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In this study a telemedicine system based on embedded computer system is presented, which is designed specially for the need of immediate medical treatment in remote areas. In the system embedded Linux is cut down, customized and ported into the monitor terminal. Data interchange between the monitor center and the terminal via Internet and GPRS is introduced. This system which is convenient, portable...
We built a pulmonary and cardiovascular integrated model which is driven by O2 consumption. The integrated model consists of a pulmonary model, a cardiovascular model, a gas exchange model, a respiratory control system model and a cardiovascular control model. To verify the integrated model, we calculated ventilations and cardiac outputs in different O2 consumptions and compared the results with literature...
Impulse oscillometry (IOS) is an innovative patient-friendly pulmonary testing technique which measures the respiratory system impedance (Z) by using the spectral components of pressure to flow ratio which yields resistance and reactance values at different frequencies. The high dimensionality of IOS measurement data makes the analysis of this information difficult. Artificial neural networks (ANNs)...
The paper describes three types of artificial gas exchange techniques for respiratory failure; extracorporeal membrane oxygenation (ECMO) for acute respiratory failure address the problem of oxygenation and CO2 removal; arteriovenous carbon dioxide removal (AVCO 2) for acute and respiratory failure with residual function, achieve total CO2 removal supplement native lung apneic oxygenation; paracorporeal...
Following up on our previous work, we have developed one more non-contact method to measure human breathing rate. We have retrofitted our mid-wave infra-red (MWIR) imaging system with a narrow band-pass filter in the CO2 absorption band (4.3 mum). This improves the contrast between the foreground (i.e., expired air) and background (e.g., wall). Based on the radiation information within the breath...
Previous studies in various animal models have shown that respiratory premotor and motor neurons undergo rapid changes in biochemical and bioelectric properties during the first month of postnatal life. Early in postnatal life, there is an increase in the complexity of the morphology of the dendritic tree of respiratory neurons as it changes from a bipolar to a multipolar morphology. During normal...
The present study provides further insights into the chaotic nature of the ventilatory behaviour in spontaneously breathing healthy humans by applying the noise titration method to ventilatory flow signals gathered in this setting. In five subjects with normal breathing pattern and end-tidal CO2, the noise titration method gave a positive noise limit ranged from 6 to 43%. Our study shows that the...
Sleep studies are considered a paradigmatic example of the complex cardiorespiratory interactions, with an important impact also for clinical implications: diagnosis and treatment control, not only for the classical common sleep disturbances, but also for obstructive sleep apnea (OSA) or central apnea (CA) which are often associated with an increased risk of cardiovascular pathologies, such as hypertension,...
To investigate the effects of voluntary breathing on respiratory sinus arrhythmia and nonlinearity of heart rate variability (HRV), two kinds of voluntary breathing, speech and breath-holding, were used. The results showed that both types of voluntary breathing diminished the high frequency component of HRV, but speech decreased, while breath-holding enhanced the nonlinearity of HRV as detected by...
Studies suggest that obstructive sleep apnea syndrome (OSAS) is causally related to abnormal cardiovascular autonomic control in adults, but this has not been established in pediatric OSAS. The goal of this study was to quantify autonomic system dysfunction, as manifested by cardiovascular response abnormalities, in children with OSAS. During wakefulness, we continuously measured the ECG, arterial...
Current alarm strategies for physiological monitoring depend on predetermined thresholds without consideration for the heterogeneity between patients or intraoperative variations. To improve upon this situation, we developed an adaptive change point detection scheme to automatically notify the clinician when a change of clinical significance has occurred in the respiratory variables. We modeled end-tidal...
We searched for possible associations between various measures of severity of sleep-disordered breathing (SDB) and indices of cardiac autonomic function in older subjects (>60 years). Twenty four overnight unattended home-based polysomnograms obtained from the Sleep Heart Health Study were analyzed using spectral analysis. For each subject, six autonomic indices reflecting heart rate variability...
For any respiratory sound analysis or assessment, respiratory flow must also be measured simultaneously with the sounds. However, due to difficulties and/or inaccuracy of the most flow measurement techniques, several researchers have attempted to estimate flow from respiratory sounds. However, all of the proposed methods heavily depend on the availability of different rates of flow for calibration...
On the body surface the electric field generated by the cardiac muscles consists of electric potential maxima and minima that increase and decrease during each cardiac cycle. The recording of these electric potentials as a function of time is called electrocardiography, and the resulting signal is called the electrocardiogram (ECG). The ECG signal is used extensively as a low cost diagnostic tool...
Spectral analysis was carried out on the R-wave attenuation (RWA) trend and heart rate variability (HRV) series, derived from the polysomnographic electrocardiogram (ECG) of the subjects with and without Cheyne Stokes breathing. Nocturnal polysomnography was performed on 16 normal subjects and 7 subjects with Cheyne Stokes breathing (CSB) patients. The polysomnographic ECG data was divided into fifteen...
Brain hemodynamic responses (BHR) of healthy subjects and migraineurs performing a breath holding task are measured by functional near-infrared spectroscopy (fNIRS) method. The response curves are deconvolved from a rectangular input function to yield the impulse response (IR) function of BHR which was then modeled by a summation of three gaussians. Our results show that the amplitude coefficients...
An analysis of pulse-to-pulse interval (PPI) derived from non-contact photoplethysmography (PPG) is performed using the Poincare plot technique. Eleven healthy volunteers participated in a protocol utilising both spontaneous and paced breathing methodologies with a customised non-contact PPG system to obtain adequate quality signals for a distance of 80 mm between source and detector. An adaptive...
In this paper, we propose a measuring device implementation to measure ECG, 50 KHz BIA for getting BIA/respiration, and 10~50 Hz GSR for measuring electrical characteristics of skin. To this end, BIA signal is separated by line filter and high impedance element and the interference between signals could be minimized by switching in time domain to separate ECG and GSR signals having the similar frequency...
Current models of lung mechanics and gas exchange act independently to simulate variations in pressure-volume (PV) and ventilation-perfusion (V/Q) properties in the lungs respectively. However, changes in ventilator pressures can cause alveoli recruitment, collapse or over-distension causing V/Q changes in the lungs that are unaccounted for in these models. A compartmental model of the lungs is presented...
Very slow yogic breathing techniques provide valuable insights into mechanisms of autonomous nervous system regulation that are usually not available for human subjects. This paper presents results of eight sessions of Nadi Shodhana Pranayama practiced at rate of one breath per minute. We characterized statistic and spectral measures of heart rate variability before, during, and after exercises. Significant...
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