ATS Pulmonary Function Laboratory Manual

chapter  9

Appendix 9.3  Calculations Raw:

Raw = slope of closed − shutter panting slope of open − shutter panting

− Rapp

or

Raw = Δ Pao/ Δ Pbox Δ ˙ V/ Δ Pbox

− R app

Where:   R app by the manufacturer) TGV:

= Correction factor for the resistance of the apparatus (determined by the laboratory or supplied

TGV = PB × × Pbox calibration factor Pao calibration factor Where:   PB = Barometric pressure minus water vapor pressure at 37° C (in cm H 2 O) Note: 1.36 converts mmHg to cm H 2 O slope =Δ Pao/ Δ Pbox ������� ������a��� � �Raw = Raw × TGV ��e���� �������a��e�Gaw = Gaw/TGV , where Gaw = 1 Raw 1 closed − shutter panting

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