• 대한한의진단학회지
• /
• 제12권1호
• /
• pp.1-12
• /
• 2008

Object: The purpose of this study is to the review recent 20 years chinese achievements on the use of impedance cardiography for chinese medicine. Methods: From the China Journal Full Text Database we searched papers on the use of impedance cardiography for chinese medicine by the keyword "심조항도(心阻抗圖)". Results: The researches are summarized into 3 parts. (1) the researches on the relationship between the parameters of impedance cardiography and the chinese medical diagnoses; pulse diagnosis and tongue inspection. (2) the researches on the objective assessment using impedance cardiography for the effects of chinese medical therapy. (3) the researches on the objective evaluation index of Heart Deficiency Syndrome using impedance cardiography. Conclusion: The parameters of impedance cardiography has been established for its usefulness in various chinese medical researches.

• 대한한의진단학회지
• /
• 제10권2호
• /
• pp.67-78
• /
• 2006

Objectives : To review the method, validity and reliability of Impedance Cardiography and to study its oriental medical application. Method : The papers reviewed in this study were searched through internet search engines such as Springer, Science Direct, and China National Knowledge Infrastructure. Conclusion : In this study, the methodological limitations, validity and reliability of impedance cardiography were examined. Impedance Cardiography is recognized as a highly accurate non-invasive tool to assess hemodynamic parameters. The ability of impedance cardiography to assess hemodynamic parameters in non-invasive way is very suitable for researches on the effect of oriental medical therapeutics or the validation of oriental medical diagnostic.

• 대한한의진단학회지
• /
• 제11권2호
• /
• pp.128-140
• /
• 2007

Purpose: We performed this study to examine the correlationship between EEG complexity and impedance cardiography data using correlation analysis. Method: This study performed on 30 healthy subjects(16 males, 14 females). Before and after natural respiration, ICG data were recorded, and EEG raw data were measured by moving windows during 15 minutes. The correlation dimension(D2) was calculated from 15 minutes data. 8 channels EEG data were analysed with 9 index of ICG data by correlation analysis. Result: 1. ACI of impedance cardiography had significant correlationship with ch.4 of EEG complexity(p=0.03). 2. VI of impedance cardiography had significant correlationship with ch.3 of EEG complexity(p=0.034) and ch.4 of EEG complexity(p=0.017). 3. HR, TFC, PEP, LVET, STR of impedance cardiography had no significant correlationship with all of 8 channel EEG complexity. Conclusions: These results suggest that nonlinear analysis of EEG and impedance cardiography have some significant correlationship. And it can make out relationship between brain system and cardiovascular system. In the future, therefore, more study of these fields are necessary.

• 대한의용생체공학회:의공학회지
• /
• 제9권2호
• /
• pp.165-170
• /
• 1988

The purpose of this study was to prove the accuracy of impedance cardiography by measuring cardiac outputs of patients simultaneously by thermodilution method, and impedance cardiography developed in our department. The subjects were eight patients with mitral stenosis admitted to the cathete rization laboratory in Severance Hospital. The correlation coefficient was 0.895, which is thought quite high considering the fact that accuracy of cardiac outputs of patients with valvular diseases measured by both methods was known to be low.

• 대한한의진단학회지
• /
• 제11권1호
• /
• pp.82-104
• /
• 2007

Purpose: We performed this study to examine the effect of controlled respiration on cardiovascular system in healthy adult subjects using impedance cardiography and photoplethysmography. Materials and Methods: This study had performed on 74 subjects, which were healthy men and women without a experience of respiration practice. Using the instruments for impedance cardiography and photoplethysmography, parameters of each subject had been measured after each controlled respirations which were natural respiration, controlled natural respiration (I:E=1.1.6), longer inspiration(I:E=3:3), and longer expiration(I:E=2:4). The measured parameters of impedance cardiography and photoplethysmography were processed statistically by one-way repeated ANOVA. Results: 1. HR and CI of impedance cardiography were decreased significantly during controlled respiration comparing with the result of basal state(the state of enough break). There was no significant difference among the results of controlled respiration. 2. PEP of impedance cardiography had no significant difference among the result of basal state and the results of controlled respiration(p=0.059). 3. VI of impedance cardiography had significant differences among the result of basal state and the results of controlled respiration, and decreased continuously through the controlled respiration. 4. b/a of photoplethysmography had no significant difference among the result of basal state and the results of controlled respiration(p=0.554). 5. c/a of photoplethysmography were decreased significantly during controlled respiration comparing with the result of basal state. There was no significant difference among the results of controlled respiration. 6. d/a of photoplethysmography had significant differences among the results of the controlled respiration decreasing continuously through the controlled respiration and had no significant difference between the result of basal state and the result of natural respiration. 7. AGI of photoplethysmography had significant differences among the result of basal state and the results of the controlled respiration increasing continuously through the controlled respiration. Conclusion: We had examined the effects of controlled respirations on cardiovascular system in multiple points of view. The effects of controlled respirations on cardiovascular system can't be explained in a simple way, as the cardiovascular system is controlled by many factors. Therefore, more physiological parameters must be measured in the future study on the effect of the controlled respiration on human cardiovascular system.

