• Journal of Biomedical Engineering Research
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• v.28 no.2
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• pp.178-186
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• 2007

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.

• Journal of Biomedical Engineering Research
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• v.33 no.3
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• pp.155-162
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• 2012

Devices to measure the blood pressure of patients are being used without any calibration in a hospital. It is an important to show consistent values when any medical devices measure the same patients regardless they are sphygmomanometer or fully automatic electronic blood pressure meter. We compared sphygmomanometer and fully automatic electronic blood pressure meters with standard digital blood pressure monitor (SDBPM) to evaluate the consistency of the small healthy subjects. We measured the blood pressure from six healthy subjects (three of 20~40 years and three of 40~60 years old). Two sphygmomanometer and two fully automatic electronic blood pressure meters were used and compared with the SDBPM. Blood pressures measured from right and left arms each and were compared. All six healthy subjects showed normal blood pressure values. In general, left blood pressure values showed higher values than right side. Comparing SDBPM, with the other monitors, the systolic pressure showed ${\pm}$ 34.8% difference and ${\pm}$ 33.3% for the diastolic pressure. Correlation between SDBPM and Sphygmomanometer was 0.59~0.71, and 0.50~0.70 for fully automated digital BP monitors. It fell in grade-D when we apply the BHS(British hypertension society). AAMI(American association for the advancement of medical instrumentation) also showed unsatisfactory results for the mean value (${\leq}$ 5 mmHg) and standard deviation (${\leq}$ 8 mmHg). We tested sphygmomanometer and fully automatic electronic blood pressure meters and compared with a standard digital blood pressure monitor. All devices showed inconsistent blood pressures. A reliable calibration system is highly needed for all devices in all hospitals.

• Journal of Magnetics
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• v.16 no.4
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• pp.449-452
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• 2011

A wrist wearable cuffless pulsimeter with a portable and small size apparatus using Hall effect is fabricated. The analysis of the pulse wave measured by the testing product of pulsimeter is done to measure the pulse rate and blood pressure. The blood pressure obtained by the puslimeter is compared with the practical values measured by electronic or mercury liquid blood pressure meters. The detail analysis of a pulse wave measured by a wrist wearable cuffless pulsimeter detecting the changes of the magnetic field can be used to develop a new diagnostic algorithm of blood pressure applying for oriental medical apparatus.

• The Journal of the Korea institute of electronic communication sciences
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• v.14 no.6
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• pp.1257-1264
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• 2019

The traditional cuff-based method for BP(Blood Pressure) measurement is not suitable for continuous real-time BP measurement techniques. For this reason, the previous studies estimated various blood pressures by fusion with the electrocardiography (ECG) and photoplethysmogram (PPG) sensor signals. However, conventional techniques based on PPG bio-sensing measurement face many challenging issues such as noisy supply fluctuation, small pulsation, and drifting non-pulsatile. This paper proposed a novel BP estimation methods using PPG and ECG sensors, which can be derived from the relationship between PPG and ECG using PTT(Pulse Transit Time) and PWV(Pulse Wave Velocity). Unlike conventional height ratio features, which are extracted on the basis of the peaks in the PPG and ECG waveform. The proposed method can be reliably obtained even if there are missing peaks among the sensed PPG signal. The increased reliability comes from periodical estimation of the peak-to-peak interval time using ECG and PPG. After 250,000 times trials of the blood pressure measurement, the proposed estimation technique was verified with the accuracy of ±28.5% error, compared to a commercialized BP device.

• Proceedings of the Korean Magnestics Society Conference
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• 2009.12a
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• pp.229-230
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• 2009

• KSBB Journal
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• v.26 no.3
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• pp.211-216
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• 2011

To study the effects of ethanol extract of the Rhodiola Sachalinensis on the anti-oxidation and blood pressure and skeletal muscles contractility in rats. The ethanol extracts and fractions of Rhodiola Sachalinensis were determinated the anti-oxidation effects by DPPH(1,1-dipenyl-2-picrylhydrazyl) method and comparing with the BHA (Butylated hydroxyanisole) and AA(Ascorbic acid). The gastrocnemius and soleus muscle contractility were observed by stimulating the sciatic nerve with electricity after affusing stomach with ethanol extract of the 200 mg/kg dosage of Rhodiola Sachalinensis for 4 weeks. The ethanol extract of the Rhodiola Sachalinensis could shorten latent period, increase maximal contractive extent and time and relaxative time at the twitch and complete tetanus of gastrocnemius and soleus muscles. The ethanol extract of the Rhodiola Sachalinensis shows high anti-oxidation effect and can enhance skeletal muscles contractility in rats.

