Interferences
with
Urinary Elimination
Urinary Elimination
“Bones can break, muscles can
atrophy, glands can loaf, even the
brain can go to sleep without
immediate danger to survival. But
should the kidneys fail….neither
bone, muscle, gland, nor brain could
carry on.”
Urinary System
Kidneys
Macrostructure
Paired, reddish, brown bean-shaped organs
Location:
Retroperitoneal on either side of the vertebral
column
12th thoracic vertebrae to 3rd Lumbar
Left kidney is 1.5 to 2 cm higher than right
Weight: 115 – 175 gms (4-6 ounces)
Adrenal Gland lies on top of each kidney
Kidneys
Microstructure
Nephron -- Functional unit of kidney, forms
urine
Each kidney has 1 million nephrons
Each Nephron is composed of:
Cortex: glomerulus, Bowman’s capsule,
proximal convoluted tubule, distal convoluted
tubule
Medulla: The loop of Henle and collecting ducts
Kidneys
Microstructure
Glomerulus – selective filtration
Bowman’s Capsule – semipermeable membrane /
hydrostatic pressure changes
Proximal tubule: Active transport
Reabsorption of 80% of electrolytes & water
Reabsorption of all glucose & amino acids
Reabsorption of HCO3- Acid-Base Balance
Reabsorption of Creatinine
Loop of Henle:
Reabsorption of Na+ & Cl- in ascending limb
Reabsorption of water in descending loop
Concentration of filtrate
Kidneys
Microstructure
Distal Tubule:
Secretion of K+, H+, ammonia
Reabsorption of water (regulated by ADH)
Reabsorption of HCO3- -- Acid-Base Balance
Regulation of Ca++ and PO4- by parathyroid
hormone
Regulation of NA+ & K+ by aldosterone
Collecting Duct:
Reabsorption of water (ADH required)
Blood Supply
Blood reaches kidney via renal artery
20-25% of cardiac output
1200 ml per minute
TO KIDNEY: Aorta – renal artery – kidney
hilus
Renal artery divides into secondary branches,
then into smaller braches to afferent arteriole
Capillary network – Glomerulus
FROM KIDNEY: Efferent arteriole –
Peritubular capillaries – Renal vein – inferior
vena cava
Nephron Function
Physiology of Urine
Formation
Normal glomerular function- Urine formation
starts at glomerulus where blood is filtered
GFR-(Glomerular filtration rate)- amt of blood
filtered by glomeruli in a given time
Normal GFR- 125ml/minute, however only 1 ml
per minute becomes urine, most is reabsorbed
Nephron Function
Renal Function
Other Kidney Functions
Hormone Production
Erythropoietin
In response to hypoxia & decreased renal blood flow
Stimulates RBC production in the bone marrow
Deficiencies lead to anemia in renal failure
Renin
Released from juxtaglomerular apparatus of the nephron
In response to < arterial BP, renal ischemia, > NA+
concentration
Splits angiotensinogen into angiotensin I = angiotensin II
Stimulates aldosterone from the adrenal cortex = water +
NA+ retention + peripheral vasoconstriction
Renin-angiotensinaldosterone System
Other Kidney Functions
Hormone Production
Prostaglandins (PGs)
Kidney medulla
Vasodilating action = increases renal blood flow
and promotes NA+ excretion
Counteracts the vasoconstrictor effect of
angiotensin and norepinephrine
Lowers arterial BP by decreasing systemic vascular
resistance
Active metabolite of Vitamin D – second step
in activating Vitamin D after action of ultraviolet
radiation on cholesterol in the skin
Nursing Process
Alterations in Urinary
Function
Assessment: Patient history
Physical Assessment:
inspection, percussion, palpation
Assessment of Urine: color, clarity, odor
Urine testing & specimen collection
Urinalysis, C&S, Composite urine collection
Creatinine Clearance – 85-135ml/min
Diagnostic tests: KUB (kidney, ureter, bladder)
renal ultrasound, renal CT scan
Invasive: IVP, Cystoscopy, arteriogram,
urodymanics
Upper
Urinary Tract Infections
Acute Pyelonephritis
Chronic Pyelonephritis
Acute Glomerulonephritis
Acute Poststreptococcal
Glomerulonephritis
Chronic Glomerulonephritis
Acute Pyelonephritis
Inflammation of the renal parenchyma and
collecting system
Most common cause: bacterial (E.coli,
Proteus, Klebsiella, Enterobacter species)
Pre-existing factor: vesicoureteral reflux
