Pathophysiology Disorders of Renal Function

Accumulation of nitrogenous wastes such as urea in the circulatory system is an early sigh of chronic kidney disease (CKD). The nurse knows that normal levels of urea in blood are approximately:

20 mg/dL (7.14 mmol/L)

The nurse is educating a client about renal disease. Which percentage of cardiac output perfuses the kidneys?

22% to 25% Explanation: In the adult, the kidneys are perfused with 1000 to 1300 mL of blood per minute, or 22% to 25% of the cardiac output; 10% to 15% and 15% to 20% represent a decreased percentage; 27% to 30% is an increased percentage.

Glomerulus

A ball of capillaries surrounded by Bowman's capsule in the nephron and serving as the site of filtration in the vertebrate kidney.

A client has been given the diagnosis of diffuse glomerulonephritis. They ask the nurse what diffuse means. The nurse responds:

All glomeruli and all parts of the glomeruli are involved

Hospitalized neonates are at greatest risk of developing septicemia related to which procedure?

Catheter-associated bacteriuria Explanation: Catheter-associated bacteriuria remains the most frequent cause of Gram-negative septicemia in hospitalized neonates. The other procedures can cause bacteremia but are not the primary cause for this.

Horseshoe Kidney

Congenital malformation in which both kidneys are joined together by an isthmus, most commonly at the lower poles - May work normally - Usually not known until x-rays /exams are performed.

The amount of __________ present in a blood sample is the most reliable indicator of glomerular filtration rate.

Creatinine

Bowman's capsule

Cup-shaped structure of the nephron that surrounds the glomerulus (where filtration takes place).

Intra-Renal Acute Kidney Injury: Acute Tubular Injury or Necrosis

Destruction of tubular epithelial cells with acute suppression of renal function. Caused by acute tubular damage due to: - ischemia - sepsis - nephrotoxic effects of drugs - tubular obstruction - toxins from a massive infection. • tubular epithelial cells are sensitive to ischemia & vulnerable to toxins. - tubular injury is frequently reversible. - as sickle cell disease & mechanical trauma from artificial heart valves. In contrast to pre-renal AKI, the GFR does not improve with the restoration of renal blood flow in AKI caused by ischemic Acute Tubular Necrosis or Acute Tubular Injury.

A client is beginning to recover from acute tubular necrosis. During which phase of acute kidney injury will the nurse assess an increase in urine output?

Diuretic phase Explanation: The onset phase lasts hours/days and is the time from the onset of the precipitating event until tubular injury occurs. The oliguric phase is characterized by a marked decrease in glomerular filtration rate, causing sudden retention of endogenous metabolites, such as urea, potassium, sulfate, and creatinine. The diuretic phase occurs when the kidneys try to heal and one will see an increase/excessive output (diuresis) of dilute urine. The recovery phase is the period during which tubular edema resolves and renal function improves. There is normalization of fluid and electrolyte balance.

Several urine tests can be useful in establishing a diagnosis of acute renal failure (ARF). The nurse must consider that fractional excretion of sodium can be particularly affected by administration of which type of drug?

Diuretics Explanation: Diuretics, which directly affect renal excretion of sodium, can alter the fractional excretion of sodium. The other drug types listed do not affect this parameter of renal function.

An older adult with urge incontinence & overactive bladder begins medication treatment with oxybutynin. Which side effects would the nurse include in the education?

Dry mouth and constipation are common. Explanation: Anticholinergic effects of the muscarinic blocking agent oxybutynin include dry mouth and constipation. People taking anticholinergic drugs may also experience gastroesophageal reflux, blurred vision, urinary retention, & cognitive effects. Spasms are not common.

What is the most common cause of a lower urinary tract infection?

Escherichia coli Explanation: Most uncomplicated lower UTIs are caused by Escherichia coli. The other organisms can cause UTIs, but are not the most common cause of infection.

When the urinary system fails to function properly, what organ systems are affected?

Eventually all organ systems are affected.

The nurse is caring for a client with a condition of deficiency of antidiuretic hormone (ADH). When assessing the client, which finding does the nurse anticipate?

Excessive urine output Explanation: ADH regulates the ability of the kidneys to concentrate urine. When ADH is present, the water that moved from the blood into the urine filtrate in the glomeruli is returned to the circulatory system, and when ADH is absent, the water is excreted in the urine. Pathologically, deficiency of ADH leads to polyuria and dehydration.

Normal urine contains metabolic wastes, plasma proteins, & glucose molecules.

FALSE

The majority of reabsorption occurs in the efferent arteriole.

FALSE

Nephrons

Filtering units of the kidney that remove metabolic wastes from the blood & produce urine

Urine specific gravity is normally 1.010 to 1.025 with adequate hydration. When there is loss of renal concentrating ability due to impaired renal function, low concentration levels are exhibited. When would the nurse consider the low levels of concentration to be significant? a) After a nap b) Last void at night c) First void in morning d) At noon

First void in morning - With diminished renal function, there is a loss of renal concentrating ability, & the urine specific gravity may fall to levels of 1.006 to 1.010, usual range is 1.010 to 1.025 with normal fluid intake. These low levels are particularly significant if they occur during periods that follow a decrease in water intake.

