• Clinical and Experimental Pediatrics
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• v.65 no.2
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• pp.73-80
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• 2022

A mercury sphygmomanometer (MS) has been the gold standard for pediatric blood pressure (BP) measurements, and diagnosing hypertension is critical. However, because of environmental issues, other alternatives are needed. Noninvasive BP measurement devices are largely divided into auscultatory and oscillometric types. The aneroid sphygmomanometer, the currently used auscultatory method, is inferior to MS in terms of limitations such as validation and regular calibration and difficult to apply to infants, in whom Korotkoff sounds are not audible. The oscillometric method uses an automatic device that eliminates errors caused by human observers and has the advantage of being easy to use; however, owing to its measurement accuracy issues, the development of an international validation protocol for children is important. The hybrid method, which combines the auscultatory and electronic methods, solves some of these problems by eliminating the observer bias of terminal digit preference while maintaining measurement accuracy; however, the auscultatory method remains limited. As the age-related characteristics of the pediatric group are heterogeneous, it is necessary to reconsider the appropriate BP measurement method suitable for this indication. In addition, the mobile application-based BP measurement market is growing rapidly with the development of smartphone applications. Although more research is still needed on their accuracy, many experts expect that mobile application-based BP measurement will effectively reduce medical costs due to increased ease of access and early BP management.

• International journal of advanced smart convergence
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• v.8 no.2
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• pp.227-236
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• 2019

In this study, we develop a Korotkoff sound based automatic blood pressure measurement device including sensor, hardware, and analysis algorithm. PVDF-based sensor pattern was developed to function as a vibration sensor to detect of Korotkoff sounds, and the film's output was connected to an impedance-matching circuit. An algorithm for determining starting and ending points of the Korotkoff sounds was established, and clinical data from subjects were acquired and analyzed to find the relationship between the values obtained by the auscultatory method and from the developed device. The results from 86 out of 90 systolic measurements and 84 out of 90 diastolic measurements indicate that the developed device pass the validation criteria of the international protocol. Correlation coefficients for the values obtained by the auscultatory method and from the developed device were 0.982 and 0.980 for systolic and diastolic blood pressure, respectively. Blood pressure measurements based on Korotkoff sound signals obtained by using the developed PVDF film-based sensor module are accurate and highly correlated with measurements obtained by the traditional auscultatory method.

• Korean Circulation Journal
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• v.54 no.5
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• pp.288-290
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• 2024

• International journal of advanced smart convergence
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• v.1 no.2
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• pp.20-25
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• 2012

The oscillometric method and Korotkoff sound method are the most common ways to measure the blood pressure. A new automatic blood pressure measurement device, which uses both oscillometric method and Korotkoff method, was developed. A pressure sensor was used to obtain cuff pressure and oscillation signal, and a microphone was used to detect Korotkoff sounds. Forty-five measurements from fifteen subjects were used for analysis. Correlation coefficients between the traditional auscultatory method and Korotkoff sound method were 0.9820 and 0.9721 for the systolic and diastolic blood pressure values, respectively. Standard deviations of differences for the systolic and diastolic blood pressure values were 1.3019 and 1.4495, respectively. Correspondingly, correlation coefficients between the traditional auscultatory method and oscillometric method using newly developed algorithm were 0.9651 and 0.9136 for the systolic and diastolic blood pressure values, with the standard deviations of 1.42 and 1.73, respectively. The results showed that the newly developed algorithm for oscillometirc method provide accurate blood pressure values, moreover, Korotkoff sound method using microphone provides even higher accuracy. Therefore, a new automatic device which utilizes both oscillometric method and Korotkoff sound method would provide the accurate and reliable blood pressure values.

• Korean Circulation Journal
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• v.54 no.5
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• pp.270-287
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• 2024

Background and Objectives: Blood pressure (BP) measurement using an auscultatory sphygmomanometer is recommended for diagnosing hypertension in children. As mercury sphygmomanometers (MSs) are banned owing to environmental concerns, it is crucial to determine the accuracy of mercury-free sphygmomanometers to replace them. We analyzed the accuracy of these devices to guide the National Survey selection. Methods: BP was measured thrice each with MS, auscultatory device (AD), and oscillometric device (OD) in 104 participants aged 10-18 using the National Survey data. The difference in BP was defined as the difference between MS and other devices. The BP differences, correlations, and influencing factors were analyzed. The frequencies of hypertension were also compared. Results: Systolic BP (SBP) and diastolic BP (DBP) differences between MS and AD were 0.88±3.36 mmHg and 0.63±3.95 mmHg, and those between MS and OD were 0.43±5.83 mmHg and 4.57±6.89 mmHg, respectively. The absolute error of <10 mmHg for DBP between MS and OD was 76%. The concordance correlation coefficient between MS and AD was 0.94 for SBP and 0.90 for DBP, and 0.81 and 0.67, respectively for MS and OD. Arm circumference negatively correlated with BP differences except for SBP between the MS and OD. The frequency of hypertension was not different between MS and AD but was underestimated by OD. Conclusions: AD correlated well with MS, while OD did not, especially for DBP. The superiority of AD over OD suggests AD as a possible alternative for MS in the National Survey.

