cuffless differential blood pressure estimation using smart phones
DESCRIPTION
Smart phones today have become increasingly popular with the general public for their diverse functionalities such as navigation, social networking, and multimedia facilities. These phones are equipped with high-end processors, high-resolution cameras, and built-in sensors such as accelerometer, orientationsensor, and light-sensor. According to comScore survey, 26.2% of U.S. adults use smart phones in their daily lives. Motivated by this statistic and the diverse capability of smart phones, we focus on utilizing them for biomedical applications. We present a new application of the smart phone with its built-in camera and microphone replacing the traditional stethoscope and cuff-based measurement technique, to quantify vital signs such as heart rate and blood pressure. We propose two differential blood pressure estimating techniques using the heartbeat and pulse data. The first method uses two smart phoneswhereas the second method replaces one of the phones with a customized external microphone. We estimate the systolic and diastolic pressure in the two techniques by computing the pulse pressure and the stroke volume from the data recorded. By comparing the estimated blood pressure values with those measured using a commercial blood pressure meter, we obtained encouraging results of 95–100% accuracy.TRANSCRIPT
Cuffless Differential Blood Pressure Estimation Using
Smart PhonesVikram Chandrasekaran, Ram Dantu,Srikanth Jonnada,
Shanti Thiyagaraja, and Kalyan Pathapati Subbu
IEEE TRANSACTIONS ON BIOMEDICAL ENGINEERING, VOL. 60, NO. 4, APRIL 2013
Overview
Proposed work
Outline
• Methodology• Internetworking of Components• Mathematical Analysis• Results
Methodology
• Setup of Two Mobiles for Blood Pressure Estimation
• Setup of Single Mobile Phone for Blood Pressure Estimation
Setup of Two Mobiles for Blood Pressure Estimation
Setup of Two Mobiles for Blood Pressure
Estimation(Contd.)
RTT= T’s–Ts
Tt=RTT/2
Ot=Ts-(Tr-Tt)
Setup of Single Mobile Phone for Blood Pressure
Estimation
Outline
• Methodology• Internetworking of
Components• Mathematical Analysis• Results
Internetworking of Components
• Location of Heart Beat
Internetworking of Components• Pulse Detection and Hear Rate
Calculation
Internetworking of Components
• Integration of Components
Identification of Peaks
Outline
• Methodology• Internetworking of
Components• Mathematical Analysis• Results
Mathematical Analysis
• Systolic PressurePs = −0.425×VTT+214
• Pulse Pressure and Stroke volume
Pp =SV/(0.013 × Wt − 0.007 × age −.004× HR) + 1.307
• Diastolic Pressure Pd = Ps − Pp
Outline
• Methodology• Internetworking of
Components• Mathematical Analysis• Results
Results
Limitations
• Video intensity is very native without much filtering
• Device incompatibilities most likely occur
• Requires use of rooted phones• Measurement may not be possible in
public.• subject needs to be sitting up right
with the arm holding the camera in level to the heart.
Future work
• Identifying incorrect holding of phone and instructing a proper way by mobile.
• Real-time filtering of audio heart sounds
• Using more reliable sources.
Conclusion
• Show better performances• Accuracies between 95-100%• Using Smartphones• Well for using in normal and
nonpathological cases.• Not affected by age, height &
weight.
Thank You