NDD easyone pro, Operator'S Manual, Page: 147 / 188

EasyOne Pro™ / EasyOne Pro™ LAB 147
Appendix
Adjustment for P
AO2
or Altitude
The following formula for DL
adj
is applied if the patient uses supplemental
O
2
:
DL
adj
= DLCO × (1 + 0.0035 × (P
AO2
– 100)) P
AO2
in mm Hg
If no supplemental O2 is applied the following formula is always applied to
correct for altitude. The partial pressure of O2 in the lungs is computed by
subtracting the water vapor pressure in the lungs (47 mmHg) from the ambi-
ent pressure and multiplying it with the O2 concentration:
DL
adj
= DLCO × (1 + 0.0031 × (P
IO2
– 150)) P
IO2
in mmHg
P
IO2
= (P
amb
– 47) × 0.20942 P
amb
and P
H2O
in mm Hg
Unit conversion: P [mm Hg] = P [mbar] × 0.750
Pressure at altitude:
P
amb
in mm Hg, h in m
Allowed range for P: 100 to 750 mm Hg
Adjustment for COHb concentration and CO back pressure
Adjustment for carboxyhaemoglobin is performed as follows:
DL
adj
= DLCO / (102 % - CO-Hb%) CO-Hb in %
Allowed range for CO-Hb: 0 bis 100 %
Default value: 2 % (at this value DL
adj
equals DCLO)
Example of DLCO adjustment
The following example can be used to test the DLCO adjustment feature.
Pamb 760 1
0 0065 h

,
288
--------------------------------
–
 
 
5 255 ,

=
Factor Adjustment for
men
Adjustment for
women and children
(< 15 J)
Hemoglobin 32.4675 mmol/l 0.7023 0.69292
P
A02
400 mbar 1.7 1.7
CO-Hb 30 % 1.38889 1.38889
Total correction factor 1.6582 1.6361