Within days of registration: Serum creatinine < . mg/dL (. umol/liter) Serum creatinine =< . mg/dL ( umol/L) Serum creatinine < umol/L (< . mg/dL) or . x the upper limit of normal, whichever is less Creatinine < . mg/dl (= umol/L) or Serum creatinine =< . mg/dL or umol/L Serum creatinine =< . mg/dL or umol/L Serum creatinine =< . mg/dL or umol/L Serum creatinine =< . mg/dL or umol/L obtained =< weeks prior to enrollment Serum creatinine =< . mg/dL or umol/L Serum creatinine =< . mg/dL ( umol/L) Creatinine =< . mg/dL or umol/L Serum creatinine =< . mg/dL or umol/L Creatinine > umol/L ( mg/dL) Serum creatinine =< . mg/dL or umol/L Creatinine =< . mg/dL ( umol/L), or if > . mg/dL, calculated creatinine clearance >= cc/min) Serum creatinine =< . mg/dL or umol/L Serum creatinine =< . mg/dL or umol/L Creatinine > umol/L ( mg/dL) Serum creatinine =< . mg/dL or umol/L Serum creatinine =< mg/dL ( umol/L) and creatinine clearance >= ml/min Serum creatinine > . mg/dL ( umol/L) in females and > . mg/dL ( umol/L) in males; patients with serum creatinine values exceeding these limits are eligible for the study if their estimated glomerular filtration rates (GFR) are > ml/min/. m^ Within days prior to signing consent: Serum creatinine > . mg/dL or umol/L Serum creatinine =< umol/L (.mg/dL) Individuals with plasma creatinine > umol/L Plasma creatinine in excess of umol/L within days prior to surgery