ABSTRACT
<p><b>OBJECTIVE</b>To propose a new method for acquiring pulmonary function parameters based on measurement of volume changes of thoracic impedance.</p><p><b>METHODS</b>We studied the relationship between the volume changes of thoracic impedance and pulmonary function parameters during forced breathing based on bioimpedance measurement, and developed an instrument for measuring thoracic impedance. Using this instrument and a MRI spirolab III lung function test instrument, both based on flowmeter measurement, we measured such pulmonary function parameters including forced vital capacity (FVC), forced expiratory volume in one second/FVC (FEV1/FVC), and peak expiratory flow in 10 healthy volunteers and compared the measurement results.</p><p><b>RESULTS</b>The differences in the parameters measured using the two instruments were all within two folds of the positive and negative standard deviations of the average values, demonstrating good consistency in the measurement between the two methods.</p><p><b>CONCLUSIONS</b>The measurement results of the bioimpedance-based instrument we developed show good consistency with those by the commercially available pulmonary function test instrument.</p>
Subject(s)
Adult , Humans , Young Adult , Electric Impedance , Forced Expiratory Volume , Peak Expiratory Flow Rate , Respiratory Function Tests , Methods , Thorax , Physiology , Vital CapacityABSTRACT
A novel blood pressure measurement system was designed which based on auscultatory method. And the electret sensor that embedded into the internal instrument can detect the Korotkoff-sound signal directly which is coupled by the cuff and transmitted in the cross connection. The BP values identification algorithm is based on combined detection of Korotkoff-sound and pulse signal, and the products of amplitudes and energies are calculated as the characteristic values of Korotkoff-sound, and the Korotkoff-sound phases are classified and detected by means of clustering of characteristic values, and then BP parameters are determined. The contrast test and statistical analysis showed good consistency and accuracy between the new BP detection method and conventional mercury sphygmomanometer.
Subject(s)
Blood Pressure , Blood Pressure Determination , Methods , Equipment DesignABSTRACT
This paper is aimed to study the feasibility of myocardial infarction risk assessment by noninvasive multivariable trend analysis, including heart rate variability (HRV), deceleration capacity (DC) of heart rate and pulse wave velocity (PWV). Thirty five patients with cardiovascular diseases (11 Myocardial infarction (MI), 8 coronary artery disease (CAD), 6 artery atherosclerosis (AA) and 10 hypertension), and 31 healthy subjects were randomly selected into a control group for this research as comparison. 15 min ECG and 1 min pulse wave data were collected based on the analysis workbench developed by our Lab. HRV, DC and PWV between the cardiovascular group and the control group were analyzed and compared. The results showed that the HRV indices, DC and PWV were significantly higher than those in the control group. The DC and the HRV indices including NN50, PNN50 and TINN especially presented a decline trend that was consistent with the regularity of cardiovascular development process. This noninvasive multivariable trend analysis of HRV, DC and PWV can be a reference for the earlier risk prediction of MI.
Subject(s)
Aged , Female , Humans , Male , Middle Aged , Electrocardiography , Forecasting , Heart Rate , Multivariate Analysis , Myocardial Infarction , Pulse , Risk AssessmentABSTRACT
<p><b>OBJECTIVE</b>To assess mental fatigue by noninvasive monitoring of the physiological signals.</p><p><b>METHODS</b>The changes in the physiological parameters including the electrodermal activity, heart rate and heart rate variability were analyzed in 14 subjects performing the reaction-time tasks when fatigue and changes in the reaction time occurred.</p><p><b>RESULTS</b>The average skin conductance level, average heart rate, and heart rate variability parameters including the total power density, percentage of the very low power density, percentage of high power density all differed significantly between the sober state and the mental fatigue state.</p><p><b>CONCLUSION</b>Monitoring the physiological parameters including the electrodermal activity, heart rate and heart rate variability is a noninvasive, effective and practical approach to mental fatigue assessment.</p>
Subject(s)
Adult , Humans , Male , Young Adult , Galvanic Skin Response , Physiology , Heart Rate , Physiology , Mental Fatigue , Reaction TimeABSTRACT
This article describes a design of physiological signal storage format and transfer protocol for the tele-medical system between home and community. The protocol is based on ASCII character, with frames as its basic structure. There are two kinds of frames: control frames and data frames. Control frames can start and stop data transfer, confirm the order, and ask for start. There are seven kinds of data frames, according to the different data types. Data is transferred in data frames. The protocol described in this article is simple and extensible. The design target has been accomplished in real system.
Subject(s)
Community Health Services , Methods , Medical Informatics Applications , Software Design , Telemedicine , MethodsABSTRACT
Lives are maintained by enough oxygen.Blood oxygen saturation is one of the important parameters which reflects oxygen concentration in blood.The accurate monitoring of blood oxygen saturation is very important to both physiological research and medical application.At present,dual-wavelength method is widely adopted in noninvasive detection of blood oxygen saturation.Therefore,accurate recognition of peak-to-peak value of pulse waveform is a key process in monitoring blood oxygen saturation.In the paper,LMS self-adaptive arithmetic is applied to processing pulse waveform signal.The ratio of corrective detection is improved by the method.
ABSTRACT
Objective To study the association between sympathetic skin response(SSR) and diabetic autonomic neuropathy(DAN), and explore its use as the objective base for its early diagnosis. Methods SSR was carried out in 30 patients with DAN and 30 healthy controls. Results The SSR indices of the patient with diabetic mellitus(DM) either with or without DAN were different from those of normal objects. Conclusion The SSR detection and analysis can detect the early dysfunction of the autonomic system in diabetic mellitus and may be a useful testing for early diagnosis of diabetic neuropathy.
ABSTRACT
Objective To study non-invasive measurement of reflectance oxygen saturation.Methods Diffusion theory was used to explain the action of light in tissue and deduce reflectance oxygen saturation formula.Then,Reflectance Oxygen Saturation Detection System based on MSP430 was developed and calibrated.Result The calibration result and calibration curve was ascertained and analyzed.Conclusion The formula for detection and measurement of oxygen saturation is put forward by using Reflectance Oxygen Saturation Detection System.