Infusion is one of the commonly used clinical treatment methods. Drugs, electrolytes, blood, etc. enter the human body through specific pathways to ensure that the drugs can be absorbed directly. The most common clinical method is intravenous infusion. Depending on the drug, the speed of administration also varies. Even the speed of intravenous infusion is also different.
In order to accurately control the infusion speed during intravenous infusion,
infusion pumps are generally used clinically. As an intelligent infusion device, it can control the delivery speed of drugs to ensure optimal delivery speed.
The infusion pump system is mainly composed of a microcomputer system, a pump device, a monitoring device, an alarm device, and an input and display device. The microcomputer system manages the entire infusion pump, and a single-chip microcomputer system is often used. The pump device is generally a finger-shaped peristaltic pump. A stepper motor drives the roller to rotate, causing a certain part of the infusion pump pipeline to be squeezed, causing peristalsis, thereby pushing the liquid to flow forward. In order to ensure the accuracy and safety of infusion, the infusion pump will be equipped with pressure sensors, bubble sensors, and drop number sensors, which can detect blockage, whether there are bubbles in the tube, and the flow rate of the liquid. When using an infusion pump, if the battery is under-voltage or the pump door is not closed tightly, the alarm system will issue an alarm by acquiring the signal from the sensor. The input display device is used to set parameters and display the operating status of the machine.
The infusion pump is a very useful medical device that can effectively control the delivery speed and pressure of drugs to ensure that patients receive the correct dose of drugs, improve the patient's therapeutic effect, reduce the patient's pain, and improve the patient's quality of life.
The principle of infusion pump
The infusion pump system mainly consists of a control system, a pump device, a sensor device, an alarm device, and an input and display device. The infusion pump control system is the "brain" of the entire system. It intelligently controls and manages the entire system and processes detection signals. It generally uses a single-chip microcomputer system. The pump device is the "heart" of the entire system and the power source for transporting liquids. Our infusion pump uses a semi-squeezed finger-shaped peristaltic pump as the power source. The semi-squeeze finger peristaltic pump uses the rotation of the motor to drive the cam to rotate through the transmission system, so that the valve blades, squeeze blades, and compensation blades circulate back and forth according to specified rules, squeezing the infusion tube, and extruding the liquid in the tube. Compared with the traditional full squeeze method, this extrusion method greatly reduces the damage to the pipeline, reduces the infusion pulsation, and ensures the accuracy of the infusion. The sensor device mainly consists of a variety of sensors, such as pressure sensors, position sensors, and bubble sensors, which are respectively used to detect the clogging pressure of the liquid in the pipe, the door opening and closing status, and the detection of bubbles. The alarm system is a system in which the signal sensed by the sensor is processed by a microcomputer and then an alarm control signal is issued, and then the alarm device responds to remind the user. It has photoelectric alarm and audible alarm functions to alarm for abnormal situations such as power outage, door opening and closing status, infusion completion, battery failure, pipeline obstruction, bubble alarm and other abnormal situations during the infusion process. The input part of the input and display device is responsible for setting various parameters of infusion, such as infusion volume and infusion speed. The display part is responsible for displaying various parameters and current working status.
Classification of infusion pumps
At present, there are various product models of infusion pumps with different performances. According to their working characteristics, they can be divided into three categories: peristaltic control infusion pumps, constant volume control infusion pumps and syringe microinjection infusion pumps.
main feature
1. Small size, easy to operate, saving manpower
2. Accurate dosage, micro-amount, continuous and timed control of dosage. Equipped with a controller, the dripping volume per hour can be controlled between 0.1~2000ml.
3. Avoid side effects caused by drug concentration fluctuations
4. There is a battery inside the pump to ensure continuous medication when the AC power is interrupted.
5. It has obvious advantages in rescuing critical cases and reducing the labor intensity of nursing work.
Main types
Fixed point pumps and non-fixed point pumps
Extracorporeal and implantable pumps
Mechanical pumps and electronic pumps (bolus syringe infusion pump & peristaltic infusion pump)
How to operate
1. Prepare the medicinal solution in the treatment room according to the doctor's instructions, check the quality of the medicinal solution, deterioration, discoloration, turbidity, looseness of the bottle mouth, and expiration date. If correct, saw it open, disinfect Andover cotton swabs, aspirate the medicinal solution, and perform aseptic operations. Add medicine in principle and mix well. Write the name, bed number, name of the added medicine, and dosage on the label on the bottle. Ask a second person to check and help the patient assume a comfortable lying position.
