Search PubMed⌕ Search

Biomedical subjects

R Sergysels

Publications and source records attributed to R Sergysels.

At least 91 records · Page 5Linked to original sources
PubMed1984

Assessment of the anaerobic threshold during exercise in normal man by means of the occlusion pressure as compared to conventional noninvasive techniques.

7 healthy men performed on a bicycle a stepwise increasing maximal exercise. During the work test the classical parameters usually used in the detection of the anaerobic threshold (AT) i.e. minute ventilation (VE), CO2 output (VCO2), O2 intake (VO2), gas exchange ratio (R) were recorded by a computerized system every minute. We also recorded the occlusion pressure (Po.1) in order to introduce it as a new parameter to detect the anaerobic threshold. Po.1 evolution showed a clear 'breaking point' at approximatively the same levels as for some of the other parameters (VE, VCO2). This 'breaking point' which is interpreted as the AT was also situated at the same level where VE/VO2 ratio increases without a change in VE/VCO2 ratio. Moreover the 'breaking point' separated the curves in linear and nonlinear increases as for VE and VCO2. By comparing the slope of the evolution of VCO2, VE, and Po.1 before and after the AT, it appeared that the easier visual detection of the AT was made by the Po.1 profile. We conclude that Po.1 is a valid index to detect the AT, and that this technique is a useful parameter in order to improve the visual detection of the AT.

Adult↗
PubMed1984

Comparative effects of SCH 1000 and fenoterol after histamine-induced bronchoconstriction in asymptomatic asthmatics.

In 16 asymptomatic asthmatics a functional study was carried out under controlled conditions during histamine bronchial provocation test (HBPT) and after bronchodilation test with either SCH 1000 or fenoterol by evaluating both SRAW and the slope of the alveolar plateau of nitrogen washout curve (N2 ph III). During HBPT, 9 of 16 subjects showed a central response (increase in RAW and SRAW only), whereas in the remaining 7 subjects histamine induced a mixed response due to an increase in both SRAW and N2 ph III. No differences between the two groups were observed in age and functional data during controlled conditions. Doses of delivered histamine were not significantly different. In 5 of 9 central responders to HBPT, SCH 1000 induced a decrease in SRAW only, whereas in 3 of the remaining 4 fenoterol caused both central and peripheral bronchodilation (decrease in both SRAW and N2 ph III). All mixed responders to HBPT showed a mixed bronchodilation during SCH 1000 (three subjects) or fenoterol (the remaining four). These data seem to indicate that the mechanism of bronchodilation induced by SCH 1000 is related to that of histamine-induced bronchoconstriction. Moreover, bronchodilation due to fenoterol could be related to a vagal modulation or be a systemic direct effect.

Adult↗
PubMed1984

[Chronic hypercapnia at rest or exercise-induced and ventilatory patterns in patients suffering from chronic obstructive bronchopulmonary disease].

The authors review the recent literature on hypercapnia at rest and on exertion in patients suffering from chronic airflow obstruction. At rest, the data in the literature has shown that for varying degrees of airflow obstruction, chronic hypercapnic patients show similar occlusion pressures to normocapnic patients. (The occlusion pressure is an index of the amplitude of neuro-muscular signals coming from the respiratory centre). However, their respiratory profile is characterised by a smaller tidal volume due to a reduction of the inspiratory time and often of a more rapid respiratory rate at a lower minute ventilation (VE). This pattern alone could explain CO2 retention by alveolar hypoventilation. On effort, various authors have shown that hypercapnic patients, or those becoming so during exercise, differ from normals by adopting a ventilatory pattern characterised by a reduction in ventilation linked to their airflow obstruction and a smaller tidal volume. The limited increase in tidal volume on effort is dependent on the duration of inspiration and the reduction of vital capacity and inspiratory capacity. As at rest, the two populations cannot be distinguished in terms of occlusion pressure.

Chronic Disease↗
PubMed1984

Effects of chronic aspirin ingestion in aspirin-intolerant asthmatic patients.

The effects of regular aspirin ingestion after aspirin-desensitization were evaluated in 10 aspirin-intolerant asthmatic patients. Chronic aspirin ingestion was not observed to be associated with either a significant improvement of mean FEV1 values or with a decrease in daily corticosteroid requirements. This study suggests that regular aspirin ingestion in aspirin-intolerant asthmatic patients does not induce a measurable improvement of the respiratory status.

Administration, Oral↗
PubMed1984

[Indications for the aspirin provocation test in the asthmatic].

Oral provocation tests using aspirin (n = 55), tartrazine (n = 37) and benzoate (n = 28) were performed in 55 asthmatic patients. A positive aspirin provocation test was observed in 15 patients (27%). These patients often had a past history of aspirin intolerance, 53% of them also had nasal polyposis and 5 out of 12 had associated tartrazine intolerance, while 2 out of 8 had associated benzoate intolerance. The authors consider that these features may help the clinician to detect the asthmatic patient at high risk of aspirin intolerance in whom a provocation test should be performed.

Adult↗
PubMed1984

Rapidly fatal bronchiolitis obliterans with circulating antinuclear and rheumatoid factors.

