Acute Renal Failure

Definition

Definition of Acute Renal Failure
Acute renal failure (ARF), or acute kidney injury (AKI), as it is now referred to in the literature, is defined as an abrupt or rapid decline in renal filtration function. This condition is usually marked by a rise in serum creatinine concentration or by azotemia (a rise in blood urea nitrogen {BUN} concentration).

Symptoms

Symptoms of Acute Renal Failure
Often, this kidney disorder does not display any symptoms and often go unnoticed. Some key indicators of acute renal failure include rapid heart rate, dizziness, loss of appetite and vomiting, flan pains, little or no urine.

Causes

Causes of Acute Renal Failure
The driving force for glomerular filtration is the pressure gradient from the glomerulus to the Bowman space. Glomerular pressure is primarily dependent on renal blood flow (RBF) and is controlled by combined resistances of renal afferent and efferent arterioles. Regardless of the cause of acute kidney injury (AKI), reductions in RBF represent a common pathologic pathway for decreasing GFR. The etiology of AKI consists of 3 main mechanisms.

Diagnosis

Diagnosis of Acute Renal Failure
The diagnosis can be done through blood urea nitrogen tests and creatinine. For causes that are not apparent, large volume blood test and urine examination may be necessary as well as ultrasonography of the renal tract to check for possible obstruction of the renal tract.

Treatment

Treatment of Acute Renal Failure
Measures to correct underlying causes of acute kidney injury (AKI) should begin at the earliest indication of renal dysfunction. A large proportion of the renal mass is damaged before any biochemical evidence of renal dysfunction is appreciated, because the relationship between the GFR and the serum creatinine level is not linear, especially early in disease; the rise of serum creatinine may not be evident before 50% of the GFR is lost.

The Acute Renal Failure Trial Network (ATN) Study, completed in 2008, was designed to compare clinical outcomes between patients allocated to an intensive dose versus a less-intensive dose of renal replacement therapy. No additional benefit (morbidity/mortality) was conferred to patients who received more intensive dialysis (either intermittent or continuous dialysis). The best evidence suggests that patients with dialysis-dependent AKI should receive at least 3 hemodialysis treatments per week with delivered Kt/V value of 1.2 or continuous hemodialysis (continuous venovenous hemodialysis or hemofiltration) of 20 mg/kg/h (prescribed).

Prognosis

Prognosis of Acute Renal Failure
The prognosis for patients with AKI is directly related to the cause of renal failure and, to a great extent, to the duration of renal failure prior to therapeutic intervention.

Prevention

Prevention of Acute Renal Failure
Consult with your doctor.