OPTIMedical OPTI CCA-TS - Page 252

Operator’s Manual – OPTI CCA-TS A-13
APPENDIX A - TECHNICAL SPECIFICATIONS
AaDO
2
t
Alveolar to arterial oxygen tension difference corrected to patient temperature other than 37 ºC.
AaDO AO aO
t t t
2 2 2
= −P P
[mmHg]
7
where:
PAO
2
t
= (P
total
– PH
2
O
t
) FIO
2
– PACO
2
t
[FIO
2
+ (1 – FIO
2
)/R]
with PH
2
O
t
= 47 * 10
[0.0237 – 0.0001 (t-37)] (t-37)
and PACO
2
= PaCO
2
(alveolar PCO
2
= arterial PCO
2
)
Apply above equation for PAO
2
t
≥ PO
2
t
,
otherwise PAO
2
t
= PO
2
t
Hct(c)
Hct(c) as a function of tHb.
[ ]
Hct(c) tHb g / dl MCHC% / 100)= / (
[%]
10
Where MCHC% is the Mean Cell Hemoglobin Concentration, representing the average
concentration by weight of hemoglobin inside the average red cell.
Default value of MCHC% = 33.3% (input range: 29.0% to 37.0%)
AG
The anion gap is a calculated parameter used to express the difference in concentrations of major
cations and anions in the blood specimen.
AG = Na
+
+ K
+
- Cl
-
- HCO3
-
[mmol/L]
nCa
++
The ionized calcium value normalized to pH = 7.40.
For blood:
nCa
++
(pH = 7.4) = Ca
++
* 10
0.22*(pH-7.4)
[mmol/L]
For plasma or serum:
nCa
++
(pH = 7.4) = Ca
++
* 10
0.24*(pH-7.4)
[mmol/L]
10
Simmons A, ed. Hematology, “A Combined Theoretical & Technical Approach”, pp. 28-29 (Philadelphia, W.B.
Saunders, 1989)