American journal of respiratory and critical care medicine
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Am. J. Respir. Crit. Care Med. · Feb 1996
Randomized Controlled Trial Clinical TrialEfficacy of auto-CPAP in the treatment of obstructive sleep apnea/hypopnea syndrome.
The auto-CPAP (Morphée Plus) is characterized by its ability to modify the positive-pressure level applied during the night for the presence or absence of sleep-induced respiratory disorders. The aim of the study was to compare the efficacy of this new mode of CPAP therapy with that of conventional constant-CPAP in the treatment of sleep apnea/hypopnea syndrome (SAHS). Sixteen patients with SAHS were randomly allocated to two groups that were paired for age, apnea/hypopnea index, and mean sleep latency. ⋯ During the control CPAP sleep study, the positive pressure level was significantly lower during Stage III-IV than during the other sleep stages (p = 0.004). The improvement in the MWT and the TMT observed with CPAP therapy was identical in both groups. We conclude that (1) the amount of use during CPAP treatment is higher with auto-CPAP than with constant-CPAP, and (2) Morphée+auto-CPAP is an efficient as conventional CPAP in correcting nocturnal breathing disorders, daytime sleepiness, and cognitive impairment in SAHS.
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Am. J. Respir. Crit. Care Med. · Feb 1996
Hypothalamic-pituitary-adrenal axis in corticosteroid-resistant bronchial asthma.
We have examined whether the lack of clinical response to corticosteroids seen in corticosteroid resistant (CR) bronchial asthma is reflected in abnormalities of endogenous cortisol secretion and in the sensitivity of the hypothalamic-pituitary-adrenal (HPA) axis in CR subjects by using a modification of the standard dexamethasone suppression test (DST) in response to 0.25 and 1 mg oral dexamethasone. Five corticosteroid-sensitive (CS) and five CR asthmatic subjects were studied on two occasions 1 mo apart. In the first limb of the study subjects received 0.25 mg of oral dexamethasone, and in the second limb they received 1 mg. ⋯ The levels of urinary free cortisol (nmol/24 h) and predose plasma ACTH (ng/L) and cortisol (nmol/L) were 199 +/- 42, 27.4 +/- 5.7, and 300 +/- 48 (mean +/- SEM), respectively, in the CS group, and 210 +/- 74, 23.4 +/- 6.7, and 263 +/- 32 (mean +/- SEM), respectively, in the CR group (p > 0.05 for all comparisons). Plasma ACTH and cortisol concentrations were not significantly suppressed in either group after 0.25 mg dexamethasone, but were equally suppressed in both groups to undetectable levels by 1 mg dexamethasone. We conclude that CR asthma is not reflected in an altered secretory rate of endogenous cortisol or in an altered sensitivity of the HPA axis to dexamethasone suppression.
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Am. J. Respir. Crit. Care Med. · Feb 1996
Comparative StudyExogenous surfactants in a piglet model of acute respiratory distress syndrome.
Evidence for surfactant dysfunction in acute respiratory distress syndrome (ARDS) suggests a role for exogenous surfactant which contains apoprotein for resistance to protein inhibition. We compared the effects of KL-4-Surfactant, an artificial preparation containing a synthetic 21 amino acid peptide with SP-B-like activity, with Exosurf, an artificial protein-free surfactant, and Survanta, a bovine protein-containing surfactant, in a saline lung lavage model of ARDS in neonatal piglets. Two sequential series of lung lavages were performed to lower PaO2 < 100 mm Hg, each followed by administration of surfactant or air and a 90-min observation period. ⋯ Only KL-4-Surfactant demonstrated greater pressure-volume characteristics and lower bronchoalveolar protein than those of Controls. We conclude that the physiologic effects of KL-4-Surfactant are more like Survanta in this model. We speculate that KL-4-Surfactant may improve pulmonary function, reduce alveolar protein leak, and thus be efficacious in the treatment of ARDS.
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Am. J. Respir. Crit. Care Med. · Feb 1996
Bedside prediction of mortality from bacteremic sepsis. A dynamic analysis of ICU patients.
The prognosis in patients with sepsis depends on severity of acute illness, underlying chronic diseases, and complications associated with infection. Adjusting for these factors is essential for evaluation of new therapies. The purpose of the present study was to determine variables readily identifiable at the bedside that predict mortality in intensive care unit (ICU) patients with sepsis and positive blood cultures. ⋯ The best two independent prognostic factors were the APACHE II score at the onset of sepsis (OR, 1.13 per unit; CI95, 1.08 to 1.17; p = 0.0016) and the number of organ dysfunctions developing thereafter (OR, 2.39; CI95, 2.02 to 2.82; p < 0.001). In ICU patients with sepsis and positive blood cultures, outcome can be predicted by the severity of illness at onset of sepsis and the number of vital organ dysfunctions developing subsequently. These variables are easily assessed at the bedside and should be included in the evaluation of new therapeutic strategies.
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Am. J. Respir. Crit. Care Med. · Feb 1996
Early detection of lung involvement in lysinuric protein intolerance: role of high-resolution computed tomography and radioisotopic methods.
Pulmonary disease of unknown etiology is a potentially fatal complication in patients with lysinuric protein intolerance (LPI), an autosomal recessive disorder caused by the defective transport of cationic amino acids. Lung involvement was investigated in nine Italian LPI patients through pulmonary function tests and lung imaging studies consisting of conventional chest radiography, high-resolution computed tomography (HRCT), and perfusion and ventilation scintigraphy. One 10-yr-old patient died of severe respiratory insufficiency from alveolar proteinosis. ⋯ Radioisotope studies showed an uneven distribution of perfusion and ventilation, and confirmed the presence of segmental and/or diffuse pulmonary functional defects. No abnormalities of pulmonary function were evident, and answers to a questionnaire excluded primary coexisting lung disease. In patients with LPI, including those without clinical and functional impairment, HRCT and radioisotopic studies appear to be the most sensitive methods for the early diagnosis of lung disease and correct assessment of its progression.