Pre-renal Causes Of AKI

Etiology

  • Hypovolemia
  • Hypotension for any reason, including low cardiac output, sepsis, other
  • Renal artery stenosis
  • Hepato-renal, where kidney behaves as if hypo-perfused related to portal htn and very advanced liver disease
  • Cardio-renal, where very advanced heart failure contributes to acute (often on top of chronic) kidney injury
  • Pre-renal injury can be exacerbated by use of NSAIDs (inhibit prostaglandin formation--> decreased afferent arteriole dilation), ACE-I/ARBs (decreased efferent vasoconstriction), diuretics (hypovolemia), intravenous contrast for CT scans (decreased afferent dilation) or other direct renal toxins
  • Combined effect from multiple causes - this is common, in particular when there is pre-existing/chronic kidney disease