Lung function monitoring is a critical technique for clinical medicine. Currently, the lung function testing devices used in our domestic hospitals are both expensive and bulky. A portable and accurate lung function parameters testing system is highly desired and is proposed in this paper. The hardware of the system is based on DSP technology. The breathing passage is designed with an aim suitable for the breathe and signal detection. We use the direct detection method to detect the gas flow, the breathing passage pressure and the breathing time. Thanks to the powerful data processing ability and the high operation speed of the DSP, breathing signals can be easily analyzed. Thus, several lung function parameters of clinical significance can be obtained. Experiments show that the accuracy of the system is better than 3%, and could meet the demand of the lung function testing.
Humans ; Respiratory Function Tests ; instrumentation ; methods ; Software ; Software Design

Respiratory mechanical parameters are the key indexes in evaluating the respiratory function of an anaesthetized patient during operation. The measurement of respiratory parameters plays an important role in clinic, and can dynamically monitor the working state of a respirator, direct the use of a respirator and monitor the respiratory function of a patient in intensive care unit(ICU). This paper introduces a new method that will break the traditional limitations, can measure eleven respiratory parameters and demonstrate the results by digital and diagrams.
Equipment Design ; Models, Biological ; Respiratory Function Tests ; instrumentation ; methods ; Software

This paper introduces the design and implementation of a novel respiratory detecting system based on bio-impedance method. By increasing electrodes in space, the system make multi-channel respiratory signals be superpositioned and filtered (SNR); Traditional filter methods by both hardware and software are also used to further increase anti-interference ability. A low consumption and portable instrument is designed based on MSP430 Micro Controller Unit (MCU), The experiment shows a better performance in the reduction of interference noises of heartbeat and blood flow especially the motion artifact. Also the system works stably.
Electric Impedance ; Electrodes ; Respiratory Function Tests ; instrumentation ; methods ; Software

This article introduces a method of thoracic impedance, evaluation indexes and evaluation method for the respiration monitoring, including the methods basing on lab testing and clinical database testing, it will provide a reference for improving the efficiency of respiration monitoring.
Databases, Factual ; Humans ; Monitoring, Physiologic ; instrumentation ; methods ; Respiration ; Respiratory Function Tests ; Respiratory Physiological Phenomena

This paper introduces the latest developments of the monitoring techniques for electroencephalogram (EEG) bispectral index (BIS), pulse indicator continuous cadiac output (PiCCO), entropy index (ENTROPY), internal organs blood stream perfusion (TONO), neuromuscular transmission (NMT) and spirometry, and their clinical applications.
Electroencephalography ; methods ; Entropy ; Heart Function Tests ; methods ; Humans ; Monitoring, Physiologic ; methods ; Neurologic Examination ; methods ; Respiratory Function Tests ; methods ; Signal Processing, Computer-Assisted

OBJECTIVEImpulse oscillometry (IOS) is a new method for determination of breathing mechanics, which features convenient operation, good repeatability and wider range analysis. As there is no standardized normal value in China at present, this study will provide a normal value of lung function determination by impulse oscillometry for children in Chengdu area.

METHODTotally 549 children were chosen at random from Chengdu area, with 292 boys and 257 girls who were 4 to 14 years old. The subjects were assigned into 10 age groups according to their chronological age with one year difference between every two adjacent groups. The respiratory total impedance (Zrs), viscosity resistance (Rrs) and elastic resistance (Xrs) at various oscillation frequency were measured by the Master Screen IOS which was manufactured by German Jaeger Company. The measured data were treated with the linear stepwise multiple regression, and established the prediction equation. At the same time, paired comparison was carried out with the measured data and equation obtained from this study, Lechtenboerger equation and prediction equation obtained from Guangzhou area.

RESULTThe total impedance and airway resistance were negatively correlated with the children's height and age. Zrs (male) = -0.756 + 189.586/height, r = -0.782, P < 0.001; Zrs (female) = -0.497 + 152.468/height, r = -0.726, P < 0.001. Rrs became the same in trend; while Xrs were proportional to the height, e.g. the values increased as the height increased. The difference of the airway resistance (R(5)-R(20)) was negatively correlated with the children's height: R(5)-R(20) (male) = 0.601 - 0.0034 x height, r = -0.677, P < 0.001; R(5)-R(20) (female) = 0.549 - 0.0031 x height, r = -0.658, P < 0.001. Among the relationships with many impulse oscillometry parameters, height ranked at first place; age at second. The multiple regression equation of IOS primary index was established. Both the measured data and the correlation coefficient of the study obtained equation were greater than the coefficient correlation of the Lechtenboerger equation, but had no significant difference compared with that of prediction equation in Guangzhou area.

