Biomedical subjects

J Vogel

Publications and source records attributed to J Vogel.

At least 289 records · Page 16Linked to original sources

PubMed1976

[Computer analysis of mechanics of breathing by semi-on-line technique (author's transl)].

A program for the analysis of lung mechanics based on esophageal technique and running on mini-computer Cellatron 8205 is described. There are two varieties of analog-digital-conversion of primary flow- and pressure-signals from magnet tape storage to punch tape input channel using transposition of frequency either with sequential or alternating data collection oriented on respiratory half-cycles and unlimited in view of function test time. The program gives a complete status of lung mechanical parameters per respiratory half-cycle and total-cycle, that is pulmonary compliance, elastance, maximal resistance, minimal resistance, peak flow resistance, initial and terminal standard flow resistance, total, static and dynamic work of breathing, power of breathing. Output is provided both in writing and punching results to establish the connection with sequential high-level programs of lung mechanics and statistical data processing.

Computers↗

PubMed1976

[Generation and determination of pulmonary distribution disturbances (author's transl)].

Pulmonary distribution disturbances could be generated in patients with bronchial hyperreactivity by inhalation of a Falicain aerosol (Propoxipiperocainhydrochlorid); The inhomogeneities of ventilation and mechanics of breathing were determined by means of several simple and complex methods. Comparison between these methods of analysis of distribution shows that small alterations of inhomogeneity can be indicated also by simple screening tests. The results confirm the significant relationship between ventilation disturbance and pulmonary inhomogeneity. Distribution disturbance enhances both the obstructive and the restrictive component of a ventilation disturbance. These two components cannot be separated exactly by means of the parameters of ventilation and mechanics of breathing because of the influence of inhomogeneity. The generated disturbances of distribution and ventilation became regular after inhalation of an Alupent aerosol.

Aerosols↗

PubMed1976

[Results of comprehensive respiratory function tests in CNSLD (author's transl)].

34 persons with CNSLD, but fit for work, were examined with the aim to record the degree of disturbance of pulmonary function and the underlying pathophysiological mechanism. The results were compared with 30 healthy subjects. The following function tests were carried out under resting conditions and bicycle ergometer exercises: Analysis of ventilation (FVC% pred., FEV1% FVC, RV% pred., RV% TLC), analysis of lung mechanic (Raw, CL) measurement of diffusion (DL, DM, Vc, DL% pred.) and analysis of lung inhomogeneity (RE/REO, V2/V1, CL6/CL100, deltaFN2/deltaV500, deltaFCO2/deltaV500,IHB). The results were analyzed and evaluated by using the digital computer C 8205. Persons suffering from CNSLD were showing among typical clinical symptoms the following disturbances of lung function: The obstructive ventilation disturbance stands in the foreground in connection with signs of inhomogeneity of lung mechanics and ventilation. While the resistance already shows the airway obstruction objectively under resting conditions, the decreased compliance is measurable at first under exercise. The disturbance of diffusion, which is pointed out, is mainly a latent decreased diffusing capacity of alveolo-capillary membrane. These disturbance of diffusion gets more importance because the inhomogeneity of lung hides the real disturbance of diffusion. The pathophysiological consequence of disturbed partial functions of respiration is the latent hypoxaemia without hypercapnia, therefore the signs of respiratory partial insufficiency.

Adult↗

PubMed1976

[Comparison of lung-mechanical and physico-chemical Parameters in view of the pulmonary surfactant system (author's transl)].

