A&p - Chapter 26 - The Urinary System

Front 1

When a client with an indwelling urinary catheter wants to walk to the hospital lobby to visit with family members, the nurse teaches him how to do this without compromising the catheter. Which client action indicates an accurate understanding of this information?

a) The client sets the drainage bag on the floor while sitting down.

b) The client keeps the drainage bag below the bladder at all times.

c) The client clamps the catheter drainage tubing while visiting with the family.

d) The client loops the drainage tubing below its point of entry into the drainage bag

Back 1

B.

--Allows urine to flow by gravity

Front 2

How does the urinary system maintain homeostasis?

Back 2

-Managing the volume and composition of fluids, primary blood.

-Filter blood plasma, leaving water/solutes = produces urine

Front 3

What's different from the right kidney compared to the left kidney?

Back 3

The right kidney is lower because the right side of the liver is lower, which causes it to push it down.

Front 4

What are the parts of the urinary system?

Back 4

Kidneys, ureters, urinary bladder, urethra

Front 5

What are the functions of the kidneys?

Back 5

-Regulates blood volume and ionic composition (Na+, K+, Ca+, Cl-)

-Regulates blood pressure (renin), pH (H+, HCO3), and glucose levels.

-Maintains osmolality - 300 mmol/L (solutes)

-Produces 2 hormones (calcitriol (vit D) and erythropoietin (RBC))

-Excrete wastes in urine (drugs/toxins)

Front 6

What is the function of the ureters?

Back 6

Transport urine from kidneys to the urinary bladder.

Front 7

What is the role of urinary bladder?

Back 7

Stores urine and expels it into urethra.

Front 8

What is the role of the urethra?

Back 8

Discharges urine from the body.

Front 9

What protects the kidneys?

Back 9

-The retroperitoneal

- The lower ribs (11&12) between last thoracic and 3rd lumbar.

Front 10

What type of tissue is the external part of the kidney made of?

Back 10

Connective tissue

Front 11

Name the layers of the kidney from superficial to deep.

Back 11

Renal Fascia: anchors to other structures

Adipose Capsule: protects and anchors kidneys

Renal Capsule: continuous with ureter

Front 12

Name the diameters of the kidney.

Back 12

5-7cm wide

10-12cm long

Front 13

What is the indented area of the kidney called?

Back 13

The Hilum

Front 14

What enters/exits the renal Hilum.

Back 14

Renal artery

Renal vein

Ureter

Nerves

Lymphatics

Front 15

What is the renal cortex?

Back 15

The outer layer of the kidney.

Front 16

What is the renal medulla?

Back 16

The inner region of the kidney.

Front 17

What are the renal pyramids?

Back 17

Triangular shaped areas of the kidney that secrete apparatus and tubules.

Front 18

What are renal columns?

Back 18

They anchor to the cortex.

Front 19

What does parenchyma mean?

Back 19

The functioning part of an organ.

Front 20

What is nephroptosis?

Back 20

It is the inferior displacement or dropping of a kidney slipping from its normal position because it is not held in place by organs or fat.

Front 21

What happens with nephroptosis and very thin people?

Back 21

-Not enough fat to hold kidneys up.

-Ureter may kink and block urine flow, which causes pressure in the ureter and damage the tissue.

Front 22

How many people get nephroptosis?

Back 22

1/4 people

10x more common in women.

Front 23

What is the medical term for floating kidneys?

Back 23

Nephroptosis

Front 24

What is the path of urine drainage in the kidney?

Back 24

Collecting duct --> Papillary duct --> Minor calyx --> Major calyx --> Renal pelvis --> Ureter --> Urinary bladder

Front 25

What is the nephron?

Back 25

The main filtering system of kidneys.

Front 26

When does urine actually form during the path of urine drainage?

Back 26

In the calyxes (minor/major calyx)

Front 27

How much of the resting cardiac output enter the kidney?

