Epidemiology of acute renal failure in the intensive care unit

Abstract

Epidemiology is properly the study of disease and the distribution of disease in a defined population. Ideally, to allow rational comparison of disease in different populations at differing times, the diagnostic criteria that define a disease need to be precisely agreed. Acute renal failure (ARF) however, is a “broad church” with heterogeneity of causation and of outcome (Fig. 1). Review of the epidemiology of ARF is therefore hampered by the lack of a fixed definition for the clinical syndrome. In a recent review of 26 reports of postoperative ARF, no two studies used the same definition of ARF [11. Reported series have included patients with different causes of ARF, with widely variant manifestations of renal dysfunction, from minor increases in creatinine to the need for dialysis. Furthermore, in those patients who are dialysed, the indication for dialysis reported by different centres varies widely. Confusion in terminology also hampers easy analysis of the literature of ARF, particularly with the wide use of the pathological term “acute tubular necrosis” (ATN), as a clinical diagnostic category in reported series without further definition.