With the development of science and technology, medical
endoscopes have been widely used in the medical field. It is one of the important tools for humans to peek and treat internal organs. Common faults of the light source system, common faults of the artificial pneumoperitoneum system, common faults of the liquid pressurization system, common faults of the electrocoagulation and resection system, common faults of the power, ablation system, flushing and suction often occur during the use of medical endoscopes. Common system faults, below we will tell you how to solve these faults.
The medical endoscope system is mainly composed of a high-definition camera host, a high-definition camera, a high-definition monitor, a cold light source, an insufficiency machine, a high-frequency electrosurgery, various endoscopes and other special supporting surgical instruments. Among them, high-definition monitors, high-definition camera hosts, cameras, cold light sources, pneumoperitoneum machines, and high-frequency electrosurgical units are placed from top to bottom on a special laparoscopic work trolley. They are easy to move and flexibly serve the diagnosis and treatment of different departments. The working principle of the medical endoscope system is to probe the endoscope into the human body cavity. The light emitted by the cold light source is irradiated into the body cavity through the beam inside the endoscope. The reflected light signal is sensed by the CCD and converted into The electrical signal is transmitted to the high-definition camera host for further optimization and processing, and then transmitted to the high-definition monitor to obtain clear and realistic images of the body cavity. Its working methods are divided into two types: non-invasive and traumatic: the former refers to sending the endoscope through the same cavity of the human body as the outside world, and intuitively inspects and treats the cavity, such as gastroenteroscopy and bronchoscopy. , nasopharyngoscope, etc.; the latter is an endoscope sent through a surgical incision to examine the closed body cavity and carry out further treatment, such as laparoscopy, hysteroscopy, arthroscopy, etc.
1. Common faults of light source systems
(a) The light is dim. Except for the reason that the grating is blocked, it is basically certain that the bulb is nearing its service life, and it can be replaced with a new one. The service life of xenon light bulbs is generally designed to be 500 hours. If the light source system has a life timing device, this problem can be easily solved.
(b) The light bulb does not light up when turned on. If the cause of burning out the bulb is ruled out, then the problem often lies in the high-voltage ignition circuit of the host machine, because when the machine is turned on, it will generate pulse high voltage of tens of thousands of volts, and the components will age very quickly. Note that you cannot use a multimeter to check the pulse high voltage at this time.
2. Common faults of artificial pneumoperitoneum system
(a) The pressure display is incorrect. This may be caused by damage to the gas pressure sensor. If the machine is designed with a set of multiple differential pressure sensors working at the same time, generally when one of them is aging or contaminated and cannot work, we need to replace all the sensors in this set. Otherwise, only one of them will be replaced, and the others will be replaced. The lifespan of the sensors in the same group is also close to critical.
(b) Flow rate is inaccurate. If the gas flow sensor is damaged, replace it. Sometimes the flow rate is calculated based on the pressure difference. At this time, we need to replace the pressure difference sensor with a new one.
(c) The equipment is leaking. Many cases are caused by the aging of equipment seals. However, there are also reasons for equipment mechanical pressure reducing valve leakage and solenoid valve damage, which are relatively easy to identify and repair.
3. Common faults in liquid pressurization systems
(a) The peristaltic pump is damaged.
(b) The liquid pressure sensor is damaged. Its principle is basically the same as that of a gas pressure sensor.
(c) The internal circuit of the equipment is damaged.
4. Common faults of electrocoagulation and resection systems
(a) Equipment accessories are damaged. Commonly used vulnerable accessories such as foot switches, negative plate wires, connecting wires, etc.
(b) Electrocution, electrocoagulation, and bipolar failure. Inside the device, these parts are composed of different circuit modules. We can repair or replace the corresponding module circuit according to the fault phenomenon.
5. Common faults of power and ablation systems
(a) The power system is mainly caused by the wear of the planing head and the high-energy motor in the planing handle. The replacement of the motor is selective, and not every type of motor has replacement parts. Therefore, special attention should be paid to protection during disinfection and use.
(b) The main loss of the ablation system in surgical applications is the blade. Equipment faults are mostly circuit faults, usually starting from the output part.
6. Common faults of flushing and suction systems
(a) Insufficient pressure or suction. The two-way pump in the equipment is aging, or the negative pressure bottle is leaking.
(b) If the equipment cannot be turned on, it is usually caused by liquid entering the equipment. It is enough to clean up the mistakenly sucked liquid without burning out the relevant parts. In order to minimize the occurrence of equipment failures, a dedicated operating room for laparoscopy should be set up to reduce the movement and damage of instruments, and specialist laparoscopic nurses should be assigned to use and maintain them. The specialist laparoscopic nurses should be fully familiar with the performance and structural characteristics of the instruments and their correct How to use it, strictly implement the operating procedures, and pay attention to the three links of pre-operative inspection, intra-operative troubleshooting, and timely postoperative maintenance. If there is a problem with the equipment, the first step is to carry out emergency repairs, because this can solve the small and medium-sized faults that account for about 85% of the faults.