When caring for the client with proteinuria, the nurse recognizes that dysfunction in which structure of the kidney allows protein to leak into the urine?

Glomerulus Explanation: Alterations in the structure & function of the glomerular basement membrane are responsible for the leakage of proteins & blood cells into the filtrate that occurs in many forms of glomerular disease.

A client informs the nurse that she is afraid of developing bladder cancer because her mother had it. She asks the nurse what signs and symptoms are present with this cancer. What does the nurse tell the client is the most common sign of bladder cancer?

Gross hematuria

What is the most common sign of bladder cancer?

Painless hematuria Explanation: The most common sign of bladder cancer is intermittent painless hematuria. Oliguria and proteinuria and hyperphosphaturia are associated with renal failure.

Describe the inheritance, pathology, and manifestations of the different types of polycystic kidney disease

Polycystic kidney disease (PKD) is an inherited disorder - clusters of cysts develop in kidneys, enlarging them - kidneys lose function over time. - cysts are noncancerous round sacs containing fluid. - cysts vary in size & grow very large. - multiple cysts & large cysts can damage the kidneys. - cysts can develop in liver & elsewhere. - it can cause high BP & kidney failure. - PKD varies greatly in its severity, & some complications are preventable. - Lifestyle changes & treatments might help reduce damage to the kidneys. Polycystic kidney disease symptoms can include: - High blood pressure - Back or side pain - Blood in your urine - A feeling of fullness in your abdomen - Increased abdominal size due to enlarged kidneys - Headaches - Kidney stones - Kidney failure - Urinary tract or kidney infections

Agenesis: characteristic facial features

Potter syndrome: - Eyes widely separated - Nose beak-like - Ears low set - Epic folds - Chin is receding - Limb defects

The anemia that occurs with end-stage kidney disease is often caused by the kidneys themselves. What loss of function in the kidney results in anemia of end-stage kidney disease?

Produce erythropoietin

Define the terms agenesis, hypoplasia, & dysgenesis, & discuss them as they refer to the development of the kidney.

Renal agenesis: - complete absence of one (unilateral) or both (bilateral) kidneys Renal aplasia: - the kidney has failed to develop beyond its most primitive form. - In practice, renal agenesis & renal aplasia might be indistinguishable. Renal hypoplasia: - abnormality that a person is born with in which one or both kidneys are smaller than normal: hypoplastic, but with normal structure. - abnormally small kidneys, where the size is less than two standard deviations below the expected mean for the corresponding demographics - the morphology is normal. - disease severity depends on whether hypoplasia is unilateral of bilateral, & the degree of reduction in the number of nephrons. Renal tubular dysgenesis - a severe kidney disorder characterized by abnormal development of the kidneys before birth. - kidney structures called proximal tubules are absent or underdeveloped.

The nurse is analyzing the results of a client's urinalysis. Which finding requires the need for follow-up by the nurse because it is an abnormal result?

Specific gravity 1.034 Explanation: Normal findings are: Color: yellow amber; appearance: clear to slightly hazy; specific gravity: 1.005-1.025 with a normal fluid intake; pH: 4.5-8.0 - average person has a pH of about 5 to 6; volume: 600-2500 mL/24 hour - average volume is 1200 mL/24 hour; glucose: negative; ketones: negative; blood: negative; protein: negative; bilirubin: negative; urobilinogen: 0.5-4.0 mg/day; nitrate for bacteria: negative; leukocyte esterase: negative; casts negative: occasional hyaline casts; red blood cells: negative or rare; crystals: negative (none); white blood cells: negative or rare; epithelial cells: few; hyaline casts 0-1/lpf (low-power field).:

The glomerular filtration rate can be used as a measure of the efficiency of kidney function.

TRUE

The kidneys are responsible for the elimination of numerous drugs.

TRUE

The loop of Henle plays a key role in the production of concentrated or diluted urine. True of false

TRUE

Assessment of Glomerular Filtration Rate

The best measure of overall function of the kidney. - normal GFR, varies with age, sex, & body size, & is approx. 120 to 130 mL/min/1.73 mL/m2 for normal young healthy adults. • Albuminuria serves as a key marker of kidney damage . Urine normally contains small amounts of protein. - However, if the kidneys are damaged, protein can "leak" out of the kidneys into the urine. • In most cases, urine dipstick tests are acceptable for detecting albuminuria. If the urine dipstick test is positive (1+ or greater), albuminuria is usually confirmed by quantitative measurement. • Microalbuminuria, which is an early sign of diabetic kidney disease, refers to albumin excretion that is above the normal range, but below the range normally detected by tests of total protein excretion in the urine. - Urine dipstick test for albuminuria - Albumin to creatinine ratio • Ultrasonography is particularly useful for detecting a number of kidney disorders, i.e urinary tract obstructions, infections, stones, & polycystic kidney disease.

