Infusion pump
An infusion pump is a metering pump for the continuous (predominantly intravenous ) administration of infusions . In clinical practice, the term Infusomat (brand name of B. Braun Melsungen AG ) is often used synonymously.
The pumping principle of the pumps is largely based on the system of slide peristalsis , with which a uniform flow with low pulsation and variable strength can be generated. One revolution of the shaft of the peristalsis corresponds to a work step in which a certain amount of infusion solution is supplied to the infusion system by compressing a defined volume of tubing . Hence the name volume-controlled or volumetric pump.
Additional volume control is sometimes provided by an automatic dropper on the air trap on the supply bottle. However, since the viscosity and the drop volume vary with the infusion solution used, the actual volume flow can only be determined imprecisely. The system is only used in old devices or to monitor the level of the storage container. Current volumetric pumps can thus achieve an infusion rate in the range from 1 to a maximum of 1000 ml / h with a maximum accuracy of ± 5%.
Patient safety
The slide peristalsis is not part of the infusion system and therefore does not come into direct contact with the infusion solution. Disposable material can be used without having to sterilize the pump separately. Other pump systems such as diaphragm or piston pumps have prevailed primarily in portable systems. In addition to the drop sensor, further safety features include a flow blocker that prevents uncontrolled infusion when the pump door is opened, and an air sensor that switches the pump off when the access is ventilated.
When infusing via a central venous catheter , the infusion pump prevents the infusion solution from being drawn in by negative central venous pressure . Infusion pumps are therefore often used in intensive care medicine .
See also
Web links
Individual evidence
- ↑ Hutten, Helmut (Ed.): Biomedical Engineering Volume 2 . Springer, Berlin Heidelberg 1992, ISBN 3-5405-2538-6 .
- ^ Haufe, Gunter (and others): Medical technology in intensive care medicine . Prof. Dr.-Ing. Wilfried J. Bartz, expert verlag, Renningen-Malmsheim 1998, ISBN 3-8169-1519-1 , p. 175ff.
- ↑ RS Khandpur: Handbook of Biomedical Instrumentation . McGraw-Hill Professional, 2003, ISBN 978-0070473553 , p. 870.
- ^ Haufe, p. 175