The Pathophysiology of Acute Renal Failure

Explain the pathophysiology of acute renal failure. Include prerenal intrarenal and postrenal causes.

According to the Mayo Clinic Staff (2012), acute kidney renal failure occurs abruptly when your kidneys lose their filtering abilities and cannot filter waste products from your blood. This is also known as acute renal failure or acute kidney injury. When this happens, high levels of waste may become accumulated in your blood and will alter your bloods chemical make up causing them to get out of balance. This failure or injury could happen rapidly over a few hours or a few days and can become fatal. Mostly people who are hospitalized and who are critically ill will need intensive care. If you take care of your body, acute kidney may be reversible and you may recover normal kidney function.

Prerenal kidney failure causes could be any condition that reduces renal perfusion and causes a decreased glomerular filtration rate. If prerenal is identified and treated correctly, it may be reversible. Some conditions that may contribute to prerenal kidney failure are: fluid shifts related and secondary to burns, hypertension, and reduced cardiac output in patients with congestive heart failure. If the main cause continues to affect renal perfusion this may lead to ischemic damage to the nephrons (Ludwig, Mathews, Gregg 2012).

Intrarenal kidney failure causes are actual damage to the nephrons and the functions of the tissues in the kidneys. This damaged could be grouped together under kidney disease or acute tubular necrosis. ATN could be reversible but it may take weeks or months before adequate perfusion returns (Ludwig, Mathews, Gregg 2012).

Postrenal kidney failure is caused by obstruction to the urine flow or excretion. Common problems would tumors, benign prostatic hypertrophy (BPH), or kidney stones. Intrarenal failure, nephron damage could occur if this is left untreated (Ludwig, Mathews, Gregg 2012).

What diagnostic exams would be used to diagnose acute renal failure? How do these tests change as renal failure progresses through its 3 stages? Discuss, compare and contrast the 3 stages.

To have a better understanding of your patients particular case with acute kidney failure you would want to gather a patient history to see if they have used any nephrotoxic medications or have had systemic illnesses in the past that may have been related to poor perfusion in their body. The laboratory tests you would want to pay attention to would be a complete blood count, urinalysis, ultrasound, glomerular filtration rate and a measurement of serum creatinine and potassium level (Rahman, Shad, Smith 2012).