Biomedical subjects

M C Zoia

Publications and source records attributed to M C Zoia.

33 records · Page 2Linked to original sources

PubMed1993

Sleep related breathing patterns in patients with spinal muscular atrophy.

A clinical and polygraphic study of nocturnal sleep was performed in 8 (4 males, 4 females; age range 10-37 years) patients with spinal muscular atrophy, whose baseline respiratory function assessment during wakefulness showed restrictive ventilatory syndrome but blood-gas tension within normal limits. No patient reported any significant sleep complaint suggestive of sleep-disordered breathing. However, in 4 patients HbSaO2 desaturations below 90% (HbSaO2 nadir 68%) were detected during nocturnal polysomnography. The HbSaO2 desaturations occurred during brief central apneas or hypopneas, mainly during REM sleep, the apnoea hypopnea index being within normal limits in all cases. The data suggest that nocturnal polysomnography can detect otherwise clinically silent hypoxemia in SMA patients without any predisposing factor to sleep-disordered breathing other than their illness and still showing normal blood-gas tensions during wakefulness. Further studies are needed to determine the long-term evolution and the prognostic significance of nocturnal hypoxemia in these patients.

Adolescent↗

PubMed1993

Sleep disorders in neuromuscular diseases.

This article reports the results of several studies on neuromuscular patients (9 Duchenne's muscular dystrophy, 10 myotonic muscular dystrophy, 8 mitochondrial myopathies, 6 spinal muscular atrophy). An evaluation of respiratory function during wakefulness, a sleep questionnaire and an overnight polysomnography were performed in all patients. Recurrent hypoxaemia of variable degree was observed during sleep. In most cases, night-time hypoxaemia appears not to be predictable during wakefulness. Nocturnal hypoxaemia occurs in relation to apnoeas or hypopnoeas, mainly of central type, especially when these breathing irregularities occur during rapid eye movement (REM) sleep. Moreover, polygraphic sleep-apnoea patterns, as defined by international criteria, seem to be an infrequent condition, except for those neuromuscular diseases, characterized by an involvement of the central nervous system.

Adolescent↗

PubMed1993

Respiratory function in precapillary pulmonary hypertension.

Since dyspnoea on exertion is very often the first symptom of precapillary pulmonary hypertension (PPH), either from chronic thromboembolic pulmonary hypertension (CTEPH) or from idiopathic pulmonary hypertension (IPH), these patients are often first examined in a pulmonary function laboratory. We carried out a retrospective study (1987-1992) on pulmonary function in 34 patients diagnosed to have PPH by means of specific diagnostic tools, out of 5,467 patients first attending our laboratory. Nine suffered from IPH, 10 from CTEPH and 15 from Eisenmenger physiology. This last group differed from the others, since its diagnosis had been known for a long time and the stage of the disease was more advanced, when pulmonary function tests were performed in our laboratory (with a view to transplantation). Respiratory function, blood gases and arterial oxyhaemoglobin saturation (HbSaO2) during exercise (Bruce protocol), diffusing capacity of the lungs for carbon monoxide (DLCO), shunt fraction (QS%) (approximation obtained from arterial oxygen tension (PaO2) after 100% oxygen breathing) had been evaluated. In the first two groups, in contrast to other reports, we could observe no obstructive defect. Only 20% of the subjects had restrictive defects, however mild. The typical functional picture of these patients revealed normal lung volumes, normal or slightly reduced DLCO, mild hypoxaemia with hypocapnia, severe HbSaO2 drops during exercise, and pathological QS%. We conclude that every time a patient presents with breathlessness at rest or on exercise, a normal chest X-ray and respiratory function tests, pulmonary hypertension must be suspected and subject to specific and invasive tests. More severe functional impairment was observed in the PPH from the Eisenmenger disorder. This might be due to a more advanced stage of this type of hypertension at the time of our observation and/or to the different mechanisms of the diseases themselves.

