title: Hydroxyethyl starch (HES) versus other fluid therapies: effects on kidney function.
abstract: BACKGROUND
  Hydroxyethyl starches (HES) are synthetic colloids commonly used for fluid resuscitation, yet controversy exists about their impact on kidney function.
  
  
  OBJECTIVE
  To examine the effects of HES on kidney function compared to other fluid resuscitation therapies in different patient populations.
  
  
  METHODS
  We searched the Cochrane Renal Group's specialised register, the Cochrane Central Register of Controlled Trials (CENTRAL, in The Cochrane Library), MEDLINE, EMBASE, MetaRegister and reference lists of articles.
  
  
  METHODS
  Randomised controlled trials (RCTs) and quasi-RCTs in which HES was compared to an alternate fluid therapy for the prevention or treatment of effective intravascular volume depletion. Primary outcomes were renal replacement therapy (RRT), author-defined kidney failure and acute kidney injury (AKI) as defined by the RIFLE criteria. Secondary outcomes included serum creatinine and creatinine clearance.
  
  
  METHODS
  Screening, selection, data extraction and quality assessments for each retrieved article were carried out by two authors using standardised forms. Authors were contacted when published data were incomplete. Preplanned sensitivity and subgroup analyses were performed after data were analysed with a random effects model.
  
  
  RESULTS
  The review included 34 studies (2607 patients). Overall, the RR of author-defined kidney failure was 1.50 (95% CI 1.20 to 1.87; n = 1199) and 1.38 for requiring RRT (95% CI 0.89 to 2.16; n = 1236) in HES treated individuals compared with other fluid therapies. Subgroup analyses suggested increased risk in septic patients compared to non-septic (surgical/trauma) patients. Non-septic patient studies were smaller and had lower event rates, so subgroup differences may have been due to lack of statistical power in these studies. Only limited data was obtained for analysis of kidney outcomes by the RIFLE criteria. Overall, methodological quality of studies was good but subjective outcomes were potentially biased because most studies were unblinded.
  
  
  CONCLUSIONS
  Potential for increased risk of AKI should be considered when weighing the risks and benefits of HES for volume resuscitation, particularly in septic patients. Large studies with adequate follow-up are required to evaluate the renal safety of HES products in non-septic patient populations. RIFLE criteria should be applied to evaluate kidney function in future studies of HES and, where data is available, to re-analyse those studies already published. There is inadequate clinical data to address the claim that safety differences exist between different HES products.
authors.affiliation: Department of Pediatrics and Child Health, University of Manitoba, FE-009 840 Sherbrook St, Winnipeg, Manitoba, Canada, R3A 1S1.
authors.forename: Allison B
authors.initials: AB
authors.lastname: Dart
authors.forename: Thomas C
authors.initials: TC
authors.lastname: Mutter
authors.forename: Chelsea A
authors.initials: CA
authors.lastname: Ruth
authors.forename: Shayne P
authors.initials: SP
authors.lastname: Taback
mesh_terms: D058186:Acute Kidney Injury / Q000139:chemically induced*; D001810:Blood Volume; D006801:Humans; D006895:Hydroxyethyl Starch Derivatives / Q000009:adverse effects*; D010952:Plasma Substitutes / Q000009:adverse effects*; D016032:Randomized Controlled Trials as Topic
chemical_list: D006895:Hydroxyethyl Starch Derivatives; D010952:Plasma Substitutes