Respiration; international review of thoracic diseases
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Comparative Study
Features of idiopathic pulmonary fibrosis with organizing pneumonia.
To characterize the clinical features of patients with idiopathic pulmonary fibrosis (IPF) having organizing pneumonia (OP), we retrospectively reviewed the clinical charts, chest X-rays, CT scans, and transbronchial lung biopsy (TBLB) specimens of patients with IPF. Patients with IPF and OP had a subacute onset of symptoms (within 2 months) (87.5%), leukocytosis (> 10,000/mm3) (62.5%), and a strong C-reactive protein (CRP) reaction (> 3+) (75%). Some of these features were distinctly different from those of IPF patients without OP (subacute onset of symptoms 0%, leukocytosis 0%, strong CRP reaction 16.7%). ⋯ Clinical features of IPF patients with OP differed from those of patients with IPF without OP. IPF patients with OP showed good clinical response to corticosteroid therapy. These findings warrant further study of the presence of OP in TBLB specimens in predicting corticosteroid responsiveness and prognosis of patients with IPF.
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We report 7 patients with severe acute asthma unresponsive to standard medication, including sympathomimetic agents, aminophylline and corticosteroids, who responded to inhaled frusemide. All were hypercapneic with a mean PaCO2 of 7.7 kPa (57.7 mm Hg) [range 6.2-8.8 kPa (46.2-66.3 mm Hg)]. ⋯ No adverse effect was recognized. Inhaled frusemide should be considered for treatment of acute asthma refractory to conventional therapy.
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Comparative Study Clinical Trial
Changes in arterial and transcutaneous oxygen and carbon dioxide tensions during and after voluntary hyperventilation.
The purposes of our study were (1) to investigate whether a 3-min short-term hyperventilation leads to posthyperventilatory hypoxemia and (2) to assess the role of transcutaneous blood gas measurements for monitoring oxygen and carbon dioxide changes during the after the test. In 10 male volunteers arterial and transcutaneous blood gases were measured simultaneously before, during and after a 3-min voluntary hyperventilation maneuver. Baseline arterial PO2 increased from 13.7 +/- 0.4 kPa (103 +/- 3 mm Hg) to 18.6 +/- 0.3 kPa (139 +/- 2.3 mm Hg; p < 0.005 compared to baseline) during hyperventilation. ⋯ A short-term over-breathing of 3 min causes a significant posthyperventilatory hypoxemia. We hypothesize that posthyperventilatory hypoxemia is caused by hypopnea as a result of depleted CO2 body stores. Noninvasive transcutaneous blood gas measurements are not reliable for monitoring blood gas changes during and after hyperventilation, most probably because of the slow response time of the electrodes and the reflex vasoconstriction of the skin vessels.
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Starling's law (the energy of muscle contraction is proportional to the initial fiber length) has been applied to contraction of inspiratory muscles. Its application to the expiratory muscles is difficult because both maximal length and maximal pressure development occur at total lung capacity (TLC). We hypothesize that decrease of both inspiratory (Pimax) and expiratory (Pemax) muscle strength in chronic ascites (CA) will reflect generalized muscle weakness and stretching of both the diaphragm and abdominal wall as well. ⋯ With fluid removal, abdominal muscles shortened; diaphragmatic curvature decreased although diaphragm length was unchanged. Nevertheless, neither Pimax nor Pemax increased. Respiratory muscle strength depends upon generalized muscle strength more so than upon muscle length in CA patients.
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The clinical utility of the newly developed pressure swing adsorption (PSA)-type oxygen concentrator with a membrane humidifier that does not require added water for humidification was evaluated in 13 patients with chronic pulmonary disease who were receiving long-term oxygen therapy. PaO2 and the relative humidity were measured when the patient breathed air and oxygen from the new device via a nasal cannula. After using the new concentrator for 5 h, the patients were asked whether they experienced dry nasal passages or a dry throat. ⋯ A significant difference was observed between the relative humidity of room air (44.7 +/- 18.6%) and that of the oxygen flow (72.7 +/- 14.8%) from the new device. None of the patients experienced dry nasal passages, dry throat, or any other adverse effects. Since this new PSA-type oxygen concentrator with a membrane humidifier supplies well-humidified nasal oxygen without water, laborious cleaning of the container and changing of the water are not necessary, and may help to improve the patient's quality of life.