Auscl-D: a mercury-free digital auscultatory sphygmomanometer

More than quarter of world's population is consumed by hypertension, leading to premature death of thousands of people per year across the globe. One of the major reasons behind hypertension misdiagnosis is inaccurate blood pressure (BP) measurements, which can be attributed to various human or instrumentation errors. Currently used BP measuring sphygmomanometers, suffers from poor reliability, performance deterioration over time or are unable to meet environmental protection protocols. In this article, we propose a low-cost, highly portable, light-weight, easily manufacturable, battery operated, mercury free, auscultation based digital sphygmomanometer - Auscl-D, for easy and accurate BP measurements. The proposed device can be made from easily available components with cheap manufacturing processes available throughout globe, even in remote areas. The device demonstrated to have accuracy comparable to mercury sphygmomanometer, which is the gold-standard for BP measurements. The preliminary clinical trials were conducted at Dayanand Medical College & Hospital (DMCH) (Ludhiana, India), to compare the performance of proposed device with commonly used aneroid sphygmomanometers employing the auscultatory method and validated oscillometric sphygmomanometers from MicroLife. The test results show good agreement for systolic and diastolic BP measurements taken using Auscl-D device compared to the aneroid and oscillometric types. This shows the potential of proposed design to serve as low-cost, highly portable replacement for conventionally used sphygmomanometers, without the toxicity and reliability issues.