Urinary SystemsUrinary Systems

Allied Health Science 1Allied Health Science 1

Mrs. LewisMrs. Lewis

Functions of the Urinary Functions of the Urinary SystemSystem

Excretion- removing nitrogenous Excretion- removing nitrogenous waste, certain salts and excess waste, certain salts and excess water from blood.water from blood.

Maintain acid-base balanceMaintain acid-base balance Secrete waste products in the form Secrete waste products in the form

of urineof urine Eliminate urine from bladderEliminate urine from bladder

KidneysKidneys

Bean-shaped organsBean-shaped organs Located b/w peritoneum and the Located b/w peritoneum and the

back musclesback muscles Renal Pelvis- funnel shaped Renal Pelvis- funnel shaped

structure at the beginning of the structure at the beginning of the ureter.ureter.

MedullaMedulla

Inner, striated layer of the kidneyInner, striated layer of the kidney Triangular shaped division of the Triangular shaped division of the

medulla are called Pyramids.medulla are called Pyramids. Base of the each pyramid faces Base of the each pyramid faces

cortex, while apex empties into cortex, while apex empties into cuplike cavities called Calycles.cuplike cavities called Calycles.

Cortex and NephronCortex and Nephron Is composed of millions of microscopic Is composed of millions of microscopic

functional units called nephrons.functional units called nephrons. The nephron is the functional unit of the The nephron is the functional unit of the

kidneykidney.. Its parts include:Its parts include:

– Bowman’s capsuleBowman’s capsule– Glomerulus- cluster of capillaries that Glomerulus- cluster of capillaries that

Bowman’s capsule surrounds.Bowman’s capsule surrounds.– Proximal Convoluted tubuleProximal Convoluted tubule– Loop of HenleLoop of Henle– Distal convoluted tubuleDistal convoluted tubule– Collecting tubuleCollecting tubule

Urine Formation in the Urine Formation in the NephronNephron

Filtration Filtration Re-absorption Re-absorption

SecretionSecretion

FiltrationFiltration First step in urine formationFirst step in urine formation Blood from renal artery enter glomerulus (which Blood from renal artery enter glomerulus (which

filters substances from the blood).filters substances from the blood). High blood pressure in glomerulus forces fluid to High blood pressure in glomerulus forces fluid to

filter into Bowman’s capsule (cup-shaped filter into Bowman’s capsule (cup-shaped structure on the upper area of a nephron). structure on the upper area of a nephron).

Filtrate does not contain plasma proteins or Filtrate does not contain plasma proteins or RBCs- they are too big. RBCs- they are too big.

Bowman’s capsule filters out 125cc of fluid/min.- Bowman’s capsule filters out 125cc of fluid/min.- 7500cc/hr7500cc/hr

As filtrate continues through nephron, 90% of As filtrate continues through nephron, 90% of water is reabsorbed. water is reabsorbed.

Re- AbsorptionRe- Absorption

A useful substance filter out of the renal A useful substance filter out of the renal tubules and back into the capillaries around tubules and back into the capillaries around the tubules. the tubules.

Water and useful substances are reabsorbed. Water and useful substances are reabsorbed. If blood levels of certain substance are high If blood levels of certain substance are high

(glucose, amino acids, vitamins, sodium) (glucose, amino acids, vitamins, sodium) then these substances will not be then these substances will not be reabsorbed.reabsorbed.

Glucose is not normally secreted in the Glucose is not normally secreted in the urine. urine.

SecretionSecretion

Opposite of reabsorption.Opposite of reabsorption. Secretion transports substances from Secretion transports substances from

blood into collecting tubules.blood into collecting tubules. Substances include creatinine, Substances include creatinine,

hydrogen ions, potassium ions, and hydrogen ions, potassium ions, and some drugs.some drugs.

Electrolytes are selectively secreted Electrolytes are selectively secreted to maintain body’s acid-base balance.to maintain body’s acid-base balance.

