Agreement analysis of stroke volume and cardiac output measurement between a oscillometric device and transthoracic echocardiogram in normotensive individuals: a preliminary report

Abstract Introduction The evaluation of stroke volume (SV) is useful in research and patient care. To accomplish this, an ideal device should be noninvasive, continuous, reliable, and reproducible. The Mobil-O-Graph (MOG) is a noninvasive oscillometric matrix validated for measuring aortic and peripheral blood pressure, which through conversion algorithms can estimate hemodynamic parameters. Objectives To compare the MOG measurement of stroke volume, cardiac output, and cardiac index with the transthoracic echocardiogram (TTE). Methods Healthy volunteers aged 18 years or older were included. Two-dimensional TTEs were performed by a single operator. Subsequently, the measurement of noninvasive hemodynamics with MOG was performed with the operator blind to the results of the echocardiogram. Correlation analyses between stroke volume, cardiac output, and cardiac index parameters were performed. The degree of agreement between the methods was verified using the Bland-Altman method. Results A total of 38 volunteers were enrolled with a mean age of 27.6 ± 3.8 years; 21 (55%) were male The SV by TTE was 76.8 ± 19.5 mL and 75.7 ± 19.3 mL by MOG, Rho = 0.726, p< 0.0001. The CO by TTE was 5.04 ± 0.8 mL.min-1 and 5.1 ± 0.8 mL.min-1 by MOG Rho = 0.510, p= 0.001. Bland-Altman plots showed a good concordance between the two techniques. Conclusions Our study shows that the measurement of SV and CO by noninvasive hemodynamics with the MOG device offers a good concordance with the TTE with very few values beyond the confidence limits.

Discussion on performance testing techniques of non-invasive automated sphygmomanometer (oscillometry) / 医疗卫生装备

Objective To promote the development of non-invasive automated sphygmomanometer (oscillometry) performance testing technology by studying the related technologies and devices.Methods The performance testing contents of noninvasive automated sphygmomanometer (oscillometry) were summarized based on data inquiry and etc,involving in static and dynamic performance testing.The technical characteristics of the blood pressure simulator for testing non-invasive automated sphygmomanometer were analyzed,and the current market situation of the blood pressure simulator was described.Results The blood pressure simulator showed problems in concept,traceability and calibration.Conclusion To develop a new generation of blood pressure simulator is the development direction of non-invasive automated sphygmomanometer (oscillometry) performance testing technology.

The research and practice of double-cuff method used to calculate pulse wave velocity / 重庆医科大学学报

Objective:A new method of measuring pulse wave velocity,double-cuff method,has been proposed based on oscillometric method and used to practice to validate its reliability in this paper.Methods:In this method,two cuffs are used to collect pulse wave signals of humerus and oar artery respectively.We analyse the two signals'time difference ?t by choosing wave boot as the pulse beating' start point.Pulse wave velocity can be calculated according to the formula PWV=?S/?t,in which ?S is the distance between humerus and oar artery and can be measured by a soft ruler.Results:The double cuff method,which has the advantages of simple operation,speedy measurement and low cost,can measure pulse wave velocity reliably,accurately,fast and simply.Conclusions:The pulse wave velocity measured by this new method,which can reflect the differences between normal people and critical or already hypertension suffers,is significant in forecasting hypertension.

A New Algorithm for Oscillometric Blood Pressure Measurement / 航天医学与医学工程

Objective To find a new algorithm for oscillometric blood pressure measurement. Method A coefficient difference comparative method was proposed to measure the difference of adjoining pulse waves and their comparative ratios. And the turning point was judged by priority way in the range. Result The new method settled the problem of miscarriage of justice of the turning point around average pressure and improved the accuracy of blood pressure measurement. Conclusion It can detect difference between cardiovascular patients and normal persons. And it is effective and reliable in blood pressure measurement. It provides a convenient method for researching, preventing and epidemiological studies of cardiovascular diseases in our country.

Principle and Testing of Electronic Blood-Pressure Meters(Oscillometric Method) / 医疗卫生装备

The working principle of oscillometric method are introduced in Indirect Blood Pressure(INBP) measurement,and the various algorithms in this field are compared.In addition,the framework of INBP simulator used to test or calibrate electronic blood-pressure meters is described.The restriction of the simulator to calibrate INBP is also discussed.

Research and design of electronic sphygmomanometer based on charge measurement / 医疗卫生装备

In allusion to the defects of traditional electronic sphygmomanometer in deflation process,this paper puts forward an innovative way which accomplishes the measure of blood pressure during charge process based on oscillometric method.It is proved to be more energy-saving,more subminiature,less measuring time and more stable for individual.

Study on difference of noninvasive blood pressure measurement method based on oscillometric and auscultatory / 医疗卫生装备

This paper introduces and compares several blood pressure measurements, among which two noninvasive blood pressure measurements based on oscillometric and auscultatory methods are mainly compared. It also analyses the characteristics and advantages of oscillometric method as well as introduces a noninvasive blood pressure measurement monitor based on oscillometric. By using this monitor and a common auscultory method, we conducted a public survey. The result for statistical data analysis showed that the difference between oscillometric and auscultatory methods are quite small, and the accuracy of them are both quite good .This paper also previews the future of the noninvasive blood pressure measurement

Oscillometric Blood Pressure of Upper and Lower Extremities and Aortic Blood Flow Velocity in Neonates

PURPOSE: We studied the blood pressure difference between the upper and lower extremities in healthy newborn infants and the effect of isthmic narrowing of the aorta on making a possible difference. METHODS: The blood pressure was measured with an oscillometric blood pressure device from four extremities of 62 healthy infants aged 1-15 days. A Doppler echocardiography was performed for each infant to measure the aortic blood flow velocities in the ascending, just above and below the aortic arch isthmic narrowing. RESULTS: The blood pressure readings were as follow : right arm 69.7 (+/-7.5)/42.7(+/-7.2)mmHg, right calf 69.5(+/-6.1)/42.6(+/-6.3)mmHg, left arm 69.0(+/-7.3)/43.1(+/-6.3)mmHg, and left calf 68.9(+/-7.4)/42.9(+/-5.6)mmHg. The estimated pressure gradient between the ascending aorta and aorta below the isthmus was 2.4+/-1.3mmHg and between opposite sides of the isthmus was 1.2+/-0.8 mmHg. CONCLUSION: Unlike in childhood and adolescence, the blood pressure in the lower extremities of healthy newborn infants is not higher than in the upper extremities. But the isthmic narrowing of the aortic arch does not explain this phenomenon.

Oscillometric Blood Pressure Values of Infants and Children

PURPOSE: Automated oscillometric blood pressure measurement is not used universally, but has a tendency to be used more frequently in pediatric areas. Reference values of blood pressure by this method were not reported on infants and children under 5 years of age in Korea. This study was performed to study normative blood pressure values by using oscillometric method, presenting 95 percentites on Korean infants and children by age, sex, and weight. METHODS: The subjects were 2,989 normal infants and children from birth to 11 years of age. Blood pressure was measured three times by automated oscillometric method. Percentile values of systolic and diastolic blood pressure were presented according to age, sex and weight. RESULTS: There were no differences in systolic and diastolic blood pressure between male and female in these age groups. Systolic and diastolic blood pressure values increased significantly with increasing age and also with increasing weight. Blood pressure was more correlated with weight than with age. CONCLUSION: Oscillometric blood pressure values in infants and children were presented by age, sex and weight. These normal blood pressure values may be useful in identifying hypertension in Korean children.