A 57-year-old woman developed severe bronchiolitis obliterans and presented circulating antinuclear and rheumatoid factors without any evidence of connective tissue disease. The evolution was rapidly fatal despite corticosteroid therapy and immunosuppressive treatment. The post-mortem study disclosed no connective tissue disease lesions. We suggest that the serologic abnormalities could be secondary to the inflammation of the bronchioles.

Antibodies, Antinuclear↗
PubMed1984

Decreased sensitivity to tartrazine after aspirin desensitization in an asthmatic patient intolerant to both aspirin and tartrazine.

An aspirin- and tartrazine-sensitive asthmatic patient underwent a desensitization to the adverse effects of aspirin by oral aspirin challenges. After a month of daily aspirin ingestion, the patient's reactivity to tartrazine, tested by oral challenge, was observed to the blunted. This report suggests that desensitization to the adverse effects of aspirin might protect the patient against the adverse effects of tartrazine.

Adult↗
PubMed1983

Effect of fenoterol on small airways and regional lung function in asymptomatic asthma.

Lung function tests for small airways were performed before and after inhalation of fenoterol by 11 young asymptomatic asthmatics and in 8 control subjects. In the asthmatics, minimal impairment in the tests was found except for increased expansion of the lower part of the lung (133Xe regional lung volumes) and an "abnormal" distribution pattern of a bolus of Xe inhaled from the residual volume. This suggests enhanced airway closure, especially in the lower area of the lung. Usual therapeutic doses of fenoterol (0.4 to 0.6 mg in puffs) could not correct these abnormalities, but 1.2 mg given to 2 patients resulted in changes similar to those observed in normals. The results suggest that small airway impairment in asymptomatic asthmatics is not only related to enhanced bronchomotor tone, but also to anatomical changes located especially at the base of the lung.

Adult↗
PubMed1983

Control of breathing during exercise in patients with chronic airflow limitation with or without hypercapnia.

Twenty-four patients suffering from chronic obstructive pulmonary disease (COPD) exercised on a bicycle with a progressive increase in load (30 W/min) until dyspnea or exhaustion occurred. Seven subjects were CO2 retainers: PaCO2 greater than or equal to 45 mm Hg at rest and/or during exercise. Fifteen normal subjects were submitted to the same protocol. To make comparison possible, all the parameters studied were calculated at 60 watts. It was concluded that CO2 retention during exercise is not secondary to a decreased respiratory drive but mainly to a lesser increase in VE and to higher VD/VT ratios.

Adult↗
PubMed1983

[Can respiratory kinesitherapy palliate the functional sequelae of chronic obstructive bronchopathies?].

Certain physiotherapy techniques can actively contribute to alter the functional consequences of chronic airflow obstruction (hyperinflation, respiratory rhythm and limitation of expiratory flow). Postural drainage does not seem useful until the secretions exceed 30 ml/24 hours. A search for a comfortable body position will no doubt offer mechanical and/or muscular advantages to the patient's breathing. Expiration with pursed lips slows the respiratory rate and limits airway collapse on expiration. Breathing at low frequency improves gas exchange but increases muscular work particularly if the physiological end tidal volume is exceeded. The rules of respiratory physiotherapists should in practice be modified to suit each individual patient.

Humans↗
PubMed1982

Site of action of inhaled histamine in asymptomatic asthmatic patients.

Histamine inhalation provocation-tests were performed in twenty-two young asthmatics with normal lung-function tests with progressive, increasing doses of a pressurized aerosol of histamine phosphate. Airway resistances (Raw) and N2 washout-curves were recorded. Two different types of response have been observed: (1) in thirteen cases, there was an increase of both Raw and the N2 phase III slope; and (2) in eight cases, there was only an increase in Raw (in one subject there was an increase in the N2 phase III slope only). Comparing the two groups of patients there was no difference in the inhalation procedure, the dose of histamine delivered or the smoking habits and lung-function data, except a slightly higher residual volume/total lung capacity (RV/TLC) ratio in the first group. The histamine-induced changes could not be related to any of the control lung-function data. We conclude that histamine inhalation may induce either peripheral bronchoconstriction only, or central bronchoconstriction with or without peripheral bronchoconstriction. A local and/or peripheral vagal-mediated bronchoconstrictor effect could account for the different site of airway response.

Adult↗
PubMed1982

Lung mechanics after aerosol and intravenous SCH 1000 in normal humans.

A functional study was carried out in six normal subjects before and after 0.5 mg of an intravenous atropine congener (SCH 1000) by evaluating the following parameters: static pulmonary volumes, resistance of the airways (Raw), N2 closing volume/vital capacity ratio, maximal expiratory flow volume, and the pressure-volume curves. From these curves we calculated the maximum flow-static recoil curves and the resistance of the airways upstream from the equal pressure point (Rus). On the following day four of six subjects inhaled 6 puffs (240 micrograms) of aerosolized SCH 1000 and the same parameters were evaluated. Both procedures caused a significant increase in maximum expiratory flow and a decrease in Raw. However, only intravenous SCH 1000 caused an increase in lung compliance and a decrease in Rus. When compared with previous data, our results show no dose-response effect on the atropine-induced modifications of pulmonary mechanics, and thus confirm the exclusive central bronchodilator effect of the aerosolized SCH 1000.

Adult↗