Quantifying pH-induced changes in plasma strong ion difference during experimental acidosis: clinical implications for base excess interpretation
Lorenzo Giosa, Francesco Zadek, Mattia Busana, Giovanna De Simone, Serena Brusatori, Martin Krbec, František Duška, Paolo Brambilla, Alberto Zanella, Alessandra di Masi, Pietro Caironi, Emanuele Perez, Luciano Gattinoni, Thomas Länger
Abstract
This paper challenges the assumed equivalence between changes in plasma strong ion difference (SID) and whole blood base excess (BE) during in vitro acidosis. We highlight that redistribution of strong ions, in the form of albumin ionic-binding and transerythrocyte shifts, alters SID without affecting BE. We demonstrate that these expected SID alterations are predictable from albumin and hemoglobin's charges, or from the noncarbonic whole blood buffer value, allowing a better interpretation of SID and BE during in vitro acidosis.