OPTIMedical OPTI CCA-TS - Page 248

Operator’s Manual – OPTI CCA-TS A-9
APPENDIX A - TECHNICAL SPECIFICATIONS
HCO
3
-
Bicarbonate concentration in plasma.
HCO CO
3
pH
−
−
= ⋅ ⋅0 0307 10
2
6 105
.
( . )
P
[mmol/L]
1
st.HCO
3
-
Standard bicarbonateoftheblood,denedastheplasmabicarbonateconcentrationinblood
which has been equilibrated at 37 ºC with a gas mixture having a PCO
2
= 40 mmHg.
( )
st.HCO 10
3
st.pH 6.022
−
−
=
[mmol/L]
6
tCO
2
Total concentration of CO
2
in plasma, the sum of dissolved CO
2
and bicarbonate.
tCO HCO (0.0307 CO )
2 3 2
= + ⋅
−
P
[mmol/L]
7
BE
The base excess of the blood results from a calculation to determine the titratable base of the
blood, which in principle is measured by titration of the blood with a strong acid or base to a pH
of 7.4 with PCO
2
= 40 mmHg at 37 ºC.
( )( )
[ ]
−
+−−⋅+⋅⋅⋅−=
3
HCO24.87.4pH7.7tHb43.1tHb)0.014(1BE
[mmol/L]
7
BE
ecf
Thebaseexcessofextracellularuidisaquantitythatreectsonlythenon-respiratory
components of acid-base balance (tHb = 5 g/dL).
( )
−
+−−⋅=
3ecf
HCO8.244.7pH2.16BE
[mmol/L]
7
7
CLSI. Blood Gas and pH Analysis and Related Measurements; Approved Guideline. NCCLS document C46-A,
2001.