Mechanical force plays an important role in physiological function and pathophysiologic conditions of respiratory system. Recently, a number of researches focused on how mechanical force affected pulmonary cells. This paper reviews the molecular basis of mechanical force in detail. The significance of mechanical force in respiratory therapy is also discussed.
Airway Resistance ; Biomechanical Phenomena ; Humans ; Lung Compliance ; Respiratory Mechanics ; physiology ; Respiratory Physiological Phenomena ; Respiratory System

OBJECTIVEAfter performed symptom-limited maximum cardiopulmonary exercise testing (CPET) before and after acute alkalized blood, we repeated CPET with pure oxygen.

METHODSFive volunteers, 3hr after alkalizing blood room air CPET, re-performed CPET inhaling from Douglas bag connected with pure oxygen tank. We compared with those of room air CPETs before and after alkalized blood.

RESULTSAfter alkalized blood oxygen CPET had a similar response pattern as those of CPETs before and after blood alkalization. During the CPET, all breath frequency, minute ventilation and tidal volume at each stage were similar to those of CPETs before and after alkalized blood (P > 0.05),except there was a lower peak tidal volume than those of both CPETs and a slightly higher resting minute ventilation only than CPET after alkalized blood (P > 0.05). After alkalized blood, oxygen CPET, all PaO2 and SaO2 and most Hb were lower than those of both CPETs (P < 0.05). The pHa and [HCO3-]a were higher than those of CPET before alkalized blood (P < 0.05); but were not CPET after alkalized blood (P > 0.05). PaCO2 was similar to that of CPET before alkalized blood (P > 0.05), but was lower than that of CPET after alkalized blood at resting and warm-up (P < 0.05); then was similar to both CPETs at anaerobic threshold (P > 0.05); but was higher at peak exercise higher than those of both CPETs (P < 0.01). Oxygen increased 2,3 volunteers' workload and time at AT and peak exercises.

CONCLUSIONRespiratory response pattern to oxygen CPET after alkalized blood is similar to those of both CPETs before and after alkalized blood. The CPET response is dominantly depended upon metabolic rate, but not levels of pHa, PaCO2 and PaO2.

Blood Gas Analysis ; Exercise Test ; Humans ; Oxygen ; Respiratory Physiological Phenomena

OBJECTIVEThe modern systemic physiology, based on limit-understand functional classification, has significant limitation and one-sidedness. Human being is organic; we should approach the mechanism of control and regulation of breathing integrating all the systems.

METHODSWe use new theory of holistic integrative physiology and medicine to explain the mechanism of control and regulation of breathing.

RESULTSExcept the mean level information, the up-down "W" waveform information of arterial blood gas (ABG) is core signal to control and regulate breathing. In order to do so, we must integrate all systems together. New theory will help to explain some unanswered questions in physiology and medicine, for example: fetal does not breathing; how first breath generate; how respiratory rhythm and frequency generate, etc.

CONCLUSIONBreathing is the sign of life. Mechanism of control and regulation of breathing has to integrate respiration, circulation, nerves, metabolism, exercise, sleep and digestion, absorption and elimination and etc altogether.

Holistic Health ; Humans ; Integrative Medicine ; Respiration ; Respiratory Physiological Phenomena

Humans ; Muscular Dystrophy, Duchenne ; physiopathology ; therapy ; Respiratory Physiological Phenomena

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

OBJECTIVEExercise induced oscillatory ventilation (EIOB) during cardiopulmonary exercise testing (CPET) is associated with severity and prognosis of disease, but clinical approach for the character of EIOB due to circulatory dysfunction are seldom reported.

METHODSThis retrospective analysis of symptom-limited maximum CPET data with an increment of 10-20 W/min in 38 patients with CHF. We calculated the duration, frequency, amplitude and other parameters of EIOB.

RESULTSThere were 31 presenting with EIOB (82%) in all patients with CHF. In EIOB group, VE amplitude were (12.4 ± 4.4)L/min (accounting for 81% ± 30% of mean) and duration were (77.0 ± 20.0)s. The number of patients whose EIOB presenting at rest, exercise, recovery stage and the whole eriod were 24, 31, 4 and 4, respectively. Except VE, there were VO2, VCO2, RER and PETO2 presenting EIOB in all 31 patients; VE/VCO2, VO2/VE and breath frequency in 29 patients; PETCO2 in 26 patients; VT and VO2/HR in 25 patients; and HR in 2 patients.

