capacity
[kah-pas´ĭ-te] the power to hold, retain, or contain, or the ability to absorb; usually expressed numerically as the measure of such ability.
closing capacity (CC) the volume of gas in the lungs at the time of airway closure, the sum of the closing volume and the
residual volume. See also
closing volume.
decreased intracranial adaptive capacity a
nursing diagnosis accepted by the North American Nursing Diagnosis Association, defined as the state in which intracranial fluid dynamic mechanisms that normally compensate for increases in intracranial volumes are compromised, resulting in repeated disproportionate increases in
intracranial pressure in response to a variety of noxious and nonnoxious stimuli.
forced vital capacity the maximal volume of gas that can be exhaled from full inhalation by exhaling as forcefully and rapidly as possible. See also
pulmonary function tests.
functional residual capacity the amount of gas remaining at the end of normal quiet respiration.
heat capacity the amount of heat required to raise the temperature of a specific quantity of a substance by one degree Celsius.
inspiratory capacity the volume of gas that can be taken into the lungs in a full inhalation, starting from the resting inspiratory position; equal to the tidal volume plus the inspiratory reserve volume.
total lung capacity the amount of gas contained in the lung at the end of a maximal inhalation.

Subdivisions of total lung capacity: TLC, total lung capacity; V, tidal volume; IC, inspiratory capacity; FRC, functional residual capacity; ERV, expiratory reserve volume; VC, vital capacity; RV, residual volume. From Dorland's, 2000.
virus neutralizing capacity the ability of a serum to inhibit the infectivity of a virus.
vital
[vi´tal] pertaining to life; necessary to life.
vital capacity (VC) the greatest volume of gas that, following maximum inhalation, can be expelled during a complete, slow, forced exhalation; equal to
inspiratory capacity plus
expiratory reserve volume.
Forced vital capacity (FVC) is the greatest volume of air that can be expelled when a person performs a rapid, forced exhalation, which usually takes about five seconds. The greatest volume of air a person can exhale during one, two, three, or more seconds of forced exhalation is called the
forced expiratory volume (FEV). A subscript is added to the abbreviation FEV to indicate the phase during which the particular amount or volume of air is exhaled. A volume exhaled during the first second is designated FEV
1.0, a volume exhaled during the first two seconds is designated FEV
2.0, and so on. The rate at which a specified volume of air is exhaled during a forced exhalation is called
forced expiratory flow (FEF). The rate at which air is exhaled from a forced expiratory volume of 200 mL to one of 1200 mL is designated FEF
200–1200 (formerly called maximal expiratory flow, MEF); the rate from 25 to 75 per cent of the forced vital capacity is designated FEF
25–75% (formerly called maximal midexpiratory flow, MMF).
Laboratory values for vital capacity, forced vital capacity, forced expiratory volume, and forced expiratory flow are usually reported both as absolute values and as statistically derived predicted values based on the age, sex, and height of a patient. The statistical value is reported as a percentage. See also
pulmonary function tests.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.