MINIREVIEW
Hyperinflation:
Control of Functional Residual Lung Capacity
F.
PALEČEK
Institute
of Pathophysiology, Second Faculty of Medicine,
Charles University, Prague, Czech Republic
Received
August 8, 2000
Accepted October 17, 2000
Summary
Hyperinflation
is the consequence of a dysbalance of static
forces (determining the relaxation volume) and/or
of the dynamic components. The relaxation volume
is determined by an equilibrium between the
elastic recoil of the lungs and of the chest
walls. The dynamic components include the pattern
of breathing, upper airway resistance and
postinspiratory activity of inspiratory muscles.
The respiratory and laryngeal muscles are under
control and thus both static and dynamic
hyperinflation can be secured. Our knowledge of
the mechanism of increased FRC is based on
clinical observations and on experiments. The
most frequent stimuli leading to a dynamic
increase of functional residual lung capacity
(FRC) include hypoxia and vagus afferentation.
Regulation of FRC is still and undetermined
concept. The controlled increase of FRC,
hyperinflation, participates in a number of lung
diseases.
Key
words
Functional
residual activity · Hyperinflation · Control of
breathing
Reprint
requests
Prof.
F. Paleček, Institute of Pathophysiology, Second
Medical Faculty, Plzeňská 130, 150 00 Prague 5,
Czech Republic, tel., fax: +4202 311 0568,
e-mail: F.Palecek@lf2.cuni.cz
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