Abstract:
:To be most effective, noninvasive ventilation (NIV) ventilators should synchronize well with patients' breathing. However, the speed with which different ventilators can respond to the transitions between inspiration and expiration may vary, and abnormal respiratory mechanics and mask leaks may exacerbate this problem. This study explored synchronization using a new test lung model designed to simulate acute exacerbations of chronic obstructive pulmonary disease (COPD). Thirteen ventilators were tested against different combinations of tidal volume (VT), airways resistance (Raw), FRC, and mask leak. These combinations ranged from those of a severe exacerbation of COPD, to a mild condition reflecting the optimal triggering conditions a ventilator is likely to encounter. The triggering delays from the beginning and end of "inspiration" of the test lung, to the appropriate responses from the ventilators were measured. Three of the ventilators had trigger delays less than approximately 120 ms at both the beginning and end of expiration under all conditions. Trigger delays of other ventilators were mainly in the range of 120 to 300 ms, although exceptionally as long as 500 ms. Varying the conditions had a variable but generally small effect on triggering times, suggesting that there is a largely unavoidable element to the triggering delays intrinsic to the design of the ventilators.
journal_name
Am J Respir Crit Care Medauthors
Stell IM,Paul G,Lee KC,Ponte J,Moxham Jdoi
10.1164/ajrccm.164.11.2011147keywords:
subject
Has Abstractpub_date
2001-12-01 00:00:00pages
2092-7issue
11eissn
1073-449Xissn
1535-4970journal_volume
164pub_type
杂志文章abstract:INTRODUCTION:Proteinases with a disintegrin and a metalloproteinase domain (ADAMs) have not been well studied in COPD. We investigated whether ADAM9 is linked to COPD in humans and mice. METHODS:ADAM9 blood and lung levels were measured in COPD patients versus controls, and air- versus cigarette smoke (CS)-exposed wil...
journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章
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journal_title:American journal of respiratory and critical care medicine
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doi:10.1164/rccm.201203-0480OC
更新日期:2012-09-01 00:00:00
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journal_title:American journal of respiratory and critical care medicine
pub_type: 临床试验,杂志文章,随机对照试验
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更新日期:2004-10-01 00:00:00
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journal_title:American journal of respiratory and critical care medicine
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更新日期:2001-11-15 00:00:00
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journal_title:American journal of respiratory and critical care medicine
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更新日期:2004-03-01 00:00:00
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journal_title:American journal of respiratory and critical care medicine
pub_type: 临床试验,杂志文章
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journal_title:American journal of respiratory and critical care medicine
pub_type: 临床试验,杂志文章,随机对照试验
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更新日期:2011-04-01 00:00:00
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更新日期:2010-03-01 00:00:00
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更新日期:2012-06-01 00:00:00
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abstract::Kaposi's sarcoma (KS) is the most common neoplasm in persons infected with the human immunodeficiency virus (HIV). However, information about the presenting features of pulmonary KS is limited. To describe the clinical, laboratory, and radiographic features of pulmonary KS, medical records and chest radiographs of 168...
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更新日期:1996-04-01 00:00:00
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更新日期:2000-08-01 00:00:00
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pub_type: 杂志文章,多中心研究
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更新日期:2007-09-01 00:00:00