A client with significant burns on his lower body has developed sepsis on the third day following his accident. Which manifestation would the nurse anticipate for an ischemic acute tubular necrosis rather than prerenal failure?

The client's GFR does not increase after restoration of renal blood flow

The nurse is caring for a client who has produced an average of 20 mL/hour for the previous day. The nurse recognizes this compares in which way to the normal urine output?

The kidneys should produce about 1.5 L of urine each day.

A nursing student studying pharmacology is learning how angiotensin converting enzyme inhibitors (ACE) work. The student is correct when stating that the mechanism of action of ACE inhibitors is to:

prevent conversion of angiotensin I to II. Explanation: The juxtaglomerular cells of the kidney contain granules of inactive renin, an enzyme that functions in the conversion of angiotensinogen to angiotensin. Angiotensin I is converted to angiotensin II in the presence of converting enzyme. By blocking converting enzyme, angiotensin II, a potent vasoconstrictor, is not produced, thus lowering blood pressure.

The nurse recognizes the most common cause of acute post-infectious glomerulonephritis as:

streptococcal infection 7 to 12 days prior to onset. Explanation: Acute post-infectious glomerulonephritis usually occurs after infection with certain strains of group A beta-hemolytic streptococci & is caused by deposition of immune complexes. It also may occur after infections by other organisms, including staphylococci & a number of viral agents, such as those responsible for mumps, measles, & chickenpox.

•Chronic Kidney Disease in Older Adults

• Aging is associated with: - steady decline in kidney function - decreasing GFR, &, subsequently - reduced homeostatic regulation under stress. • Reduction in GFR makes older adults susceptible to the effects of nephrotoxic drugs, such as radiographic contrast compounds.

Most common abnormality in congenital kidney disorders

- Abnormalities in shape & position of kidneys

The fetal urine is excreted inside of the ___________________

- Amniotic cavity - It's excreted in the amniotic fluid - Amniotic fluid test: done to assess fetus renal function - Little amniotic fluid means the kidneys are not functioning well - Fetus kidneys start working at 13 weeks of gestation

Neurogenic bladder is bladder dysfunction (flaccid or spastic)

- Caused by neurologic damage. - Symptoms can include overflow incontinence, frequency, urgency, urge incontinence, & retention. - Risk of serious complications, eg, recurrent infection, vesicoureteral reflux, & autonomic dysreflexia is high.

Renal dysplasia

- Congenital kidney disorder - caused by abnormality in differentiation of kidney structures during embryonic development - abnormal development of one or both kidneys; presents as an enlarged, irregular, cystic flank mass - if bilateral, may lead to renal failure

Agenesis

- Congenital kidney disorder 1) Bilateral renal agenesis - kidney fails to develop 2) Unilateral renal agenesis: - affects more boys than girls - compensatory hypertrophy: performs the function of the missing kidney

Treatment of Hyperphosphatemia & Hypocalcemia (renal skeletal complications)

- Important to prevent skeletal complications - Restriction of dairy & foods high in phosphorus

Renal Hypoplasia

- Incomplete development of the kidney to normal size, usually with fewer than five calyces/lobes - Like agenesis, it usually affects one kidney - If both kidneys are affected, renal failure progresses - Cause is unknown, often an incidental finding - Small kidneys may result from atrophy & scarring

When do the kidneys begin to develop?

- Kidneys begin to develop early & begin producing urine by week 13 of gestation.

Multi-cystic kidney dysplasia

- Mass of cysts, abnormally shaped. - Usually unilateral - Excellent prognosis: remove the affected kidney