• 대한의용생체공학회:의공학회지
• /
• 제10권3호
• /
• pp.279-284
• /
• 1989

Measurement of cardiac output during exercise by noninvasive technique is very needed in the area of sports medicine. However there are only two noninvasive techniques, one of which is $CO_2$ subscript rebreathing technique and the other one is impedance cardiography. While $CO_2$ rebreathing technique needs special breathing and metablic steady state, impedance cardiography has motion Uiiau problem. In this study maior sources of the mothion artifact during treadmill exercise was found experimentally to. be the impact caused by each step on the treadmill. Thus special shoes to reduce the impact were developed. These are the shoes with silicon rubber and hard sponge attached to the soles. It was possible to measure cardiac output with the newly developed shoes for Burke protocol whose speed of the treadmill was constant 3.5 miles/hour while it was impossibel with the conventional exercise shoes.

• 대한인간공학회지
• /
• 제11권1호
• /
• pp.67-79
• /
• 1992

Cardiac systolic time intervals (STLs) and Heather index (HI) were used to access changes in left ventricular function of six male subjects exposed to postural changes,$0^{\circ}C$, ${\pm}2^{\circ}C$, ${\pm}45^{\circ}C$, ${\pm}90^{\circ}C$, Significant prolongation of the pre-ejection period (PEP) and PEP/ LVET ratio, shortening of the left ventricular ejection time (LVET), STI, HI and $1/PEP^{2}$were observed during exposure to both $+45^{\circ}C $ and $+90^{\circ}C $But the values measured during $-45^{\circ}C $ and$-90^{\circ}C $ were reversed. Changes in fluid shift, filling volume, preload, after load and sympathetic activities may account for the observed findings. Early response of cardiac foctions was recorded using impedance cardiography. This method is very simple but accurate. Thus it will be useful in this aerospace and work physiology. In conclusion, STIs appear to provide reliable noninvasive method for examining changes of cardiac function during exposure to postural changes.

• 대한의용생체공학회:의공학회지
• /
• 제9권1호
• /
• pp.109-116
• /
• 1988

In this paper, principles of impedance tenchinque and relationship between stroke volume and impedance change were theoretically explained. An impedance cardiograph was designed and constructed. Its reproducibility was verified by experiment. Until now, the peak point of dZ/dt waveform, first derivative of impedance change(${\Delta}$Z) , has been detected by software technique requiring considerable time to process. However in this paper its peak point was found using hardware for saving processing time. Useful cardiac parameters such as stroke volume and contractility of cardiac muscle were measured noninvasively. The reproducibility of the instrument was measured to be better(less than 10%) than that of clinical standard method such as thermodilution (more than 30%). Hence impedance cardiography was found to be better techique for monitoring stroke volume and myocardial contractility for pre and post operation, and pharmacological studies.

• 전기학회논문지
• /
• 제64권8호
• /
• pp.1251-1255
• /
• 2015

The purpose of this study is to measurement the cardiac output using hand to hand impedance method to provide convenience to user when measuring SV(stroke volume) with the use of ICG(Impedance Cardiography). We suggest the optimized modified formula, which can be applied when using impedance with the use of hand to hand Impedance. To verify this formula, a SV from transthoracic approach and hand to hand approach are compared for the 36 subjects, respectively. The acquired data was analyzed by using LabVIEW 8.6, analysis was implemented by SPSS 12.0. Fine difference was shown by individual. We showed that as a result of analyzing the ICG measurement value on thoracic and hand to hand, the correlation with SV was r=0.716, thereby having indicated the results of regression model in relatively high correlation.

• 대한의용생체공학회:학술대회논문집
• /
• 대한의용생체공학회 1989년도 춘계학술대회
• /
• pp.71-73
• /
• 1989

The origins of the motion artifact resulting from exercise in impedance cardiography wore explained and the ensemble average technique was applied to reduce the motion artifact enabling the measurement of cardiac output during exercise. Algorithm for ensemble average was developed and applied to the actual impedance signals. It was found that the minimum number of sampling was 20, and sampling frequency was 500Hz. Using the ensemble average technique it was possible to measure cardiac output continuously during the treadmill exercise. Therefore it is hoped that this study may contribute in the area of exercise physiology and sport medicine.