Back 27

20-25% or 1200ml/minute

Front 28

What do the renal nerves primarily carry out?

Back 28

Sympathetic outflow

Front 29

What do the renal nerves do?

Back 29

Regulate blood flow through the kidneys.

Front 30

What is the filtering system of nephrons?

Back 30

The Glomerulus

Front 31

What vessels are part of the blood supply of nephrons?

Back 31

Cortical radiate artery

Arcuate artery

Interlobar artery

Segmental artery - only different one

Renal artery

Renal vein

Interlobar vein

Arcuate vein

Cortical radiate vein

Front 32

What is part of the renal corpuscle and what does it do?

Back 32

It filters the blood plasma.

Glomerular capsule (Bowman's capsule)

Glomerulus

Front 33

What is the flow of fluid through a cortical nephron?

Back 33

Glomerular (Bowman's) Capsule

Proximal convoluted tubule

Descending limb of the nephron loop

Ascending limb of the nephron loop

Distal convoluted tubule (drains into collecting duct)

Front 34

Where does Lasix take effect in the nephron?

Back 34

Loop of Henle

Front 35

What are the two types of nephrons?

Back 35

Cortical and juxtamedullary

Front 36

Which type of nephron is most abundant in the body?

Back 36

Cortical - 80%-85% of nephrons

Front 37

Where are the cortical nephrons, what are they and what do they do?

Back 37

-They're in the renal corpuscle in the outer portion of the cortex.

-They are short loops of Henle that extend only into the outer region of the medulla.

-They create urine with osmolarity similar to blood (should be 300) (dilated urine).

Front 38

Where are the juxtamedullary nephrons, what are they and what do they do?

Back 38

-They're in the renal corpuscle deep in the cortex with long nephron loops.

-They receive blood from the peritubular capillaries and vasa recta.

- They enable the kidney to secrete very concentrated urine in order to conserve water.

Front 39

What is the GFR rate?

Back 39

Glomerular Filtration Rate:

Amount of filtrate formed by both kidneys each minute.

(125ml per min. in men // 105ml per min. for women)

Front 40

Where does filtrate happen in the glomerulus and glomerular capsule?

Back 40

Between the visceral and parietal layer.

Front 41

Describe the renal corpuscle blood flow.

Back 41

It's fed by the afferent arteriole and it drains into the efferent arteriole.

The mesangial cells are contractile and help regulate glomerular filtration.

Front 42

Where are fenestrated capillaries found?

Back 42

In the kidneys, small intestine villi, the brain choroid plexuses, the ciliary process of the eye, endocrine glands.

Front 43

What do fenestrated capillaries help with?

Back 43

They don't allow protein or blood to go through.

Front 44

What happens if a patient has high blood pressure?

Back 44

If the pressure is too high, the solutes (protein, blood) will seep through and won't be reabsorbed.

Front 45

What do the fenestration (pore) of glomerular endothelial cell do?

Back 45

Prevents filtration of blood cells but allows all components of blood plasma to pass through.

Front 46

What does the basal lamina of glomerulus do?

Back 46

Prevents the filtration of larger proteins.

Front 47

What does the slit membrane between pedicels do?

Back 47

Prevents the filtration of medium-sized proteins.

Front 48

Where does the fluid filtered from the glomerular capillaries go?

Back 48

The capsular space.

Front 49

What regulates blood pressure and how?

Back 49

The juxtaglomerular apparatus (JGA) through vasoconstriction which reduces the volume in blood, thus reducing the blood pressure.

Front 50

What kind of cells are in the glomerular capsule?

Back 50

Simple cuboidal epithelial cells.

Front 51

What is part of the JGA?

Back 51

Juxtaglomerular cells and the macula densa, which is part of the ascending limb of nephron loop.

Front 52

What is the order of the parts in the nephron?

Back 52

Renal Corpuscle

Proximal Covluted Tubule

Loop of Henle:

Descending Nephron Loop

Ascending Nephron Loop

Distal Convoluted Tubule

Collecting Ducts

Front 53

What cells are in the distal collecting tubule and collecting duct?

