Management of early acute renal failure: focus on post-injury prevention.

PURPOSE OF REVIEW: In this review, we describe our current understanding of various aspects of secondary renal injury and its prevention. Secondary renal injury indicates any injury to the kidney, which occurs after an initial event has already triggered injury to the organ. RECENT
FINDINGS: Analysis of the literature reveals several important fields of possible intervention. First, blood pressure is considered important and hypotension is associated with renal injury. Avoiding hypotension is an important mechanism of renal protection from secondary injury. Similarly, a low cardiac output state should be promptly treated or prevented. Adequate volume resuscitation is also considered important although strong direct evidence for this intervention is not available. There is insufficient evidence to suggest that any drug can specifically increase renal blood flow in man independent of an effect on blood pressure or cardiac output. Specific kidney protective approaches have not yet been identified. Intensive insulin therapy possibly delivers renal protection and deserves further investigation. Modulation of the stress response appears attractive in experimental models but it has not been shown effective in man. Ischemic preconditioning is a useful strategy for renal protection in the experimental setting. An understanding of the mechanisms involved in ischemic preconditioning might assist in developing novel and effective interventions in man.
SUMMARY: The pillars of protection from secondary renal injury are similar to those needed to protect the kidney from primary injury: maintenance of adequate intravascular volume, cardiac output, and arterial blood pressure. Novel protective strategies such as intensive insulin therapy require further investigation.