광학 센서를 이용한 비관혈적 혈압 측정의 오차 보정 = Compensation of Error in Noninvasive Blood Pressure Measurement System Using Optical Sensor

다국어 초록 (Multilingual Abstract)

This study is attempted to correct an error of electronic blood pressure meter with an optical sensor. In general, for a hospitalized patient, ECG, blood pressure, oxygen saturation, and respiration are basically measured to monitor the patient's condition. Opening of a blood vessel after it is occluded by pressurizing the cuff influences the blood flow of peripheral blood vessels as well as oscillation changes in the cuff. Blood vessels are occluded and peripheral blood flow disappears at cuff pressure above the examinee's blood pressure, while blood vessels are opened and peripheral blood flow appears again at cuff pressure under the examinee's blood pressure. Then Disappear-Appear Point Length(DAPL) of peripheral blood flow can be judged with the signal of peripheral blood flow, thus is available as a factor of error correction for electronic blood pressure meter. Also, systolic or diastolic blood pressure can be corrected with Appear-Point-Pressure(APP) of cuff pressure at a point where blood flow occurs and Appear-Maximum Pressure(AMP) of cuff pressure at the maximum amplitude point of peripheral blood flow after peripheral blood flow appears again. For verification, 27 examinees were selected, and their blood value was obtained through experimental procedure of 4 stages including induction of blood pressure change. The examinees were divided into two groups of experimental group and control group, regression analysis was conducted for experimental group, and correction of a blood pressure error was verified with optical signal by applying the regression equation calculated in experimental group to control group. As an experimental result, mean of the whole measurement errors was 5mmHg or more, which did not meet the standard fur blood pressure meter. As a result of correcting blood pressure measurements with data of DAPL, APP, and AMP as drawn out of PPG signal, systolic blood pressure, mean blood pressure, and diastolic blood pressure were $-0.6{\pm}4.4mmHg,\;-1.0{\pm}3.9mmHg$ and $-1.3{\pm}5.4mmHg$, respectively, indicating that mean of the whole measurement errors was greatly improved, and standard deviation was decreased.

참고문헌 (Reference)

1 Baker DP, "Theoretical analysis of non-invasive oscillometric amplitude algorithm for estimating mean blood pressure" 35 : 271-278, 1997.

2 Robin P Smith, "Pulse transit time: an appraisal of potential clinical applications" 54 : 452-457, 1999.

3 H. W. Lee, "Estimation of non invasive blood pressure using peripheral plethysmography" Dept of Biomed. Eng., Graduate School 2003

4 Meir Nitzan, "Effects of external pressure on arteries distal to the cuff during sphygmomanometry" 52 (52): 1120-1127, 2005.06

5 O’Brien E, "Comparative accuracy of six ambulatory devices according to blood pressure levels" 11 : 673-675, 1993.

6 W. R. Lee, "Clinical cardiology" Korea Medical Publishing com- pany 2002-, 2002

7 Amoore JN, "Can simulators evaluate systematic differences between oscillometric non-invasive blood pressure monitors" 5 : 81-89, 2000.

8 American National Standard, "American National Standard, ANSI/AAMI SP10:2002 & ANSI/ AAMI SP10:2002/A1:2003 P20-21" 2002