• Journal of Preventive Medicine and Public Health
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• v.28 no.4 s.51
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• pp.783-794
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• 1995

This study was conducted to clarify the relationship of body fat percent with serum lipid level and blood pressure in adults. The study subjects were 472 men and 189 women who visited Multiphasic Health Screening Center of Yeungnam University Hospital in Taegu from May 20 to September 30, 1994. The relationship of serum lipid and blood pressure with BMI, Katsura index, atherogenic index, which calculated from the health screening data and body fat percent measured by impedance fat meter(model SIF-819) were analyzed. Three groups were classified as Group I (men : body fat Percent $\geq$ 20, women : body fat percent $\geq$ 25), Group II (men : 15 $\leq$ body fat percent< 20, women : 20 $\leq$ body fat percent< 25), Group III(men : body fat percent < 15, women body fat percent <20). In this study, Group I accounted for 3.2% in men, 3.7% in women. Weight was significantly different among three groups in both sexes(p<0.01) and height was not significantly different among three groups. In men, serum total cholesterol, triglyceride, high density lipoprotein, low density lipoprotein, atherogenic index were significantly different(p<0.01). In women, serum total cholesterol and low density lipoprotein were significantly different(p<0.05) but there was no differences in triglyceride and high density lipoprotein among three groups. BMI and Katsura index were significantly different among three groups in both sexes(p<0.01). In men, body fat percent was positively correlated with weight, BMI, Katsura index, total cholesterol, triglyceride, low density lipoprotein, atherogenic index and systolic and diastolic blood pressures, and negatively correlated with high density lipoprotein. In women, body fat percent was positively correlated with age, height, weight, BMI, Katsura index, total cholesterol, triglyceride, low density lipoprotein and atherogenic index, and negatively correlated with high density lipoprotein. But there was no significant correlation between body fat percent and blood pressure in women. In multiple regression analysis for total cholesterol, fat percent, age and BMI were significant independent variables in men$(p<0.05,\;R^2=0.1286)$, and body fat percent and age in women$(p<0.05,\;R^2=0.3399)$. In case of LDL/HDL ratio, only BMI was a significant independent variable in menu$(p<0.01,\;R^2=0.0954)$, and body fat percent, age and BMI in women$(p<0.05,\;R^2=0.3164)$. In multiple regression analysis, age, low density lipoprotein and total cholesterol were significant independent variables on systolic blood pressure in men$(p<0.05,\;R^2=0.1297)$, age and total cholesterol in women$(p<0.05,\;R^2=0.1705)$. On diastolic blood pressure, only age was a significantly independent variable in men$(p<0.01,\;R^2=0.0972)$ and women$(p<0.01,\;R^2=0.1218)$. From the result of this study, it could concluded that body fat percent was significantly associated with other obesity indices and serum lipid, but had no significant association with blood pressure. To establish the relationship of body fat percent with blood pressure, further study which consider other variables that may have an effect on blood pressure should be performed.

• Journal of The Korean Society of Integrative Medicine
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• v.11 no.3
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• pp.127-135
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• 2023

Purpose : This study was performed to evaluate the effects of magnetic therapy (MT) on pain threshold, blood flow, and balance in patients with knee osteoarthritis. Methods : A single-blind, randomized controlled trial (RCT) was conducted with 30 patient with knee osteoarthritis. They were randomly allocated 2 groups; magnetic therapy group (MTG; n=15) and placebo magnetic therapy group (PG; n=15). The MTG group received 30 minutes magnetic therapy and 20 minute conservative physical therapy (Hotpack, ICT), magnetic therapy was conducted in magnetic therapy device (OM-100, NUGA, Korea). In the placebo magnetic group received 30 minutes placebo magnetic therapy and 20 minute conservative physical therapy. Each group performed 50 minutes a day 3 times a week for 8 weeks. The primary outcome pressure pain threshold test, blood flow, balance ability were measured by a pressure threshold meter (Commander algometer, JTECH medical, USA), laser dofler image (Moor LDI2-IR, Moor instruments, USA), balance measurement system (BioRescue, Marseille, France). The measurement were performed before and after the 8 weeks intervention period. Results : Both groups demonstrated significant improvement of outcome in pain threshold, blood flow, and balance ability during intervention period. magnetic therapy group revealed significant differences in pain threshold, blood flow, and balance as compared to the placebo magnetic therapy group groups (p<.05). Our results showed that magnetic therapy was more effective than placebo therapy on pain threshold, blood flow, and balance in patients with knee osteoarthritis. Conclusion : Our findings indicate that magnetic therapy can improve pain threshold, blood flow, and Balance, highlight the benefits of magnetic therapy. This study will be able to be used as an intervention data for recovering pain threshold, blood flow, and balance in patients with knee osteoarthritis.

