Non Electronic Blood Pressure Assist Device
Hutton, E; Tsoi, A H; Ashiru-Balogun, J; Narine, M; Hinkle, J; Hadjiargyrou, M; Liu, J; Strey, H
Department of Biomedical Engineering, Stony Brook University, Stony Brook, New York
Cardiovascular disease (CVD) is responsible for 30% of global deaths and unfortunately, 50% of these deaths can be prevented . However, compared to industrialized countries, developing nations do not have readily available methods for accurate diagnosis of CVD. Engineering World Health (EWH) , a nonprofit organization with headquarters at Duke University, seeks to improve the availability of healthcare in these countries by working directly with clinicians and technicians to determine the most urgent needs. One such example is a device for blood pressure measurements without the use of a stethoscope and with minimal training, or a “Non Electronic Blood Pressure Assist Device”.
CVD has many risk factors, one of which is hypertension. Unreliable power supplies and few trained professionals dictate the necessity of a non-electronic device that will eliminate the need to train individuals to identify Korotkoff sounds (heart sounds) using a stethoscope. With increased availability of blood pressure readings, treatment options can be identified earlier to help prolong a hypertensive patient’s life.
We have implemented a dual membrane design, inspired by the phonendoscope. The lower membrane is a stethoscope diaphragm and the upper is a flexible plastic made of low density polyethylene (LDPE). Both are sealed perpendicularly to a rigid, transparent, plastic frame that extends above the upper diaphragm, a viewing window encasing particles. The diaphragm will be placed above the brachial artery to detect a pulse. Thus, a vibratory pulse will be amplified by both diaphragms and induce particle movement, causing refraction effects visible to the naked eye in a well lit area. This effectively transduces the mechanical Korotkoff signal to a visual signal.
In addition to being listed on the “Projects that Matter” list researched and created by EWH , the need to facilitate availability of blood pressure measurement is emphasized by K. Srinath Reddy, MD, DM and Salim Yusuf, Ph.D in their article “Emerging Epidemic of Cardiovascular Disease in Developing Countries” . They assert that blood pressure is a key risk factor for CVD, worthy of monitoring. If we are able to increase the availability of accurate blood pressure readings through the distribution of our device, we expect to have a positive effect on the occurrence of CVD in the developing world.
 United States. American Heart Association. International Cardiovascular Disease Statistic, 2005. <www.americanheart.org...>.
 K. Srinath Reddy, and Salim Yusuf. Emerging Epidemic of Cardiovascular Disease in Developing Countries Circulation 97: 596-601