Back 53

Principal and Intercalated cells

Front 54

What is the role of principal cells?

Back 54

They are receptors for ADH and Aldosterone

Front 55

What is the role of intercalated cells?

Back 55

To help manage blood pH.

Front 56

What are the 3 processes required to form urine?

Back 56

1) Glomerular filtration

2) Tubular reabsorption

3) Tubular Secretion

Front 57

What is the process of the excretion of a solute?

Back 57

1) Glomerular filtration

2) Secretion

3) Reabsorption

Front 58

What happens in glomerular filtration?

Back 58

1) Water and most solutes in blood plasma move across the wall of glomerular capillaries

2) Filtered

3) Move into glomerular capsule - then into the renal tubule.

Front 59

What happens in tubular reabsorption?

Back 59

1) Filtered fluid goes through the renal tubules & collecting ducts.

2) Tubule cells reabsorb 99% of filtered water and many of the solutes.

3) Water & solutes return to blood - peritubular capillaries and vasa recta (reabsorbed)

4) Reabsorption - substances to the bloodstream.

Front 60

What happens in tubular secretion?

Back 60

1) Along the renal tubule & collecting duct, substances such as wastes, drugs, & excess ions get secreted from peritubular capillaries into the renal tubule.

2) These substances ultimately make their way into the urine.

*Tubular secretion removes a substance from the blood.

Front 61

What controls the glomerular filtration?

Back 61

Blood pressure.

Front 62

What moves out of the glomerulus during filtration?

Back 62

Water and small molecules

Front 63

How much water in litres passes through the glomerular capsule?

Back 63

150-180L

Front 64

Why is the GFR important to know for nurses?

Back 64

If a patient has a high GFR, the medications given will not absorb because the substances are just passing through too fast.

If a patient has a low GFR, the kidneys aren't filtering the meds and nearly everything is reabsorbed, and some waste products are not adequately excreted.

Front 65

How do the kidneys maintain homeostasis?

Back 65

By maintaining a relatively constant GFR.

Front 66

What is the process called to regulate the GFR?

Back 66

Renal Autoregulation

Front 67

What is the myogenic mechanism in renal autoregulation?

Back 67

Stretching triggers contraction of smooth muscle cells in thewalls of afferent arterioles- (decreases renal blood flow) in response.

Front 68

What is the tubuloglemrular feeback?

Back 68

High GFR diminishes reabsorption.

Macula Densa inhibits release of nitric oxide, afferent arterioles constrict (decreases GFR).

Front 69

What type of fibers are the kidneys richly supplied by?

Back 69

Sympathetic fibers.

Front 70

What is neural regulation?

Back 70

Strong stimulation such as exercise or hemorrhage causes the afferent arterioles to constrict.

Urine output is reduced, and more blood is available for other organs.

Front 71

What is part of hormonal regulation?

Back 71

Angiotensin II

Atrial Natriuretic Peptide (ANP)

Front 72

How does Angiotensin II work?

Back 72

Angiotensin II constricts afferent and efferent arteries = diminishing GFR.

Front 73

What does Atrial Natriuretic Peptide do?

Back 73

Atrial Natriuretic peptide relaxes mesangial cells, increasing capillary surface area and GFR. ANP is secreted in response to stretch of cardiac atria.

Front 74

What converts angiotensin I and II?

Back 74

Renin

Front 75

What stops the conversion of angiotensin I and II?

Back 75

ACE inhibitor

Front 76

What happens to much of the filtrate and what are some examples of them?

Back 76

Much of the filtrate is reabsorbed active (pump) and passive (gradient) process.

Ex: water, glucose, amino acids, and ions

Front 77

What does secretion help with?

Back 77

Helps to manage pH and rid the body of toxic and foreign substances.

Front 78

What happens to the hormones during filtration?