Commonly begins in the renal medulla and
spreads to the adjacent cortex
Recurring episodes may lead to chronic
pyelonephritis
Urosepsis: bacteriuria and bacteremia
Acute Pyelonephritis
Clinical Manifestations: sudden chills, fever,
vomiting, malaise, flank pain, and lower UTI
symptoms of cystitis
Diagnostics:
Urinalysis: pyruia, bacteriuia, hematuria
Imaging Studies: IVP, CT Scan, Ultrasonography
of the urinary system
Acute Pyelonephritis
Medical Management for Mild Symptoms:
Short hosp stay for IV antibiotic or OP oral antibiotics
Empiric broad spectrum (Ampicillin / Vancomycin)
combined with aminoglycoside
Change to sensitivity-guided therapy when culture results
are available for 14-21 days
Sulfa—Bactrim / Cipro / Floxin
Adequate fluid intake
Nonsteroidal antiinflammatory drugs
Antipyretic drugs
Urinary analgesics – Pyridium
Follow-up cultures & imaging studies
Relapse may occur – treated with 6-week course of antibiotics
Antibiotic prophylaxis
Acute Pyelonephritis
Medical Management for Severe Symptoms:
Hospitalization
Parenteral antibiotics
Broad-spectrum – switch to sensitivity specific
Followed by oral antibiotics 7-21 days
Adequate fluid intake – parenteral until symptoms
of N/V, dehydration subside
Relieve pain
Treat fever
Urinary antiseptics
Follow-up culture imaging studies
Chronic Pyelonephritis
Term used to describe a kidney that has
lost function due to scarring and fibrosis
Result of chronic upper urinary tract infections
Other names: interstitial nephritis, chronic
atrophic pyelonephritis, reflux nephropathy
Level of renal function depends on:
whether one or both kidneys are affected
magnitude of scarring
the presence of co-existing infection
Progresses to end-stage renal disease
when both kidneys are affected
Acute Glomerulonephritis
Immunologic process resulting in inflammation of
the glomeruli
Usually affects both kidneys equally
Tubular, interstitial, and vascular changes occur
Etiology:
Two types:
Antibodies have specificity for antigens within the glomerular
basement membrane (GBM) – produce autoantibodies – to one’s
own tissue -- mechanism unknown
Antibodies react with circulating nonglomerular antigens and are
randomly deposited as immune complexes along the GBM
End result: glomerular injury as a result of inflammation
Acute Glomerulonephritis
Clinical Manifestations:
Varying degrees of hematuria
Varying degrees of urinary excretion of WBC and casts
Proteinuria
Elevated BUN and Creatinine and Albumin
+ renal biopsy
Medical Management:
Rest
Sodium and fluid restriction
Diuretics
Antihypertensive therapy
Decreased dietary protein
Glomerulonephritis
Chronic Glomerulonephritis
Syndrome – end-stage glomerular inflammatory
disease
Proteinuria, hematuria, slow development of uremic
syndrome = decreased renal function
Slow course toward renal failure over a few to as
many as 30 years
Often found coincidentally with abnormal UA or
elevated blood pressure
Confirmed with ultrasound and CT scan – Renal Bx
Medical Management:
Treat HTN
Treat UTIs
Protein and Phosphate restriction
Acute Poststreptococcal
Glomerulonephritis
Most common in children & young adults
5-21 days after a streptococcal sore throat or
impetigo
Nephrotoxic strains of group A B-hemolytic
streptococci
Antibodies are produced to the strept antigen
Unknown mechanism – the antigen-antibody
complexes are deposited in the glomeruli –
leads to = decreased glomerular filtration &
inflammation
Acute Poststreptococcal
Glomerulonephritis
Clinical Manifestation:
Generalized body edema, hypertension, oliguria,
hematuria, oliguria, proteinuria, fluid retention,
edema in low-pressure tissues – periorbital edema
abdominal or flank pain
Patient may be asymptomatic – UA finding
Diagnostics:
Antistreptolysin O (ASO) titers
Renal biopsy
Erythroycte casts
Elevated BUN and Creatinine
Acute Poststreptococcal
Glomerulonephritis
Medical Management:
Rest until signs of glomerular inflammation subside
(proteinuria & hematuria)
Treat hypertension
Restrict sodium & fluid intake
