Acute Renal Failure

 

Acute renal failure (ARF) is a rapid decrease in renal function.  It leads to an accumulation of metabolic waste in the body.  ARF acute syndrome may be reversible.

 

 

Functions of the kidney.

• Excretion of  waste
• Regulate water and salt
• Maintenance of acid balance
• Hormone secretion

Pathophysiology

This process of ARF is related to the cause of the sudden decrease in kidney function and the involved site or sites of the kidney.   Hypoperfusion, toxins, tubular ischemia, infections, and obstruction have diferent efects on the renal system.

With acute hypoperfusion,  urine volume results in oliguria [urine output les than 40/ml day.] Renal failure is present when BUN and creatinine levels rise and the ratio betwen the two remains constant.

Characteristics of Acute renal failure

Onset is sudden [hours to days]

Nephron involved [50%]

Duration [2-4 wks; less than 3 mo]

Prognosis [god for retun of renal function with suportive care; high mortality in some situations]

Types of Acute Renal Failure

Prerenal azotemia- can be reversed by:

establishing normal intravascular volume

increasing blod presure

increasing cardiac output

[Prolonged, untreated hypoperfusion can lead to severe ischemic injury and intrarenal failure.]