Post-renal Acute Kidney Injury

- Obstruction of urine outflow from the kidneys. - pressure in tubules damages the nephrons Occurs in: - ureter: i.e., calculi - urethra: i.e., prostatic hyperplasia. - stricture bladder: i.e., tumors or neurogenic bladder - increased urine can't be excreted due to obstruction - retrograde pressure occurs throughout the tubules & nephrons, damaging the nephrons. The course of AKI can be divided into four phases: 1) • Onset phase: - lasts hours or days - time of onset of event: - e.g., ischemic phase of pre-renal failure or toxin - exposure until tubular injury occurs. 2) • Oliguric (anuric) phase: - lasts 8 to 14 days or longer depending on the nature of AKI. - characterized by marked decrease in GFR, causing sudden retention of endogenous metabolites; urea, potassium, sulfate, & creatinine, which are normally cleared by the kidneys. The urine output is usually lowest at this point. Fluid retention gives rise to edema, water intoxication, & pulmonary congestion. If the period of oliguria is prolonged, hypertension frequently develops & with it signs of uremia. When untreated, the neurologic manifestations of uremia progress from neuromuscular irritability to seizures, somnolence, coma, & death. Hyperkalemia is usually asymptomatic until the serum potassium level rises above 6 to 6.5 mEq/L, at which point characteristic electrocardiographic changes & symptoms of muscle weakness are seen. 3) • Diuretic phase: when the kidneys try to heal & urine output increases, but tubule scarring & damage occur. Diuresis often occurs before renal function has fully returned to normal. Consequently, the BUN, serum creatinine, potassium, & phosphate levels remain elevated or continue to rise, even though urine output is increased. During this phase, the GFR increases, urine output increases to 400 mL/day, & electrolytes are possibly depleted from excretion of more water & osmotic effects of a high BUN. 4) • Recovery phase: the period during which tubular edema resolves & renal function improves. During this phase, there is normalization of fluid & electrolyte balance. Eventually, renal tubular function is restored with improvement in concentrating ability. At about the same time, the BUN & creatinine begin to return to normal, & the GFR returns to 70% to 80% normal. In some cases, mild-to-moderate kidney damage persists .• Diagnosis and Treatment: - Careful observation of urine output - Find out if there's an obstruction - Given the high morbidity & mortality rates associated with AKI, attention should be focused on prevention & early diagnosis: - assessment to identify people at risk for development of AKI, including those with pre-existing renal insufficiency & diabetes. - They are at risk for AKI due to nephrotoxic drugs or NSAIDs that alter intra-renal hemodynamics. - Older adults are susceptible to all forms of acute renal failure because of the effects of aging on renal reserve. • Careful observation of urine output is essential for people at risk for development of acute AKI. - Urine tests that measure urine osmolality, urinary sodium concentration, & fractional excretion of sodium help differentiate pre-renal azotemia (reduced blood flow to the kidney), in which the reabsorptive capacity of the tubular cells is maintained, from tubular necrosis, in which these functions are lost. One of the earliest manifestations of tubular damage is the inability to concentrate the urine.

Cystic Dysplasia

- One or both kidneys can be involved - The affected kidney may be abnormally small or large

Ectopic Kidneys

- One or both kidneys may be in an abnormal position - Most located in the pelvic, but some lie in the inferior part of the abdomen - pelvic kidneys and other forms of ectopic result from failure of the kidneys to "ascend"

Hypertension frequently accompanies chronic kidney disease (CKD). The nurse knows that which of the following mechanisms can contribute to this hypertension? Select all that apply.

- Renin-angiotension aldosterone (RAAS) activation - Sodium retention - Increased vasoconstriction - Increased blood volume.

Chronic Kidney Disease (CKD)

- progressive decline in kidney function because of the permanent loss of nephrons. - worldwide problem - affects people of all ages, races, & economic groups. • prevalence & incidence of the disease, mirroring conditions like diabetes, hypertension, & obesity, are rising. • Guidelines use the GFR to classify CKD into five stages, beginning with kidney damage with normal or elevated GFR, progressing to CKD &, potentially, to kidney failure. • It is anticipated that early detection of kidney damage along with implementation of aggressive measures to decrease its progression can delay or prevent the onset of kidney failure. • CKD can result from a number of conditions, including diabetes, hypertension, glomerulonephritis, and other kidney diseases. • The GFR is considered the best measure of kidney function.

Acute Kidney Injury

- rapid decline in kidney function that happens within a few hours or within a day. • causes buildup of nitrogenous waste products & impairs fluid & electrolyte balance, is potentially reversible if the precipitating factors can be corrected or removed before permanent kidney damage has occurred. • common threat to seriously ill people in intensive care units& increases mortality rate (kills 50 to 60% of them) • most common indicator of AKI is azotemia: accumulation of nitrogenous wastes: urea nitrogen, uric acid, & creatinine in the blood & a decrease in the glomerular filtration rate (GFR). - can be induced by medications, cariogenic shock • As a result, excretion of nitrogenous wastes is reduced, & fluid & electrolyte balance cannot be maintained.

Intra-renal Acute Kidney Injury

- results from conditions that cause damage to structures within the kidney. • Most frequent causes: 1) damage to the parenchyma in the glomeruli, vessels, tubules, or interstitium. 2) ischemia associated with prerenal AKI 3) toxic insult to the tubular structures of the nephron 4) intra-tubular obstruction.

Kidney location

- retroperitoneal - right kidney lower to accommodate liver

Oligohydramnios

- small amniotic fluid - congenital disorder - non-functional kidneys in fetus - outflow obstruction

Personal habits regarding urination are affected by:

- social politeness of leaving to urinate - the availability of a private clean facility bladder training. - bladder training

Hydronephrosis

- urine filled dilation of renal pelvis & calices - progressive kidney atrophy due to urine outflow obstruction. • duration, degree, & level of obstruction • mostly unilateral - bilateral hydro-nephrosis occurs only when the obstruction is below the level of the uretero-vesical junction (progressive) • the obstruction affects outflow of urine from distal ureter & increased pressure dilates ureter: - hydro-ureter. - may remain silent - obstruction may provoke pain d/t distension of collecting system & renal capsule. • Complete bilateral obstruction results in: - oliguria: decreased urine flow - progressing to anuria - renal failure. • Partial obstruction results in: - inability to concentrate urine - polyuria - nocturia. • Diagnosis: - Ultrasound is the single most useful noninvasive diagnostic modality. - CT & IVP (intravenous urography), U/A • Treatment: - depends on cause. - stone removal - surgery - antibiotics

