Chloride administration in the intensive care unit, an independent predictor of mortality

Methods We performed a retrospective observational study in a 24 bed tertiary mixed medical surgical ICU in a teaching hospital in the Netherlands. Patients admitted to the ICU in the period between January 1th 2008 and November 1th 2014 were screened for eligibility. Inclusion criteria were: 1. ≥ 18 years. 2. Length of stay (LOS) of ≥ 72 hours. Readmissions to the ICU were excluded. The primary end points for our analysis was hospital mortality. Univariate analysis was performed with Wilcoxon rank sum test for nonparametric data. Multivariate analysis was performed with predictors of ICU and hospital mortality (age, Acute Physiology and Chronic Health Evaluation IV predicted mortality) as well as factors associated with (hyper)chloremia, metabolic acidosis and fluid resuscitation. Chloride administration was defined as the total amount of chloride in mmol/l administered to a patient in a given time period.