System structure and working principle of medical infusion pump
The infusion pump is usually a mechanical or electronic control device, which achieves the purpose of controlling the infusion speed by acting on the infusion catheter. It is often used in situations that require strict control of the amount of infusion and the amount of medicine, such as the application of blood pressure drugs, antiarrhythmic drugs, intravenous infusion of infants and young children or intravenous anesthesia.
Infusion pump system
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 is the "brain" of the whole system. It controls and manages the whole system intelligently, and processes the detection signals. Generally, a single-chip microcomputer system is used. For example, the infusion pump adopts a highly integrated 32-bit ARMCPU system to fully control the infusion process, and uses dual CPUs to ensure the safety of the system.
The pump device is the "heart" of the entire system and the power source for liquid delivery. Medical infusion pumps generally use a finger-like peristaltic pump as the power source. Finger-like peristaltic pumps use rollers to rotate to squeeze a certain part of the infusion pump pipeline to produce peristalsis, thereby pushing the liquid forward. Finger-shaped peristaltic pump has the characteristics of small size, light weight, accurate quantitative and convenient infusion tube loading and unloading, and it is the most widely used. This kind of pump has a camshaft, and there are multiple cams on the camshaft. The motion rules of these cams differ by a certain angle, and each cam is connected with a finger-like slider.
When working, the stepping motor drives the camshaft to rotate, so that the slider moves up and down according to a certain sequence and motion law, and sequentially squeezes the intravenous infusion tube like a wave, so that the liquid in the infusion tube flows directionally at a certain speed. The finger-like peristaltic pump is more accurate, and can control the total amount of infusion and the infusion speed in a wide range; when the number of "fingers" exceeds 8 (usually 12), the linearity of the pump is good, and it is not easy to produce pulsation during infusion, which makes the infusion pump The safety and stability monitoring device is mainly composed of a variety of sensors. The infusion pump is equipped with an infrared drop number sensor, a pressure sensor and an ultrasonic bubble sensor, etc., which are used for liquid flow rate and flow, blocking pressure, and leakage and bubbles. Detection.
In the alarm system, the signal sensed by the sensor is processed by a computer to obtain an alarm control signal, which is then responded by the alarm device to attract people's attention and perform correct processing at the same time. With photoelectric alarm and sound alarm function, it can alarm for abnormal situations such as power failure, unclosed pump door, low temperature, completion of infusion, battery undervoltage, pipeline blockage, and bubbles in the pipeline 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.