2. Adjust the infusion speed and scheduled infusion volume according to the doctor’s instructions (press ‘Select’ on the infusion pump panel to adjust).
3. Tie the tourniquet, select the blood vessel correctly, loosen the tourniquet, disinfect the skin with Andover, wait until dry, prepare the infusion patch, tie the tourniquet, disinfect the skin with Andover again, puncture and fix it correctly (same as infusion) operating procedures).
4. Record the drugs, liquid volume, and infusion speed in the infusion pump
Common troubleshooting
1. Bubble alarm
reason:
a. There are bubbles in the infusion tube.
b. The infusion tube at the bubble probe is not stuck in place, and there is a gap between the pipeline and the bubble probe.
c. There is dirt on the surface of the bubble probe or dust on the wall of the infusion tube.
d. The tube wall becomes flat after continuous infusion for several hours.
e. The bubble alarm level is set too low.
Troubleshooting steps:
a. Open the pump door, remove the gas in the tube, and restart the infusion pump.
b. Reinstall the infusion tube so that it is completely inserted into the bottom of the bubble probe.
c. Gently wipe off the dirt on the bubble probe with non-drip wet gauze, or wipe the wall of the infusion tube with an alcohol cotton ball.
d. Move the stuck position of the infusion tube up and down slightly.
e. It is recommended to set the bubble gear to level 3 or 4.
2. Blockage alarm
reason:
a. The infusion line is blocked.
b. The blocking pressure level is too low.
Troubleshooting steps: a. Release the pressure in the pipe and eliminate the blockage in the pipe.
b. Reset the blocking pressure level.
3. Forgotten operation alarm
Reason: The infusion pump was not operated within 3 minutes after turning on the machine.
Troubleshooting steps: Continue with subsequent steps.
4. Alarm for low battery power
Cause: The battery is running out of power.
Troubleshooting steps: Charge the infusion pump in time.
5. Alarm when infusion ends
reason:
a. After the dose is input, it will automatically switch to the KVO function.
b When the cumulative volume reaches 9999.9ml, it will automatically switch to the KVO function.
Troubleshooting steps:
You can exit the KVO function by pressing the "Infusion/Stop" key, "Menu/Exit" key, or "Clear" key.
.6. Alarm when door opens abnormally
Reason: The pump door was opened abnormally during the infusion process.
Troubleshooting steps: Check whether the infusion tube is offset from the tube slot, and then re-close and lock the infusion pump door.
7. Incorrect infusion
reason:
a The system did not select the appropriate infusion set.
b The machine is not calibrated.
c The position of the infusion line has not been changed for a long time.
d The temperature is too low and the physical properties of the infusion tube change (such as hardening).
Troubleshooting steps:
a The system selects the matching infusion set.
b Calibrate the machine according to the corresponding pipeline.
c Change the infusion position (recommended to change it every 8 hours).
d Raise the room temperature.
maintenance
1. In order to extend the service life of the infusion pump and maintain the stability of its infusion, please follow the following precautions:
1. Prevent any solid particles from entering the infusion pump body, because dust or any other impurities will wear the plunger, sealing ring, cylinder and one-way valve, so any solid particles in the mobile phase should be removed in advance. The mobile phase is best distilled in a glass container, and the common method is filtration, which can use filters such as Millipore membrane (0.2um or 0.45um). The inlet of the pump should be connected to a sand filter rod (or piece), and the filter of the infusion pump should be replaced frequently.
2. The mobile phase should not contain any corrosive substances, and the mobile phase containing buffer should not be retained in the pump, especially if the pump is stopped overnight or longer. If the mobile phase containing buffer is left in the pump, tiny crystals of salt may precipitate due to evaporation or leakage, or even just due to the stasis of the solution. These crystals will damage the sealing ring and plunger in the same way as the solid particles mentioned above. Therefore, pure water must be pumped in for thorough cleaning, and then replaced with a solvent suitable for column storage and pump maintenance (for reversed-phase bonded stationary phase, it can be methanol or methanol and water).
3. When the infusion pump is working, be careful to prevent the mobile phase in the solvent bottle from running out. Otherwise, running the empty pump will also wear the plunger, sealing ring or cylinder, eventually causing leakage.