Evaluation of static pressure-volume-diagram of lungs and of surface-tension-area-diagram of lung-elutions measured on the Lamgmuir-balance is tested. Well known parameters are used to characterize alveolar surfactant activity in guinea pigs after perbronchial application of extracorporal surfactant Tacholiquin and detergent "Fit" 1% and after application of vagomimetics Acetylcholine 1% and Histamine 0.1%. Mean values of physico-chemical parameters show the most significant increase of the area of hysteresis (Benzer) during Tacholiquin and Acetylcholin application; the minimal surface-tension: gamma min, and the compressibility-index: gamma min/delta gamma (Kötter, Rüffer) decreased, the difference between maximal and minimal surface-tension: delta gamma and the stability-index: 2 delta gamma/(gamma max + gamma min) (Clements) increased. Tacholiquin and Acetylcholin both improve pulmonary surface-activity. The Tacholiquin-effect is documented in lung mechanics only by elevation of the inspiratory volume-rations: V10I/V20I (Clements) and V10I/Vmax (Kittelmann) referred to static pressure 10, 20 cm H2O and maximal pressure but not by elevation of the expiratory stability index V10E/Vmax (Gruenwald). The area of hysteresis is decreased indicating a preponderant inspiratory effect. The Acteylcholin-effect is covered by the well-known bronchial obstructive effect. Both inspiratory constants are decreased, and the area of hysteresis is increased. We did not find any significance of the expiratory stability index. Both inspiratory constants and the area of hysteresis are conditional surfactant parameters in view of bronchial obstruction.

Acetylcholine↗

PubMed1976

[Functional analysis in experimental respiratory distress syndrome (author's transl)].

After injection of an anti-lung -serum a respiratory distress syndrome could be produced in spontaneously-breathing guinea pigs. Reduced compliance, increased resistance and work of breathing was found. Morphological investigations showed intraalveolar and interstitial bleedings and a lung edema. Biochemically a decreased total phospholipid content could be found. Surface tension characteristics, examined with the Langmuir balance, were deteriorated. A complete restitution of surface tension parameters and total phospholipid content was obtained by administration of bromhexin metabolit Na 872.

Animals↗

PubMed1976

[Further development of the program system for lung function diagnostics running on minicomputer C 8205 (author's transl)].

Starting from the level of 1972 the development is characterized in view of -- general technical, psychological and economical problems -- completion of the program library and the -- technique of semi-on-line data collection. The last point describes experiences using the system of VEB Funkwert Erfurt. Different levels of automatization in lung function labs are discussed.

Computers↗

PubMed1976

[Computer measurement of residual volume and alveolar gas distribution parameters in epidemiological studies (author's transl)].

Starting from the quick helium-rebreathing-technique of Kowalski-Visser a method of combined measurement of residual volume and closing volume in one test was developed using automatic data - collection in 3 different variants, that is- automatic control during test- manual control during test and- manual control on the table. A computer program running on minicomputer Cellatron 8205 is described. Experiences using the different program-variants are discussed.

Diagnosis, Computer-Assisted↗

PubMed1976

Models of respiratory insufficiency in view of lung function diagnostics and pathogenetic analysis (author's transl).

Organizing principles of lung function diagnostics and of research in the field of pathophysiology of respiratory insufficiency are developed starting from fundamental requirements, which are practical effectivity, scientific basement, technical development and teamwork of specialists in a complementary system. Technique of screening level, primary oriented of effectivity, is based on the simple monoalveolar model of ventilation. Basal lung function diagnostics, primary oriented on objectivity, representing the total of pulmonary impairment is based on the model of arterial hypoxemia. Condition and limitations of these models are discussed preparing its substitution by models of complex lung function analysis in the higher level diagnostic system.

Binding Sites↗

PubMed1976

[Experimental model of bronchial asthma (author's transl)].

Allergic asthma-like attacks were induced in guinea pigs by intraperitoneal injections of Ovalbumin and following inhalation of Ovalbumin aerosol. The animals were narcotized, tracheotomized and a small catheter was placed in mid-oesophagus. The quantities: oesophageal pressure, respiratory flow and tidal volume were measured and recorded on magnetic tape during spontaneous breathing. A technique was applied for automated computation of the parameters of respiratory mechanics using a digital computer. The parameters compliance, resistance, work of breathing and power of breathing showed typical pathological variances and characteristic response-curves in the experimental phases during and after the asthma attacks. These parameters became normal after the injection of Alupent.

Animals↗

PubMed1976

[Functional diagnosis of CNSLD in epidemiological surveys-results of the population study in Halle 1974 (author's transl)].

The problems of lung function testing methods in epidemiological studies were assessed in a study population of 853 men aged 40-70. The Helium-rebreathing-method, the X-ray densitometry, the oxygen-method were evaluated for the estimation of the residual volume in epidemiological conditions. The Pneumotest was proved for measurement of unequal ventilation. The necessity of reference values for these methods is discussed.

