Automated tesing of infusion devices

Abstract

The aim of this research is to develop a system capable of automatically measuring the critical operating parameters of infusion devices and analysing the test results. Such a system should simply indicate to the user that the device being tested has either passed or failed, or that, based on previously stored data, one or more of the measured parameters has changed significantly since the last test(s).
Measurement and monitoring of critical operating parameters would provide an early indication of deterioration in performance and verify that a device still meets the criteria for its designated risk category. Efficiency would be improved by eliminating user intervention both in performing tests and analysing the data.
Commonly used techniques and systems for testing infusion devices are compared with the procedures used by the Medical Engineering Department at the Preston Acute Hospitals. Recommended test procedures specified in the American National Standard and the Draft British Standard for Infusion Devices are also investigated.
The development of a test system based on the gravimetric technique is described. The system is designed to facilitate frilly automated testing. Databases allow the specifications of individual models of infusion devices and complete test sequences to be stored. The technique is further improved by the development of additional hardware to control priming of the system, emptying of the weighing vessel and occlusion of the administration line.
Comprehensive tests performed on a total of forty five infusion devices indicate that such a system can be used successfully within a typical Medical Engineering Department. Each model of infusion device was shown to generate a unique flow rate
curve, which remained consistent. It was also shown that trumpet curve analysis provides the best means of quantif'ing short-term flow rate. A reduction in the sampling interval does not significantly affect quantitative measures of the short-term
flow rate but is necessary to automatically detect expected changes in the parameters being measured.