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M G Cosio

Publications and source records attributed to M G Cosio.

65 records · Page 4Linked to original sources
PubMed1984

Involvement of upper-airway muscles in extrapyramidal disorders. A cause of airflow limitation.

To identify the site and cause of airflow limitation in patients with parkinsonism, we tested pulmonary function in 27 patients with extrapyramidal disorders. In 24 patients, an abnormal flow-volume loop contour, showing either regular (18 patients) or irregular (6 patients) flow oscillations, was found. On direct fiberoptic visualization of the upper airway, these oscillations corresponded to either rhythmic (4 to 8 Hz) or irregular involuntary movements of glottic and supraglottic structures. Ten patients had physiologic evidence of upper-airway obstruction, which was symptomatic in four. We conclude that the upper-airway musculature is frequently involved in extrapyramidal disorders. This causes upper-airway dysfunction that can be severe enough to limit airflow.

Aged↗
PubMed1984

Clinical applications of high-frequency jet ventilation.

Six patients with acute respiratory failure were treated with high-frequency jet ventilation (HFJV): 3 because they developed barotrauma while on conventional mechanical ventilation (CMV), 2 because of sedative- or PEEP-induced hypotension on CMV, and 1 because of bronchopleural fistula. In all patients, except the one with bronchopleural fistula, who was treated from the start with HFJV, gas exchange before (while on CMV) and after institution of HFJV could be compared. In these five patients, including the two with acute respiratory failure not complicated by barotrauma, gas exchange was better during HFJV than during CMV for the same levels of FIO2 and PEEP. HFJV therefore seems the method of choice for ventilatory support, not only in patients with bronchopulmonary disruption, but also in patients with hemodynamic embarrassment during CMV.

Adult↗
PubMed1980

Morphologic and morphometric effects of prolonged cigarette smoking on the small airways.

We studied lungs from 25 smokers and 14 lifelong nonsmokers, all over 40 yr of age, to examine the relationship of long-term cigarette smoking to histopathologic changes in the small airways. Despite considerable overlap between the 2 groups, smokers had a significantly higher score (p < 0.01) for small airway disease. The specific morphologic features separating smokers from nonsmokers were increases in goblet cell metaplasia (p < 0.001), smooth muscle hypertrophy (p < 0.05), inflammation in the walls of bronchioles (p < 0.01), and respiratory bronchiolitis (p < 0.001). The average bronchiolar diameter was not significantly different in smokers compared with nonsmokers; however, smokers had an excess of airways less than 400 microns in diameter (p < 0.03). Among smokers, the severity of small airway disease correlated with the percentage of airways that are less than 400 microns in diameter (rs = 0.63) and with the extent of centrilobular emphysema (r = 0.53). Smokers also had an increase in the proportion of bronchial gland mass (p < 0.05), but this pathologic feature was not related to the severity of either small airway disease or centrilobular emphysema. We concluded that prolonged cigarette smoking is associated with progressive pathologic changes in the small airways that may be an important cause of airflow obstruction and that may predispose to the development of centrilobular emphysema.

Adult↗
PubMed1980

Morphologic changes in the muscular pulmonary arteries: relationship to cigarette smoking, airway disease, and emphysema.

The muscular pulmonary arteries were studied by morphometric methods in 25 long-term cigarette smokers and were compared with those of 14 lifelong nonsmokers. Muscular pulmonary arteries < 500 microns in external diameter were identified and counted. The external diameter, medial thickness, and intimal thickness were measured in each of these arteries. Smokers had an increased number of transected muscular arteries < 200 microns in diameter (p < 0.03), increased medial smooth muscle (p < 0.02), and more intimal thickening (p < 0.04). Among smokers, these vascular changes correlated significantly with the severity of small airway disease and with the degree of emphysema, but not with bronchial mucous gland enlargement. We conclude that regular cigarette smoking is associated with morphologic changes in the muscular pulmonary arteries that evolve in parallel with small airway disease and emphysema. Although the functional significance of these findings is unknown, they may be important in the eventual development of pulmonary hypertension and cor pulmonale.