Antibiotics only if streptococcal infection is still
present
Prevention: Early diagnosis & treatment of
sore throats and skin lesions; good personal
hygiene, patient adherence to antibiotic therapy
Renal Conditions
Polycystic Kidney
Renal Artery Stenosis
Renal Tuberculosis
HIV—associated Nephropathy
Nephrotic Syndrome
Polycystic Kidney
One of the most common genetic diseases
Two forms:
Childhood manifestation: rare autosomal
recessive disorder with rapid progression
Adult manifestation: autosomal dominant
disorder – latent – 30-40 years of age
Involves both kidneys
Cortex & medulla are filled with thin-walled
cysts that are several mm – cm in diameter
Cysts enlarge – contain blood and pus - destroy
surrounding tissue
Polycystic Kidney
Clinical Manifestation:
Symptoms appear when the cysts begin to enlarge
Abdominal and/or flank pain
Palpable enlarged kidneys
Hematuria
UTI
Hypertension
Diagnosis:
Family History, IVP, ultrasound, CT scan
Usually progresses to end-stage renal
failure
Renal Artery Stenosis
Partial occlusion of one or both renal arteries
Atherosclerotic narrowing or fibromuscular
hyperplasia
1-2% of hypertension
Diagnosis: Renal arteriogram
Therapy Goal:
Control hypertension
Restore kidney perfusion
Percutaneous transluminal renal angioplasty
Surgical revascularization (splenic artery or aorta)
Renal Artery Stenosis
Renal Tuberculosis
Rarely a primary lesion
Onset 5-8 years after primary pulmonary TB
Initially asymptomatic
Low grade fever, when infection descends to bladder:
polyuria, dysuria, epididymitis in men
Diagnosis: TB in Urine; IVP
Long Term: scarring of renal parenchyma & ureteral
strictures
Earlier the treatment – less likely renal failure will
occur
Five drugs: Isoniazid (INH), rifampin, pyrazinamide,
streptomycin, ethambutol
HIV—associated
Nephropathy
Range from mild fluid & electrolyte abnormalities to
progressive renal impairment and renal failure
10% incidence – highest among IV drug users
Clinical Manifestations:
Proteinuria & nephrotic syndrome
Progressive azotemia, enlarged kidney, rapid progression
to end-stage renal failure
Acute renal failure: most commonly seen in patients with
AIDS who is critically ill with HIV-related infection or
malignancy
Treatment: Depends on treatment of primary
disease - Dialysis
Nephrotic Syndrome
Decreased urine output
Proteinuria
Volume overload
CHF
Dysrhythmias
N/V
Uremic frost
Anemia
Vascular & Tubular
Pathogenesis
Nephrotic Syndrome
Increase in nitrogen waste in blood
Fluid and electrolyte disturbance
Treatment either conservative or
aggressive
Renal Disease
Assessment - Labs
Elevated BUN
Elevated creatinine
Elevated potassium
Elevated phosphate
Decreased calcium
Decreased HCO3 and pH
Renal Disease
Treatment
Conservative
Medication, diet & fluid restriction
Aggressive
Renal Replacement Therapies:
Dialysis (Peritoneal or Hemo)
Organ transplantation
Acute Renal Failure
4+ Pitting Edema
Renal Disease
Nursing Process
Assess: comprehensive pain assessment; monitor
urinary output—color, frequency, consistency, volume,
odor; neuro, CV—wt, edema, respiratory, skin
integrity; GI-abd girth
Nsg Action: Admin meds—pain relief, antibiotics,
treat HTN, fluid restriction versus hydration– IV & po;
hygiene; prepare for testing, procedures, surgery
Pt Education: Meds; nutrition, fluid restriction,
hygiene; pathology & strategies to promote adherence
Peritoneal Dialysis
Hemodialysis
Renal Transplant
Ureters
Renal pelvis holds 3-5 ml of urine
Kidney damage may result from backflow of more than
that amount of urine – REFLUX
UVJ (Ureteropelvic junction) – closes based on the
ureter’s angle of bladder penetration and muscle fiber
attachments to prevent backflow
During coughing or voiding – muscle fibers contract to
promote ureteral lumen closure
The bladder then contracts to further close the UVJ and
prevent urine from moving back through
Nephrolithiasis
500,000 people in US annually
20-55 years of age
More common in men than women
Except for struvite stones associated with UTI
No single theory can account for stone formation