Urinary Tract Infections

- Second most common cause of infection, after pneumonia, in older adults. - 11% of infections among healthy adults - 50% older adults in long-term care facilities • Mostly caused by bacteria entering the urethra. - Most: acute uncomplicated bladder infections in women. - People with diabetes are susceptible to upper urinary tract infections. - Children: less symptoms - Washout phenomenon: urine from bladder washes bacteria out of the urethra. - asymptomatic bacteriuria - symptomatic infections - lower UTIs such as cystitis - upper UTIs such as pyelonephritis. - Upper UTIs are more serious than lower UTIs: causes renal damage - Uncomplicated lower UTIs caused by E. coli - Complicated UTIs caused by: - Klebsiella pneumoniae - Enterococcus faecalis - Enterobacter spp. - Proteus mirabilis - Pseudomonas aeruginosa. • Increased risk for UTIs: - urinary obstruction - reflux - neurogenic disorders that impair bladder emptying - women who are sexually active - post-menopausal women - diseases of the prostate - older adults. Instrumentation & urinary catheterization: CAUTI: Catheter Acquired UTI. most common factors for nosocomial UTIs. - Bacterial will form a biofilm - Colonization may appear asymptotic. - UTI manifestations vary if the infection involves the lower (bladder) or upper (kidney) urinary tract & whether the infection is acute or chronic. - Upper UTIs: affect kidney parenchyma & pelvis pyelonephritis. - Acute Pyelonephritis: kidney parenchyma & pelvis (dangerous) - They are less common & occur mostly in children & adults with urinary tract obstructions. • An acute episode of cystitis (bladder infection) is characterized by frequency of urination, lower abdominal or back discomfort, & burning & pain on urination (i.e., dysuria). Occasionally, the urine is cloudy & foul smelling. Pyuria Leukocytes (5 to 8) Gram stain Urine Culture • Diagnosis: - urine tests, x-ray, ultrasonography, CT & renal scans • Treatment: - based on the pathogen causing the infection - Only bacteria able to adhere to the epithelium cells will be able to produce an infection

The nursing instructor who is teaching about incontinence in older adults recognizes a need for further instruction when a student makes which statement?

"Frequency is not a major problem for the elderly." Explanation: Incontinence can increase social isolation in the older adult population & frequency can lead to institutionalization of older adults. Many factors can contribute to incontinence but many of these can be altered.

A student presents to the campus clinic with reports of frequent, burning urination & is diagnosed with an acute lower urinary tract infection (UTI) caused by Escherichia coli. What teaching will the health care provider most likely provide to the student?

"Many of these bacteria are now resistant to some antibiotics, but I will take that into account when I choose which antibiotic to prescribe." Explanation: Microbial resistance to antibiotics is now common but other specific antibiotic options exist. Cranberry & blueberry juice are more appropriate as preventive rather than curative measures, reducing bacterial adherence to the epithelial lining of the urinary tract, & the majority of uncomplicated UTIs in young adults are NOT the result of urinary obstructions.

A client in the hospital is frustrated at the inconvenience of having to collect his urine for an entire day and night as part of an ordered 24-hour urine-collection test. The client asks the nurse why the test is necessary since the client provided a single urine sample 2 days prior. How could the nurse best respond?

"Often when an abnormal substance shows up in a urine test, a 24-hour urine collection is needed to determine exactly how much is present in your urine."

Inherited Cystic Kidney Disease:

- Single cell gene disorders transmitted through Mendelian Patterns - Origin in the kidney tubules Polycystic kidney diseases: - kidney disorders with fluid-filled sacs or segments - tubular structures • Cysts: single or multiple

2) Autosomal recessive polycystic kidney disease (ARPKD)

- Small elongated cysts form in collecting ducts & maintain with the nephron - Caused by a gene mutation. - Cystic dilation of the cortical & medullary collecting tubules. - Infants: bilateral flank masses, severe renal failure. - Enlarged kidneys restrict lung development & function - Liver fibrosis & portal HTN - Potter fascis - Death is common in peri-natal period due to pulmonary hyperplasia • Treatment: - largely supportive - aggressive ventilatory support is often necessary

A person's urinary system depends on their________

- Social habits - Personal habits - Own physical abilities

1) Autosomal dominant polycystic kidney disease (ADPKD)

