Introduction of an electronic aneroid sphygmomanometer that could meet both professional and unprofessional demands

Abstract

To the Editor: It is very important to get the accurate blood pressure of the patients for the diagnostic purpose. Among the routine physical checks done by the people themselves, the monitoring of the blood pressure is also an essential item. Though the devices for blood pressure monitoring are very common, but there are many differences among them. The usually three different types of blood pressure monitors are the mercury sphygmomanometer (MSM), the aneroid gauge and the oscillometric automated electronic blood pressure monitors (OABP) [5]. The doctors and nurses usually take the MSM as reliable devices for blood pressure measurement. The principle adopted by the doctors while using MSM is the Korotkoff-sounds method (KSM) which has been approved by professional medical practices over 100 years. The KSM is accepted as the practical gold standard to measure blood pressure [2]. But the mercury in the MSM has potential threaten to health and environment. The aneroid gauge was used as sphygmomanometer long time ago and not welcomed now. The often and troublesome calibration is necessary to keep its accuracy because of the mechanical structures. The OABP is mainly used for routine health check mainly even in hospitals because of its convenience. The OABP is also popular for nonprofessional users who want to monitor their blood pressure at home. It is handy, and easy to operate for those people who perform a daily self-examination. The famous professional societies, such as the Association for the Advancement of Medical Instrumentation (AAMI), the European Society of Hypertension (ESH), and the British Society of Hypertension (BSH), have made some protocols to validate the OABP [4, 6]. However, the OABP cannot be applied to those patients suffered arrhythmias, pre-eclampsia, and certain vascular diseases even if they are qualified models according to the international protocol [3]. It would be very helpful to develop a kind of device which is as accurate as the MSM and as convenient as the OABP. The efforts to produce this kind of devices in order to be used in hospital without limitation were proposed [8]. The gold standard KSM was taken in the reported device and the Korotkoffsounds signals were analyzed by digital signal processing techniques. The author claimed that the blood pressure could be measured accurately but only in laboratory not in clinical practice. A joint time–frequency analysis (JTFA) technique was reported as an algorithm to characterize the different phases of the Korotkoff-sounds by Allen et al. [1]. The JTFA is very useful to identify the first phase and the fifth phase of the Korotkoff-sounds, which are the two key points to mark the systolic and diastolic blood pressure in KSM. But the work of Allen was only in theory. A model of electronic sphygmomanometer characterizing with accuracy and equivalence to the MSM, mainly for the professional operators, was reported recently [7]. Our team built the multipurpose electronic sphygmomanometer (MESM) which combined the advantages of both the MSM and the OABP. The principle of the MESM is the KSM. While the MESM is used for diagnostic purposes, it keeps the involvement of the professional operators. The professional operators could judge the results of the blood pressure conveniently according to the Korotkoff-sounds loud speakers. This is very important for doctors while they measure the blood pressure of some patients who are suffering some vascular diseases, where the OABP could not be used. Another advantage is that the device could relieve the doctors of the ear-pain with the louder-speaker instead of the X. Xin W. Chen (&) Biomedical Engineering School of the Southern Medical University, Guangzhou city, China e-mail: xxg@fimmu.com