Chapter 11: The Urinary System Flashcards
What’s the primary function of the urinary system?
Regulate extracellular fluids of the body (plasma and tissue fluid).
Define electrolyte:
Mineral salt of the body that carries an electrical charge and regulates nerve impulses, muscle contractions, hydration, and blood pH.
Define filtrate:
Fluid that passes from the blood through the capillary walls of the glomeruli to the Bowman capsule. Urine is formed from filtrate, which is similar to plasma with less protein.
Define nitrogenous waste:
Product of protein metabolism that includes urea, uric acid, creatine, creatinine, and ammonia.
Define peristaltic wave:
Sequence of rhythmic contractions of smooth muscles of a hollow organ to force material forward and prevent backflow.
Define peritoneum:
Serous membrane that lines the abdominopelvic cavity and covers most of the organs within the cavity.
Define pH:
Symbol that expresses the acidity or alkalinity of a solution. [acidic < 7 (neutral) < alkaline]
Define plasma:
Liquid portion of blood filtered by nephrons to remove dissolved waste.
What happens if the kidneys do not continuously remove wastes?
Death
What is erythropoietin?
Produced by the kidneys that stimulates RBC production in bone marrow when O2 levels are low.
Tell me about the kidneys:
Each are about the size of a fist, bean-shaped, and are retroperitoneal. In a cross-section view, they have an outer renal cortex and inner renal medulla.
Renal cortex
Outer layer of the kidneys (in a cross-section view)
Renal medulla
Inner layer of the kidneys (in a cross section view)
Nephrons
Microscopic filtering units of the kidneys.
Hilum (singular hilus)
An opening near the medial border of the kidneys through which the renal artery enters and the renal vein exits.
Renal pelvis
Hollow cavity where the ureter merges with the kidney.
Tell me about the ureters:
Each is ~10”-12” long; these carry urine in peristaltic waves to the bladder.
What is the urethral orfice?
Where the ureters meet the urinary bladder.
Tell me about the urinary bladder:
It’s an expandable, hollow organ that acts as a temporary reservoir for urine. It has small folds called rugae that expand as the bladder fills.
What’s the trigone?
Triangular area at the base of the bladder formed by the openings of the ureters and urethra; leads into the urethra.
Tell me about the urethra:
Tube that discharges urine from the bladder. ~1.5” in women and ~7-8” in men. In males, the urethra passes through the prostate gland and the penis.
What’s micturition?
urination
What’s the urinary meatus?
Opening in the urethra through which urine is excreted from the body.
About how many nephrons are there in a kidney?
1 million
Function of a nephron:
Maintain homeostasis by continually adjusting the volume, composition, and pH of blood plasma and tissue fluid. Each nephron contains a renal corpuscle and a renal tubule.
What’s a renal corpuscle?
Composed of tuft capillaries called the glomerulus that is surrounded by the Bowman capsule.
What is a renal tubule?
Connected to the renal corpuscle and consists of 4 structures:
1) Proximal convoluted tubule
2) Loop of Henle
3) Distal convoluted tubule
4) Collecting tubule
What does the collecting tubule do?
Transports newly formed urine to the renal pelvis for excretion from the kidneys.
What is the afferent arteriole?
Carries blood to the glomerulus.
What is the efferent arteriole?
Carries blood from the glomerulus. This passes behind the renal corpuscle to form the peritubular capillaries (capillaries that surround the renal tubule).
What are the 3 physiological functions of the nephron?
Filtration, reabsorption, and secretion.
What is filtration?
Occurs in the renal corpuscle as water, sugar, electrolytes, and other small particles in plasma in the afferent arteriole pass into the Bowman capsule to form filtrate.
What is reabsorption?
Begins as filtrate travels along the long, twisted path of the tubule. Most of the water, and some electrolytes and amino acids, from the tubule re-center the circulating blood through the peritubular capillaries.
What is secretion?
Final stage of urine formation; peritubular capillaries actively secrete waste products into the renal tubules for removal in urine. Urine then moves to the renal pelvis, to the bladder for temporary storage, then exits the body.
albumin/o
albumin; protein
azot/o
nitrogenous compounds
bacteri/o
Bacteria
cyst/o
vesic/o
bladder
glomerul/o
glomerulus
kal/i
potassium
kal/i/ur/esis: condition of potassium in the urine.
keton/o
ketone bodies (acids and acetones)
lith/o
stone; calculus
meat/o
meatus; opening
nephr/o
ren/o
kidney
noct/o
night
olig/o
scanty
py/o
pus
pyel/o
renal pelvis
ur/o
urine; urinary tract
ureter/o
ureter
urethr/o
urethra
-genesis
forming; producing; origin
-iasis
abnormal condition
-uria
urine
dia-
through; across
retro-
backward; behind
What are some common symptoms of urinary disease?