7. Image display failure
Image display failures mainly include abnormal image display and no image on the monitor.
(a) Abnormal image display failure phenomenon is that the monitor has image output, but the image has horizontal or vertical color stripe interference, color snowflake-like flickering, etc. The fault analysis and processing are as follows:
First, check the connection point between the HD camera handle and the cable. Repeated bending and pulling of this connection point during use can easily cause damage to the cable, and horizontal or vertical color stripes will appear on the image. The solution is to replace the connection cable. Secondly, the plug connecting the cable to the host is prone to aging and corrosion after repeated plugging and unplugging or improper operation, resulting in poor contact and image failure. The countermeasure is to strengthen standardized operation training and regular maintenance. Due to the increasing number of electrified equipment in the operating room, especially the application of high-frequency and high-current equipment such as electrosurgical devices, small signal interference may occur. Especially when equipment such as electrocoagulation rods, electrosurgical pens or connecting cables have leakage, every time the foot switch is used to start electrocoagulation or electrocution, the display image will completely turn into colorful snowflakes and flash. After releasing the foot pedal to stop the output, The image returns to normal. In situations like this, it is necessary to immediately replace a set of intact electrosurgical equipment to ensure that the operation is successfully completed. At the same time, detect leakage of electrocoagulation rods, electrosurgical pens, connecting wires and other equipment, and repair or replace them in time.
(b) The phenomenon of monitor no image failure is mainly that the monitor has no image output, which can be divided into two types: one is the monitor is in a black screen state with no image,
There is no endoscopic field of view frame; the other is a monitor with an endoscopic field of view frame, but no image. 1. For the first fault phenomenon, it is generally considered whether it is caused by a fault in the monitor itself or a fault in the signal input. Most of today's monitors are high-definition LCD displays. When checking the monitor, you need to measure whether the external 12 V DC power adapter is supplying power normally. If there is no normal power supply, replace the adapter in time; if it is normal, restart the device and observe the power-on self-test screen. Is it normal? If the self-test fails, it can be sent to a professional agent for repair. Today's medical high-definition LCD monitors have mature technology, reliable quality, and generally have very low failure rates. Most of the failures that cause no image phenomenon are caused by signal input failures. At this time, you should start with the simplest operation. First check whether the signal input mode of the LCD monitor is set correctly. Common signal input modes include DVI, HDMI, S-Video, SDI and other formats. Then check the type of signal transmission cable and its connection with the monitor. Determine the input mode by the type name of the access port on the monitor. Check whether the signal format in the input menu of the monitor is set to the same. If it is different, most of the faults can be eliminated after resetting. On the contrary, you need to check in the opposite direction along the signal transmission path to see whether the signal transmission cable between the camera host and the monitor is detached or damaged, and check whether the camera host and camera are working properly. If the above equipment fails, it needs to be replaced in time. parts and professional repairs. 2. Regarding the second fault phenomenon, the priority should be given to problems with the endoscope mirror itself. For example, various electronic soft mirrors leak and liquid enters the CCD, causing corrosion of the CDD base, severe damage to the CCD, and no image output. When the hard lens is bent, deformed, or the objective lens is broken, it will also cause no image failure. These problems are mainly caused by irregular operations during diagnosis, surgical treatment, and sterilization. For example, when using holmium laser in urological surgery, the optical fiber was not operated in place and the mirror pipeline was broken down; the hard lens objective was shocked by the high-frequency electrosurgical knife or accidentally hit by the working part of the power system, causing the objective lens to break; or the objective lens was sterilized and sterilized. Damage caused by accidentally dropping and bumping when using bacteria. Due to the limitations of its own maintenance technology and equipment, most endoscopes with the above faults need to be sent out to professional maintenance companies, which is time-consuming and expensive. Therefore, it is necessary to standardize operations, and operators must undergo strict training and assessment on a regular basis to reduce the occurrence of such failures.
8. Endoscope failure
Endoscope failures are mainly divided into two categories: rigid tube endoscope failures and electronic flexible endoscope failures. Due to its structure and usage characteristics, the failure phenomenon of rigid tube endoscopes is mainly manifested by changes in image properties, such as dim images, blurred images, incomplete images, and some obvious deformations and defects of the scope due to external factors; electronic soft endoscopes The main faults include water leakage, water vapor blockage, empty corner buttons and insufficient bending angle, dark images, etc.