Urinary OutputUrinary Output

Average= 1500ml/dayAverage= 1500ml/day Urinalysis- examination of urine to Urinalysis- examination of urine to

determine presence of blood cells, determine presence of blood cells, bacteria, acidity level, specific bacteria, acidity level, specific gravity and physical characteristics gravity and physical characteristics (color, clarity and odor)(color, clarity and odor)

UretersUreters

One from each kidneyOne from each kidney Carry urine from kidney to bladderCarry urine from kidney to bladder Smooth muscles tube with mucous Smooth muscles tube with mucous

membrane liningmembrane lining Peristalsis pushes urine down Peristalsis pushes urine down

ureters.ureters.

Urinary BladderUrinary Bladder Located in the pelvic cavity. Located in the pelvic cavity. Function is to store and aid the elimination of Function is to store and aid the elimination of

urine.urine. Hollow, muscular organHollow, muscular organ Made of elastic fibers and involuntary muscleMade of elastic fibers and involuntary muscle Stores urine- usually about 500ccStores urine- usually about 500cc Emptying urine (voiding) is involuntary but Emptying urine (voiding) is involuntary but

controlled through nervous system controlled through nervous system (voluntary)(voluntary)

Urine leaves through urethra to outside Urine leaves through urethra to outside opening= urinary meatus.opening= urinary meatus.

Control of Urinary Control of Urinary SecretionSecretion

ADH and aldosterone control the production of ADH and aldosterone control the production of urine. urine.

Reabsorption of H20 is distal convoluted tubule Reabsorption of H20 is distal convoluted tubule controlled by ADH (antidiuretic horomone).controlled by ADH (antidiuretic horomone).

Secretion and regulation of ADH controlled by Secretion and regulation of ADH controlled by hypothalamus.hypothalamus.

Aldosterone is secreted by adrenal cortex, Aldosterone is secreted by adrenal cortex, promotes excretion of potassium and hydrogen promotes excretion of potassium and hydrogen ions, reabsorption of sodium, chlroine ions and ions, reabsorption of sodium, chlroine ions and H20.H20.

Renin is a horomone released by kidneys, Renin is a horomone released by kidneys, stimulates release of aldosterone from adrenal stimulates release of aldosterone from adrenal cortex.cortex.

Diuretics inhibit reabsorption of H20.Diuretics inhibit reabsorption of H20.

Nervous ControlNervous Control

Direct control through nerve Direct control through nerve impulses on kidney blood vessels.impulses on kidney blood vessels.

Indirect control through stimulation Indirect control through stimulation of endocrine glands. of endocrine glands.

Disorders of the Urinary Disorders of the Urinary SystemSystem

Acute Kidney FailureAcute Kidney Failure– Caused by nephritis, shock, injury, Caused by nephritis, shock, injury,

bleeding, sudden heart failure or bleeding, sudden heart failure or poisoning.poisoning.

– Symptoms- early sign=oliguria (scant Symptoms- early sign=oliguria (scant urine) or anuria (no urine produced).urine) or anuria (no urine produced).

– Supression of urine formation can lead to Supression of urine formation can lead to uremia which is toxic condition when uremia which is toxic condition when blood retains urinary waste products.blood retains urinary waste products.

Chronic Renal FailureChronic Renal Failure– Gradual loss of function of nephrons.Gradual loss of function of nephrons.

Disorders of the Urinary Disorders of the Urinary System continued…System continued…

Glomerulonephritis Glomerulonephritis – Inflammation of glomerulusInflammation of glomerulus– Filtration process affectedFiltration process affected– Plasma proteins are filtered through and found in urine, Plasma proteins are filtered through and found in urine,

RBCs too (Hematuria).RBCs too (Hematuria).– Can be acute (caused by a bacteria) or chronic (when Can be acute (caused by a bacteria) or chronic (when

there is permanent damage). there is permanent damage). HydronephrosisHydronephrosis

– Urine backs up because of blockage in ureter, renal Urine backs up because of blockage in ureter, renal pelvis and calyces become distended.pelvis and calyces become distended.