Back 78

All the hormones work together during filtration.

Front 79

What are the hormones involved in hormonal regulation of tubular reabsorption and tubular secretion?

Back 79

Angiotension II

Aldosterone

Antidiuretic hormone (ADH)

Atrial natriuretic peptide (ANP)

Parathyroid hormone (PTH)

Front 80

What does Angiotensin II and where does it occur?

Back 80

Low blood volume/pressure stimulates renin to produce angiotensin II. This stimulates an increase of reabsorption of Na+, other solutes, and water, which increase blood volume/pressure.

Occurs in the proximal tubule cells.

Front 81

What does Aldosterone do and where does it occur?

Back 81

Increased angiotensin II and increased level of plasma K+ promote adrenal cortex to release aldosterone. This increases the secretion of K+ and reabsorption of Na+, Cl-, water, which increases blood volume/pressure.

Occurs in principal cells in the collecting ducts.

Front 82

What does Antidiruetic Hormone (ADH) and where does it occur?

Back 82

Increased osmolarity of extracellular fluid or decreased blood volume promotes release of ADH from posterior pituitary gland. This increases facultative reabsorption of water, which decreases osmolarity of body fluids.

This occurs in the apical membranes of principal cells.

Front 83

What does Atrial Natriuretic Peptide (ANP) do and where does it occur?

Back 83

Stretching of atria of heart stimulates ANP secretion. It increases the excretion of Na+ in urine (natriuresis); increases urine output (diuresis) and thus decreases blood volume/pressure.

This occurs in the proximal tubule and collecting ducts and inhibits secretion of aldosterone and ADH.

Front 84

What does the parathyroid hormone (PTH) do and where does it occur?

Back 84

It decreases the level of plasma Ca2+, promotes the release of PTH from parathyroid glands. This increases reabsorption of Ca2+.

This stimulates the opening of Ca2+ channels in distal tubule cells.

Front 85

KNOW THE TABLE WITH THE VALUES OF PLASMA, FILTRATE, AND URINE COMPOSITION

Back 85

SLIDE 38

Front 86

What are the parts of the reabsorption routes?

Back 86

Paracellular reabsorption and transcellular reabsorption

Front 87

What is paracellular reabsorption?

Back 87

Water and solutes in tubular fluid return to the bloodstream - they move between the tubule cells, making it PASSIVE.

Front 88

What is transcellular reabsorption?

Back 88

Water and solutes pass directly through the tubule cells, making it ACTIVE.

Front 89

How much is the obligatory water reabsorption?

Back 89

90%

Front 90

What does water follow?

Back 90

Water follows the solutes that are reabsorbed (ex; it follows Na+)

Front 91

What part of the nephron is permeable to water?

Back 91

Proximal tubule and descending loop of Henle.

Front 92

What is impermeable to water in the nephron?

Back 92

The loop of Henle, especially in ascending because ions are being absorbed and water cannot follow.

Front 93

What is the facultative water reabsorption?

Back 93

10%

Front 94

What regulates water reabsorption?

Back 94

ADH

Front 95

What happens when blood volume and blood pressure decrease?

Back 95

Renin/Angiotensin cause the walls of afferent arterioles to stretch less - juxtaglomerular cells secrete the enzyme renin into the blood.

Front 96

What does sympathetic stimulation do?

Back 96

Directly stimulates the release of renin from juxtaglomerular.

Front 97

What does renin do?

Back 97

Converts angiotensin I to angiotensin II by using the ACE enzyme, which causes:

-Decreased GFR

-Aldosterone keeps in water = higher BP

-Reabsorption of Na+, Cl-, & water tubules

Front 98

What do diuretics do?

Back 98

They slow renal reabsorption of water and thereby cause diuresis, an elevated urine flow rate, which in turn reduces blood volume.

Front 99

What do diuretic drugs treat?

Back 99

They treat hypertension by lowering the blood volume, which usually reduces blood pressure.

