THE URINARY SYSTEM
Chapter 9 Page 274-294
Answer the questions as we go…
The Urinary System
• Homeostasis is the process through which the
body maintains a constant internal environment.
• The urinary system maintains the proper balance of
water, salts and acids in the body by filtering the
blood thru the kidneys…thereby maintaining
homeostasis
• Filters waste from protein metabolism (urea) and
muscle metabolism (creatinine)
• Converts waste products and excess water into
urine
Kidneys (renal = pertaining to kidneys)
•Filter 200 quarts of blood
every day to remove waste
products and excess water.
•This is urine (95% water,
5% waste)
•Kidneys also produce
hormones that have an
effect on B/P, RBC
production and Vitamin D
Kidneys
• Bean-shaped and located
in the retroperitoneal
space
• Renal cortex is the outer
region of the kidney
• Has > 1,000,000 nephrons
• Medulla is the inner region
of the kidney
• Contains urine-collecting
tubules
Nephrons
• Microscopic functional units of the kidney. - They
produce the urine
• Each nephron has a Glomerulus: cluster of capillaries
Production of urine
• Blood enters the kidney thru the renal
artery and goes to the nephrons
• It is then filtered by the glomerulus
• The now-filtered blood (blood cells
and proteins remain… too big to be
filtered) returns to the blood stream
through the renal vein.
• What was filtered out goes to the renal
tubules where a lot of the water, sugar,
salts are returned to the bloodstream
• The remaining waste products are
turned into urine and transported to
the renal pelvis and eventually to the
ureters.
Urinary Anatomy
• Ureters: 12” long tubes that
transport urine from kidney to
bladder
• Uses peristalsis
• Urinary Bladder: oval hollow
organ; reservoir for urine
• Urethra: Transports urine
from bladder to outside of the
body.
• Urethral meatus is the
external opening of the
urethra
• Urination is AKA voiding or
micturition (mik-chuh-rish-uhn)
For 2015: add ureteral orifices!!!
Nephropathology (disease of the kidney)
Renal failure
Inability of kidney(s) to perform
their functions. Nephrons cannot
be replaced!
• Uremia: AKA uremic poisoning –
kidney function compromised
and waste products are retained
in the blood
• Acute renal failure: Sudden onset
of uremia. Can be fatal. Cause is
kidneys not receiving enough
blood to filter from dehydration,
↓ B/P or ↓ blood volume from
injury, burns or severe infection
•
More Renal Failure
• Chronic renal failure:
progressive loss of renal
function over months or years.
• Diabetes, ↑ B/P, family hx, of
renal disease
• Build up of waste products can
lead to heart attacks or
strokes.
• End-stage renal disease: final
stage of chronic kidney disease.
Fatal without dialysis or a
kidney transplant.
Nephrotic Syndrome
• AKA Nephrosis: condition in
which excessive amounts of
protein are lost thru the urine.
Usually d/t damaged glomeruli
• Sx:
• Edema: excessive fluid
accumulation
• Hyperproteinuria: ↑ protein in
the urine
• Hypoproteinemia: ↓protein in
the blood
Pitting edema
Kidney
conditions
Kidney position while laying
down (a) and standing up (b)
• Hydronephrosis:
dilation(swelling) of
kidney(s) d/t backup of urine
from a blockage (kidney
stone or stricture of ureter)
• Glomerulonephritis:
inflammation of the
glomeruli that causes RBCs
and protein to leak into the
urine.
• Nephroptosis: AKA floating
kidney – prolapse (dropping
down) of a kidney into the
pelvic area when the patient
stands
More Kidney conditions
• Nephropyosis: suppuration (pus
formation) of the kidney
• Polycystic Kidney Disease (PKD):
Genetic, growth of numerous
fluid-filled cysts in the kidneys.
These cysts slowly replace much
of the mass of the kidney leading
to kidney failure
• Wilms tumor: rare malignant
kidney tumor, found in young
children, high cure rate if treated
early.
Stones (AKA calculus or calculi)
• Abnormal mineral deposit
• Vary in size from too small to notice (sand or
smaller) to marble like and very painful
• Nephrolithiasis: presence of kidney stones.
They are named based on where they lodge
•
•
•
Nephrolith – in kidney
Ureterolith (you-REE-ter-oh-lith) – ureter
Cystolith - bladder
• Renal colic: acute
pain in kidneys d/t
passage of a
nephrolith
Treatment of nephroliths
•Most small stones pass out of
the urinary tract on their own
within a few weeks…Painful!
