ACUTE-RENAL-FAILURE IN INTENSIVE-CARE UNITS - CAUSES, OUTCOME, AND PROGNOSTIC FACTORS OF HOSPITAL MORTALITY - A PROSPECTIVE, MULTICENTER STUDY

Objective: To assess the causes, the prognostic factors, and the outco me of patients with severe acute renal failure. Design: Prospective, m ulticenter study. Setting: Twenty French multidisciplinary intensive c are units (ICUs). Patients: All patients with severe acute renal failu re were prospectively enrolled in the study for a 6-month period. Seve re acute renal failure was defined by the following criteria: a) a ser um creatinine concentration of greater than or equal to 3.5 mg/dL (gre ater than or equal to 310 mu mol/L) and/or a blood urea nitrogen conce ntration of greater than or equal to 100 mg/dL (greater than or equal to 36 mmol/L); or b) an increase in blood urea nitrogen or serum creat inine concentration, such that the concentration is 100% above the bas eline value in patients with previous chronic renal insufficiency (ser um creatinine concentration of >1.8 mg/dL [>150 mu mol/L]), excluding those patients with a basal serum creatinine concentration of >3.4 mg/ dL (>300 mu mol/L). Interventions: None. Measurements and Main Results : Age, sex, previous health status and preexisting organ dysfunction, and type and origin of acute renal failure were recorded. The Simplifi ed Acute Physiology Score, the Acute Physiology and Chronic Health Eva luation (APACHE II) score, and the number of Organ System Failures wer e calculated on ICU day 1 and at the time of inclusion in the study. P rognostic factors were determined by univariate methods and stepwise l ogistic regression analysis. There were 360 patients in the study; 217 patients were admitted to the study at the time of ICU admission and 143 patients were admitted to the study after ICU admission. Only 41% of these patients were in good health 3 months before ICU entry. The r eason for admission was medical in 78% of cases. The type of acute ren al failure was prerenal (n = 61), renal (n = 282), or postrenal (n = 1 7). Renal replacement therapy was used in 174 patients. Two hundred te n (58%) patients died during the hospital stay. Using stepwise logisti c regression, seven variables were predictive of death. These variable s were advanced age, altered previous health status, hospitalization b efore ICU admission, delayed occurrence of acute renal failure, sepsis , oliguria, and severity of illness as assessed at the time of study i nclusion by Simplified Acute Physiology Score, APACHE II, or Organ Sys tem Failure. Conclusions: The hospital mortality rate of patients with severe acute renal failure in patients requiring intensive care remai ns high. In order to compare patient groups in further trials concerni ng acute renal failure, recorded characteristics of the population sho uld include age, previous health status, disease characteristics (init ial or delayed acute renal failure, oliguria, sepsis), and the severit y of the illness as assessed by physiologic scoring systems recorded a t the time of study inclusion.