Changes in urination pattern, changes in urination output, and dysuria.
What’s urology?
Branch of medicine concerned with urinary disorders and diseases of the male reproductive system.
What’s a urologist?
Physician who specializes in the diagnosis and treatment of genitourinary disorders.
What’s nephrology?
Branch of medicine concerned specifically with diseases of the kidney, electrolyte imbalance, renal transplantation, and dialysis therapy.
What’s a nephrologist?
Physician who specializes in the diagnosis and treatment of kidney disorders.
Tell me about glomerulonephritis:
Inflammation of the glomerular membrane in the nephrons causing it to become leaky. This causes RBCs and proteins that normally remain in the blood to pass through the inflamed glomerular membrane and into the tubules. Most forms of this are the result of another disorder.
Tell me about nephrolithiasis:
Kidney stones. Causes urine to reflux into the renal pelvis b/c the stone blocks urine from passing into the bladder. Treatment includes extracorporeal shock wave lithotripsy (ESWL), or for more serious cases, percutaneous nephrolithotomy (PCNL).
Urolithiasis:
stones that form anywhere in the urinary tract.
Ureterolithiasis:
Stones in the ureter.
What’s the function of a nephrostomy tube?
Drains urine from the kidney during healing from surgery post-op.
Tell me about acute tubular necrosis (ATN):
Necrosis occurs in the tubules either from ingestion of toxic drugs (nephrotoxic ATN) or decrease in blood supply (ischemic ATN). Disorder is usually reversible when tubular damage isn’t severe.
What are the 2 types of bladder cancer?
1) Transitional cell carcinoma
2) Adenocarcinoma
Tell me about transitional cell carcinoma:
Accounts for ~95% of bladder cancers in the U.S. It affects the transitional cells that line the bladder, ureters, and urethra; these allow the bladder to expand/contract.
Tell me about adenocarcinoma:
Less common; only accounts for ~1% of bladder cancers in the U.S. and arises from the mucus secreting glands in the bladder (tends to be invasive).
What’s a transurethral resection of bladder tumor (TURBT)?
High energy laser device is passed through the urethra to destroy malignant tissue.
Anuria
Absence of urine production or output. May be obstructive or unobstructive.
Bladder neck obstruction (BNO)
Blockage at the base of the bladder that prevents urine from passing into the urethra. Causes may include enlarged prostate, bladder stones, or tumors.
Cystocele
Prolapsing or downward displacement of the bladder due to weakening of the supporting tissues between the bladder and vagina.
End-stage renal disease (ESRD)
Any type of kidney disease where there’s little or no renal function, requires patient to undergo dialysis or kidney transplant for survival. 2 most common causes are DM and HTN.
Enuresis
Involuntary discharge of urine; also called incontinence.
Nocturnal enuresis: enuresis that occurs at night.
Diurnal enuresis: occurs during the day.
Fistula
Abnormal passageway from a hollow organ to the surface or from one organ to another. Most common type is a vesicovaginal fistula.
Hydronephrosis
Abnormal dilation of the renal pelvis and calyces of 1 or both kidneys caused by pressure from accumulated urine that can’t flow past an obstruction in the urinary tract.
Interstitial cystitis (IC)
Chronic inflammation of the bladder wall that’s not caused by bacterial infection and isn’t responsive to traditional antibiotic therapy; also called painful bladder syndrome.
Nephrotic syndrome
Loss of large amounts of plasma protein, usually albumin, through the urine due to increased permeability of the glomerular membrane.
Neurogenic bladder
Impairment of bladder control as a result of brain, spinal cord, or nerve damage.
Polycystic kidney disease (PKD)
Inherited disease in which sacs of fluid called cysts develop in the kidneys. If there are many cysts great in size it can cause kidney failure.
Pyelonephritis
Infection of the kidney, usually as a result of infection that begins in the urethra or bladder and ascends the ureters into the kidney.