Front 100

What are some natural diuretics and what do they do?

Back 100

Caffeine - coffee, tea pop

They inhibit the reabsorption of Na+

Front 101

What does alcohol act as?

Back 101

A natural diuretic which inhibits the secretion of ADH.

Front 102

What are some examples of loop diuretics/ diuretics?

Back 102

Thiazide diuretics, chlorothiazide distal tubule, furosemide (Lasix)

Front 103

What happens if there is a high intake of urine production?

Back 103

There is a hgih volume of dilute urine.

Front 104

What happens if there is a low intake of urine production?

Back 104

There is a low volume of concentrated urine.

Front 105

What does homeostasis require in urinary production?

Back 105

Homeostasis requires maintenance of fluid volumes within specific limits.

Front 106

What varies with urine concentration?

Back 106

ADH

Front 107

How is dilute urine formed?

Back 107

Glomerular filtrate and blood have the same osmolarity - 300mOsm/L.

Front 108

Why does tubular osmolarity change in the formation of dilute urine?

Back 108

hDue to a concentration gradient in the meddula.W

Front 109

What happens to the urine when ADH is low?

Back 109

Urine is dilute with osmoloraity less than 300.

Front 110

What happens when ADH is high?

Back 110

It causes the kidney to produce small volumes of urine and it is concentrated with an osmolarity over 300.

Front 111

Describe the negative feedback loop of facultative reabsorption,the regulation of water (reabsorption by ADH).

Back 111

A stimulus disrupts homeostasis, increasing the osmolarity of plasma and interstitial fluid.

Osmoreceptors in the hypothalamus deliver nerve impulses to the CC (hypothalamus & posterior pituitary gland).

This increases the release of ADH, which allows the principal cells to become more permeable to water, which increases facultative water absorption.

The response is a decrease in plasma osmolarity which returns it to homeostasis by bringing the plasma osmolarity back to normal.

Front 112

What do we evaluate while analyzing the function of the kidney?

Back 112

Routine urinalysis primarily evaluates for the presence of abnormalities in the urine through urine C&S:

-Albumin (protein)

-Glucose

-RBC

-Ketone bodies

-Microbes / WBC

Front 113

Describe the characteristics of normal urine?

Back 113

Colour - Yellow or amber; varies with [urine] & diet. Concentrated urine is darker. Diet: reddish from beets, meds, & certain diseases. Kidney stones may produce blood in urine.

Turbidity:W

Front 114

What is the normal volume of urine in a day?

Back 114

1-2L/24hours ; varies considerablyW

Front 115

What is the normal colour of urine and what are some variations?

Back 115

Colour - Yellow or amber; varies with [urine] & diet. Concentrated urine is darker. Diet: reddish from beets, meds, & certain diseases. Kidney stones may produce blood in urine.

Front 116

What is normal turbidity in urine?

Back 116

Transparent when freshly voided; becomes turbid (cloudy) on standing.

Front 117

What is a normal odor for urine?

Back 117

Mildly aromatic; becomes ammonia-like on standing. Urine of diabetics has a fruity odor due to presence of ketone bodies.

Front 118

What is a normal pH level for urine?

Back 118

Ranges between 4.6 & 8.0 - average 6.0. It varies considerably with diet. High protein diets increase acidity; vegetarian diets increase alkalinity.

Front 119

What is a normal specific gravity (density) for urine?

Back 119

Specific gravity )density) is ratio of weight of volume of substance to weight of equal volume of distilled water. In urine, 1.001-1.035. The higher the concentration of solutes, the higher the specific gravity.

Front 120

How is urine transported from the kidneys to the urinary bladder?

Back 120

Each ureter transports urine from a renal pelvis by peristaltic waves, hydrostatic pressure, & gravity.

Front 121

How does the bladder prevent from overflowing with urine coming from the ureters?

Back 121

There is no anatomical valve at the opening of the ureter into the bladder, so when bladder fills, it compresses the opening and prevents backflow.