Adult↗

PubMed1992

Reference values of maximal respiratory mouth pressures: a population-based study.

The aim of our study was to measure values of maximal inspiratory (MIP) and expiratory (MEP) mouth pressures in 625 (266 male, 359 female) clinically and functionally normal subjects drawn out of a sample representative of the general population. MEP (near TLC and FRC) was found to be significantly higher when compared with MIP (near RV and FRC), and pressures in male subjects were significantly higher than those in female subjects. MEP values at TLC and FRC were found to be closely related, as were values of MIP near RV and near FRC. Among the tested body-size variables, body surface area (BSA) for all parameters had the highest degree of correlation. Stepwise linear regression analysis was performed to define the equation of normality for all four parameters, employing BSA, sex, age, and relative interaction terms. R2 values, although the variables employed for the equations were highly significant, were relatively low and didn't fully explain the source of variability. The influence of age was smaller than the influence of BSA, although age did reduce the unexplained variance in MEP and MIP. These results confirm that the most useful employment of MIP and MEP is to monitor their changes in each patient, but they point out, however, the usefulness of reliable reference equations.

Adolescent↗

PubMed1992

Pulmonary function in childhood connective tissue diseases.

The term connective tissue diseases (CTD) defines a group of illnesses characterized by the presence of immune abnormalities and by widespread inflammation involving various organs and tissues including the lung. These diseases are not frequent in the paediatric age group. Very few data on pulmonary function are available in paediatric CTD. We investigated possible early lung function abnormalities and any likely relationship with clinical activity of the disease in a group of 81 paediatric CTD patients, without clinical or radiological evidence of pulmonary involvement. Measurement of lung volumes and diffusion lung capacity were performed. A sample of 65 subjects, defined as normal on the basis of history and clinical examination, and matched by age and height with the group of patients, was chosen as control group. CTD patients did not show significant deviations from the control distribution with respect to functional residual capacity (FRC) and maximal expiratory flow at 75% of the forced vital capacity (MEF75) values. On the contrary, both vital capacity (VC) and diffusing capacity of the lungs for carbon monoxide (DLCO) were quite impaired in most CTD during the active phase of the disease. Our results show a functional lung impairment in most children with clinically active CTD, even in absence of abnormalities on chest X-ray pictures.

Adolescent↗

PubMed1991

Nocturnal sleep and oxygen balance in Duchenne muscular dystrophy. A clinical and polygraphic 2-year follow-up study.

A long-term, clinical and polygraphic investigation of nocturnal sleep was performed in nine non-ambulatory Duchenne muscular dystrophy patients (mean age 16.2 years, range 10-20) with normal daytime blood gas tensions. The data show that nocturnal sleep has some adverse influence on oxygen balance in these patients as suggested by the occurrence of arterial oxyhaemoglobin desaturation occurring mainly during REM stages. This adverse effect tended to worsen significantly within a 2-year period in the absence of any sleep-related symptoms. A significant correlation between the degree of oxygen imbalance during sleep and the degree of restrictive thoracic syndrome during wakefulness was shown.

Adolescent↗

PubMed1989

Breathing patterns and HbSaO2 changes during nocturnal sleep in patients with Duchenne muscular dystrophy.

A night-time polygraphic sleep recording with continuous HbSaO2 monitoring was performed in 11 chair-bound Duchenne muscular dystrophy patients with severe restrictive lung disease but with blood gas values within normal limits when awake. No abnormalities of sleep pattern were detected. Nocturnal sleep did not have significant adverse effects on respiration. However, in 6 patients, infrequent central apnoeas or hypopnoeas occurred which were associated with falls in HbSaO2 greater than those that have been reported to be in normal subjects. The magnitude of HbSaO2 falls appeared to be significantly correlated with functional residual capacity values. Overall, the findings revealed a relatively preserved, although unstable, blood O2 balance during nocturnal NREM and REM sleep in patients with Duchenne muscular dystrophy, even in an advanced stage of their illness.

