Variation of Carbonic Acid pK’19in Blood and Urine during NaHCO3 Infusion and NH4CI Loading: A Study of Two Renal Acidotic Patients

• Main Authors: Gerard J. Van Stekelenburg, Cees Valk, Raymond A. M. G. Donckerwolcke
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: Carbonic acid
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.631.7623; http://www.clinchem.org/content/26/1/60.full.pdf

Iog(HCO/S#{149}pc02), the millirnolar partition coefficient, per mmHg pressure (S), and pK1 are considered to be con-stants.Combining these two constants gives pH = pK19 + log(HCO/po2). In this paper, we report the results of a study designed to test the constancy of pK19. This was done by varying the blood and urine pH in two patients by administration of NaHCO3 and NH4CI. The Pco2 pH, and total CO2 were determined independently, and the values obtained were substituted in the equation, solving for pK19. The pK19 was variable in the blood and urine of both pa-tients. In a 16-month-old child, suffering from a transient type of renal acidosis, a linear relationship between pH and pK19 was noted. In blood, the relationship was pK19 = 10.25- 0.352 pH, and for urine, pKig = 9.46- 0.248 pH. When this patient was restudied six months later, the re-