Lung vital capacity

Vital capacity (VC) The volume of air that can be taken in and pushed out of the lungs. 

A suspected diagnosis of COPD should be based on the patient s symptoms and/or history of exposure to risk factors. Spirometry is required to confirm the diagnosis. The presence of a postbronchodilator FEV,/FVC ratio less than 70% [the ratio of FEV, to forced vital capacity (FVC)] confirms the presence of airflow limitation that is not fully reversible.1,2 Spirometry results can further be used to classify COPD severity (Table 12-1). Full pulmonary function tests (PFTs) with lung volumes and diffusion capacity and arterial blood gases are not necessary to establish the diagnosis or severity of COPD. 

Isoproterenol (104) is an important agent for classification because of its selective p-receptor agonist activity. It is of special interest that its chronotropic (increase in heart rate) and inotropic (increase in force of contraction) effects exceed that of epinephrine it is also used in the management of mild to moderate asthma due to its bronchodilating effect, resulting in increased vital capacity of the lungs. 

Define functional residual capacity, inspiratory capacity, total lung capacity, and vital capacity... 

Chronic theophylline use in COPD has been shown to produce improvements in lung function, including vital capacity and FEVj. Subjectively, theophylline has been shown to reduce dyspnea, increase exercise tolerance, and improve respiratory drive. Nonpulmonary effects that may contribute to better functional capacity include improved cardiac function and decreased pulmonary artery pressure. 

As regards respiratory apparatus, intoxication is manifested in the development of catarrh of upper air passages and bronchitis with dyspnea, but more often damage is limited to impaired vital capacity of lungs. Affection of gastrointestinal tract is manifested in gastritis and chronic colitis. 

Albuterol is a )32-adrenergic sympathomimetic amine with pharmacological similarities to terbutaline. It has almost no effect on jSj-adrenoreceptors of the heart. It has expressed broncholytic effects— prevention or relief of bronchi spasms, lowering respiratory tract resistance, and increasing the vital capacity of the lungs. 

Following inhalation exposure of humans to nickel particles, primarily as nickel oxides and nickel refinery dust, the respiratory system is the primary target. Effects noted included chronic bronchitis, emphysema, reduced vital capacity, and cancers of the lungs and nasal sinus. These effects occurred at... 

Lung function. Exposure of six men to barley dust for 2 days decreased ventilatory capacity. Five volunteers not previously exposed to barley dust, when exposed to the dust for 2 hours, decreased the ventilatory capacity ranging from 200 mL to 800 mL, with recovery taking up to 72 hours. All of the subjects had decreases in flow at 50% vital capacity hut little or no change in flow at 75% vital capacity. In three subjects, there was a drop in specific conductance... 

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