title: Higher serum chloride concentrations are associated with acute kidney injury in unselected critically ill patients.
abstract: BACKGROUND
  Chloride administration has been found to be harmful to the kidney in critically ill patients. However the association between plasma chloride concentration and renal function has never been investigated.
  
  
  METHODS
  This was a retrospective study conducted in a tertiary 24-bed intensive care unit from September 2010 to November 2012. Data on serum chloride for each patient during their ICU stay were abstracted from electronic database. Cl0 referred to the initial chloride on ICU entry, Cl(max), Cl(min) and Cl(mean) referred to the maximum, minimum and mean chloride values before the onset of AKI, respectively. AKI was defined according to the conventional AKIN criteria. Univariate and multivariable analysis were performed to examine the association of chloride and AKI development.
  
  
  RESULTS
  A total of 1221 patients were included into analysis during study period. Three hundred and fifty-seven patients (29.2%) developed AKI. Cl(max) was significantly higher in AKI than in non-AKI group (111.8 ± 8.1 vs 107.9 ± 5.4 mmol/l; p < 0.001); Cl0 was not significantly different between AKI and non-AKI patients; Cl(mean) was significantly higher in AKI than non-AKI (104.3 ± 5.8 vs 103.4 ± 4.5;  = 0.0047) patients. Cl(max) remained to be associated with AKI in multivariable analysis (OR: 1.10, 95% CI: 1.08-1.13).
  
  
  CONCLUSIONS
  Chloride overload as represented by Cl(mean) and Cl(max) is significantly associated with the development of AKI.
authors.affiliation: Department of Critical Care Medicine, Jinhua Municipal Central Hospital, Jinhua Hospital of Zhejiang University, 351#, Mingyue Road, 321000 Jinhua, Zhejiang Province, China. zh_zhang1984@hotmail.com.
authors.forename: Zhongheng
authors.initials: Z
authors.lastname: Zhang
authors.forename: Xiao
authors.initials: X
authors.lastname: Xu
authors.forename: Haozhe
authors.initials: H
authors.lastname: Fan
authors.forename: Danyu
authors.initials: D
authors.lastname: Li
authors.forename: Hongsheng
authors.initials: H
authors.lastname: Deng
mesh_terms: D058186:Acute Kidney Injury / Q000097:blood* / Q000401:mortality*; D015415:Biomarkers / Q000097:blood; D002681:China / Q000453:epidemiology; D002712:Chlorides / Q000097:blood*; D016638:Critical Illness; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D015203:Reproducibility of Results; D012307:Risk Factors; D012680:Sensitivity and Specificity; D015996:Survival Rate
chemical_list: D015415:Biomarkers; D002712:Chlorides