CONCLUSIONThe normal value in impulse oscillometry in children in Chengdu area is different from the predicted parameters in other countries. The equation obtained from this study seems to be more suitable for the children in its local area. It is recommended to apply the predicted value from the corresponding population in the determination of the lung function by impulse oscillometry.

Airway Resistance ; physiology ; Child ; China ; Electric Impedance ; Female ; Humans ; Male ; Oscillometry ; methods ; Respiratory Function Tests ; methods ; Respiratory Physiological Phenomena

BACKGROUND AND OBJECTIVES: Obstructive sleep apnea syndrome(OSAS) is characterized by repeated apnea, hypopnea, and micro-arousals during sleep. Among various treatment modalities of OSAS, continuous positive airway pressure(CPAP) treatment is the most effective and successful. The aim of this study was to compare efficacy and safety of newly developed Korean CPAP with standard CPAP in OSAS patients. MATERIALS AND METHOD: In total, 20 of 26 recruited OSAS patients completed the study. All subjects first used the standard CPAP for 4 weeks. After an at least 2 week wash-out period, the subjects used the newly developed CPAP for 4 weeks. Polysomnography, questionnaires associated with sleep, lipid profile, pulmonary function test, cardiac marker, and physical examinations were evaluated at baseline and were followed-up after each treatment. RESULTS: After treatment with the newly developed CPAP, the apnea-hypopnea index was decreased from 53.2/hr to 2.5/hr and was equivalent to that of the standard CPAP. Most of the changes in questionnaire scores, laboratory findings, and physical examinations after newly developed CPAP treatment were equivalent to those with standard CPAP. No serious adverse events were observed during the study. CONCLUSION: The efficacy and safety of a newly developed CPAP are equivalent to those of standard CPAP in OSAS patients.
Apnea ; Continuous Positive Airway Pressure* ; Humans ; Methods ; Physical Examination ; Polysomnography ; Respiratory Function Tests ; Sleep Apnea, Obstructive*

A coupling principle of reflecting impedance based on resonance is designed to achieve impedance detection with high sensitivity. It is characterized by small impelled current, high sensitivity and simple circuit. The principle can be used not only in detecting human respiratory impedance, but also in detecting the bio-impedance of other human organs. It may find wide application in this aspect.
Electric Impedance ; Equipment Design ; Humans ; Respiratory Function Tests ; instrumentation ; methods ; Software Design

This paper introduces a random measurement analysis of, lung function measurement values with two different apparatus. in 41 patients. It shows that the differences are not statistically significant (P>0.05) between two apparatus measurement values except DLCO, FEF25, FEF75 in the group of normal ventilation, FVC in the group of abnormal ventilation. The two groups are both correlated closely (r> 0.9) except MMF(r=0.7725, RV r=0.808) in the normal group of ventilation, and FEF75 (r=0.58) in the abnormal group of ventilation (p<0.001). The two apparatus with different measuring theories have a good correlation.
Adult ; Aged ; Female ; Humans ; Male ; Middle Aged ; Respiratory Function Tests ; instrumentation ; methods

Objective: To explore the influence and significance of respiratory filter on the judgment of pulmonary function and the conclusion of occupational health examination in occupational health examination. Methods: From August to November 2020, 252 occupational health examinees were randomly selected as the research objects, and the lung function was examined with the respiratory filter bite and the straight cylinder bite without filter, respectively. The lung function examination indexes and the qualification rate of lung function examination were analyzed and compared between the two groups, and the diagnostic criteria of lung function examination was corrected. Results: 252 subjects were 36 (30, 42) years old. The qualified rate of lung function examination with respiratory filter bite (28.17%, 71/252) was lower than that with straight cylinder bite (34.92%, 88/252) , the difference was statistically significant (P<0.05) . The percentage of forced vital capacity in normal predicted value (FVC%) , percentage of forced expiratory volume in the first second in normal predicted value (FEV(1)%) , and percentage of forced expiratory volume in the first second in forced vital capacity (FEV(1)/FVC%) of subjects using respiratory filter bite were lower than those using the straight cylinder bite (P<0.05) . The corrected diagnostic criteria of pulmonary function were FVC%>78%, FEV(1)%>77%, FEV(1)/FVC%>68%. There was no significant difference between the qualified rate of the respiratory filter bite lung function test calculated according to the corrected diagnostic criteria (35.71%, 90/252) and the qualified rate of the straight cylinder bite lung function test calculated according to the original diagnostic criteria (34.92%, 88/252) (P>0.05) . Conclusion: In occupational health examination, the use of respiratory filter may affect the results of pulmonary function examination. The diagnostic criteria of pulmonary function can be corrected according to different filtering effects to ensure the accuracy of the conclusions of occupational health examination.
Humans ; Adult ; Occupational Health ; Lung ; Vital Capacity ; Forced Expiratory Volume ; Respiratory Function Tests/methods*