Adolescent↗

PubMed1989

Smoking habit and bronchial reactivity in normal subjects. A population-based study.

The relationship between smoking habits and airway responsiveness has been studied in a cross-sectional sample of subjects in a small Lombardy (Italy) town. The subjects were between 15 and 64 yr of age; they were representative of the general population. There were 295 normal nonsmokers, 70 normal smokers, and 50 past smokers. All clinically asymptomatic and functionally normal subjects underwent methacholine challenge. The distribution of responsiveness to methacholine (as expressed by LnPD15FEV1) was found to be significantly different between these normal smokers and nonsmokers. A multinomial logistic regression model showed a statistically significant difference in the response to the challenge on the basis of pack-years. When the number of years of smoking and the daily number of cigarettes were separately considered, the current amount had the significant correlation with LnPD15FEV1. Bronchial reactivity for past smokers was found not to be different from that for normal nonsmokers. We conclude that smoking habits, especially current habits, affect bronchial reactivity even in the absence of airway obstruction.

Adolescent↗

PubMed1989

Bronchial responsiveness to inhaled methacholine in epidemiological studies: comparison of different indices.

We evaluated the sensitivity and specificity of different indices drawn from the forced expiratory curve in order to detect the best one for evaluating bronchial reactivity in the general population, and particularly, for distinguishing between normal and asthmatic subjects. 654 subjects, between 15 and 64 years of age, who were representative for age and sex of the general population of a small Lombardy town (Italy), were studied. Of the total sample, 448 subjects were clinically normal and asymptomatic, 87 were symptomatic or with acute upper respiratory disease within 30 days before the challenge with methacholine, 43 with allergic rhinitis, 26 asthmatics and 50 chronic bronchitics. All the subjects who had a baseline FEV1 greater than 85% predicted underwent methacholine challenge. Provocative LnDoses of a 6, 10, 15% fall in FEV1 (LnPD6, LnPD10, LnPD15) and provocative LnDose causing FEV1 to fall more than 2 SD below the mean of 5 FEV1 measurements following buffer inhalation (LnTD) were evaluated. Furthermore we calculated the "Dose-Response slope" (SL) proposed by O'Connor. The cut-off value of each index to define a responder was calculated by discriminant analysis of the response to the challenge in normal and in the asthmatic group. Sensitivity, specificity and predictive value of LnPD6, LnTD and SL were 79, 74, 14%; 71, 74, 13% and 46, 97, 48% respectively. LnPD10 had the best sensitivity (83%) with a high specificity (83%), but, as compared to LnPD15, whose sensitivity was 79% and specificity 89%, a lower predictive value (21% vs 27%).(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

PubMed1988

Effects of celiprolol on the bronchial reactivity in asthma.

In 10 patients with bronchial asthma but normal ventilatory function, celiprolol, a cardioselective beta-adrenoreceptor antagonist, did not significantly affect forced expiratory volume in 1 second (FEV1) or airways resistance (Raw). In contrast, metoprolol substantially reduced FEV1 and increased Raw. In addition, compared with metoprolol, celiprolol induced a greater recovery of FEV1 and Raw after methacholine-induced bronchoconstriction.

Adrenergic beta-Antagonists↗

PubMed1988

Distribution of bronchial nonspecific reactivity in the general population.

We investigated 654 subjects of a small Lombardy (Italy) town between 15 and 64 years of age who were representative of the general population. By clinical examination, the sample included 535 normal subjects (164 normal smokers, 341 normal nonsmokers, 30 normal subjects with acute upper respiratory illness within 30 days before the challenge), 50 with chronic bronchitis, 26 with asthma, and 43 with allergic rhinitis. Subjects whose FEV1 was 75 percent or more than the predicted value (654) underwent methacholine bronchial challenge by means of 1 percent metered-dose solution. The test result was considered positive at a drop of more than 15 percent in FEV1 (compared with buffer). Normal smokers and all of the groups with disease had a significantly different distribution of reactivity compared with normal nonsmokers. The difference between asthmatic and these "normal" subjects was highly significant; nevertheless, a clear cut-off between the two groups does not appear to exist.

