Maquet SERVO-air, Руководство пользователя

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6.11.2 Static measurements
The inspiratory and expiratory hold can be
used to perform certain measurements:
• PEEP
tot
: set PEEP + intrinsic PEEP
• C
static
: static compliance, a measure of the
elastic properties of the respiratory system.
A decrease in compliance implies stiffer
lungs.
• E: elastance, has different compliances and
resistances in the lungs and an increase in
elastance implies stiffer lungs.
• R
i
: inspiratory resistance
• R
e
: expiratory resistance
• Tc: time constant, calculated as C
static
x R
e
.
Some lung units have decreased
compliance, and some have increased
resistance, or both. Differences in R
e
and
C
static
affect the speed at which the lung
units are filled and emptied. An expiration
time of three time constants is
recommended to avoid auto PEEP.
• P
plat
: pressure during end inspiratory pause
Inspiratory hold
This function is activated by pressing
INSPIRATORY HOLD for a maximum of
30 seconds. The inspiratory and expiratory
valves close after inspiration. This function can
provide an exact measurement of the end
inspiratory lung pressure. It can be used to
pause ventilation during X-ray or to determine
the plateau pressure (P
plat
), or, together with
the expiratory hold, to calculate static
compliance.
Expiratory hold
Expiratory and inspiratory valves are closed
after the expiration phase is completed for as
long as EXPIRATORY HOLD is pressed, but
only up to a maximum of 30 seconds.
Expiratory hold provides an exact
measurement of the end expiratory pause
pressure. It can be used to determine total
PEEP and, together with inspiratory hold,
static compliance (C
static
). The dynamic
pressure is displayed on the PEEP numerical
value.
6.11.3 Nebulization
Refer to section Nebulization on page 103.
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SERVO-air Ventilator System v2.2, User's Manual
| 6 | Ventilatory settings and functions |