•Extracorporeal shockwave
lithotripsy (ESWL): Most
common treatment, highenergy ultrasonic waves
traveling thru water or gel
break up the stone which is
then excreted
More nephrolith
treatments
• Percutaneous nephrolithotomy: Surgical
removal of a stone through a small incision
in the back.
•
Used if ESWL is unsuccessful, there is an
infection, or if the stone if really big.
• Ureteroscopy: (you-reet-eh-ROS-koh-pee)
Treatment of a stone lodged near the
ureter.
• Ureteroscope is inserted through the
urethra, thru the bladder and into the
ureter.
• Can remove the stone whole, but if too
big, can be cut with a laser.
Ureters
• Hydroureter: Blocked ureter causes
Hydroureter with end-stage
kidney disease
distention (swelling) with urine
• Always accompanies hydronephrosis
• Ureterectasis: distention of a ureter
• Ureterorrhagia: discharge of blood
from the ureter
Urinary Bladder
• Cystocele: AKA prolapsed bladder –
hernia of the bladder through the
vaginal wall. Cause:
pregnancy/childbirth
• Interstitial cystitis: chronic
inflammation within the walls of the
bladder.
• Vesicovaginal fistula: Abnormal
opening between bladder and vagina.
• Cause: prolonged labor/childbirth
• Fistula – abnormal opening between
two internal organs
Neurogenic bladder
• Urinary problem caused by interference with the
normal nerves associated with urination.
• Bladder may empty spontaneously (incontinence)
• Or, the bladder may not empty at all or may empty
incompletely resulting in retention or overflow
leakage
• Causes: nervous system tumor, trauma,
neuropathy, or an inflammatory condition
Prostate Gland
•Benign prostatic
hyperplasia (BPH) AKA
benign prostatic
hypertrophy or enlarged
prostate
•Usually in men >50
•Makes urination difficult
•Prostatism: disorder
from the compression or
obstruction of the
urethra d/t BPH
Enlarged prostates and urination
• Overflow incontinence: continuous leaking from the
bladder d/t being too full or not emptying completely.
• Prevalent in older men with enlarged prostates.
• Urinary hesitancy: difficulty in starting a urinary stream
• Common in older men with prostate problems
• In younger people, hesitancy may be caused by Bashful
bladder syndrome – inability to urinate near another
person
• Urinary retention: Aka ischuria (is-kūr´e-ah) – inability to
completely empty the bladder when urinating.
• Also associated with enlarged prostates
Urethra
•Urethrorrhagia: bleeding from the
urethra
•Urethrostenosis: narrowing of the
urethra
•Almost exclusive to men – scar
tissue from infection or injury
Abnormal urethral openings
• Congenital abnormalities:
• Epispadias:
• Male: urethral opening on the
upper surface of the penis
• Female: urethral opening near
the clitoris
• Hypospadias:
• Male: Urethral opening on
ventral (undersurface) of the
penis
• Female: Urethral opening in the
vagina
Urinary tract infections (UTI)
• Usually begins in the bladder, but can
affect all parts of the urinary system
• Usually bacterial (E. coli)
• More common in women b/c their
urethra is shorter and closer to the
rectum
• Cystitis: inflammation of the bladder
• Pyelonephritis: inflammation of the
renal pelvis and kidney – cause:
infection that has spread upward
• Urethritis- inflammation of the urethra
Urination
•Anuria: Absence of urine
•Kidney failure or obstruction
•Oliguria: scanty urination
•Dehydration, renal failure or
obstruction
•Polyuria: excessive urination
•Common symptom of diabetes
More on urination…
• Diuresis: Increased output of urine
• Dysuria: difficult or painful urination (UTI)
• Enuresis: Involuntary discharge of urine
• Nocturnal enuresis: urinary incontinence during
sleep. AKA bedwetting
• Nocturia: Frequent/excessive urination at night
• Inability to control the excretion of urine,
Incontinence
feces or both (urinary incontinence, fecal
incontinence)
• Stress incontinence: incontinence d/t
physical stress such as running, lifting,
sneezing, laughing or coughing. More
common in women than men
• Overactive bladder: Aka urge
incontinence
• Muscles of bladder contract
involuntarily resulting in urinary
frequency or accidental urination.