CONCLUSIONEIOB may occur in any period of CPET, mostly in severe patient with CHF, and presenting in many variables. Due to it is resulted from the circulatory dysfunction, we should call it circulatory (cardiac) oscillatory breathing abnormality.

Exercise Test ; Heart Failure ; physiopathology ; Humans ; Oxygen Consumption ; Respiratory Physiological Phenomena ; Retrospective Studies

Surgery remains the main stay in the treatment of carcinoma of the esophagus and the results of surgery for esophageal cancer have improved over the past 10 years. The ideal operation for cancer of the esophagus should have good palliation, low morbidity and mortality, and optimize both long-term function and survival. The two main approaches currently used for surgical treatment of esophageal cancer are: transthoracic esophagectomy (TTE) and transhiatal esophagectomy(THE). The advantages of THE are low morbidity and mortality, short operating time, a short hospital stay and low interference with respiratory physiology. The selection criteria for this procedure may differ but there are two situations which could clearly benefit from THE; these are epithelial and superficial submucosal lesions, particularly in cases of multiple lesions, and any resectable tumor at any stage with poor clinical status. I reviewed the selection criteria, surgical procedures, and results of THE in esophageal cancer with the literatures.
Esophageal Neoplasms* ; Esophagectomy* ; Esophagus ; Length of Stay ; Mortality ; Patient Selection ; Respiratory Physiological Phenomena

PURPOSE: Neonatal pulmonary function test(PFT) adds a new dimension to the understanding and care of the infant at risk for lung dysfunction. PFT can be identified the risk for pulmonary problems and safely and effectively diagnosed, quantified, and qualified the dysfunction. So it is possible to early institution of prophylatic respiratory therapy in such neonates and it can improved the dysfunction or reduce the incidence of both acute aand chronic complications. The purpose of this present study was to get the normal values of pulmonary function test in normal neonates METHODS: We evaluated 332 normal neonates at Ewha Womans University Hospital from Feb. 1994 to Oct. 1994. We performed PFT by tidal breathing flow-volume loop and non-invasive passive expiratory flow-volume technique. RESULTS: 1) The mean respiratory rate was 51.0+/-12.0/min and tidal volume 7.4+/-2.9 ml/kg. 2) In the tidal breathing pattern, %V PTEF was 0.42+/-0.17, PTEF/TV 2.36+/-0.76, TEF25/PTEF 0.80+/-0.10 and ME/MI 0.89+/-0.25, and the shape of loop was oval. 3) The mean respiratory system compliance by passive expiratory flow-volume technique in normal neonates was 1.52+/-0.93ml/cmH2O/kg and resistance 0.052+/-0.039 cmH2O/ml/sec. 4) The values of PFT were not different according to sex or postnatal age(p>0.05). CONCLUSIONS: The measured values of pulmonary function test in normal neonates could be used in the future as reference values of pulmonary function in neonates with variable respiratory diseases, and could be aid in understanding the respiratory physiology and pathology of neonates through companing the measured values of pulmonary function by other method.
Compliance ; Female ; Humans ; Incidence ; Infant ; Infant, Newborn* ; Lung ; Pathology ; Reference Values ; Respiration ; Respiratory Function Tests* ; Respiratory Physiological Phenomena ; Respiratory Rate ; Respiratory System ; Respiratory Therapy ; Tidal Volume

Arachidonic acid (AA) in the cell membrane produces a variety of metabolites by different enzymatic pathways. These lipid metabolites, along with other mediators, play an important role in the inflammatory processes. Many of them can bind directly to the receptors on the sensory endings and initiate electrical impulses to be transmitted to the central nervous system, causing reflex responses. These bioactive AA metabolites may also alter the lung mechanics (mechanical environment of the sensory ending), and in turn, stimulate sensory afferents. In addition, some metabolites may sensitize the sensory endings and make them more responsive to other mechanical or chemical stimulation. These metabolites may also induce other mediators and modulators to cause physiological effects. Furthermore, some of them may attract inflammatory cells to produce a localized effect. In short, AA metabolites may come from different sources and act through multiple pathways to stimulate airway sensors. This brief review is intended to illustrate the underlying mechanisms and help elucidate the inflammatory process in the airways.
Animals ; Arachidonic Acid ; metabolism ; Humans ; Inflammation ; physiopathology ; Respiratory Physiological Phenomena ; Respiratory System ; metabolism ; Sensory Receptor Cells ; physiology ; Vagus Nerve ; physiology

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