Acute Kidney Failure

Recent studies have shown that the incidence of acute kidney failure is increasing in hospitals and patient populations in the United States, likely due to more elderly and more ill patients.

Acute Kidney Failure Overview

Reviewed: May 7, 2014

Kidneys are bean-shaped organs, each about the size of a fist. The kidneys are located near the middle of the back just below the rib cage and are sophisticated reprocessing machines. Each day, an person's kidneys process about 200 quarts of blood to sift out about 2 quarts of waste products and excess water. These wastes and water become urine which then exits the body through urination. Wastes that are present in our bloodstream, come from the normal breakdown of active tissues, such as muscles and from food sources. The body needs food for energy and internal repairs. Once the body has taken all it needs from the foods we ingest, wastes are sent to the blood. If our kidneys did not remove them, these wastes would then build up in the blood and go on to damage the body.

Acute kidney failure is a rapid loss the kidneys' ability to filter the blood and maintain the body's fluid and electrolyte balance. This can be caused from a variety of factors including an accident or injury, poison or trauma.

Acute kidney failure occurs in about three to seven percent of the 37 million yearly admissions to United States hospitals, or about 1 to 2.6 million people. 

It usually occurs in three settings: Loss of blood flow to the kidneys (blood loss, low blood pressure from heart failure, hardening of the renal arteries and blood clots), damage to the kidney tissue (from medications, infections, poisons), and obstruction of urine flow (enlarged prostate, urinary stones, bladder cancers, obstruction of the urethra). It is a medical emergency that can result in chronic kidney failure or death if left untreated.

Symptoms can be sudden, and are dependent on the type of kidney failure occurring. Usually, some combination of headache, fatigue, nausea, and loss of appetite is common. Irregular heartbeat, blood in the urine, seizures, swelling of the feet, and pain in the flanks may also occur.

Diagnosis is made by testing the blood and sometimes ultrasound and CT scan. Treatment is aimed at eliminating the underlying cause of kidney failure, for example, in fluid loss, restoring fluids and electrolytes; in injury, removing the offending drug; in blockage, removing the blockage. 

Acute Kidney Failure Symptoms

Symptoms of acute kidney failure can hit suddenly and should not be ignored. However, some symptoms of acute kidney failure can be mistaken for other milder conditions such as the common flu, so if you begin to experience symptoms, make sure to visit your doctor so you can get the correct diagnosis. If you know you have received recent trauma such as a hard hit directly to the kidneys and are experiencing symptoms, seek medical help immediately.

Symptoms generally include a combination of headache, fatigue, nausea and loss of appetite. Pain in the flanks, irregular heartbeat, blood in the urine, seizures, swelling of the feet and leg cramps are also possible. These problems may be caused by waste product build up within the blood, a condition called uremia.

The kidneys also make hormones and balance minerals found in blood. When the kidneys stop working, most people develop conditions that affect the blood, bones, nerves and skin. Therefore, in addition to the above symptoms, other signs include itching, sleep problems, restless legs, weak bones, joint problems and depression. 

If you are experiencing symptoms that are associated with acute kidney failure, talk to your doctor right away.

Acute Kidney Failure Causes

The cause of acute kidney failure comes from acute kidney injury or AKI. This usually occurs when direct injury or impact affects the body's kidneys. Losing a lot of blood can cause sudden kidney failure as well as certain drugs or poisons. These cause sudden drops in kidney function.

The word acute refers to conditions that happen suddenly and last a short time. Acute is the opposite of chronic which refers to long lasting conditions. Acute kidney injury is the sudden and temporary loss of kidney function. Typically, acute kidney failure occurs in three settings: loss of blood flow to the kidneys (from blood loss, low blood pressure from heart failure or hardening of the renal arteries and blood clots), damage to the kidney tissue (from medications, infections or poisons), and obstruction of urine flow (from enlarged prostate, urinary stones, bladder cancers or an obstruction of the urethra).

When acute kidney failure occurs, the kidneys are suddenly unable to filter the blood of unnecessary wastes and therefore becomes unable to maintain the body's fluid and electrolyte balance. A build up of wastes occurs as the kidneys are unable to push them out into the bladder to be disposed of through urination.

Acute Kidney Failure Diagnosis

Diagnosis of acute kidney failure may come by the patient seeking medical attention following a trauma or injury to the kidney area. This sudden trauma is known as acute kidney injury (AKI). AKI is the sudden and temporary loss of kidney function. 

Additional and scientific diagnosis is available by your doctor or health care professional. A diagnosis can be determined by testing the blood chemistry through the taking of a patient's blood sample. An ultrasound and CT scan can also be used to see the kidney in greater detail to decipher the damage.