Front 122

What is the bladder and what is it's average capacity?

Back 122

The bladder is a hollow, distensible, muscular organ with a capacity averaging 700-800mL.

Front 123

Name the muscles of the bladder and what they do.

Back 123

Detrusor muscle (contracts to push urine into urethra)

Trigone

Front 124

What are the sphincters of the bladder?

Back 124

Internal Urethral sphincter (Involuntarily controls opening & closing of urethra)

External Urethral sphincter ( Voluntarily controls opening & closing of urethra)

Front 125

What does the peritoneum of the baldder do?

Back 125

Holds urinary bladder in place.

Front 126

What does the rugae of mucosa in the bladder do?

Back 126

Allows expansion of urinary bladder as it fills.

Front 127

What is micturition?

Back 127

The discharge of urine involves voluntary and involuntary muscle contractions.

Front 128

What do stretch receptors trigger in the bladder?

Back 128

A spinal reflex which we learn to control in childhood.

Front 129

Describe incontinence in infants and children (2-3yrs old)

Back 129

Incontinence is normal because neurons to the external urethral sphincter muscle are not completely developed.

Front 130

Describe incontinence in adults.

Back 130

Caused by stress, urges, overflow, and functional.

Front 131

What is stress incontinence?

Back 131

It is common in young & middle-aged females.

Results from weakness of the deep muscles of the pelvic floor.

Any physical stress that increases abdominal pressure such as coughing, sneezing, laughing, exercising, straining, lifting heavy objects, and pregnancy, causes leakage of urine from the urine bladder.

Front 132

What is urge incontinence?

Back 132

Most common in older people.

Characterized by an abrupt and intense urge to urinate followed by involuntary loss of urine.

May be caused by irritation of urinary bladder wall by infection, kidney stones, stroke, MS, spinal cord injury, or anxiety.

Front 133

What is overflow incontinence?

Back 133

Involuntary leakage of small amounts of urine caused by some type of blockage or weak contractions of the musculature of the urinary bladder.

When urine flow is blocked (ex: enlarged prostate or kidney stones), or when bladder muscles can no longer contract, bladder becomes overfilled and the pressure inside increases until small amounts of urine dribble out.

Front 134

What if functional incontinence?

Back 134

Urine loss resulting from the inability to get to a toilet facility in time as a result of conditions such as stroke, severe arthritis, or Alzheimer's disease.

Choosing the right treatment depends on correct diagnosis of the type of incontinence.

Treatments include Kegel exercises...

Front 135

What is dialysis?

Back 135

Blood cleaned artificially

-Blood hemodialysis filters the blood.

-Peritoneal dialysis - peritoneum of abdominal cavity - as dialysis membrane

Front 136

Name the urethras in males.

Back 136

Prostatic urethra

Intermediate urethra

Spongy urethra

Front 137

What is/are the difference(s) in urethras between males vs females?

Back 137

-The urethra is 5x longer in males than females.

-Urethra is divided into 3 segments in males but it's one short tube in females.

-Urethra is a common duct for urinary and reproductive system in males, but are separate in females.

Front 138

What happens with age in the urinary system?

Back 138

Kidneys shrink in size, which causes a decrease in blood flow, therefore filtering less blood.

The glomeruli becomes damaged or decrease in number.

The mass of both kidneys goes from 300g (20yrs) to 200g (80yrs).

Filtration rate declines by 50% between ages 40-70. By age 8-, 40% of glomeruli are not functioning = filtration, reabsorption and secretion decrease.

Acute & chronic kidney inflammations and renal calculi (kidney stones)

Sensation of thirst diminishes with age = susceptible to dehydration.

Weakening of bladder muscles.

UTI's, polyuria (excessive urine production), nocturia (excessive urination at night), increased frequency of urination, dysuria (painful urination), urinary retention or incontinence, and hematuria (blood in urine) are more common among the elderly.