DSI Buxco FinePointe - Frc; Quasistatic Pressure Volume

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Pulmonary Function Test • Publication 014181-001 Rev 02 • www.datasci.com ©2023 Data Sciences International
FRC
The FRC tests measures the FRC lung volume by using Boyle’s Law. FRC lung volume is the Functional Residual
Capacity. This is the volume of air that remains in the lung at the end of a normal expiration. This lung volume is
important because by knowing this lung volume, it is easy to know all the other lung volumes.
The FRC test produces the following parameters:
Parameter
Description
Units
FRC
Functional Residual Capacity.
mL
R2
Goodness of Fit. A value between 0 and 1 indicating how well the
data fits the assumed model.
DeadSpace
The amount of volume that is in the hardware. Subtracted from the
volume result of Boyles Law to arrive at the FRC value.
mL
DPmax
The maximum pressure change of all the efforts.
cmH
2
O
DVmax
The maximum volume change of all the efforts.
mL
Tocclude
The time the subject was occluded
s
Quasistatic Pressure Volume
The PV test provides information about the static lung properties. Static lung properties are described by the
pressure-volume relationship of the lung. The slope of the Volume-Pressure curve is the instantaneous compliance
at a given pressure.
The PV test produces the following parameters:
Parame
Description
Units
Cchord
Chord Compliance, between 0-10 cm H
2
0
mL/cmH
2
O
Cfvc50
Compliance at 50% VC
mL/cmH
2
O
IC
Inspiratory Capacity. Volume measured from the start of the test to TLC.
mL
VC
Vital Capacity. Volume measured from TLC to the end of the test.
mL
ERV
Expiratory Reserve Volume. The difference between VC and IC.
mL
Pfrc
Pressure at Return to FRC during expiration
cmH
2
O
Cpk
Peak Compliance
mL/cmH
2
O
Ppk
Pressure at Max Compliance
cmH
2
O
Vpk
Volume at Max Compliance
mL
Cp0
Compliance at Zero Pressure
mL/cmH
2
O
Te
Duration of expiration
S