Acute Disease↗

PubMed1988

A comparison of the bronchodilator effects of broxaterol and salbutamol.

In 12 adult patients with reversible bronchospasm (7 bronchial asthma and 5 chronic obstructive bronchitis) the bronchodilator activity and tolerability of 200 and 400 mcg of broxaterol hydrochloride (Z 1170) were compared to those of 200 mcg of salbutamol administered by metered-dose inhaler. A single dose of the drugs was compared in a double-blind balanced latin square cross-over design. FEV1, FVC, MMEF, MEF25, heart rate and blood pressure were measured just before and 7.5, 15, 30, 60, 120, 180 and 240 min after each treatment. At these times clinical evaluation was also carried out to ascertain the presence of side effects. In the doses employed, broxaterol and salbutamol caused significant increases over baseline FEV1, MMEF and MEF25 from 7.5 to 240 min and FVC from 7.5 to 120 min. The difference between the effects of the two doses of broxaterol on FVC, MMEF and MEF25 was significant at 15 min. No significant difference was observed in the activity curves of 400 mcg of broxaterol and salbutamol. The effects of salbutamol were significantly greater than those of 200 mcg of broxaterol on FEV1 at 7.5 and 15 min and on FVC, MMEF and MEF25 at 15 min. All three treatments were well tolerated. No significant changes were observed in heart rate or blood pressure and tremors were not reported in any patient.

Administration, Inhalation↗

PubMed1987

Epidemiological diagnosis of asthma: methodological considerations of prevalence evaluation.

Within an epidemiological survey on Chronic Obstructive Pulmonary Disease, before reporting data on the prevalence of bronchial asthma we checked the group of subjects defined as "pathological" by means of a suitable questionnaire and a group of "normals" as a control. We evaluated the sensitivity and specificity of the questionnaire, in comparison with a clinical evaluation made by two physicians and controlled the relationship among their results, non-specific bronchial hyperreactivity and skin tests. In particular the correspondence between diagnosis made by physicians from a clinical evaluation and that obtained by questionnaire was not satisfactory. We suggest the importance of employing physicians for an epidemiological approach to asthma, in absence of a valid objective criterion.

Adolescent↗

PubMed1987

A clinical, EEG and CT study in 21 cases of chronic respiratory failure.

A clinical, EEG and CT study was carried out on 21 patients with chronic stable respiratory failure. The neurological disturbances and mental deterioration observed were of a mild degree, and no severe alterations were detected at EEG. CT showed cerebral atrophy, but the type and prevalence did not differ substantially between patients studied and normal sex- and age-matched control subjects. The data gave evidence that in chronic stable respiratory failure cerebral function is only slightly affected.

Aged↗

PubMedDate not supplied

[Cigarette smoke and bronchial hypersensitivity].

Among intrinsic factors which may affect the onset of COPD, bronchial non specific hyperresponsiveness seems to play an important, even though, ill-defined role. Attention is drawn to 2 major points: 1) Cigarette smoking habit may increase airway responsiveness? 2) Any possible hyperresponsiveness induced by smoking may be relevant in the development of COPD? At present, only point 1 may be positively answered; point 2 will be clarified by means of perspective and long-term surveys, we have not achieved yet. Our cross-sectional study showed a significant influence of smoking on bronchial responsiveness in absolutely asymptomatic subjects and with airway caliber absolutely in the normal range. This kind of influence resulted to be dose-dependent. Furthermore a noxious role of smoking has been observed, the greater effect the higher amount of cigarettes/day smoked. Moreover this acute role of smoking has been remarked by the trend of bronchial responsiveness of past-smokers, the more similar to non smoker's, the more far was smoking cessation.

Humans↗