American journal of respiratory and critical care medicine
-
Am. J. Respir. Crit. Care Med. · Jul 1999
Randomized Controlled Trial Clinical TrialLung function and sputum characteristics of patients with severe asthma during an induced exacerbation by double-blind steroid withdrawal.
Some patients with severe asthma are difficult to control and suffer from frequent exacerbations, whereas others remain stable with anti-inflammatory therapy. To investigate mechanisms of exacerbations, we compared 13 patients 20 to 51 yr of age (11 female, two male) with difficult-to-control asthma (two or more exacerbations during the previous year) and 15 patients 20 to 47 yr of age (13 female, two male) with severe but stable asthma (no exacerbations) after matching for sex, age, atopy, lung function, airway responsiveness, and medication. Exacerbations were induced by double-blind, controlled tapering of inhaled corticosteroids (fluticasone propionate) at weekly intervals. ⋯ We conclude that tapering of inhaled corticosteroids induces a rapid, reversible flare-up of eosinophilic airway inflammation. Patients with difficult-to-control asthma may develop exacerbations despite treatment with inhaled corticosteroids, which appear to have an eosinophil-independent mechanism. This implies that assessment of the nature of exacerbations may contribute to improved treatment for these patients.
-
Am. J. Respir. Crit. Care Med. · Jul 1999
Randomized Controlled Trial Clinical TrialNoninvasive ventilation as a systematic extubation and weaning technique in acute-on-chronic respiratory failure: a prospective, randomized controlled study.
Prolonged duration of endotracheal mechanical ventilation (ETMV) is associated with an increased morbidity and mortality in intensive care unit (ICU) patients. The aim of this study was to assess the usefulness of noninvasive ventilation (NIV) as a systematic extubation and weaning technique to reduce the duration of ETMV in acute-on-chronic respiratory failure (ACRF). Among 53 consecutively intubated patients admitted for ACRF, we conducted a prospective, randomized controlled trial of weaning in 33 patients who failed a 2-h T-piece weaning trial (2 h-WT) although they met simple criteria for weaning. ⋯ The durations of ICU and hospital stays and the 3-mo survival were similar in the two groups. In conclusion, NIV permits earlier removal of the endotracheal tube than with conventional IPSV, and reduces the duration of daily ventilatory support without increasing the risk of weaning failures. NIV should be considered as a new and useful systematic approach to weaning in patients with ACRF who are difficult to wean.