is turned on. You can see when a malfunction occurs:
No spray, or irregular spray, ie no flow or unstable flow;
Inhalation of the A stream is not normal and the conductivity is low. When these abnormalities occur, it is necessary to pay attention to cleaning the motor, especially the commutator of the motor, and replace the worn carbon brush in time.
2.1.6 Ultrafiltration monitoring system. Hemodialysis is the use of pressure or volume control of transmembrane pressure to achieve the goal of ultrafiltration of excess metabolic waste in the blood and removal of excess water in the blood. The completion of the transmembrane pressure is closely related to the elastic membrane. The elastic membrane is used to complete the processes of pressure regulation, ultrafiltration and pressure balance. However, the service life of elastic membranes is usually 3 to 4 years, after which aging and cracking can occur, resulting in multiple failures. Aging of the pressure regulating membrane of the water supply can cause unstable flow of the dialysate. Once it breaks, it will cause water leakage. The aging of the pressure balance membrane at the input and output of the equilibrium chamber will cause the bypass piping to shake; the ultrafiltration membrane will age, Rupture causes transmembrane pressure instability and is difficult to pass through. When these abnormalities occur, the corresponding membrane needs to be replaced.
2.2 Common Obstacles and Maintenance during Washing and Disinfection
2.2.1 When the small filter elements of V84 and V74 are clogged, they will cause the F01, F02, F03, and F04 disinfectants to fail to meet the standards, and the small filter elements need to be cleaned and flushed.
2.2.2 When the filter of the 89th hole is clogged, it will cause a high flow alarm and need to be cleaned and flushed.
2.2.3 When V87, V30 is damaged, and/or routine maintenance such as disinfection and calcium removal is not in place, it will result in low flow alarms, need to repair or replace V87, V30, and/or disinfection and removal in strict accordance with the operation manual. calcium.