Urinary pH, solute load, urinary stasis, urinary infection with
urea-splitting bacteria
Five major categories:
Calcium phosphate
Calcium oxalate
Uric acid
Cystine
Struvite
Risk Factors for the
Development of Renal Calculi
 Metabolic:
 Increased urine levels of calcium, oxaluric acid, uric acid, citric acid
 Climate:
 Warm climates cause increase fluid loss, low urine volume, and
increased solute concentration in urine
 Diet:
 Proteins that increase uric acid excretion
 Excessive amounts of tea or fruit juices that elevate urinary oxalate level
 Large intake of calcium and oxalate
 Low fluid intake
 Genetic Factors:
 Family history of stone formation, cystinuria, gout, renal acidosis
 Lifestyle:
 Sedentary occupation, immobility
Types of Renal Calculi
Renal Calculi
Clinical Manifestation:
Abdominal or flank pain
Hematuria
“Renal Colic” – passing into the ureter
Nausea & vomiting
Chills, fever
Diagnosis:
UA, Urine C&S, IVP, retrograde pyelogram,
ultrasound, cystoscopy
Renal function: BUN, Serum Creatinine
Renal Calculi
Medical Management:
Acute: treat pain, infection, obstruction
Narcotics, for fluids—IV and po, strain urine
Evaluate cause of stone formation: history, stone
analysis
Adequate hydration, dietary NA+ restriction, dietary
changes, medication
Treatment of struvite stones: control of infection
Renal Calculi
Removal
Indications for Endourologic, lithotripsy or open
surgical stone removal:
Stones too large for spontaneous passage
Stones associated with bacteriuria or symptomatic
infection
Stones causing impaired renal function
Stones causing persistent pain, nausea, or ileus
Inability of patient to be treated medically
Patient with one kidney
Renal Calculi
Removal
Endourological Procedures
Cystoscopy – remove stones from bladder
Cystolitholapaxy – cysto with lithotrite (stone
crusher) – then flushed out of bladder
Cystoscopic lithotripsy – cysto with pulverize stones
Flexible ureteroscopes: remove stones from ureter,
kidney pelvis – may be used with ultrasound,
electrohydraulic, or laser lithotripsy
Percutaneous nephrolithotomy -- nephrostomy tube
left in place for a period of time
Percutaneous Nephrostomy
Renal Stents
Incisions for Kidney
Surgery
Renal Calculi
Removal
Invasive Lithotripsy
Percutaneous ultrasonic lithotripsy – via
percutaneous nephroscope
Electrohydraulic lithotripsy – percutaneous
Laser lithotripsy probes – lower ureteral and large
bladder stones
Non-invasive - Extracorporeal shock-wave
lithotripsy
Patient is anesthetized
High-energy acoustic shock waves shatter stone
without damaging surrounding tissue
Lithotripsy
Renal Calculi
Nursing Diagnoses
Acute pain
Anxiety r/t uncertain outcome
Ineffective therapeutic regimen management
Impaired urinary elimination
Risk for infection
Renal Calculi
Nursing Management
Assess: Pain—guarding, pain scale, occurrence—
colic versus ongoing, tenderness on palpation;
History: recent/chronic UTI, immobility, gout,
hyperparathyroidism, prostatic hyperplasia; family
history of calculi; urine output; oliguria, hematuria;
labs—BUN, CR, UA, Urine C&S, Increased uric acid,
calcium
Action: Relieve pain; Treat UTI; Admin meds; Force
fluids PO - >2L/day; Maintain IV patency; strain urine;
position of comfort
Pt Education: Rationale for treatment; Measures to
prevent future recurrence (once calculi origin is
determined)—dietary restrictions (purine, calcium,
oxalates
Renal Calculi
Nutritional Therapy
Foods high in purine, calcium, or oxalate:
Purine:
High: Sardines, herring, mussels, liver, kidney, goose,
venison, meat soups sweetbreads
Moderate: Chicken, salmon, crab, veal, mutton, bacon,
pork, beef, ham
Calcium: milk, cheese, ice cream, yogurt, sauces
containing milk, all beans (except green beans),
lentils, fish with fine bones (sardines, kippers herring,
salmon); dried fruits, nuts, chocolate, cocoa, Ovaltine
Oxalate: spinach, rhubarb, asparagus, cabbage,
tomatoes, beets, nuts, celery, parsley, runner beans,
chocolate, cocoa, instant coffee, Ovaltine, tea;
Worcestershire sauce