A blood pressure measurement can also aid your doctor in finding more about your kidney health. A normal and healthy individual would have a blood pressure reading of 120/80 or below. Microalbuminuria is an additional test which detects the presence of a protein within the blood known as albumin. Microalbuminuria can tell if small amounts of albumin leak into the urine which indicates deteriorating kidney function. A urine sample will be taken for this test and your doctor map use a dipstick to test for the presence or absence of these proteins.

A more specific and sensitive test for this protein albumin in the urine uses laboratory measurement and calculation of the protein-to-creatinine or albumin-to-creatinine ratio. Creatinine is another waste product in the blood created by the normal and usual breakdown of muscle cells during activity. Healthy kidneys take creatinine out of the blood and put it into the urine to promptly leave the body. However, when the kidneys are damaged or not working properly, this waste builds up in the blood.

Your doctor may also use a GFR or glomerular filtration rate to determine how efficiently the kidneys are filtering wastes from the blood. A traditional GFR calculation requires an injection into the bloodstream of a substance that is later measured in a 24-hour urine collection. An individual's blood urea nitrogen level can also aid doctors in making a diagnosis. Blood carries proteins to cells throughout the entire body, after the cells use the protein the remaining waste product is returned to the blood as urea, a compound containing nitrogen. Healthy and fully functional kidneys take urea out of the blood and put it into the urine. However, with kidneys not working properly, the urea will stay in the blood. A deciliter of normal blood contains 7-20 milligrams or urea. If a person's blood urea nitrogen level is more than 20 mg/dL, the kidneys may not be working at full strength.

Living With Acute Kidney Failure

Living with acute kidney failure takes diligence and dedication as well as promptness to receive proper medical attention before the condition transitions to a chronic or long lasting one. 

It is important to remember that a blunt force trauma is not the only way the condition can be caused. Reactions to certain medications, heart failure, infections, enlarged prostate, urinary stones, bladder cancers and obstructions in the urethra can also cause acute kidney failure. If you have any of the above factors and experience symptoms such as headache, fatigue, nausea and loss of appetite, seek medical attention.

Recovering from the trauma of acute kidney failure may require the assistance of others. Incorporate loved ones into your new healthy lifestyle in order to stick to it in a more permanent manner. Eat foods high in fiber and low in fats and focus on limiting your intake of potassium, protein and sodium. Consult your doctor on additional preventative measures as to avoid further kidney injury and restore the health and balance to your organs.

Acute Kidney Failure Treatments

Treatment for acute kidney failure varies from treatment for chronic kidney failure, which may come as a result of longtime kidney disease. Treatment for acute kidney failure typically revolves around treatment of the injury which initially caused the condition.

In terms of fluid loss, which may come as a result of kidney trauma, fluid and electrolytes are reintroduced back into the body. If the body is experiencing a reaction to a certain pharmaceutical or other medication, the offending drug is removed. When blockage occurs, doctors and health care professionals remove it.

As you seek treatment, your doctor may recommend a change in diet until your kidneys are fully functional again. This may include a decrease in sodium, protein, potassium and phosphorus ingestion as well as quitting smoking. If the initial kidney injury resulted in a large amount of blood loss, your doctor may prescribe pharmaceuticals or injections to bring up the iron levels in your bloodstream.

Based upon the severity of your condition, your doctor may recommend hemodialysis, a treatment that uses a machine to circulate blood through a filter outside of the body. This procedure essentially cleans the individual's blood of wastes. During treatment, the blood travels through tubes into the dialyzer which then filters out wastes such as extra salt and extra water. The cleaned blood flows through another set of tubes back into the body. Hemodialysis is usually performed at a dialysis center three times per week for 3-4 hours.

Acute Kidney Failure Prognosis

Acute kidney injury, which causes acute kidney failure, can cause chronic (long lasting) kidney failure if left untreated so it is essential to seek medical assistance if you have sustained damage from trauma to your kidneys.

Because acute can mean temporary harm to those organs, you may wish to ask your doctor or health care professional what you can do on your own to aid in your recovery. Your doctor may recommend certain strategies to accompany medical treatment such as a change in diet or activities to avoid as to remain injury free. During hemodialysis, you should watch how much fluid you drink and avoid eating foods with excess amounts of sodium, potassium and phosphorus.

Even after recovery from your acute kidney failure, you may wish to change your lifestyle in order to keep your kidneys healthy and avoid further damage. Start a regular exercise routine and get into the habit of making more time for sleep each night. Afford saturated fats in your diet and lower the amount of sodium, potassium and protein you eat daily.