Renal Failure

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Acute Renal Failure Sudden loss of renal function that may be reversible
Causes of acute renal failure Illness, injury, or toxin that stresses the kidneys.
Classifications of acute renal failure Prerenal, intrarenal and postrenal depending on the location of the illness in relation to the kidneys
Prerenal failure Result of insufficient blood flow into the kidneys caused by shock, trauma, severe dehydration or cardiac disease
Intrarenal failure Result of direct toxic or traumatic injury to the kidney
Postrenal failure Results when an obstrucction from the lower urinary system causes backup of urine, which injures the kidneys
Chronic Renal Failure Long, usually slow process that involves a progressive loss of nephrons (loss of more than 75% of nephrons in each kidney to cause obvious illness)
Chronic renal failure to ESRD May take many years to progress from chronic renal failure to ESRD
Characterizatons of Chronic Renal Failure Proteinuria, Nocturia, Hypertension, Sodium retention, Anemia, Dyspnea, Uremic symptoms, Nausea and vomiting
Proteinuria Leaking of protein through the glomeruli in to the renal tubules, and then into the urine
Nocturia Night time urination due to loss of the ability to concentrate the urine
Hypertension High blood pressure
Sodium retention Leading to edema, or water retention/swelling
Anemia A shortage of red blood cells
Dyspnea Difficulty breathing
Uremic Symptoms such as fatigue, loss of appetite, sleep disorders, mental changes, itching and skin disorders
Nausea and vomiting Occurs late in the course of renal failure
Diagnosing chronic renal failure Symptoms may not arise until it is advanced. Regular blood tests for urea and/or creatinine can identify renal failure iin the early stages when treatment to slow its progress will be most effective
Stage 1 kidney failure
Mild renal insufficiency
Pt has few or no symptoms
Stage 2 kidney failure
Moderate renal insufficiency
Creatinine clearance is 50% normal
Few, if any symptoms
Anemia is present
Stage 3 kidney failure
Marked renal insufficiency
Creatinine clearance drops to 10-15% of normal
Few or no symptoms
Anemia is present
Treatment for stage 3 kidney failure
Phosphate binders, restricted protein diet, and prep. for dialysis or transplant
Oral bicarbonate supplements to help maintain normal acid/base balance and erthyropoeitin for control of anemia
Stage 4 kidney failure
ESRD
The creatinine clearance is 10mL/min or less
Uremic symptoms are present
Dialysis and transplant is needed to sustain life

Creatinine Clearance
a measure of the body's ability to remove waste from the blood
Stalling progression of kidney failure BP control, medications and diet have been developed to slow the course of some forms of chronic renal failure
Causes of chronic renal failure Diabetes, hyptertension, glomerulonephritis, cystic disorders or polyssistic kidneys, drug toxicity, interstitial nephritis, obstruction
Leading cause of ESRD Diabetes (diabetic nephropathy)
Type 1 diabetes body's immune system destroys the insulin-producing cells in the pancreas
Type 2 diabetes body does not make enough insulin or cannot use insuling properly
Microalbuminuria
Presence of tiny amounts of albumin, or protein, in the urine
Sign of kidney damage (blood tests)
Complications of dialysis with diabetic pts Diabetes can cause high bp, heart disease, small blood vessel disease that can cause leg ulcers andl imb loss, blindness, and digestive disorders which make treatment of kidney disease more complicated
2nd most common cause of ESRD Hypertension (high bp)
Hyptertension symptoms may cause no symptoms until it is very advanced, therefore many people are not treated until damage is done to the kidneys, heart, blood vessels and eyes
High BP and nephrons High BP puts continuous stress on the nephrons, leading to loss of kidney function
Renal artery stenosis
Narrowed renal arteries
Can lead to hypertension by reducing blood flow to the kidneys causing kidneys to produce more of the substances that raise bp
Glomerulonephritis
inflammation of the glomeruli
damages the glomeruli, sometimes enough to cause chronic renal failure
Polycystic kidney disease (PKD)
inherited disease that causes large, fluid filled cysts to develop in the kidneys
cysts can become so large and numerous that normal kidney tissue is crowded out, therefore kidney function ceases (only 50% reach this point)
Drug toxicity
an increasing # of pt's need dialysis because of drug or medication use has destroyed their kidneys
NSAIDS, ibuproen, and naproxen if not taken correctly can cause kidney damage
Heroin nephropathy the damage heroin can do to the renal system
Interstitial nephrititis
damage to the supporting structure of the kidneys
ex. allergic reaction to antibiotics
Obstruction Malformation of the lower urinary tract caused by congenital anomalies (birth defects), kidney stones or scarring from infections can cause urine to back up into the structures of the kidney and injure them
Other causes of chronic kidney failure collagen-vascular diseases (lupus), cancer, congenital defects, AIDS, and sickle cell disease.
