American journal of respiratory and critical care medicine
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Am. J. Respir. Crit. Care Med. · Nov 2003
Decision analysis of antibiotic and diagnostic strategies in ventilator-associated pneumonia.
The optimal strategy for ventilator-associated pneumonia remains controversial. To clarify the tradeoffs involved, we performed a decision analysis. Strategies evaluated included antibiotic therapy with and without diagnostic testing. ⋯ Testing with mini-BAL did not improve survival but did decrease costs (US dollars 41483 vs. US dollars 39967) and antibiotic use (63 vs. 39 antibiotic days per survivor). From the perspective of minimizing cost, minimizing antibiotic use, and maximizing survival, the best strategy was three antibiotics with mini-BAL.
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Am. J. Respir. Crit. Care Med. · Nov 2003
End-tidal carbon monoxide corrected for lung volume is elevated in patients with cystic fibrosis.
Several factors influence levels of end-tidal carbon monoxide (ETCO). We studied determinants of ETCO corrected for inhaled CO (ETCOc) levels in healthy control subjects and compared ETCOc levels and determinants between healthy control subjects and patients with cystic fibrosis (CF). Thirty healthy control subjects (mean +/- SD age, 23 +/- 6 years) and twenty clinically stable patients with CF, aged 13.5 +/- 3.5 years were included. ⋯ Patients with CF showed no difference in ETCOc levels compared with control subjects (mean 1.2 +/- 0.4 ppm vs. 1.3 +/- 0.4 ppm, p = 0.32), but patients with CF had lower total lung capacity-helium than healthy control subjects. ETCOc corrected for lung volume was significantly higher in patients with CF compared with control subjects (p < 0.001). We hypothesize that a possible increase in breath CO caused by airway inflammation might be masked by differences in lung volumes between control subjects and patients with CF.
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Am. J. Respir. Crit. Care Med. · Nov 2003
Cigarette smoke produces airway wall remodeling in rat tracheal explants.
Small airway remodeling ("small airways disease") is a common finding in cigarette smokers and is an important cause of airflow obstruction. Airway remodeling is usually attributed to the effects of cigarette smoke-induced inflammation in the airway wall, but little is actually known about its pathogenesis. We exposed rat tracheal explants to cigarette smoke and then maintained them in air organ culture. ⋯ AG1478, an inhibitor of epidermal growth factor receptor signaling, also prevented increased procollagen gene expression, but PD98059 and SB203580, inhibitors of mitogen-activated protein kinases, did not. These findings indicate that cigarette smoke can directly induce airway remodeling, specifically airway wall fibrosis, probably through active oxygen species-dependent transactivation of the epidermal growth factor receptor and subsequent nuclear factor-kappaB activation. Smoke-evoked inflammatory cells are not required for this process.