Adult↗

PubMed1976

[Basic-diagnostic-criterions of respiratory insufficiency--results of a community work of the working group "pathophysiology of breathing" (author's transl)].

11 laboratories of the working group "Pathophysiology of Breathing" cooperated with standardized methods to obtain generally admitted practical criterions for the definition of respiratory insufficiency. Function parameters of 2800 examined persons in different diagnostic groups were tested by manual statistical analysis and computed by data processing system. which were assessed with regard to their usefulness as criterions for respiratory insufficiency. The arterial O2-partial pressure proved to be the most crucial criterion of respiratory insufficiency permitting objective evidence of a manifest respiratory insufficiency by hypoxeamia under standard efforts with a bicycle-ergometer. The screening parameters of ventilation such as vital capacity and forced exspiratory volume are suitable as subjective rapid methods for a quantitative estimation of one type of respiratory insufficiency: the ventilation disturbance. Investigations, which were carried out with a higher apparatus expense like the estimation of residual volume, the functional residual capacity, and the arterial CO2-partial pressure permit the further differentiation of causes of the respiratory insufficiency and the separation between respiratory partial- and global insufficiency. The parameters of gas exchange: O2-consumption, respiratory quotient, and the screening parameter of cardiocirculation heart rate are not or only limited useful as criterions of respiratory insufficiency alone.

Hemodynamics↗

PubMed1976

[Automated analysis of changes in parameters of lung mechanics with alterations in breathing frequency, lung volume, and physical effort (author's transl)].

Changes in parameters of respiratory mechanics with alteration in breathing frequency, lung volume and physical effort were determined in 23 subjects using automated data collection and data processing. Resistance R, Compliance C and work of breathing W show great dependence on breathing frequency and lung volume. An objective measuring of their changes during exercise requires a constant lung volume and a standardized breathing frequency. Parameters R and C and the maximal pressure amplitude DPM divided by the tidal volume VT show no significant alterations in several degrees of exercise. Work of breathing and work of breathing per tidal volume are enhanced significantly with increasing exercise. These parameters may estimate the mechanics of breathing better than R and C in patients with dyspnea during exercise.

Automation↗

PubMed1975

[Rapid test for quantitative proof of emphysema].

For the purpose of an aimed diagnostics near to practice of unspecific chronic pulmonary diseases a measuring place was developed, by means of which with simple performance of the experiments and short examination-time the determination of vital capacity, forced expiratory volume, maximal breathing capacity, the measurement of the O2-tension of the arterialised ear blood and the determination of the residual volume are possible. The determination of the residual volume is performed according to the classical O2-N2-gasmixture method using the spirotest device in connection with a bag-box system and the PO2-micro-measuring chamber. On 63 patients the residual volume was determined in this measuring place and compared with the rapid He-re-breathing method. The correlation analysis between the RVbody%TK- and the RVO2% TK-values with a correlation coefficient r = 0,887 ascertains the reliability of the demonstrated method. The results of a epidemiological study on 422 test persons on account of the close correlation between RVHe % TK and RVO2% TK with r = 0.62 prove the usability for examinations of the population.

Airway Resistance↗

PubMed1975

[Screening tests for the determination of risk groups in respiratory insufficiency under conditions of epidemiological serial studies].

A report is given on a system of effective respiratory functional tests which proved its value when used in epidemiological mass examinations in connection with the mass miniature radiography in Berlin, Brandenburg and Halle as well as in mass examinations in Berlin enterprises. Thereby a new development - Pneumotest - is presented, an electronic spirometer for the recognition of ventilatory and distribution analytic preliminary parameters with digital indication of 5 sizes of the breath test manoeuvre which is to be applied as successor of the well-known spirotest device. In this paper the functional capacity of the further developed fluorographic densimetry as preliminary emphysematic test is proved. The application of the rapid helium or O2/N2 breathing back technique for the determination of residual volume and closing volume has in connection with the automatic establishment of the measuring values proved as basic diagnostics for emphysema with a large efficiency and at the same time with high reliability. The digestion of the epidemiological functional data with the help of electronic data processing is carried out in the own microcalculator system following immediately the application during examination.

Humans↗

PubMed1975