Urgency
Sensation of the need to void the bladder immediately. Commonly associated with UTI.
Urinary tract infection (UTI)
An infection, typically bacterial in origin, in any part of the urinary tract, including the kidneys (acute pyelonephritis), bladder (cystitis), or urethra (urethritis). Common symptom is dysuria.
Vesicoureteral reflux (VUR)
Disorder caused by failure of urine to pass through the ureters to the bladder, usually a result of impairment of the valve between the ureter and bladder or obstruction in the ureter.
Wilms tumor
Rapidly developing malignant tumor of the kidney that usually occurs in children; also called nephroblastoma. The tumor may metastasize in later stages.
Measures the contraction of muscles that control urination using electrodes placed in the rectum and urethra. Determines whether incontinence results from weak muscles or other causes.
Electromyography (EMG)
Examination of the urinary bladder for evidence of pathology, to obtain biopsies of tumors or other growths, or to remove polyps.
Cystoscopy (cysto)
Test that determines the amount of nitrogen in the blood that comes from urea, a waste product of protein metabolism. Helps evaluate kidney function.
Blood urea nitrogen (BUN)
Test that determines the causative organism of an infection and identifies how the organism responds to certain antibiotics. May be ordered when a patient has chronic bladder infections or if they’re unresponsive to treatment.
Culture & Sensitivity (C&S)
Urine screening test that includes physical observation, chemical tests, and microscopic evaluation. Provides info on urinary structures, and can be the first indicator of system disorders, such as DM and liver/gallbladder disease.
Urinalysis (UA)
Non-invasive, painless test that uses high-frequency sound waves to produce images of the bladder before and after urination to check for urinary retention.
Bladder ultrasound
Imaging of the urinary tract after IV injection of a contrast medium; also called excretory urography. Detects kidney stones, enlarged prostate, tumors, and injury post-trauma.
Intravenous pyelography (IVP)
Nuclear imaging test using a radioactive substance (tracer) injected IV to produce images of the kidneys. May be used to evaluate kidney transplant to identify signs of rejection.
Renal nuclear scan
X-ray of the bladder performed before, during, and after voiding using a contrast medium to enhance imaging. Can help identify structural abnormalities of the bladder or urethra.
Voiding Cystourethrography (VCUG)
Replacement of a diseased kidney with one that’s supplied by a compatible donor (usually a family member or cadaver).
Kidney transplant
Opening created between the skin and the kidney to drain urine through a tube to a collecting receptacle outside the body when the ureters are unable to do so.
Nephrostomy tube
Insertion of a thin, narrow tube into the ureter to prevent or treat obstruction of urine flow from the kidney. These require constant monitoring because they may lead to blockages, infections, or stone formation.
Ureteral stents
Filtering procedure used to remove fluid and waste products from the blood and correct electrolyte imbalances.
Dialysis
Dialysis in which an artificial kidney machine receives waste-filled blood, filters it using a solution called dialysate, and then returns the dialyzed (clean) blood to the patient’s bloodstream.
Hemodialysis
Toxic substances are removed from the body by using the peritoneal membrane as the filter by perfusing (flushing) the peritoneal cavity with warm, sterile chemical solution.
Peritoneal dialysis
This medicine treats bacterial infections of the urinary tract by acting on the bacterial membrane or one of its metabolic processes.
Antibiotics
This medicine decreases spasms in the bladder and urethra by relaxing smooth muscles in the lining of their walls, thus allowing normal emptying of the bladder.
Antispasmodics
This medicine promotes and increases the excretion of urine.
Diuretics
This medicine replaces potassium caused by depletion after diuretics.
Potassium supplements
ATN
acute tubular necrosis
BNO
bladder neck obstruction
BUN
blood urea nitrogen
C&S
culture and sensitivity
cysto
cystoscopy
EMG
electromyogram; electromyography
ESRD
end-stage renal disease
ESWL
extracorporeal shock wave lithotripsy
IC
interstitial cystitis
IVP
intravenous pyelogram; intravenous pyelography
pH
symbol for degree of acidity and alkalinity
PCNL
percutaneous nephrolithotomy
PKD
polycystic kidney disease
TURBT
transurethral resection of bladder tumor
UA
urinalysis
US
ultrasound; ultrasonography
UTI
urinary tract infection
VCUG
voiding cystourethrography
VUR
vesicoureteral reflux