- Thousands of large cysts are derived from every segment of the nephron - Single cell gene disorder transmitted via Mendelian Patterns - Origin in the kidney tubules - Most common hereditary form of renal cystic disease - Destructive fluid-filled cysts in kidney & other organs - 4th leading cause of end-stage renal disease in the U.S. (5% of all cases of chronic kidney disease the requires dialysis). - Pathogenesis is unclear: abnormal epithelium allows for cysts formation. - High proliferation rate, relatively undifferentiated - Defective basement membrane - Slow progression, early asymptomatic with normal kidney & liver function - As cysts enlarge: pain, gross hematuria, infection, hypertension: from compression of intra-renal blood vessels with activate the RAAS mechanism. - Late stage progression: aneurysms are common Diagnosis: - Total kidney volume (TKV) in relation to age is a reliable predictor of increasing cyst burden. - Ultrasound & CT Treatment: - largely supportive & lifestyle modifications - dialysis & kidney transplant reserved for those who progress to kidney failure

Chronic Kidney Disease Clinical Manifestations

- accumulation of nitrogenous wastes: urea (uremia) is the first one, then BUN. normal is 20mg/dl Coma and death can follow after the accumulation of nitrogenous wastes if nothing is done. - vitamin d impairment - alterations in water, electrolyte, & acid-base balance kidneys function in regulating ECF volume by eliminating or conserving fluid volume. one of the earliest symptoms of kidney damage is polyuria. specific gravity: 1.008 to 1.082 - 90% of potassium excretion is through the kidneys = hyperkalemia - when kidney function is severely compromised Metabolic acidosis may occur which stabilizes as the disease progresses due to buffer mechanisms. - mineral & skeletal disorders: phosphate goes up and calcium falls drop in serum calcium stimulates the parathyroid hormone most people with CDK have secondary hypoparathyroidism because of the down regulation of the parathyroid receptors of the parathyroid gland. Both Vit D and Calcium are down regulated causing an elevation in the PTH and decrease in Calcium and Vit D levels. Renal Osteodystrophy aka Chronic Kidney Disease Mineral Bone disorder: CDK-MBD: skeletal complications of CKD. 2 Types: 1) High Bone Turnover 2) Low Bone Turnover - anemia & coagulation disorders (coagulopathy) Anemia: Hemoglobin less than 13 g/dl men, 12g/dl women Kidneys make & Erythropoietin control RBC production, making of RBC in body Anemia = decrease in blood viscocity & vascular resistance. Heart needs to increase workload to avoid tissue perfusion. Angina pectoris is an ischemic event Maintain iron level, give erythropoietin stimulating agent. - Eating disorders - Hypertension - alterations in cardiovascular function/ heart disease 10 to 20 times higher in people with CKD than general population. Increase vascular volume, decrease renal prostaglandins, RAAS increas, left ventricular hypertrophy - less efficient. CHF, edema PERICARDITIS: - Late state of CDK because of UREMIA & prolonged dialysis - infection of the pericardium that surrounds the heart. Gastrointestinal disorders: anorexia, nausea & vomiting bitter metallic taste, ulcerations, bleeding. Neurologic complications: Peripheral - sensory & motor disfunction caused by atrophy, & uremia-toxins, restless leg syndrome, burning sensation of feet. Central: Uremic encephalopathy: attention, memory loss, errors identifying people or objects, seizures are pre-terminal events, unsteady gait, clumsy (asterisis) dorse-flexion. Excess of toxic organic acids • neuromuscular disorders Disorders of skin integrity Often pale due to anemia Xerosis: Bruising Pruritus: itching of skin due to high phosphate/occur with hyperparathyroid. Disorders of immunologic function. Vascular access devices cause these issues Fever • calcium & Phosphorus Metabolism Disorders • bone Disease • pericarditis • Sexual Dysfunction loss of libido decrease of hormones • Elimination of Drugs CKD can interfere with the absorption, distribution, & elimination of the drug. Decrease in plasma proteins (albumin) results in less protein binding sites for the drugs to attach to which causes greater amounts of free drug in the systemic circulation: drug toxicity.

Obstructive Disorders of the Kidney (Obstructive Neuropathy)

- any age & level of the urinary tract. - suddenly or insidiously, partial or complete - unilaterally or bilaterally • classified by site, degree, & duration of obstruction. • destructive effects determined by degree & duration of obstruction. - Can result in atrophy & of bilaterally it results in chronic renal failure Damaging effects: • 1. Stasis of urine - predisposes to infection & stone formation • 2. Progressive dilation of renal collecting ducts & renal tubular structures • Hydro-nephrosis • Renal Calculi The GFR will eventually diminish from the pressure in the tubules and built up of urine from the obstruction.

Lower urinary tract

- bladder - urethra - pelvic floor

Kidneys are the primary regulators of_________

- fluids & acid base balance

What does urinary elimination depends on?

- kidneys - ureters - bladder - urethra

Upper urinary tract

- kidneys - ureters.

Renal Failure

- kidneys fail to remove metabolic end products from the blood & regulate the fluid, electrolyte, & unable to maintain pH balance of the extracellular fluids. • The underlying cause may be renal disease, systemic disease, or urologic defects of nonrenal origin. • Renal failure can occur as an acute or a chronic disorder. • Acute kidney injury has an abrupt onset and is often reversible if recognized early and treated appropriately. • Chronic kidney disease (CKD) is the end result of irreparable damage to the kidneys. • Develops slowly, over the course of a number of years. • 80% of the nephrons need to be nonfunctioning before the symptoms of CKD are manifested.

