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PubMed · 237520

A simple method for computing acid-base state.

J P Blackburn·T D Preston·D A Strickland
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Abstract

Simple methods are described for computing the variables derived from the Siggaard-Andersen nomogram, where the in vitro buffer line is either established by direct measurement or calculated from measurements of pH, Pco2 and haemoglobin. Calculations are performed using the equation of the pH-log Pco2 buffer line, the Henderson-Hasselbalch equation, and the polynomials: BE=-38.402+1.8970 (SB)-0.013342 (SB)-2 m-equiv/litre; SL=-69.046+17.377 (pH40)-1.1121 (pH40)-2; SH=-123.30+31.357 (pH40)-2.0143 (pH40)-2. Then haemoglobin=7.5 (1+(S-SL)/(SH-SL)) G/100 ml, where S is the slope of the buffer line. Results are sufficiently accurate for clinical purposes.

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Acid-Base EquilibriumCarbon DioxideHemoglobinsHydrogen-Ion ConcentrationMathematicsModels, BiologicalPartial PressureJournal Article

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J P Blackburn, T D Preston, D A Strickland. 1975. A simple method for computing acid-base state.. https://doi.org/10.1093/bja%2F47.4.500

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