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Removing the pH From Physician Phrases

Richard E. Neiberger, MD, PhD
JAMA. 1991;266(18):2559. doi:10.1001/jama.1991.03470180059021.
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To the Editor.  —I was helping a group of medical students work through a complex acid-base problem last week. I recognized again how difficult it is for a novice to understand a complex physiological abnormality when the perturbed variable (H+ concentration) is expressed as the log of the reciprocal of the concentration: pH = log(1/[H+]), or the negative log of the concentration.In the days of Arrhenius, Severing-haus, and Henderson-Hasselbalch, concentrations expressed in nanomoles presented some difficulty for calculations. This is no longer true. In the 1990s, it is just as easy to consider hydrogen-ion concentration as 20, 40, or 60 nmol/L as it is to consider potassium as 3, 4, or 5 mmol/L.Using pH once served a useful purpose, like the horse and buggy, logarithms, and the slide rule. In the 1990s, pH no longer serves a useful purpose in clinical medicine. The concept of pH only adds confusion


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