Table 1.

Operational definitions of risk factors, hazard tiers (tranches), and early Cr elevation

Classification of risk factors for AKI (definitions in Supplemental Table 1)
 Chronic major
  Advanced age
  Diabetes mellitus
  Cardiovascular disease
 Chronic minor
  Morbid obesity
  Cerebrovascular accident
  High-risk surgery
  Nephrotoxin exposure
Classification of patients into hazard tranches
 Hazard tier (tranche) 1: very high risk
  Patients with septic shock, or
  Patients receiving vasopressors and mechanical ventilation
 Hazard tier (tranche) 2: high risk
  1 acute risk factor+1 major chronic risk factor, or
  1 acute risk factor+2 minor chronic risk factor, or
  2 acute risk factors
 Hazard tier (tranche) 3: moderate risk
  1 major chronic risk factor or 1 acute risk factor (but not both), or
  Multiple chronic major and minor risk factors without acute risk factors
Within each hazard tier, early Cr elevation is present if there is an increase in serum creatininea
 Hazard tier 1 (very high risk): ↑ 0.1 mg/dl
 Hazard tier 2 (high risk): ↑ 0.3 mg/dl
 Hazard tier3 (moderate risk): ↑ 0.4 mg/dl
  • Classification of risk factors into chronic major, chronic minor, and acute are adapted from reference 26. Cr, creatinine.

  • aChanges in serum creatinine were calculated daily throughout the intensive care unit stay.