• Journal of Chest Surgery
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• v.15 no.1
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• pp.21-26
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• 1982

Fourteen cases of funnel deformity, 11 were male and the others female, treated over a eleven-year period, are presented. The overall results with the methods described by the authors, Wada, Shannon, Adkins and Ravitch appear to be excellent. The symmetric depression was more common In children under the age of 12 years and asymmetric one Increased after the age of 12. Six cases of abnormal cardiac auscultatory findings revealed no consistent hemodynamic abnormalities. An 21-year-old female was associated with left lung agenesis and dextroversion of the heart, and a 6-year-old boy with congenital bronchogenic cyst who underwent right upper lobectomy. EKG changes associated with the anomaly were observed in all. Pulmonary function test showed the range from normal to moderate restriction which did not Improve in only one patient after operation, but the patient did not complain any restriction In activity. Some transient complications were developed which resulted in improvement.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.60 no.8
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• pp.1606-1616
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• 2011

The blood pressure measuring equipment, which is being supplied and used most widely by being recognized convenience and accuracy now generally, is oscillometric blood pressure monitor. However, a change in blood pressure is basically influenced by diverse elements such as each individual's physiological status and physical condition. Thus, the measurement of blood pressure, which used single element called oscillation in blood pressure of being conveyed to cuff, is not considered on physiological elements such as cardiovascular system status and blood vessel stiffness index, and on external elements, thereby being quite in error. Accordingly, this study detected diverse bio-signals and body informations in each individual as the measurement subject such as ECG, PPG, and Korotkoff Sound in order to enhance convenience and accuracy of measuring blood pressure in the complex measurement equipment, thereby having extracted regression method for compensation in error of oscillometric blood pressure measurement on the wrist, and having improved accuracy of measuring blood pressure. To verify a method of improving accuracy, the blood pressure value in each of SBP, DBP, MAP was acquired through 4-stage experimental procedure targeting totally 51 subjects. Prior to experiment, the subjects were divided into two groups such as the experimental group for extracting regression method and the control group for verifying regression method. Its error was analyzed by comparing the reference blood pressure value, which was obtained through the auscultatory method, and the oscillometric blood pressure value on the wrist. To reduce the detected error, the blood pressure compensation regression method was calculated through multiple linear regression analysis on elements of blood pressure, individual body information, PTT, HR, K-Sound PSD change. Verification was carried out on improving significance and accuracy by applying the regression method to the data of control group. In the experimental results, as a result of confirming error on the reference blood pressure value in SBP, DBP, and MAP, which were acquired through applying regression method, the results of $-0.47{\pm}7.45$ mmHg, $-0.23{\pm}7.13$ mmHg, $0.06{\pm}6.39$ mmHg could be obtained. This is not only the numerical value of satisfying the sphygmomanometer reference of AAMI, but also shows the lower result than the numerical value in SBP : $-2.5{\pm}12.2$ mmHg, DBP : $-7.5{\pm}8.4$ mmHg, which is the mean error in the experimental results of Brram's research for verifying accuracy of Omron RX-M, which shows relatively high accuracy among wrist sphygmomanometers. Thus, the blood pressure compensation could be confirmed to be made within significant level.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.5 no.1
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• pp.95-106
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• 1998

The purpose of this study was to compare direct and three indirect blood pressure measurements in adults and to compare among three indirect blood pressure measurements in adults. One direct(intraarterial) and three indirect(using a mecury sphygmomanometer, a aneroid type sphygmomanometer and an automatic auscultatory device) methods of blood pressure measurement were compared in adult patients who had an arterial line. The subjects for this study consisted of 29 patients in K medical center, B medical center, B hospital and M hospital in Pusan. The data was collected from October 1, 1992 to June 30, 1993. The collected data was analysed with the SPSS program, frequency, percentage, mean, S.D., t-test, ANOVA. The results of this study were as follows : 1) There was a significant difference in the systolic BP when using the direct and three indirect measurements(P<0.05). 2) There was no overall significant difference in the diastolic BP when using the direct and three indirect measurements. 3) There was no significant difference in the SBP and DBP among the three indirect measurements.

• Journal of Biomedical Engineering Research
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• v.38 no.3
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• pp.111-115
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• 2017

Blood pressure is one of the important vital signs for monitoring the medical condition of a patient. Automated NIBP(non-invasive blood pressure) monitoring devices calculate systolic and diastolic blood pressures from the oscillation in cuff pressure caused by a pulsation of an artery. To validate the NIBP devices, we developed a simulator to supply the oscillometric waveforms obtained from human subjects. The simulator provided pressure pulses to device-under-test and device readings were compared to the auscultatory references. Fully automated simulation system including OCR(optical character recognition) were developed and used for NIBP monitoring devices. The validation results using the simulator agreed well with previous clinical validation. More validation studies using the standardized oscillometric waveforms would be required for the replacement of clinical trials to validate a new automated NIBP monitoring device.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2007.06a
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• pp.678-681
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• 2007

In this study, an implementation of a system for measuring more accurate blood pressure by non-invasive methods of oscillometric was performed. The system were composed of pressure control, signal measurement, blood pressure signal processing units and wireless sensor network parts. For verify the validity of the system, tests of characteristics evaluations for pressure measurement unit, extraction of characteristic ratios for blood pressure estimation, blood pressure tracking by oscillometric method were performed. A group of five adult male was selected for the clinical test of the implemented system. The results of the oscillometric method in comparison with auscultatory method are that the maximum ratios of PAD of average, systolic and diastolic arterial pressure are 1.38%, 1.63% and 2.97% with SEP of 5.00, 3.72 and 4.34.