Abstract
Objective There is recent interest in the association between hyperchloremic metabolic acidosis
and adverse outcomes. In vitro, hyperchloremia causes renal vasoconstriction and fall
in glomerular filtration rate (GFR). The objective of this retrospective, observational
study is to examine associations between chloride level at admission to pediatric
intensive care (PICU) and worst GFR and requirement for renal replacement therapy.
Materials and Methods All admissions to PICU between 2009 and 2019 who received invasive mechanical ventilation
and had blood gas analysis performed were included. Data analyzed included patient
characteristics (age, gender, diagnosis, pediatric index of mortality [PIM]-2 score);
results of initial blood gas; and maximum serum creatinine (then used to calculate
minimum GFR). Primary outcome measure was worst GFR during PICU stay. Secondary outcome
measures were requirement for renal replacement therapy and PICU mortality. Multivariable
regression analysis was used to assess if admission chloride level was independently
predictive of minimum GFR during PICU stay and to examine associations between hyperchloremia
(>110 mEq/L) at admission and requirement for renal replacement therapy after adjustment
for confounders.
Results Data were available for 2,217 patients. Median age was 16.4 months and 39% of patients
were hyperchloremic at admission to PICU. Admission chloride level was independently
predictive of worst GFR during PICU stay after adjustment for known confounders. Patients
with hyperchloremia were not more likely to require renal replacement therapy or die
than patients with normochloremia.
Conclusion Prospective studies are necessary to determine if high chloride, specifically chloride
containing resuscitation fluids, have a causal relationship with poor outcomes.
Keywords
hyperchloremia - chloride - glomerular filtration rate - pediatric intensive care
unit - outcomes
