Acute Renal Failure - Causes, Symptoms, Treatment
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 azotemia (a rise in blood urea nitrogen [BUN] concentration). However, immediately after a kidney injury, BUN or creatinine levels may be normal, and the only sign of a kidney injury may be decreased urine production. Acute renal failure (ARF) is the rapid breakdown of renal (kidney) function that occurs when high levels of uremic toxins (waste products of the body’s metabolism) accumulate in the blood.ARF occurs when the kidneys are unable to excrete (discharge) the daily load of toxins in the urine.
Acute renal failure (ARF) is a common complication of critical illness, which is associated with high mortality and has a separate independent effect on the risk of death. Despite several advances in treatment and in our understanding of the pathogenesis of ARF, many aspects in this field remain subject to controversy, confusion and lack of consensus. Important aspects beset by such problems include the definition of ARF; the choice, validity and relevance of animal models of ARF; and the choice regarding appropriate physiological and clinical end-points for trials of new treatments of ARF.
Causes
The most common causes of acute renal failure are dehydration, serious illnesses that cause heart or liver failure, severe blood loss, shock, or traumatic injury such as a burn. It may also occur in: those with conditions that block the flow of urine, such as kidney stones, tumors, or enlarged or inflamed prostate gland; those with a blood infection (sepsis); or those with kidney damage caused by kidney disease or exposure to a toxic (poisonous) substance.
Symptoms and Signs
Initially, weight gain and peripheral edema may be the only findings. Often, predominant symptoms are those of the underlying illness or those caused by the surgical complication that precipitated renal deterioration. Later, as nitrogenous products accumulate, symptoms of uremia may develop, including anorexia, nausea and vomiting, weakness, myoclonic jerks, seizures, confusion, and coma; asterixis and hyperreflexia may be present on examination. Chest pain (typically worse with inspiration or when recumbent), a pericardial friction rub, and findings of pericardial tamponade may occur if uremic pericarditis is present.
Treatment
Once the cause is found, the goal of treatment is to restore kidney function and prevent fluid and waste from building up in the body while the kidneys heal. Usually, you have to stay overnight in the hospital for treatment. The amount of liquid you eat (such as soup) or drink will be limited to the amount of urine you can produce. You will be told what you may and may not eat to reduce the build-up of toxins normally handled by the kidneys. This diet may be high in carbohydrates and low in protein, salt, and potassium.
No overall benefit has been proven from the use of the synthetic analogue of atrial natriuretic factor, anaritide, in reducing the duration of or mortality from ATN. However, oliguric patients did appear to do better whilst non-oliguric ones did worse when treated with this agent in a large clinical trial.