4. The working pressure of the infusion pump should not exceed the specified maximum pressure, otherwise the high-pressure sealing ring will be deformed and leakage will occur.
5. The mobile phase should be degassed first to avoid generating bubbles in the pump and affecting the stability of the flow. If there are a large number of bubbles, the pump will not work.
2. If the infusion pump fails, the cause must be identified and corresponding measures must be taken to eliminate the failure:
1. There is no mobile phase flowing out and no pressure indication. The reason may be that there is a large amount of gas in the infusion pump. At this time, the pressure relief valve can be opened to run the pump at a larger flow rate (5ml/min) to drain out the air bubbles. You can also use a 50ml syringe at the pump outlet to help. Extract the gas. Another reason may be that the sealing ring is worn and needs to be replaced.
2. The pressure flow is unstable. The reason may be air bubbles that need to be eliminated, or there may be foreign matter in the one-way valve. You can remove the one-way valve, immerse it in acetone, and perform ultrasonic cleaning. Sometimes there may be bubbles in the sand filter rod or it may be partially blocked by tiny crystal grains of salt or breeding microorganisms. At this time, remove the sand filter rod and immerse it in the mobile phase, remove the bubbles by ultrasonic, or immerse the sand filter rod (piece) Quickly remove microorganisms or dissolve salt in dilute acid (such as 4mol/L nitric acid), and then clean immediately.
3. The reason for excessive pressure is that the pipeline is blocked and needs to be cleared or cleaned. The reason for the pressure drop may be a leak in the pipeline. You can do this section by section when checking for blockages or leaks.
Reason for alarm
The infusion pump alarm system has 6 flashing symbols to facilitate timely response. Door mechanism infusion pump
①AIR flashes, there is air in the infusion tube, take out the infusion tube and re-air it during treatment.
②DOOR flashes, indicating that the infusion pump door is open. Keep pump door closed and locked during disposal.
③DCCL flashes, indicating that the pipeline is blocked. Check whether the pipeline is folded, the rolling clamp is closed, or the needle is blocked.
④LOWBATT flashes, indicating that the battery of the infusion pump is low. At this time, connect the AC power immediately.
⑤EMPTY flashes, indicating that the liquid bottle or bag is empty and the liquid needs to be replaced or the infusion needs to be stopped.
⑥DRIP flow rate 1 is flashing, the drop number sensor is faulty? The sensor is installed incorrectly? The drop number chamber is damaged? The sensor surface is contaminated? Direct sunlight or strong light. DRIP flow rates 2 and 3 are flashing. The setting of the infusion set is inconsistent with the actual setting. Reset it so that the set value matches the actual infusion set used. DRIP4 and 5 are flashing, the wrong infusion set is used or the setting of the infusion set is incorrect. DRIP flow rate 6 flashes, indicating that the infusion set is leaking and the wrong infusion set is used. When the infusion pump stops working, the drop number sensor detects a drip flow of more than 10 drops.
preservation method
When operating the infusion pump, do not touch the power plug with wet hands, and do not use it under direct sunlight or strong light. The sensor plug must be plugged tightly during use, otherwise it will not work properly. When not in use, place it on the seat on the top of the infusion pump to lock it to avoid damage during moving and storage. When charging, turn off the power switch first and then charge. If you are using it for the first time or reusing it after a long period of non-use, fully charge the battery before starting to use it. This infusion pump is prohibited to be stored in a place where it is directly blown by cold and humid (hot) airflow such as fans, air conditioners, electric furnaces, heaters, humidifiers, etc.
development trend
(A) The function will be more comprehensive: it can not only intravenously administer drugs, but also blood transfusions, enteral nutrition solutions, etc.;
(B) Consumables will be cheaper: There is no need to use a special pressure infusion set as consumables, an ordinary gravity infusion set will be more convenient and cheaper;
(C) Safety issues are more prominent: using ordinary gravity infusion sets is particularly prone to confusion of consumables, resulting in accuracy errors and other risks;
(D) The scope of use will be wider: After solving the problem of cheapness and safety of consumables at the same time, all bedside infusions will use infusion pumps, and the dosage will explode;
(E) Supervision will be stricter: With the increase in the number of uses and the diversification of consumables, a large number of medical accidents and medical risks will occur during the use of
infusion pumps, and relevant national agencies will face a more severe regulatory situation, regulations and measures. will be more severe.
