Disease relevance of Airway Obstruction

• Theophylline clearance decreased in one patient with worsening airway obstruction, whereas clearance increased in one patient with resolving pneumonia and in one patient with improving congestive heart failure [1].
• Clinical studies of sudden upper airway obstruction in patients with hereditary angioedema due to C1 esterase inhibitor deficiency [2].
• We administered acetazolamide to six patients with symptomatic central sleep apnea, a disorder of respiratory rhythm with little or no upper airway obstruction [3].
• Four definitions of chronic obstructive pulmonary disease (COPD) were used: (1) chronic bronchitis, (2) chronic bronchitis with airway obstruction, (3) shortness of breath, and (4) shortness of breath with airway obstruction [4].
• We examined Pneumocystis colonization rates in lung tissue obtained during lung resection or transplantation in smokers with a range of airway obstruction severity and in a control group with lung diseases other than COPD [5].

Psychiatry related information on Airway Obstruction

• Thirteen children (mean age, 45 months) with nocturnal symptoms of upper airway obstruction, the result of enlarged tonsils, were tested during wakefulness (W) and sleep (S) induced by chloral hydrate (less than or equal to 50 mg/kg) [6].
• A smoking cessation program plus inhaled ipratropium improved survival in smokers with asymptomatic airway obstruction [7].
• When no airway obstruction was detected over a period of 30 min, the pressure was lowered once during the night in steps of 1 mbar at intervals of at least 10 min, until obstructive events reappeared, whereupon the pressure was again increased as described above, until, once more, no signs of airway obstruction and no arousals occurred [8].

High impact information on Airway Obstruction

• The enzyme 5-lipoxygenase catalyzes the metabolism of arachidonic acid to form products that have been implicated in the airway obstruction of asthma [9].
• We conclude that theophylline has a potent and long-lasting effect on diaphragmatic strength and fatigue in patients with fixed airway obstruction [10].
• In contrast to normal individuals, asthmatic individuals respond to adenosine challenge with marked airway obstruction, and concentrations of adenosine are elevated in the bronchoalveolar lavage fluid of asthma patients [11].
• Maximum expiratory flow rate at 30 percent of vital capacity above residual volume served as an index of airway obstruction in comparing the effects of leukotriene C and histamine administered by aerosol to five normal persons [12].
• In addition, although LTD had a rapid onset of effect, similar to that of histamine, the airway obstruction produced by LTD was longer lasting, thereby reflecting more closely the response of asthmatic allergic individuals to antigen inhalation [13].

Chemical compound and disease context of Airway Obstruction

• Several common pulmonary disorders characterized by mucus hypersecretion and airway obstruction may relate to increased levels of inhaled or endogenously generated oxidants (O2 metabolites) in the respiratory tract [14].
• The potent oxidant peroxynitrite may contribute to airway obstruction and hyperresponsiveness and epithelial damage in asthma [15].
• Asthma results from an intrapulmonary allergen-driven Th2 response and is characterized by intermittent airway obstruction, airway hyperreactivity, and airway inflammation [16].
• This study compared the efficacy and side effects of 1.25, 2.5, 5, 10, and 15 mg of albuterol and isoproterenol hydrochloride administered by intermittent positive pressure breathing (IPPB) to 12 patients with reversible airway obstruction [17].
• Methacholine challenge has been proposed as a diagnostic test in situations where clinical asthma is suspected but reversible airway obstruction cannot be demonstrated spirometrically [18].

Biological context of Airway Obstruction

• Finally, we extended this method to show that the linkage of Dpter, atopy, BHR, FEV1, asthma, and airway obstruction to chromosome 20q13 is unlikely to be due to chance and may result from a quantitative trait locus in this region that affects several of these traits [19].
• RESULTS: Montelukast improved airway obstruction (forced expiratory volume in 1 second, morning and evening peak expiratory flow rate) and patient-reported end points (daytime asthma symptoms, "as-needed" beta-agonist use, nocturnal awakenings) (P<.001 compared with placebo) [20].
• We estimated the prevalence of asthma in the study groups on the basis of the criteria of attacks of wheezing, reversible airway obstruction, atopy, and that increased IgE [21].
• Nebulized epinephrine has been advocated as a treatment for airway obstruction in infants with bronchiolitis; however, its effect on respiratory mechanics and gas exchange has been poorly documented to date [22].
• In patients not on steroid treatment ethane was correlated to airway obstruction as assessed by the ratio of residual volume to total lung capacity (RV/ TLC) (r = 0. 66, p < 0.05) and exhaled CO (r = 0.65, p < 0.05) [23].

Anatomical context of Airway Obstruction

• This was confirmed by showing that pretreatment with a monoclonal antibody to ICAM-1 did not inhibit the acute influx of neutrophils associated with late-phase airway obstruction, whereas a monoclonal antibody to ELAM-1 blocked both the influx of neutrophils and the late-phase airway obstruction [24].
• Additional post hoc factor analyses provided similar results when the sample was divided into 2 subgroups by randomization, presence of airway obstruction, degree of BHR, percentage of sputum eosinophils, or concentration of sputum ECP [25].
• Mast cell mediators are also increased in persons with allergies, with the concentrations of histamine, tryptase, and prostaglandin D2 being proportional to the degree of airway obstruction and bronchial hyperresponsiveness [26].
• When only considering patients with COPD, negative correlations were found between carbonyl groups and airway obstruction, and between hydroxynonenal-protein adducts and respiratory muscle strength [27].
• ETS exposure significantly enhanced citric acid-induced cough by 56% and maximal Penh (a measure of airway obstruction) by 43%, effects that were attenuated by the NK-1 receptor antagonist in the nucleus tractus solitarius [28].

Gene context of Airway Obstruction

• TSLP and TARC/CCL17 expression correlated with airway obstruction [29].
• The high level of TNF-alpha in the SSP of COPD-HI patients is in accord with the proposed role of TNF-alpha in the development of airway obstruction in COPD patients [30].
• Expression of CD51 in the distal airways correlated with the degree of airway obstruction (r = -0.57, P = .001) [31].
• We conclude that there is increased inflammation and IL-4 gene expression in the mucus-secreting glands and the airway mucosa of smokers with bronchitis: both are lower in those with CB and coexisting COPD suggesting that airway inflammation in CB is reduced when airway obstruction develops [32].
• Cystic fibrosis (CF) is characterized by progressive airway obstruction [33].

Analytical, diagnostic and therapeutic context of Airway Obstruction

• In a random crossover study, the selective platelet-activating factor antagonist, BN 52021 (60 mg/kg, orally, 1 hour before allergen challenge), significantly reduced the allergen-induced airway obstruction (p less than 0.005) [34].
• A randomized double-blind comparison of aerosolized META, ISO, ATR, and PI solutions delivered by motorized mist nebulizer was conducted in subjects with known reversible airway obstruction [35].
• Pulmonary histopathologic scores, airway obstruction measured by plethysmography, and airway hyperresponsiveness after methacholine challenge were significantly reduced in mice treated with the anti-RSV antibody 24 h before inoculation compared with those for untreated controls [36].
• The sites of airway obstruction and dilatation after terbutaline administration were studied by inhalation imaging and pulmonary function tests in 12 stable asthmatic patients [37].
• Deposition pattern of radiolabeled salbutamol inhaled from a metered-dose inhaler by means of a spacer with mask in young children with airway obstruction [38].

References