Multi-channel architecture for evaluation of automated oscillometric blood pressure devices

This paper presents an automated system for testing of oscillometric blood pressure devices. The designed and implemented system includes three measurement channels. One of the measurement channels is based on the usage of a miniature pressure sensor and appropriate pneumatic circuit connected to the cuff tube of the tested oscillometric device. The second channel based on EMFIT sensor is used for dynamic mechanical stress measurement during cuff deflation. To obtain the continuous blood pressure variation during the oscillometric device testing, the multichannel architecture includes a Finometer device. Appropriate conditioning circuits connected to the sensing parts deliver the voltages associated with sensing wave turbulence and cuff pressure variations during blood pressure measurement procedure, through a high resolution data acquisition board connected to a computer. Software developed in LabVIEW performs the acquisition and primary processing of the acquired signals as well as data storage. The estimation of blood pressure by oscillometric devices was analyzed in this work taking into account the information on blood pressure changes detected by the Finometer device, the EMFIT sensor and cuff pressure sensor response during measurement, and through auscultatory method. Preliminary results suggest that the designed system may be used for more objective testing of oscillometric blood pressure device accuracy in estimating systolic and diastolic blood pressure.