Uremia
Urine in the blood
Pts whose kidneys are failing may have severe uremia and even pts with dialysis have some uremia since dialysis is only about 15% as effective as healthy kidneys
Symptoms of uremia
Pallor of the skin, edema, high bp, loss of appetite, nausea and vomiting, itching, restlessness, shortness of breath, fatigue and weakness, and mentan changes.
Pallor of the skin
yellow-gray appearance
caused by a pigment called urochrome, which is retained in the body instead of being excreted in the urine
People with long term renal failure almost universally suffer from 2 complicating conditions:
Anemia and renal osteodystrophy
Other complications:
pericarditis, electrolyte imbalance, nerve damage, amyloidosis, carpal tunnel syndrome, itching, sleeping problems, bleeding abnormalities and reproductive system changes
Anemia shortage of RBCs and therefore a shortage of hemoglobin
Hemoglobin protein component of RBCs that carries oxygen to all the cells in the body
Symptoms of anemia in renal patients fatigue, dizziness, heart problems, disordered thoughts, erectile difficulties, and lack of energy
Causes of anemia in renal patients inadequate amounts of erythropoietin, iron deficiency and vitamin deficiency
Erythropoietin (EPO)
a hormone produced by the kidneys that signals the bone marrow to make red blood cells
therefore, inadequate EPO results in a shortage of RBCs
Blood tests to assess anemia
Hemoglobin (measures oxygen carrying red pigment in RBCs)
Hematocrit (measure of RBCs in blood stated as a percent of RBC per total blood volume)
Maintaining Hemoglobin and Hematocrit in dialysis pts
regular administration of Epogen (epoetin alfa)
Pts must have an adequate amount of iron and vitamins to permit the Epogen to work (must monitor levels and prescribe vitamins as neccessary)
Iron deficiency
Iron is needted to make RBCs
Pts with renal failure lose iron containing blood with each lab test and dialysis treatment
"Blood loss=iron loss
Occult (hidden) blood loss (hemorrhoids, ulcers, improper anticoagulation (anticlotting) during dialysis)
Many dialysis pts need iron infusions
Vitamin deficiency
Vitamin B12, folic acid and pyridoxine promote good blood cell growth and maturity
Dialysis removes these vitamins along with the wastes
Many dialysis pts need vitamin supplements AFTER dialysis so they are not dialyzed out
Renal Osteodystrophy
Type of bone disease that occurs in renal pts because when kidneys fail, they stop making calcitrol, and they stop excreting excess phosphorus in the urine
Without calcitrol, calcium absorption from food is impaired
Because phosphorus is so abundant, it builds up in the body, even though it is not absorbed as well as before
If there is too little calcium and too much phosphorus in the blood: a feedback mechanism kicks in to correct the problem: the parathyroid glands secrete PTH (PTH raises blood calcium levels) PTH triggers the kidneys to produce calcitrol so more calcium will be absorbed, and the calcium balance will be restored.
When failing kidneys cannot make calcitriol:
the parathyroid glands continue to pump out PTH to solve the problem
PTH acts on the bones to release needed calcium into the bloodstream so the body can function
Over long term, too much calcium is pulled out of the bones, and the bones become weak
Secondary hyperparathyroidism
overproduction of PTH due to renal failure
This is a cause of hyperparathyroid bone disease (bone remodeling rates are greatly increased. The bones are poorly mineralized and fractures may occur)
Pericarditis inflammation of the membrane or sac that surrounds the heart
Effects of pericarditis persistent pain in the center of the chest that may be relieved by sitting up and taking deep breaths
Treatment of pericarditis After a period of thorough dialysis, symptoms should diminish, however some pts need surgery
Electrolytes
substances that break apart into ions, electrically charged particles, when dissolved in a fluid.
found in bodily fluids and inside cells and are involved in many basic cell functions, including the sending of important signals between different types of cells
Electrolyte Imbalance
Electrolyte levels in the body are normally controlled in part by the kidneys.