• Related to excessive caffeine or alcohol
consumption, UTIs neurological
disease, bladder/prostate problems.
Diagnostic Procedures
• Urinalysis: Examination of
urine to determine the
presence of abnormal
elements
• Cystoscopy: Visual exam of
the bladder with and
endoscope
• Cystoscopes are specialized
endoscopes that can remove
tumors or reduce an
enlarged prostate.
Catheterization
• Urinary Catheterization: Insertion of a tube into the
bladder
• Can be used to get a sterile urine specimen
• Or to drain urine from the bladder when the
patient is unable to urinate normally (indwelling)
• Or it can be used to place fluids into the bladder
(like chemotherapy medications or contrast
mediums)
• Suprapubic catheterization: catheter placed into
bladder thru a small incision in the abdominal wall
just above the pubic bone
• Foley catheter: most common type of indwelling
catheter
• Made of a flexible tube with a balloon filled with
sterile water on the end to hold it in place in the
bladder.
Radiographic Exams
•Cystography: X-ray exam
of the bladder after a
contrast medium is instilled
via a urethral catheter.
•Voiding
cystourethrography: dx
procedure using a
fluoroscope is used to
examine the flow of urine
from the bladder thru the
Abnormal! The dye should not
urethra.
flow up toward the kidneys
More Radiographic exams
• Intravenous pyelogram (IVP) –
Radiographic study of kidneys and
ureters
• Contrast medium put in an IV
• Can see stones, infections,
enlarged prostate, tumors,
injuries
• KUB (kidney, ureters, bladder)
• AKA flat-plate of the abdomen.
• No contrast medium used
• Shows bowel obstructions, stones
• Does not show ureters.
Dialysis
• Is a procedure to remove waste products and excess water from
the blood of a patient whose kidneys lo longer function
• Hemodialysis: Waste products are filtered directly from the
patient’s blood using an external hemodialysis unit (artificial
kidney)
• Peritoneal dialysis: The lining of the peritoneal cavity acts as a
filter to remove waste from the blood.
• Fluid is placed in the peritoneal cavity thru a catheter placed in
the abdominal wall.
• It is left there for a period of time to absorb the waste products
and then drained out
• This is repeated several times each day
Kidney
procedures
• Nephrolysis: Surgical freeing of a
kidney from an adhesion (band of
fibers that holds structures together
abnormally)
• Nephropexy: AKA nephrorrhaphy –
surgical fixation of nephroptosis
(floating kidney)
• Nephrostomy: Placement of a
catheter (tube) to maintain an
opening from the pelvis of the
kidney to the exterior of the body
• Used for draining urine from
kidneys with hydronephrosis.
• Or for gaining access to kidneys for
diagnostic procedures
More kidney procedures
• Pyeloplasty – Surgical repair
of the ureter and renal pelvis
(sometimes from
hydronephrosis)
• Pyelotomy: surgical incision
into the renal pelvis
• To correct obstructions such
as a stone lodged between
the renal pelvis and the
ureter.
• Neobladder: Replacement of
Urinary Bladder
a missing bladder created by
using about 20 inches of the
small intestines
• Ileal conduit: AKA a type of
ileostomy – use of a small
piece of intestine (ileum) to
convey urine from the ureters
to a stoma in the abdomen
• Cystopexy: Surgical fixation of
the bladder to the abdominal
wall.
Urethral
procedures
• Meatotamy: Surgical
incision made in the
urethral meatus to enlarge
the opening
• Urethropexy: surgical
fixation of the urethra to
nearby tissue. Often
performed to correct
urinary stress
incontinence.
• Urethrotomy: surgical
incision into the urethra
for relief of a stricture
Prostate Treatments
• Ablation: Removal of a body part or
the destruction of its function thru
surgery, hormones, drugs, heat,
chemicals, electrocautery, etc.
• Prostatectomy: surgical removal of
part or all of the prostate gland.
• Radical prostatectomy: removal of
the entire prostate
• Transurethral Prostatectomy
(TURP): Removal of excess tissue
from and enlarged prostate using a
resectoscope.
Urinary
Incontinence
Treatment
•Kegel exercises: pelvic
muscle exercises used
to strengthen the
muscles of the pelvic
floor
•Bladder retraining:
Behavior therapy in
which the patient learn
to urinate on a
schedule. Useful for
patients suffering from
urge incontinence.