The nature of unmeasured anions in critically ill patients

Excerpt

We read with interest the commentary of Venkatesh and Morgan in the February issue of Critical Care [1], in which they discuss the continuing need for clarification of the nature of unmeasured anions in critically ill patients. The questions asked in this commentary arise from the study of Bruegger and colleagues in a previous issue of this journal [2]. The main issue discussed is the ongoing uncertainty about the contribution of intermediates of the tricarboxylic acid (TCA) cycle to the strong ion gap (SIG). As Venkatesh and Morgan accurately point out, the extremely high concentrations of acetate and citrate found by Bruegger and colleagues may very well be confounded by the exogenous administration of resuscitation fluids and blood products in the animal model described. …