– Can be due to kidney stones.Can be due to kidney stones.– Can also be caused by pregnancy or enlarged prostate.Can also be caused by pregnancy or enlarged prostate.– Treatment- remove the causeTreatment- remove the cause

Disorders of the Urinary Disorders of the Urinary System continued…System continued…

PylonephritisPylonephritis– Inflammation of kidney tissue and renal pelvisInflammation of kidney tissue and renal pelvis– Usually caused by infection from uretersUsually caused by infection from ureters– One symptom is pyuria (pus in urine).One symptom is pyuria (pus in urine).– Treatment= antibioticsTreatment= antibiotics

Renal Calculi (Kidney Stones)Renal Calculi (Kidney Stones)– Made of crystals of calcium phosphate and uric Made of crystals of calcium phosphate and uric

acid.acid.– Gradually they get larger until they block ureters- Gradually they get larger until they block ureters-

obstructionobstruction– First symptom- severe pain, can cut living of the First symptom- severe pain, can cut living of the

ureters or urethra.ureters or urethra.– Other symptoms include nausea and vomiting, Other symptoms include nausea and vomiting,

frequency, chills, fever, and hematuria.frequency, chills, fever, and hematuria.– Diagnosis- by symptoms ultrasound, or x-rayDiagnosis- by symptoms ultrasound, or x-ray– Rx= increase fluids to flush out stone, Rx= increase fluids to flush out stone,

medications, and if needed- Lithotripsymedications, and if needed- Lithotripsy

Disorders of the Urinary Disorders of the Urinary System continued…System continued…

LithotripsyLithotripsy– Surgical procedure to remove kidney stonesSurgical procedure to remove kidney stones– Shock waves hit dense stones and break them upShock waves hit dense stones and break them up– Done on outpatient basisDone on outpatient basis

CystitisCystitis– Inflammation of the mucous membrane lining of the Inflammation of the mucous membrane lining of the

urinary bladderurinary bladder– Most common cause- E. ColiMost common cause- E. Coli– Symptoms- dysuria (painful urination) and frequencySymptoms- dysuria (painful urination) and frequency– Usually found in females (shorter urethra)Usually found in females (shorter urethra)– Rx= antibioticsRx= antibiotics

Incontinence- involuntary urinationIncontinence- involuntary urination– Sometimes you would have to have a Foley catheterSometimes you would have to have a Foley catheter

Disorders of the Urinary Disorders of the Urinary System continued…System continued…

DialysisDialysis– Used for kidney failureUsed for kidney failure– Involves the passage of blood through Involves the passage of blood through

device with semi-permeable membranedevice with semi-permeable membrane– Dialysis serves as substitute kidneyDialysis serves as substitute kidney

HemodialysisHemodialysis– Used to treat kidney failureUsed to treat kidney failure– Blood from patient flows through Blood from patient flows through

machine and is filtered.machine and is filtered.– Usually a fistula is created (opening b/w Usually a fistula is created (opening b/w

vein and artery) for inserting needles.vein and artery) for inserting needles.– Can be done at home or in clinic.Can be done at home or in clinic.– Takes 2 to 4 hours, 2-3 times a week.Takes 2 to 4 hours, 2-3 times a week.

Disorders of the Urinary Disorders of the Urinary System continued…System continued…

Peritoneal DialysisPeritoneal Dialysis– Uses the peritoneal lining to filter blood.Uses the peritoneal lining to filter blood.– Dialysate (cleaning solution) flows in and out via tube.Dialysate (cleaning solution) flows in and out via tube.

Kidney TransplantKidney Transplant– Possible treatment for renal failurePossible treatment for renal failure– Is used for a last resortIs used for a last resort– Involves donor organ from someone with a similar Involves donor organ from someone with a similar

immune system.immune system.– Main complication- rejectionMain complication- rejection

Enuresis- bedwettingEnuresis- bedwetting Glycosuria- sugar in urineGlycosuria- sugar in urine Nocturia- frequent urination at nightNocturia- frequent urination at night Polyuria- large amounts of urine.Polyuria- large amounts of urine.

The End!!!!!!The End!!!!!!