Renal failure can disturb the normal balance between elimination and reabsorption of electrolytes in the kidneys, and lead to imbalances. This can have serious effects on many body functions
Most important electrolytes to consider in uremic pts Sodium, potassium, calcium, phosphate, magnesium, and bicarbonate
Sodium Important for maintaining the body's water content and fluid balance and plays a role in regulating the acid-base status of the body
Hypernatremia
higher than normal level of sodium in the blood
can cause edema (accumulation of water in various tissues), crenation (shriveling) of RBCs
Symptoms of hypernatremia excessive thirst, high bp, headaches, confusion, seizures and coma
hyponatremia
low blood sodium levels
Water moves into cells, RBCs may swell to the point of hemolysis (bursting)
Symptoms of hyponatremia low bp, muscle cramping, headaches, nausea, vomiting, tremors, seizures and coma
Potassium
major role in function of nerves and muscles, including contraction of heart muscle
Most of bodys potassium is found in muscle cells
Hyperkalemia
is a high level of potassium in the blood
can cause serious or even fatal changes in the heart rhythm
Symptoms of hyperkalemia
extreme muscle weakness, abnormal heart rhythms
sometimes no warning signs before cardiac arrest
Hypokalemia
lower than normal blood potassium level
unusual in kidney pts, but could happen if pt has vomiting and diarrhea or too much removed by dialysis
Symptoms of hypokalmia fatigue, muscle weakness, paralysis, respiratory failure, abnormal heart rhythms and cardiac arrest
Calcium
found in the body within the bones and teeth
Small amounts of calcium is vital for regulating many cell activities including blood clotting, enzyme regulation, hormone action and function of nerves and muscles
Hypercalcemia
Presence of high levels of calcium in the blood
Pts may have loss of appetite, nausea, vomiting, and abdominal pain, central nervous system may also be affected, and the pt may experience confusion, irritability, delierium, and even coma
Hypocalcemia
low blood calcium levels
primarily affecgts the nervous system
pt. may have dementia, depression, numbness, seizures, tetany (muscle spasms and pain), high levels of pth contributing to bone disease in renal failure
Phosphate important structural component of cell membranes and bones, and many essential cellular reactions (especially those involved with energy metabolism) depend on phosphate
Hyperphosphatemia
High blood phosphorus levels
Leads to itching, bone damage and 2ndary hyperparathyroidism
Asymptomatic until late in the disease
Hypophosphatemia
below normal phosphate in the blood
Muscle weakness and osteomalacia (softening of the bones) as well as more serious neuromuscular problems and come
Asymptomatic until late in the disease
Magnesium required for many cellular reactions such as synthesis of proteins, fats, and carbs and plays an important role in contraction of muscles
Hypermagnesemia
High blood magnesium levels may be seen in pts who take meds containing mg.
Interferes with the transmission of nerve impulses, leading to loss of reflexes, low bp, respiratory depression and sleepiness.
Bicarbonate
base reabsorbed by the kidneys that helps maintain normal body pH by neutralizing the acids that are formed when proteins are broken down and used by cells.
In kidney pts, the acid-base buffering system is disturbed, and there is a relative lack of bicarbonate
Bicarbonate deficit
causes the condition known as metabolic acidosis, or high blood acid levels
the main symptom of metabolic acidosis is deep, rapid breathing, which is the bodys way to compensate for the build-up of acids in the bloodstream.
Neuropathy
Nerve damage
Build up of waste produts in the blood from inadequate dialysis or problems with their vascular accesses
Symptoms of neuropathy
tingling, burning, numbness, weakness, and pain in the hands and feet
In most cases can be treated with dialysis and adherence to diet
Amyloidosis condition in which amyloid (starch like protein substance) deposits in the bones or joints cause pain, carpal tunnel syndrome and arthritis like symptoms
Carpal Tunnel Syndrome
painful condition of the hand caused by compression of nerves in the wrist
Symptoms: pain, numbness, tingling and limited movement of the hand
Due to vascular access complications or amyloidosis
Itching Severe and persistent itching or pruritus may develop due to dry skin, build up of calcium or phosphorus in the skin
Sleeping problems Restlessness and the inability to sleep (insomnia) caused by calcium and phos imblances, stress of illness, anemia, depression, and/or build up of wastes in the body
Bleeding abnormalities
due to complex bloo factor changes
Signs include easy bruising, GI bleeding ,blood in stools, nose bleeds, etc.
Can be minimized with consistent and effective dialysis (watch heparin)
Reproductive system changes Fertility may be reduced, men impotent, women may stop menstruating