Respiration; international review of thoracic diseases
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A 49-year-old woman was admitted to the hospital for hypercapnia. Pulmonary function testing showed small lung volumes without parenchymal lung disease. ⋯ Finally, muscle biopsy revealed abundant nemaline bodies characteristic of nemaline myopathy. Nasal intermittent pressure ventilation was started with a preset pressure ventilator during sleeping hours with a good response.
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Review
Physical and functional properties of airway secretions in cystic fibrosis--therapeutic approaches.
The airway secretions which line the respiratory tract form a biphasic layer composed of an aqueous 'sol' layer and a more superficial 'gel' layer. In the sol layer, also described as the 'periciliary' layer or 'airway surface fluid', the cilia beat and relax. The lubricant sol layer enables the gel mucus present at the tips of the cilia to be transported by the ciliary beating of the ciliated cells. ⋯ In view of these alterations in the physical and functional properties of CF airway secretions, pharmacologic approaches should aim to rehydrate the mucus and to restore normal mucociliary or cough transport by stimulating chloride ion secretion (i.e. using UTP or ATP associated with amiloride in order to block sodium ion and water reabsorption). During acute episodes of infection, recombinant human DNase (rhDNase) may rapidly prevent mucus stasis by improving its rheologic properties. Lubrication of the mucus at the sol phase interface by 'surfactant' therapy may also represent a very promising therapeutic perspective to reduce the hyperviscosity and hyperadhesivity of airway secretions.
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Randomized Controlled Trial Clinical Trial
Lung function changes and exercise-induced ventilatory responses to external resistive loads in normal subjects.
The aim of this study was (1) to assess the value of common lung function variables in the follow-up of patients with obstructive lesions of the larynx and trachea and (2) to study the respiratory response to progressive upper airway stenosis at rest and during exercise. ⋯ It is suggested that the experimental use of inspiratory and expiratory extrinsic loads can mimic rigid obstructive lesions of the larynx and trachea. Among all conventional lung function values, PEF and, to a certain degree, PIF, seem to be the best suitable follow-up parameters to assess airway mechanics before and after surgical/endoscopic procedures. Upper airway stenosis involving surface areas of no more than 50 mm2 can be overcome using adequate respiratory compensation. But any additional narrowing below this limit will result in hypoventilation, inappropriate oxygen uptake and retention of CO2. Thus, experimental evidence indicates that laryngotracheal obstruction within a critical range below 50 mm2 surface area (diameter of circular orifice < 8 mm) compromises respiratory efforts enough to be of clinical importance.
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Case Reports
Long-term course of bronchiectasis and bronchiolitis obliterans as late complication of smoke inhalation.
We describe the long-term course of a patient with bronchiectasis and bronchiolitis obliterans, both of which developed as late complications of a smoke inhalation injury. Sequential chest X-rays obtained during the observation period showed gradual progression of bronchiectasis from the saccular to the cystic type. Symptoms, spirometry and blood gas analysis, however, remained stable for 15 years. We believe that symptoms and physiological derangement were due mainly to bronchiolitis obliterans, and that once the pathophysiological condition had been established following the initial injury, it could be maintained by conservative medical management.
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Airway disease in cystic fibrosis (CF) is characterized by neutrophil-dominated chronic inflammation with an excess of uninhibited neutrophil elastase (NE), which is regarded as an important factor in progressive lung destruction. Therefore, inhalation of alpha 1-proteinase inhibitor (alpha 1-PI) seems to be a reasonable therapeutic approach. To estimate its therapeutic potential, we quantitatively investigated the in vitro interactions of exogenous alpha 1-PI with CF sputum samples (n = 28). ⋯ Corresponding to inhibition of NE activity, CF sputum-induced secretion was also inhibited by exogenous alpha 1-PI; > 90% inhibition was also achieved at 10 micrograms/ml alpha 1-PI. Incubation of exogenous alpha 1-PI with CF sputum for 24 h did not reduce the inhibitory effects. From our in vitro results we conclude that inhalation of alpha 1-PI might effectively inhibit both NE activity and airway gland hypersecretion in CF airways.