Pre-renal Causes Of AKI

Your Path

  • 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 (e.g. CKD from DM and HTN)

Risk Factors

  • Preexisting kidney disease (CKD for any reason)
  • Diabetes, atherosclerosis, HTN

Symptoms

  • Vary with etiology
  • Volume loss: poor POs, diarrhea, bleeding, vomiting
  • Hypotension: lightheaded, dizzy, orthostatic symptoms, syncope
  • Sepsis: fevers, chills, pain (based on site of infection)
  • Sometimes combination of above symptoms (e.g. sepsis leading to hypotension)

Physical Exam Findings

  • Findings vary based on etiology
  • May have fever (if infectious), low BP, elevated heart rate, confusion
  • May appear acutely ill
  • May have findings associated with risk factors: e.g. vascular dz (diminished pulses), neuropathy, edema