CNM - GU System (DUGAN)

reddish-brown semilunar shaped positioned on either side of the vertebral column from T12-L3 vertebrae

Describe kidneys

11cm in length, 3cm thick, 6cm wide

What is the average length, thick, and width of kidneys?

left

Which kidney is larger?

right

Which kidney is lower?

metabolic waste is drained from them by ureters which empty into the bladded and are excreted from the body

What is the main function of the kidneys?

24-30cm in length and 0.9cm diameter

Ureters are tubular structures that average _____ length and ____ diameter

retroperitoneal

The kidneys are considered _____ organs

between the muscles of the back and peritoneal cavity; allows kidneys to be exposed surgically without opening the peritoneal cavity

Where are the kidneys located? Why is it good?

1. filter blood

2. excrete waste

3. control fluid volume and ion composition

4. regulate blood pressure

4. influence RBC production

5. regulate pH of blood and body fluids

List the 5 functions of the kidneys

1. nephrons

2. cortex

3. medulla

4. hilum

What are the 4 main components of the kidneys?

microscopic functional unit of the kidney (more than 1 million nephrons in each kidney)

Nephron

1. filtration

2. reabsorption

3. secretion functions

What is the nephron responsible for?

1. glomerulus

2. renal tubule

What are the two parts the nephron consists of?

nephron

This is an image of a

afferent arteriole

What is the arrow pointing at?

arcuate artery

What is the arrow pointing at?

arcuate vein

What is the arrow pointing at?

ascending limb

What is the arrow pointing at?

collecting duct

What is the arrow pointing at?

bowmans capsule

What is the arrow pointing at?

descending limb

What is the arrow pointing at?

distal convoluted tubule

What is the arrow pointing at?

efferent arteriole

What is the arrow pointing at?

glomerulus

What is the arrow pointing at?

interlobar artery

What is the arrow pointing at?

interlobar vein

What is the arrow pointing at?

nephron loop (loop of henle)

What is the arrow pointing at?

peritibular capillary

What is the arrow pointing at?

proximal convoluted tubule

What is the arrow pointing at?

cortical and juxtamedullary

What are the two types of nephrons?

80% and have a shorter loop of henle

What percentage of all nephrons is cortical? What's it's difference?

20% and have longer loop of henle that extends further in medulla

What percentage of all nephrons are juxtamedullary? What's it's difference?

1. blood enters glomerulus through afferent arteriole

2. it's filtered in glomerulus

3. then passes into bowman's capsule

4. then drains into proximal convoluted tubule

5. it travels through nephron loop into the distal convoluted tubule

6. then exits through the collecting duct into renal calyces and pelvis forming urine

Explain the step by step passageway of blood through a nephron.

protein free plasma

What is glomerulus filtrate?

proximal convoluting tubule

The bowmans capsule is an expanded portion of what?

false, composition changes as the tubules reabsorb liquid and have secretions added

T/F The filtrate in the tubules is the same composition as it is when it's in the glomerulus.

1. nephron

2. glomerulus

3. PCT and DCT where most kidney function occurs (1-2cm thick)

What does the cortex consist of?

1. tubules

2. nephron loop

3. renal pyramids

4. renal columns

What does the medulla consist of?

major and minor calyxes, connects to hilum

What does the pelvis consist of?

entry and exist site for the structures servicing the kidney

What is the function of the hilum?

medulla

What is the arrow pointing at?

cortex

What is the arrow pointing at?

renal artery

What is the arrow pointing at?

renal vein

What is the arrow pointing at?

renal pelvis

What is the arrow pointing at?

renal capsule

What is the arrow pointing at?

ureter

What is the arrow pointing at?

hilum

What is the arrow pointing at?

1. blood vessels

2. lymphatic vessels

3. ureter

What structures converge at the hilum?

renal pelvis, which is the upper expanded end of the ureter and where major calyces are joined

What renal structure does the hilum contain?

1. renal artery

2. afferent arterioles

3. glomeruli

4. efferent arterioles

5. renal vein

List the renal structures that blood flows through in the kidney starting with the renal artery

blood flow

All renal function is dependent upon adequate

exocrine and endocrine

Kidneys are responsible for what two main functions?

regulates volume and composition of plasma and fluid through filtration, tubular secretion, and tubular reabsorption and elimination of metabolic waste products primarily urea into urine

What are the functions of exocrine system?

renal control of sodium chloride excretion

What is the main determinant of extracellular fluid volume?

1. acid base balance

2. phosphate

3. potassium

4. calcium

List what the exocrine regulates in regards to plasma concentrations?