Acquired Renal Cysts

- occurs in people with ESRF after prolonged dialysis treatment • largely asymptomatic • hematuria

The basic functional units of the kidneys are the __________.

nephrons

Inherited Cystic Kidney Disease types:

1) Autosomal dominant polycystic kidney disease (ADPKD) - Thousands of large cysts are derived from every segment of the nephron 2) Autosomal recessive polycystic kidney disease (ARPKD) - Small elongated cysts form in collecting ducts & maintain with the nephron 3) Nephronophthisis medullary cystic disease (NPHP) • Simple cysts develop in the kidney as a consequence of aging, dialysis

Chronic Kidney Disease Definition

1) either kidney damage or 2) GFR less than 60mL/min/1.73m2 for 3 months or longer. • can result from conditions that cause permanent loss of nephrons. •Hypertension & diabetic kidney disease are two main causes of CKD in the United States. The NKF practice guidelines define kidney failure as either: 1) A GFR of less than 15 mL/min/1.73 m2, usually accompanied by most of the signs & symptoms of uremia, or 2) A need to start renal replacement therapy: dialysis or transplantation

What's the primary function of the kidneys?

1) filter & remove waste products of metabolism from the blood 2) form urine

The kidneys regulate the body's __________ by conserving bicarbonate & eliminating hydrogen ions.

pH

Which assessment indicates to the nurse that a client may have a spastic bladder dysfunction?

Incontinence

A client is to receive a radiocontrast media as part of a diagnostic scan. Which intervention is intended to reduce the nephrotoxic effects of the radiocontrast media?

Increasing the normal saline intravenous infusion rate prior to the exam Explanation: Some drugs such as high-molecular-weight radiocontrast media, the immunosuppressive drugs cyclosporine and tacrolimus, and nonsteroidal anti-inflammatory drugs can cause acute prerenal failure by decreasing renal blood flow. Administering intravenous saline can improve hydration and renal perfusion to decrease the toxic effects of the radiocontrast media.

What is the usual cause of acute pyelonephritis?

Infection Explanation: Gram-negative bacteria, including Escherichia coli & Proteus, Klebsiella, Enterobacter, & Pseudomonas species, are the most common causative agents for acute pyelonephritis.

Diabetes, hypertension & systemic lupus can contribute to____________

Kidney disease

Pre-renal Acute Kidney Injury

The most common form of AKI, characterized by a marked decrease in renal blood flow. • It is reversible if the cause of the decreased renal blood flow can be identified & corrected before kidney damage occurs. - Ischemia is pre-renal but can progress into intra-renal if not treated. • Causes: • depletion of vascular volume:e.g., hemorrhage, loss of extracellular fluid volume • impaired perfusion because of heart failure • cardiogenic shock • decreased vascular filling because of increased vascular capacity: e.g., anaphylaxis or sepsis • Some vasoactive mediators, drugs, & diagnostic agents stimulate intense intra-renal vasoconstriction & can induce glomerular hypoperfusion & prerenal AKI. Examples radiocontrast agents such as those used for cardiac catheterization, & nonsteroidal anti-inflammatory drugs (NSAIDs). These drugs cause acute tubular necrosis (ATN; discussed later). • Normally, the kidneys receive 20% to 25% of the cardiac output. If below this, ischemic changes will occur. - large blood supply is required for the glomeruli to remove metabolic wastes & regulate body fluids & electrolytes. • Fortunately, the normal kidney can tolerate relatively large reductions in blood flow before renal damage occurs. As renal blood flow is reduced, the GFR decreases. • As the GFR & urine output approach zero, oxygen consumption by the kidney approximates that required to keep renal tubular cells alive. • Improperly treated, prolonged renal hypoperfusion can lead to ischemic tubular necrosis with significant morbidity & mortality. • An early sign of prerenal AKI is a sharp decrease in urine output. - BUN is small and can be reabsorbed but creatinine is a larger particle and it will show as much higher on lab results compared to BUN. - Before going for cat scan, MUST assess BUN, creatinine, GFR

Which client is likely at the greatest risk of developing a urinary tract infection?

You Selected: A client with a diagnosis of chronic kidney disease who requires regular hemodialysis Correct response: A 79-year-old client with an indwelling catheter Explanation: Indwelling catheters are strongly associated with the development of UTIs, and this risk factor supersedes pregnancy and kidney disease. Frequency and incontinence may be signs and symptoms of UTIs, but they are not causative of the infections.

