Biomedical subjects
Publications and source records attributed to R Sergysels.
Pulmonary function tests, at rest and during exercise, were performed in nine patients with metastatic carcinoma to the lung. The results are compared to the usual characteristics of diffuse interstitial fibrosis. Differences also occur between the pure multiple metastases pattern and the lymphangitic one. Literature on this topic is reviewed.
Twenty patients suffering from chronic obstructive bronchopulmonary disease were tested during exercise. If exhaustive load is always reduced; it is difficult to predict from the functional results obtained at rest. The commun characteristic found in those patients is the insufficient adaptation during exercise of the VA/V ratio, with deterioration of Pao2 and Paco2. Acidosis is constant and mixed both metabolic and respiratory. The results are discussed after review of the literature.
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Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
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Twenty-six coal miners, without associated functional chronic obstructive lung disease (COLD), assessed by normal airway resistance, were divided into three groups: (1) Group C, normal X-ray; (2) Group S1, micronodular silicosis; and (3) Group S2, complicated silicosis. All subjects were evaluated while at rest and during exercise. Significant lung volume reduction was observed in the S2 Group only. Blood gases, pulmonary pressure, and cardiac output were found to be within the normal range for all three groups when at rest. The pulmonary pressure and pulmonary vascular resistance were higher, however, for the S1 and S2 Groups when compared to the C Group. During exercise, pulmonary hypertension was observed in 50% of teh patients with complicated silicosis. When all data (N = 26) were included, the high values for pulmonary pressure and pulmonary vascular resistance correlated well with the loss in vital capacity (VC) and the decrease in forced expiratory volume in 1 sec (FEV 1.0). From the initial 26 patients, 19 were selected on the basis of their normal airway resistance and FEV 1.0/VC ratio. This selection did not alter the differences noted for the pulmonary pressure and total pulmonary vascular resistance, which previously existed between the groups, even though the correlations were not statistically significant. We conclude that silicosis without associated COLD leads to mineral hemodynamic impairment at rest and during exercise, and that airway resistance does not detect impairment of flow as effectively as FEV 1.0 reduction. The increased pulmonary vascular resistance observed, especially in complicated silicosis, may be best explained by the loss of lung parenchyma and possible impairment of small airways.
We compared airway resistances (Raw, body plethysmograph) and total pulmonary resistance at 4 and 24 Hz (RRS 4 Hz, 24 Hz) as well as the resonant frequency (RF), both in normals and in patients with airway obstruction. Bronchodilatation (n = 38) was the best evaluated by the induced changes in RRS 4 Hz and RF. However, the importance of change of RRS 4 Hz was poorly correlated with the change in Raw. Bronchial challenge test with histamine and DPT was again the best evaluated by RRS 4 Hz and RF with maximal changes observed for the latter. Normal ranges for Raw, RRS 4 Hz and RF were computed (n = 41). For all patients studied (n = 42) concordance for abnormality was good but poor for normality. From this we conclude that the oscillation technique is a different approach for the evaluation of airway obstruction and that RRS 4 Hz or RF are easy and accurate measurements to follow during bronchodilatation and bronchoconstriction tests.
In 11 patients suffering from chronic obstructive lung disease, thoracoabdominal movements were monitored with magnetometers during various breathing manoeuvres directed by the chest physiotherapist. The signals derived from the magnetometers and the mouth flow were analysed in order to pick up paradoxical movements of one or the other compartment of the chest wall. In contrast to what was observed during spontaneous breathing, especially abdominodiaphragmatic breathing induced in most of the subjects paradoxical movements. The practical importance of accurate monitoring of thoracoabdominal motion during chest physiotherapy is stressed.
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BACKGROUND AND AIM: The aim of the study was to re-examine the occlusion pressure measured simultaneously in the mouth (P0.1) and the oesophagus (Poes.1) during exercise in normal subjects submitted to different gas mixtures. METHODS: 7 healthy men breathing random gas mixtures containing 21% oxygen with either by 79% helium (He-O2) or sulphur hexafluoride (SF6-O2) and room-air, were studied during a steady-state 90w exercise performed on a cyclo-ergometer. Ventilatory parameters were derived from the flow signal recorded by a pneumotachograph calibrated with the different gas mixtures. Three pressure transducers (mouth, eosophageal and gastric) were checked to have iso-time identical responses up to 4Hz. P0.1, Poes.1, deltaPoes (difference in oesophageal pressure between end-inspiratory and end-expiratory levels) and deltaPdi (variation of transdiaphragmatic pressure between end-inspiratory and end-expiratory levels) were measured. RESULTS: Hyperventilation associated with a similar deltaPoes/deltaPdi but a lower P0.1/deltaPdi ratio was observed in He-O2 breathing compared to SF6-O2 and air. Variable time delays between oesophageal and mouth pressures were observed during air and SF6-O2. Whatever the condition involved, no change was detected in the shape of the inspiratory pressure during the occlusion manoeuvres. CONCLUSIONS: He-O2 breathing probably induced a change in the shape of the pressure wave later on in the inspiratory phase, making P0.1 not representing the total inspiratory drive. On the contrary in air and SF6-O2 conditions, P0.1 seemed to remain a useful tool for looking at the output of the respiratory controller.
One of the most important characteristics of asthma is its association with non specific bronchial hyperresponsiveness. This is diagnosed by histamine bronchial challenge tests. This latter is an easy procedure but requires a precise and standardized methodology. We have analysed, in a large group of bronchial challenge tests (n = 162) the clinical correlations with bronchial response to histamine. Our conclusions are in agreement with several recent literature, and may be summarised as follows: 1. more than 10% of patients, clinically considered as asthmatics do not show bronchial hyperresponsiveness and probably will not benefit from bronchodilators; 2. several aspecific respiratory symptoms (cough, chest tightness, blocked nose and sneezing, recurrent bronchitis, etc...) are frequently associated with bronchial hyperresponsiveness and should be considered as asthmatic manifestations. To conclude, we recommend to realise a histamine non specific challenge test in all cases of clinical suspicion of asthma (with normal lung function at basal state) and in all subjects presenting chest symptoms of uncertain etiology.
In order to deprive vagal upper and large airway receptors, an aerosol of 4% lidocaine (240 mg) was delivered to eight normal subjects and to eight eucapnic patients with chronic obstructive pulmonary disease (COPD). After this procedure, gag reflex (mechanical irritation of the larynx) and cough reflex tested by an aerosol of 10% citric acid were absent in all subjects. The anaesthesia was tolerated well by all the subjects and did not influence baseline pulmonary function tests. Moreover, during exercise, before and after lidocaine, no significant difference in O2 intake (VO2) or in blood gases (measured in patients only) could be observed. After lidocaine administration, no significant changes were seen in any of the respiratory variables studied in normal subjects or in COPD patients compared to the basal conditions. This could indicate that vagal upper and large airway receptors do not play an important role for the breathing pattern and ventilatory drive during exercise either in normal subjects or eucapnic patients with COPD.