Search PubMed⌕ Search

Biomedical subjects

F Geubelle

Publications and source records attributed to F Geubelle.

At least 73 records · Page 4Linked to original sources

Bronchial inhalation challenge by plethysmography in asthmatic children.

A new technique for breath-by-breath controlled bronchial inhalation test is described, using the body plethysmographic method. The values of airway resistance (Raw) and of thoracic gas volume at resting expiratory level (TGV) have been compared to the data of total pulmonary flow resistance (R1), measured with the intraesophageal catheter method, and of functional residual capacity (FRC). The dynamic lung compliance (C1 dyn) was calcualted, too; the mechanical parameters of breathing (R1; Raw; C1 dyn) have been investigated on the same breathing cycles before, during and after respiratory challenges in symptom-free asthmatic children. Regarding the breath-to-breath variation of the parameters, a respiratory challenge is usually considered as positive, if the R1 or Raw values increase 100% or more. Out of 39 assays, "positive" challenges were observed in 14 casis regarding R1 values and in 11 cases regarding Raw values. "Doubtful" tests - i.e. +50% less than or equal to R1 or Raw less than 100% - were observed in 5 assays regarding R1 and in 7 cases regarding Raw. A decrease of more than 40% of C1 dyn was observed in 12 out of the 19 'positive' or 'doubtful-positive' challenges; the largest spontaneous breath-to-breath variation being +/- 25%. Such a decrease of C1 dyn is suggested as a sign of peripheral bronchial obstruction. An increase of more than 25% of TGV was observed in 11 out of 19 assays, considered "positive" or "doubtful-positive". A correlation being observed between C1 dyn decrease and TGV increase this latter parameter is suggested to be an additional sign of bronchial obstruction. Beside the practical problem of the interpretation of a respiratory challenge, these results are discussed from the phatophysiological point of view.

Adolescent↗

Static and dynamic lung compliance in asthmatic symptom-free children.

The static lung compliance was studied in 27 symptom-free asthmatic children, 6-14 years old. The technique of so-called end-expiratory compliance measurement as well as that of the 'zero volume' in the balloon at barometric pressure, used in this study, have been previously discussed. The static lung compliance value is larger than the dynamic lung compliance value, this difference being larger in asthmatic than in healthy children. This difference is explained by higher static lung compliance values in asthmatic than in healthy children, whereas dynamic lung compliance values are only slightly lower in the group of asthmatic patients compared to healthy children. Static lung compliance per unit of lung volume (specific static lung compliance) is identical in both groups. Static recoil pressure at 80% of total lung capacity (TLC) is similar in asthmatic and healthy children. However, in symptom-free asthmatic children with hyperinflated lungs [functional residual capacity (FRC) higher than 25% of predicted value and FRC/TLC ratio higher than 0.45], static recoil pressure at 80% TLC is lower than the predicted value, this difference being not significant.

Adolescent↗