Abstract:
:Used adjunctively during mechanical ventilation, tracheal gas insufflation (TGI) improves CO2 elimination, principally by decreasing effective anatomic dead space. Continuing lung deflation at end- expiration raises the end-expiratory C02 concentration within the proximal airway, and could theoretically reduce the efficiency of a given catheter flow. To test this possibility, we designed a series of experiments that examined the influence of TGI delivery patterns on the efficiency of CO2 elimination. Using a gating device, catheter flow was delivered selectively during desired portions of expiration. Paralyzed, ventilated dogs were studied at short and extended inspiratory time fractions (TI/TT) with inspiratory tidal volume and ventilator frequency held constant. The expiratory flush volume, not the pattern of gas delivery, determined the observed decline in PaCO2, provided that the end-expiratory period was included in the catheter flush period. Despite continuing end-expiratory lung deflation (extended TI/TT), catheter effectiveness remained the same at matched expiratory flush volumes. To determine if enhanced distal mixing at the higher catheter flows required during the extended TI/TT (to match expiratory flush volume) masked a decrease in efficiency, we repeated the experiment with a tip-inverted catheter. We again found that matched catheter delivered expiratory volumes were similarly effective. With or without ongoing lung deflation, the volume of gas flushed during the expiratory period determined the effectiveness of TGI, provided that inspired minute ventilation remains unchanged and end-expiration is included in the catheter flush period.
journal_name
Am J Respir Crit Care Medauthors
Ravenscraft SA,Shapiro RS,Nahum A,Burke WC,Adams AB,Nakos G,Marini JJdoi
10.1164/ajrccm.153.6.8665040subject
Has Abstractpub_date
1996-06-01 00:00:00pages
1817-24issue
6 Pt 1eissn
1073-449Xissn
1535-4970journal_volume
153pub_type
杂志文章abstract::Patients in whom acid-fast bacilli smear-positive pulmonary tuberculosis was newly diagnosed were randomized to receive 400 mg moxifloxacin, 300 mg isonaizid, or 600 mg rifampin daily for 5 days. Sixteen-hour overnight sputa collections were made for the 2 days before and for 5 days of monotherapy. Bactericidal activi...
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
doi:10.1164/rccm.200305-682OC
更新日期:2003-12-01 00:00:00
abstract:RATIONALE:The impact of asthma on chronic lung function deficits is well known. However, there has been little study of ethnic differences in these asthma-associated deficits. OBJECTIVES:To examine whether there are ethnic differences in the effects of asthma on children's lung function. METHODS:We evaluated the impa...
journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章
doi:10.1164/rccm.200912-1863OC
更新日期:2011-03-01 00:00:00
abstract::Most data about the course of occupational asthma after removal from exposure are based upon the longitudinal assessment of employees exposed to substances inducing late asthmatic reactions in bronchial provocation tests. It was the aim of this study to describe the course of immediate-type occupational asthma after a...
journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章
doi:10.1164/ajrccm.150.4.7921450
更新日期:1994-10-01 00:00:00
abstract::Theophylline is well-established in the management of asthma, and there is some evidence of an antiinflammatory effect in asthma. It is not known whether theophylline affects inflammatory markers such as sputum eosinophils and exhaled nitric oxide (NO) in patients with mild asthma not receiving inhaled steroid therapy...
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
doi:10.1164/ajrccm.164.2.2006043
更新日期:2001-07-15 00:00:00
abstract::Normoxic lung ischemia/reperfusion (I/R) leads to oxidative injury of the pulmonary tissue. We analyzed angiotensin-converting enzyme (ACE) in perfused rat lungs upon I/R in order to assess the endothelial injury produced. I/R led to a time-dependent increase in ACE activity in the perfusate, from 145+/-14 mU to 252+/...
journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章
doi:10.1164/ajrccm.156.4.96-12116
更新日期:1997-10-01 00:00:00
abstract::The forced oscillation technique (FOT) and interrupter technique are particularly attractive for pediatric use as they require only passive cooperation from the patient. We compared the sensitivity and specificity of these methods for detecting airway obstruction and its reversibility in 118 children (3-16 yr) with as...
journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章
doi:10.1164/ajrccm.164.6.2010153
更新日期:2001-09-15 00:00:00
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journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章
doi:10.1164/rccm.201203-0398OC
更新日期:2012-11-01 00:00:00
abstract:RATIONALE:Regional hypoventilation in bronchoconstricted patients with asthma is spatially associated with reduced perfusion, which is proposed to result from hypoxic pulmonary vasoconstriction (HPV). OBJECTIVES:To determine the role of HPV in the regional perfusion redistribution in bronchoconstricted patients with a...
journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章
doi:10.1164/rccm.201612-2438OC
更新日期:2017-10-01 00:00:00
abstract::Despite several codes of research ethics, the issuance of comprehensive rules regarding informed consent by governmental agencies, and numerous writings on the subject of informed consent, many commentators still question the quality of the informed consent process in clinical research. A major concern is that investi...
journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章,评审
doi:10.1164/ajrccm.154.3.8810590
更新日期:1996-09-01 00:00:00
abstract::In order to assess the usefulness of sputum analysis in studying plasma-protein exudation and local secretion of proteins in the airways, we measured specific proteins in the sputum sol phase (SSP) and sputum gel phase (SGP) from patients with stable asthma or chronic obstructive pulmonary disease (COPD). Protein leve...
journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章
doi:10.1164/ajrccm.150.6.7952610
更新日期:1994-12-01 00:00:00
abstract::An imbalance of proinflammatory cytokines such as TNF-alpha, IL-1 beta, and the neutrophil chemotactic factor IL-8 and inhibitors (e.g., soluble TNF receptors and IL-1ra) in the lung during the first week of life may contribute to prolonged pulmonary inflammation and fibrosis in bronchopulmonary dysplasia (BPD). Disod...
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
doi:10.1164/ajrccm.156.5.9611088
更新日期:1997-11-01 00:00:00
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journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章
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更新日期:2005-03-01 00:00:00
abstract:RATIONALE:Defining the biogeography of bacterial populations in human body habitats is a high priority for understanding microbial-host relationships in health and disease. The healthy lung was traditionally considered sterile, but this notion has been challenged by emerging molecular approaches that enable comprehensi...
journal_title:American journal of respiratory and critical care medicine
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更新日期:2011-10-15 00:00:00
abstract:RATIONALE:Diesel motor exhaust is classified by the International Agency for Research on Cancer as probably carcinogenic to humans. The epidemiologic evidence is evaluated as limited because most studies lack adequate control for potential confounders and only a few studies have reported on exposure-response relationsh...
journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章,多中心研究
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更新日期:2011-04-01 00:00:00
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journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章
doi:10.1164/ajrccm.150.1.8025780
更新日期:1994-07-01 00:00:00
abstract:RATIONALE:In the absence of active tuberculosis, a positive tuberculin skin test (TST) or interferon-γ release assay (IGRA) result defines latent infection with Mycobacterium tuberculosis, although test results may vary depending on immunodeficiency. OBJECTIVES:This study compared the performance of TST and IGRAs in f...
journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章
doi:10.1164/rccm.201405-0967OC
更新日期:2014-11-15 00:00:00
abstract::Silicosis is characterized by fibrosing nodular lesions that may eventually develop into progressive massive fibrosis (PMF). Cytokines (interleukin-1beta [IL-1beta], tumor necrosis factor-alpha [TNF-alpha] and growth factors insulin-like growth factor-1 [IGF-1] platelet-derived growth factor [PDGF]) have been implicat...
journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章
doi:10.1164/ajrccm.154.4.8887610
更新日期:1996-10-01 00:00:00
abstract::In unilateral lung injury, application of global positive end-expiratory pressure (PEEP) may cause overdistension of normal alveoli and redistribution of blood flow to diseased lung areas, thereby worsening oxygenation. We hypothesized that selective application of tracheal gas insufflation (TGI) will recruit the inju...
journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章
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更新日期:2001-08-15 00:00:00
abstract:RATIONALE:Patients of Hispanic origin with cystic fibrosis (CF) are the largest growing minority, representing 8.5% of patients with CF in the United States. No national survival analysis of this group has ever been undertaken. OBJECTIVES:We aimed to determine whether Hispanic ethnicity within the CF population is ass...
journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章
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更新日期:2018-10-15 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:2020-05-15 00:00:00
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journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章
doi:10.1164/rccm.201311-1951OC
更新日期:2014-04-01 00:00:00
abstract:RATIONALE:Immediate graft performance after lung transplantation is associated with short- and long-term clinical outcomes. However, the biologic mechanism that determines outcomes is not fully understood. OBJECTIVES:To investigate the impact of cell death signals at 24 and 48 hours after lung transplantation on short...
journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章
doi:10.1164/rccm.201510-2115OC
更新日期:2016-07-01 00:00:00
abstract:RATIONALE:Patients with severe asthma (SA) are less responsive to the beneficial effects of corticosteroid (CS) therapy, and relative CS insensitivity has been shown in airway smooth muscle cells (ASMC) from patients with SA. OBJECTIVES:We investigated whether there was a defect in the actions of the glucocorticoid re...
journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章
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更新日期:2015-01-01 00:00:00
abstract::Eotaxin, a selective chemoattractant for eosinophils, induces lung eosinophilia and bronchial hyperresponsiveness (BHR) when administered intratracheally to interleukin-5 (IL-5) transgenic mice. We determined whether these effects of eotaxin were mediated through the production of cysteinyl-leukotrienes. IL-5 transgen...
journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章
doi:10.1164/ajrccm.160.2.9810101
更新日期:1999-08-01 00:00:00
abstract:RATIONALE:The sympathetic nervous system has been reported to be activated in pulmonary arterial hypertension (PAH). OBJECTIVES:We investigated the prognostic significance of muscle sympathetic nervous system activity (MSNA) in PAH. METHODS:Thirty-two patients with PAH were included in the study and underwent a measu...
journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章
doi:10.1164/rccm.200912-1856OC
更新日期:2010-06-01 00:00:00
abstract:RATIONALE:Allergic bronchopulmonary aspergillosis (ABPA) is characterized by a Th2 immune response. Mouse models suggest a critical role for the Th2 chemokines thymus- and activation-regulated chemokine (TARC) and macrophage-derived chemokine (MDC) in ABPA. OBJECTIVES:To determine whether serum levels of TARC and MDC ...
journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章
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更新日期:2006-06-15 00:00:00
abstract:RATIONALE:When subclavian access is not possible, controversy exists between the internal jugular and femoral sites for the choice of central-venous access in intensive care unit patients. OBJECTIVES:To compare infection and colonization rates of short-term jugular and femoral catheters. METHODS:Using data from two m...
journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章,多中心研究,随机对照试验
doi:10.1164/rccm.201303-0460OC
更新日期:2013-11-15 00:00:00
abstract:RATIONALE:Controlled mechanical ventilation (CMV) results in atrophy of the human diaphragm. The autophagy-lysosome pathway (ALP) contributes to skeletal muscle proteolysis, but its contribution to diaphragmatic protein degradation in mechanically ventilated patients is unknown. OBJECTIVES:To evaluate the autophagy pa...
journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章
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更新日期:2010-12-01 00:00:00
abstract::It is controversial whether mutations in cystic fibrosis transmembrane conductance regulator intrinsically dysregulate inflammation. We characterized passage 2 human tracheobronchial epithelial cell cultures morphologically and physiologically and determined whether cytokine production or nuclear factor-kappaB activat...
journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章
doi:10.1164/rccm.200207-765OC
更新日期:2004-03-01 00:00:00
abstract::Ventilation style influences lung injury and the amount of large-aggregate biophysically active surfactant in adult lungs. We asked how positive end-expiratory pressures (PEEP) would influence clinical responses and surfactant pools in surfactant-treated preterm lambs ventilated for 7 h with tidal volumes (VT) of 10 m...
journal_title:American journal of respiratory and critical care medicine
pub_type: 杂志文章
doi:10.1164/ajrccm.160.2.9902016
更新日期:1999-08-01 00:00:00