(a) Rigid endoscope failure
Fault phenomena include dim images, blurred images, incomplete images, obvious deformation and defects of the mirror due to external factors, etc. The fault analysis and treatment measures are as follows: 1. The image is dim. First check whether the cold light source and optical fiber are normal. If the cold light source bulb accumulates The usage time has reached 500 hours. If the optical fiber is obviously broken or has obvious dark spots, it should be replaced in time. When there is no problem with the above two components, it is mostly because the endoscope beam guide connector is contaminated and turns black and yellow. The solution is to clean the endoscope image transmission system. 2. The image is blurred. In most cases, it is due to long-term use. It is caused by the wear and aging of the protective glass, and sometimes the sealing damage of the objective lens. Regular maintenance can effectively prevent failures. 3. Incomplete image. Most of this failure is caused by the breakage or chipping of the cylindrical lens inside the endoscope, and artificial falls and impacts are the main causes of this damage. The use, transportation, and During disinfection and other processes, it is necessary to handle it with care and take protective measures. 4. The lens body is obviously deformed or damaged due to external force factors. This kind of fault is relatively serious, and generally the above three faults will occur concurrently, or even cause no image output. The main reasons are: Operators accidentally damage the objective lens when using holmium laser, high-frequency electrosurgery, power system and other equipment, causing front-end defects; the operating mirror is misaligned when connecting to the sheath, and then when adjusting the field of view or plugging and unplugging Excessive force may cause deformation; accidental impact or fall during disinfection and sterilization may also cause it. Therefore, strengthening standardized training of operators can reduce the occurrence of failures.
(b) Electronic soft mirror failure Failure symptoms include water leakage, water vapor blockage, empty corner buttons and insufficient bending angle, dark images, etc. Failure analysis and treatment are as follows: 1. Water leakage. The most common failure of electronic soft mirrors is water leakage. Leakage points can appear in many places: pinhole leakage due to aging, scratches, punctures and other damage to the bent rubber; water leakage to the insertion tube due to aging, scratches and other damage; clamp tube tube Wear, puncture and leakage; the sealing ring at the angle knob is aging and leaking; the button is aging, damaged and leaking, etc. The simplest and most effective response and treatment method is to do a good job of leak detection, so that the leakage fault and leaking location can be discovered in time, the mirror should be deactivated and repaired immediately to avoid further expansion of the fault. 2. Water vapor blockage. Water vapor blockage failure occurs from time to time, especially in colonoscopy. Most of the time it is caused by the water and gas nozzle at the tip being clogged with dirt. Use the correct method to remove the nozzle, cut the slender X-ray film, and pull the X-ray film through the nozzle several times to remove the dirt inside. Sometimes you also need to use a water gun or air gun. Flush the gas and water lines several times. 3. The corner button is in a false position and the bending angle is insufficient. Because of long-term use, the angle steel wire will age and become loose, and the pulling position will change. When adjusting the angle, there will be no angle change when the angle button is rotated at the beginning, resulting in a false position and insufficient bending angle. Irregular operation is an important reason for this type of failure. For example, when adjusting the angle, the force is too strong and too fast or the angle is still forcibly adjusted after reaching the limit. In severe cases, the wire may be disconnected. Regular standardized operation training for operators and maintenance of mirrors are important preventive measures. 4. The image is dark. Check the brightness of the cold light source, the condition of the endoscope beam guide, and the monitor brightness and contrast settings. The lamp needs to be replaced in time when it has reached the cumulative use time and the guide beam has aged or broken. There is no need to change the monitor brightness and contrast after they have been set.
(c) Other common ancillary equipment and instrument failures 1. Insufflation machine failures are mainly caused by incorrect pressure and incorrect flow alarms. The former is caused by the failure of the high and low pressure valves inside the equipment. After replacing the pressure sensor or replacing the oil-contaminated diaphragm pad, It can be solved; the latter is caused by the deviation or damage of the gas flow sensor, which can be solved by calibrating the deviation flow sensor or replacing it with a new one. 2. Power system failure is mainly caused by insufficient output power or no output failure. Most of them are caused by aging and wear of the motor and transmission bearings in the power handle or damage to the handle cable. Proper protection during sterilization and regular maintenance can Prevent such failures from occurring.
8. High-frequency electrosurgical faults mainly include no response of the foot switch, disconnection of the connecting wire, leakage of the electrosurgical device, etc. Regular maintenance and inspection can reduce the occurrence of such faults.
With the continuous development of the medical industry, endoscopic equipment systems are becoming more and more popular, and their importance is self-evident. Engineers are managers and maintainers of equipment, so they must work hard to learn the basic principles of endoscopic equipment, carefully analyze various faults, and then solve faults quickly and accurately to ensure smooth diagnosis and treatment in clinical departments.