Kidneys consist of an outer cortex and an inner __________.

medulla

__________ are drugs that increase the volume of urine.

diuretics

Renal Calculi (kidney stones)

• Most common cause of upper tract obstruction. • Polycrystalline aggregates materials that kidneys normally excrete in urine. • Several factors contribute to stone formation: - supersaturated urine. (depends on pH, ions, etc) - presence of a nucleus for crystal formation - NIDUS - deficiency of inhibitors of stone formation. 1) Calcium stones: most common; increased concentrations in the blood & urine from oxalate & phosphates: 75% to 85%. Immobility. Renal Tubular acidosis. High oxalate in the blood. (pseudomonas/e-coli) 2) Uric acid stones: increased BMI & low urine pH. - not visible on x-ray films, form most readily in acidic urine, treated by raising the urinary pH from 6 to 6.5 with potassium alkali salts. - gout & high concentrations of uric acid in the urine 3) Magnesium ammonium phosphate stones: aka struvite stones form only in alkaline urine (pH > 7.0) & in the presence of bacteria that possess an enzyme called urease, which splits the urea in the urine into ammonia & carbon dioxide. Because of their shape, they often are called staghorn stones. Struvite stones usually are too large to be passed & require lithotripsy or surgical removal. 4) Cystine stones: significant proportion of childhood calculi. cistinuria (autosomal genetic defects) account for about 7% of all stones • Clinical Manifestations: - pain: renal colic & non-colicky renal pain • Renal colic: colicky pain, stretching of collecting system or ureter. • Non-colicky pain: caused by stones producing distention of renal calyces or pelvis • Diagnosis: - U/A, plain radiograph, IVP (intra-venous paleography), U/S - U/A can tell the pH of urine • Treatment: - largely supportive - pain relief - ABX - uteteroscopic removal - percutaneous removal extracorporeal lithotripsy - open stone surgery.

Amniotic Fluid Kidney Disorder

• Renal Hypoplasia: - underdeveloped kidneys that contain less lobules • Unilaterally: - more frequent • Bilaterally: - renal failure progressively develops • Renal Dysplasia: - caused by an abnormality in the differentiation of kidney structures during embryonic development. • Cystic dysplasia - Alterations in Kidney Position & Form

3) Nephronophthisis medullary cystic disease (NPHP)

• Simple cysts develop in the kidney as a consequence of aging, dialysis - Complex group of renal disorders - begin in childhood - small, shrunken kidneys cysts in corticomedullary junction. - Distal tubules, tubular basement membrane destruction, progressing to chronic tubular atrophy involving medullar and cortex. - Polyuria, polydipsia, enuresis: wetting bed, impaired ability to concentrate urine, salt wasting, growth retardation, anemia, progressive renal insufficiency. • Extra-renal complications: - skeletal defects - ocular motor abnormalities (retinitis picmentosa) - liver fibrosis - cardiac septal & valve defects - cerebellar abnormalities.

What is the severity of kidney conditions?

• Some conditions are acute & reversible • Others are chronic & irreversible: slow, progressive development of renal dysfunction.

Chronic Kidney Disease in Children

• The causes of CKD in children include: - congenital malformations - inherited disorders - acquired diseases - metabolic syndromes. • In children, congenital anomalies of the kidney & urinary tract are most common, followed by the hereditary nephropathies & glomerulonephritis.

Types of Acute Kidney Injury

• caused by: - decrease in blood flow without ischemic injury - ischemic - toxic - obstructive tubular injury - obstruction of urinary tract outflow. • The causes of AKI are commonly categorized as prerenal, intrarenal, and postrenal. • Prerenal & Intrarenal causes 80% to 95% of cases.

Simple Renal Cysts: Benign

• common disorder of the kidney • can be single or multiple; unilateral or bilateral. • Usually < 1 cm • Usually asymptomatic If symptomatic: - flank pain - hematuria - infection - HTN related to ischemia caused by RAAS • Do not affect renal function • Most common in adults

Chronic Kidney Disease Treatment

• treated by conservative management to prevent or slow the rate of nephron destruction - when necessary, by renal replacement therapy with dialysis or transplantation. •Treatment Types: • Measures to Slow Progression of the Disorder (conservative treatment) • Dialysis & Transplantation • 1) Hemodialysis: artificial kidney in a machine. blood delivery system, dialyzer (capillary tubules, high to low concentration/ all molecules except for plasma proteins and blood cells) and bicarbonate can be added. Fluid moves both ways/ osmosis • 2) Peritoneal Dialysis: osmosis/surgically implant catheter thin membrane of the peritoneal cavity below the umbilicus for access. It's tunneled inside of abdomen. Pouring 1 to 3 liters of dialyzing solution through he catheter for 10 minutes. It stays for a few hours in the peritoneal cavity. At the end of the dwell time, the fluid will be drained out of the peritoneal cavity into a sterile bad. • Transplantation: depends of the health of the person receiving it, the compatibility of organ, medication management. • Dietary Management: - Protein: restrictions - Carbs & fats are needed - Fluids and electrolytes are very important - Sodium is individualized depending on patient - Unappetizing - Ice chips while in hemodialysis - Some patients can only get 500 to 800 ml of fluids daily, no more.