• Korean Journal of Acupuncture
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• v.28 no.1
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• pp.53-60
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• 2011

Objectives : Cupping therapy has been used as various treatment methods in oriental medicine clinic for a long time. Specially, Cupping stimulation caused skin hyperpigmentation which has been used as diagnosis method for extravasated blood & inner organs functional disease. But it was difficult to quantitatively measure and analyze the interrelation between extravasated blood and skin hyperpigmentation. The aim of this study is to measure the acupoint's RGB and melanin change pattern by stimulating under fixed 80kPa negative pressure and to evaluate the extravasated blood. Methods : To evaluate extravasated blood, 10 acupoints (left/right BL13, BL15, BL18, BL20, BL23) were stimulated by treatment 80kPa negative pressure for 1 minute. And then we measured the acupoints' skin color change patterns using the color meter, followed by RGB analysis and melanin change pattern. Results and Conclusions : We could observe the correlation of the acupoints' skin color condition related with RGB change pattern. All acupoints' color change degree were different. Regardless of acupoints' color degree due to extravasated blood, we observed in common the fact that RGB values decreased after stimulation and steadily increased according to time. We observed that melanin index increased after stimulation and recovered before stimulation-condition after the lapse of time. In other words, we confirmed the correlation between raised color change degree and $L^*a^*$ index change pattern. Therefore we observed the possibility of charting the $L^*a^*$ index following extravasated blood.

• Journal of Yeungnam Medical Science
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• v.10 no.2
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• pp.345-359
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• 1993

This study was conducted to identify the factors related to the blood pressure in school children. The study subjects were 144 boys and 140 girls aged 10 years old, 4th grade student of one elementary school in Taegu City. Blood pressure and 18 variables for 284 school children were measured in May 1992. A weight-for-height index, R$\ddot{o}$hrer index(weight/$height^3$) was calculated for each individual as a measure of obesity. Body fat percent, fat weight, and lean body mass were measured by impedance fat meter(Model SIF-891). Serum total cholesterol, high-density lipoprotein, triglyceride, uric acid, total protein, and electrolyte were measured by automated clinical chemistry analyzer(Hitachi 4020). Low-density lipoprotein and atherogenic index were calculated by the equation. The variables assessed were sex, systolic blood pressure, diastolic blood pressure. R$\ddot{o}$hrer index, body fat percent, body fat weight, lean body mass, total cholesterol, high-density lipoprotein, low-density lipoprotein, uric acid, total protein, serum electrolyte and blood glucose. The mean systolic and diastolic blood pressures for boys were 104.1mmHg and 66.6mmHg and those for girls were 102.9mmHg and 67.5mmHg. Systolic blood pressure of boys was positively correlated with height, weight, R$\ddot{o}$hrer index, fat weight, lean body mass, and triglyceride. Systolic blood pressure of girls was positively correlated with height, weight, lean body mass, and uric acid. Diastolic blood pressure of boys was positively correlated with weight. R$\ddot{o}$hrer index, and lean body mass. Diastolic blood pressure of girls was positively correlated with height, weight, fat weight, and lean body mass and negatively with total serum protein. In multiple regression analysis for the systolic blood pressure, the significant independent variables were R$\ddot{o}$hrer index and serum sodium in boys, and serum uric acid, fat percent, and R$\ddot{o}$hrer index in girls. In multiple regression analysis of the diastolic blood pressure, the significant independent variables were R$\ddot{o}$hrer index in boys and total serum protein in girls. This study indicated that important factors influencing blood pressure in school children were R$\ddot{o}$hrer index, fat percent, serum sodium, uric acid, and total protein. R$\ddot{o}$hrer index was most important among these. It is recommended to enforce the nutritional education for diet control of obesity to prevent hypertention in children and to adopt healthy life-styles that promote good health and prevent development of cardiovascular risk factors.