Nursing assessment and management of acute renal failure

Renal Failure

Main Functions of the Kidneys

The kidneys are bean-shaped organs, 12 centimeters long, which lie at the sides of the spinal column behind the abdominal cavity (Merck 2010). Their main function is to maintain the proper balance of water and minerals in the body. Their other major functions include filtration and elimination of wastes and toxins, regulation of blood pressure and secretion of some hormones. The amount of water taken into the body must match the amount being eliminated. If the balance is not maintained, water will accumulate fast and illness or death may occur. Excess water will dilute the body's electrolyte and inadequate amount will concentrate electrolytes. The kidneys regulate and help maintain the precise concentrations (Merck).

The kidneys' second major function consists of filtration and excretion (Merck 2010). They pass out urea, a main waste product from protein metabolism. Urea moves through the glomerulus and into the tubuluar fluid and leaves the body as urine. Metabolic waste products, such as acids, toxins and drugs are also eliminated through urine (Merck).

A third major function is the regulation of the body's blood pressure (Merck 2010). Blood pressure tends to increase when too little sodium is excreted. The kidneys also produce the enzyme called rennin. They secrete this hormone into the blood stream when blood pressure drops below normal levels. The hormone activates the rennin-angiotensin-aldostrerone system, which responds by raising blood pressure. Persons suffering from kidney failure are likely to have high blood pressure (Merck).

The kidneys secrete other hormones to regulate other important functions like the production of red blood cells and bone growth and maintenance. One such hormone is erythropoietin, which stimulates red blood production in the bone marrow (Merck).

Two Potential Problems and Care Plans

The four most common, often called the "fatal four," are aspiration, dehydration, constipation and epileptic seizures (DHS 2008). They occur most frequently among those with developmental disabilities, leading to more severe illness and even death. The first 3 often go unnoticed among disabled persons who are usually unable to communicate their discomfort. And sudden and continuing epileptic seizures increase the risk of hospitalization and even death (DHS).

Aspiration consists of inhaling food, fluid, saliva, medication or another foreign object into the trachea and lungs (DHS 2008). The material can be introduced into the stomach or from the stomach, back to the throat. If the person stops breathing, CPR should be performed and 911 should be called. All feeding should be stopped immediately and restarted when health care professional gives permission. In the meantime, the person should be kept in an upright position and encouraged to cough. In the meantime, a swallowing specialist should be consulted if symptoms show up. A physician's order to change diet consistency, texture or consistency should be obtained. Eating should be done more slowly with small bite sizes. The patient's physical position should be kept upright 45 minutes after meals for 45 minutes. His bed should be elevated 30-45degrees. No food or fluids should be given 2-3 hours before bedtime. Medications to empty the stomach should be considered. An aspiration protocol and written instructions on these matters should be prepared (DHS).

Dehydration happens when fluid intake is insufficient (DHS 2008). The body then loses fluid more than it replaces. If the patient cannot drink safely, a health care professional should be called to administer intravenous fluids. In the meantime, the patient should be encouraged to drink 8-10 glasses of fluid or water every day, according to body weight. If he is reluctant, he may eat foods with high fluid content, such as gelatin, watermelon, puddings, yogurt or ice cream. If he very active, works hard, has a fever or sweats heavily, he needs more fluids. He needs less fluid if he has had cardiac or kidney disease. A health care professional should evaluate a patient with dysphagia. Protocol should include clear instructions on fluid requirements; minimal amount of daily fluid intake; monitoring intake and output; and signs and symptoms (DHS).

Nursing Management of Acute Renal Failure Phases

Renal failure often goes through four phases and the nurse must detect these phases in developing appropriate plan of care (Hudson 2007). As regards elimination and nutrition, nursing assessment and intervention should focus on the mild reduction of normal daily urine output in the onset phase; 24-hour urine total of 400 ml or less, metabolic acidosis, anorezia, vomiting, diarrhea and vomiting at the oliguric/anuric phase; urine output of 3-5 liters in a 24-hour period during the diuretic phase; and 1,500-1,800 during the recovery phase. The nurse should continue monitoring fluid volume overload for a decrease or temporary discontinuation of replacement fluid. She should also closely monitor electrolyte and acid-base imbalances to watch if replacement becomes necessary (Hudson).

The nurse should carefully watch changes in urine elimination, aimed at making the patient euvolemic and has no more symptoms of fluid deficit or overload (Hudson 2007). Urine output should be 30 ml per hour and no symptoms of deficit, such as dry mouth, hypotension, poor skin turgor or delayed capillary refill. For eating and drinking, the patient's diet should be altered to less than required but to remain balanced in nutrition and fluids and his weight kept within normal limits (Hudson). #