Adult↗
PubMedDate not supplied

Biochemical and morphological correlation of oxidant-induced pulmonary injury: low dose exposure to paraquat, oxygen, and ozone.

The authors compared the temporal pattern of low-dose oxidant-induced lung injury in rats after exposure to either 1 ppm ozone or 100% oxygen for 24 hr or from treatment with paraquat (20 mg/kg, intraperitoneally). Histological abnormalities in airways, parenchyma, and blood vessels were evaluated from coded and randomized sections and compared with appropriate controls. Drug metabolism by lung endoplasmic reticulum was studied in similarly treated rats as another index of lung injury. Exposure to oxygen caused no discernible morphological or biochemical abnormalities. Exposure to ozone caused histological lesions which appeared early and resolved by 7 to 14 days, whereas paraquat-induced lesions were first evident at about 7 to 14 days. Abnormalities in drug metabolism followed a similar pattern. Low-dose oxidant exposure from ozone and paraquat produce similar histological and biochemical lesions in rat lungs but with distinct temporal patterns.

Animals↗
PubMedDate not supplied

[Obstructive sleep apnea syndromes].

Obstructive sleep apnea syndrome was first described 200 years ago but the definition of the syndrome was only developed during the last ten years (snoring, apneas during the night, somnolence, high blood pressure, changes of personality). The frequency of the syndrome is not known exactly but the pathophysiology, the morbidity and the mortality associated with the syndrome is facilitating by application of a positive airway pressure (CPAP) at the nose. Good compliance and rapid improvement of the symptomatology with practically no complications make that CPAP is the first choice for the physician in 1991.

Clinical Protocols↗
PubMedDate not supplied

Maximal static respiratory pressures in adults: normal values and their relationship to determinants of respiratory function.

Assessment of respiratory muscle strength is done most directly by measuring maximal static inspiratory and expiratory mouth pressures (MIPS and MEPS, respectively). The available studies that report reference values of MIPS and MEPS, however, show ill-explained wide variability, not only between individuals but also between studies. This study of 106 normal white adults (60 women and 46 males, aged 16 to 79 yr) attempts to identify the anthropometric factors which best predict MIPS and MEPS. It was found that: 1) smoking does not affect MIPS and MEPS; 2) sex is a major determinant of MIPS and MEPS, as women reached 68 and 63%, respectively, of the male values; 3) within each sex, age is the major determinant of MIPS and MEPS, since body size factors such as height, weight and percent ideal body weight do not significantly improve the relationship between age and MIPS or MEPS. In both sexes, the pattern of change in pressures with age is different for MIPS and MEPS, suggesting different maturation processes for MIPS and MEPS. While MIPS is an inverse linear function of age (i.e. MIPS decreases with advancing age from early adulthood on), the relationship between MEPS and age is best described by a second degree polynomial (i.e. MEPS increases towards a peak in mid-life, after which it also decreases with age).(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMedDate not supplied

Flow oscillations on the flow-volume loop: a nonspecific indicator of upper airway dysfunction.

Flow oscillations on flow-volume loops (a "saw-tooth" pattern) have been reported as a manifestation of obstructive sleep apnea (OSA), but the specificity of this flow-volume loop pattern has not been determined. In a review of 2800 flow-volume loops performed in our pulmonary function laboratory, we identified flow oscillations in 40 patients, an incidence of 1.43%. Thirty-one of these 40 patients (77%) did not have OSA. In 16 of these 31 patients (52%), a structural disorder of the upper airway or neurologic disease involving the upper airway muscles was found. Flow oscillations were associated with physiological upper airway obstruction (UAO) in 14 of these 40 patients (35%), but were the only physiological evidence of upper airway dysfunction in the other 26 patients. Flow oscillations on flow-volume loops thus represent nonspecifically instability of the upper airway, caused by a variety of disorders, including OSA. Detection of this peculiar flow-volume loop configuration should lead to investigation of the upper airway and the surrounding musculature as it might be an early indicator of ongoing disorders eventually leading to UAO.

Adult↗