1. regulates blood pressure(vasodiliation)

2. RBC production

3. calcium homeostasis

4. prostaglandin synthesis

What are the endocrine functions?

afferent arteriole is larger in diameter than efferent arteriole

What greats a pressure gradient across the capillary walls?

very thin walls that are more permeable than tissue capillaries

What is unique about glomerulus capillaires?

some is filtered through the capillary membranes into bowmans capsule, and travels through renal tubules and the rest leaves through the efferent arteriole

When there is proper pressure gradient what happens with the plasma?

double-walled cup shaped structure surrounding the glomerulus of each nephron of the kidney

Describe bowmans capsule

filters to remove organic wastes, excess inorganic salts and water

What is the bowmans capsule function?

occurs in tubules and reabsorbs substances to return them into the circulation via peritubular capillaries

How does tubular reabsorption work?

occurs in tubules and allows movement of certain substances out of the blood in the peritubular capillaries and into the distal tubules then to collecting ducts

How does tubular secretion/excretion work?

regulates renal blood flow and glomerular filtration

What is the function of renin?

lower blood pressure by blocking angiotensin 1 from converting to angiotensin 2

What is the purpose of ACE inhibitors such as captopril? How?

is also reduced, resulting in a lower GFR

If afferent arteriole pressure is reduced, then the pressure in the glomerulus

releasing renin which is secreted by the juxtaglomerular apparatus

How do the kidneys respond to a lower GFR occuring?

angiotensinogen into angiotensin 1

What does renin convert?

peptide produced by the liver

What is angiotensinogen?

angiotensin converting enzyme (ACE)

What converts angiotensin I to angiotensin II?

vasoconstricts efferent arteriole increasing the pressure gradient causing higher blood pressure and an increased GFR

What does angiotensin 2 do?

decreased renal perfusion pressure, which decreases afferent arterioles pressure, decreasing filtration pressure and GFR

Renal artery stenosis (RAS) results when?

between afferent and efferent arterioles

Where is the juxtaglomerular apparatus located?

renin production and secretion controlling renal blood pressure

What is the juxtaglomerular apparatus function?

proximal, nephron loop, distal convoluted

What are the three primary renal tubules?

reabsorbs 2/3 of water and salts, all amino acids, glucose, and regulate pH filtrate

What is the function of the proximal convoluted tubule?

nephron removes water and solutes from the tubular fluid and returns them to the circulating blood

Reabsorption Definition

concentrates urine by reabsorbing water in descending loop, and salt ions in ascending loop

What is the function of the loop of henle (nephron loop)?

regulates potassium, sodium, calcium, and pH (only 1% of water in original filtrate is still present after passing through it)

What is the function of the distal convoluted tubule?

receives fluid from the DCT and the duct then empties into the renal calyces, renal pelvis, ureter, and then bladder

What is the function of the collection ducts?

95% water, nitrogenous wastes, hormones, blood or glucose (last two not normal)

Urine consists of?

1200-1600mL/day

How much urine is produced in a day?

kidney function impairment, RAS, obstructive, non-obstructive dilatation of renal pelvis, prevoid and postvoid, renal viability, uretal reflux, basically any renal issue

Indications for a renal scan?

horseshoe kidney (0.2%)

What is a anomaly with the kidneys?

anterior pelvic region

Where is a kidney transplant located?

neobladder, urostomy, nephrostomy

What are bladder change disorders?

thick kidneys with salt retention and edema

Glomerulonephritis

bacterial injection of the urinary tract

UTI (urinary tract infection)

infected urethra

Urethritis

bladder infection

Cystitis

infection from bacteria causes renal scarring

Pyelonephritis(kidney)

trauma, ingestion of a nephrotoxin, compromised blood flow to kidneys, urinary flow obstrction

Acute Renal Failure

causes necrosis of epithelium of tubules from things like mercury, lead, carbon tetrachloride

What does ingesting a nephrotoxin cause? What causes it?

kidney blood supply is cut off and tissue becomes necrotic

Explain renal infarct

simply kidney cysts (1:5 chance if over 50yrs) or polycystic disease

What are the types of kidney cysts?

inherited and cysts enlarge kidney and lose function over time

Explain polycystic disease

most common where there's a blockage where the ureter meets the kidney

Urinary Pelvic Junction (UPJ) Obstruction

blockage where the ureter meets the bladder

Ureterovesical Junction (UVJ) Obstruction

ureter is dilated, but with diuretic urine can clear

Dilated Non-obstructed kidney