Development of software for pulse oximeter and investigation of its realtime response in clinical environment

We developed a pulse oximeter software at Thorax Centre, Erasmus University as a joint project with an industry and evaluated it in the clinical environment of thorax anaesthesia using a computerized protocol for realtime data collection during routine clinical procedures. This paper gives an account of the results we obtained from the development project and the clinical study. The paper consists of two parts. First part describes different components of the software module and their influence on different aspects of the clinical behaviour of the oximeter. The second part describes the results of realtime response investigation. The investigation was carried out using a personal computer to collect the data continuously during anaesthesia, surgery and post-operative periods. Two other industry standard oximeters, Nellcor and Ohmeda were also included in our study. We collected data on more than fifty patients on an average of eight hours per patient over a period of four months with major emphasis on low-saturation occurrences. The interpretation of the data was focused more on the realtime response anomalies on random cases than on ensemble statistical data evaluation. We found, that there are few factors in clinical environment which often influences the measurement of a pulse oximeter very strongly. Most often the anomalies were found during low saturation measurement. The main objective of this paper is to make the results available to practising clinicians so that it may be useful to identify these occurrences during routine clinical usage.