Session 1A: Adrenal Glands, Urinary Tract And Posterior Abdominal Wall

Question 1

Where do the adrenal glands lie?

Answer 1

Close to the upper poke of each kidney. Right - behind liver and IVC
Left- behind stomach and pancreas

Question 2

What are the glands supplied by?

Answer 2

Three arteries:

1. Superior adrenal artery - branch of inferior phrenic artery
2. Middle adrenal artery - branch of AA
3. Inferior adrenal artery - branch of renal artery

Question 3

What are the adrenal gland drained by?

Answer 3

Single vein on each side:
Right adrenal vein - IVC
Left adrenal vein - left renal vein - IVC

Question 4

What is the adrenal gland composed of?

Answer 4

Cortex (outer) and medulla (inner)
Cortex produces steroid hormones including cortisol, aldosterone and testosterone
Medulla produces adrenaline

Question 5

Where are the kidneys located?

Answer 5

Extra-peritoneal structures (outside of peritoneum) and retro-peritoneal (behind)

One on Either side of upper lumbar vertebrae
Each kidney is embedded in perinephric fat and is covered by renal fascia
Another layer of paranephric fat over renal fascia

Question 6

What is on the medial border of the kidney?

Answer 6

Renal Hilum- where vessels, nerves, lymphatics and ureter enter or leave kidney

Question 7

What are the renal arteries and veins attached from and to?

Answer 7

Renal arteries - branches of AA
Renal veins - drain into IVC

Question 8

What is the internal aspect of the kidney composed of?

Answer 8

Cortex - outer
medulla - inner - arranged into pyramids
calyces

Question 9

What are the functional units of kidneys?

Answer 9

Nephrons - responsible for filtering blood, reabsorbing water and solutes and secreting and excreting waste products as urine

Question 10

What is in the cortex?

Answer 10

Glomeruli, glomerular capsules (bowman’s), proximal and distal tubules, and part of the collecting ducts

Question 11

What is in the renal pyramids?

Answer 11

Nephron loop (of henle) and the rest of the renal pyramids.

Question 12

What course does the urine take?

Answer 12

collecting ducts, renal papilla, minor calyx, major calyx, renal pelvis, ureter

Question 13

What is the function of the ureters?

Answer 13

carry urine to urinary bladder by peristalsis

Question 14

Where are the ureters?

Answer 14

In muscular walls
run anterior to psoas major on p.a.w
Across pelvic brim to enter pelvis

Question 15

What is produced in the cortex of the kidney?

Answer 15

produces steroid hormones incl cortisol, aldosterone and testosterone

Question 16

What is the urinary bladder like?

Answer 16

muscular organ
in pelvis below peritoneum
infra-peritoneal
posterior to pubic symphysis
anterior to vagina and rectum
bladder wall - smooth muscle known as detrusor - contracts to forcibly expel urine

Question 17

What si the function of the urinary bladder?

Answer 17

stores urine and helps squeeze urine out during micturition

Question 18

What si the function of the urinary bladder?

Answer 18

stores urine and helps squeeze urine out during micturition

Question 19

What is the blood supply of the urinary bladder?

Answer 19

vesical arteries
b of internal iliac artery

Question 20

What is the venous drainage of the urinary bladder?

Answer 20

Venous drainage
vesical veins - internal iliac vein

Question 21

What do the urethral sphincters do?

Answer 21

Internal and external urethral sphincters - control release of urine

Question 22

Where are the urethral sphincters? Control?

Answer 22

internal - base of bladder opens into urethra
smooth muscle/ involuntary control
external - inferior to prostate - males and deep perineal pouch - females
skeletal muscle /voluntary control

Question 23

What is the 3 innervation for the urinary bladder?

Answer 23

Somatic
Sympathetic
Parasympathetic

Question 24

What is the somatic innervation of the urinary bladder like?

Answer 24

somatic - b. Pudendal nerve (S2-S4)
conscious control - external urethral sphincter

Question 25

What is the sympathetic innervation of the urinary bladder like?

Answer 25

sympathetic - b. Hypogastric nerve (symp. T12-L2)
relaxation of detrusor/contraction of internal urethral sphincter

Question 26

What is the parasympathetic innervation of the urinary bladder like?

Answer 26

parasympathetic - pelvic splanchnic nerves (S2-4)
contraction of detrusor and relaxation of internal urethral sphincter - allows initiation of micturition

Question 27

What is the function of the urethra?

Answer 27

Urethra:
carries urine from the internal urethral orifice of the bladder to external urethral orifice.

Question 28

Where is the urethral in men and women?

Answer 28

Males - tip of penis - longer - pre,prostatic, membranous and penile parts - also carries semen
female - vestibule - relatively short

Question 29

Where is the posterior abdominal wall? (P.a.w) What does it include?

Answer 29

Region behind abdominal cavity

includes:
lumbar spine
psoas
quadratus lumborum

Question 30

Where do the ureters and gonad vessels descend?

Answer 30

ureters descend from kidneys - pelvis on psoas muscle
gonad vessels descend over ureters to supply gonads (testes or ovaries)

Question 31

What is the innervation that arises from the lumbar plexus?

Answer 31

L1-L4 = lumbar plexus:
iliohypogastric and ilioinguinal nerves - a.a.w + skin of external genitalia
Genitofemoral - skin of external genit
lateral femoral cutaneous - skin of lateral thigh
femoral nerve - s+m anterior thigh
obturator nerve - s+m medial thigh

Question 32

What does the thoracic aorta branch into?

Answer 32

Thoracic aorta - T12 - abdominal aorta - L+ R common iliac arteries (L4)
AA - Descends p.a.w - left of midline

Question 33

What are the paired and unpaired branches of the abdominal aorta ?

Answer 33

AA:
unpaired branches: SMA, IMA, coeliac trunk
Paired branches: renal, adrenal gonadal and lumbar arteries

Question 34

What is the venous drainage of the posterior abdominal wall?

Answer 34

venous drainage:
IVC - union of L+R common iliac veins (L5)
Ascends p.a.w - right of midline
Paired branches - IVC except left gonadal vein - left renal vein
IVC also receives hepatic veins - T8

Question 35

What is phaeochromocytoma?

Answer 35

Phaeochromocytoma
This is a rare hormone-producing tumour of the adrenal medulla. Secretion of excess adrenaline causes symptoms and signs related to hyperactivity of the sympathetic nervous system which are typically hypertension, tachycardia, and excessive sweating.

Question 36

What is the bladder stretch reflex?

Answer 36

Urination is controlled by centres in the cerebral cortex, brainstem and sacral spinal cord. The sacral spinal cord contains the sacral micturition centre. As the bladder fills, stretch of the bladder wall is detected and this is relayed to the sacral spinal cord via visceral afferent fibres. In the sacral spinal cord these fibres synapse directly onto motor neurons.

The motor neurons (via parasympathetic fibres in the pelvic splanchnic nerves) stimulate bladder contraction. This simple relay through the spinal cord, where bladder filling initiates bladder emptying, is a type of stretch reflex and is referred to as a reflex arc. In older children and adults, the reflex arc is inhibited by inputs from the cerebral cortex meaning older children and adults are aware of bladder filling and can consciously control when and where they urinate. This is achieved through ‘potty-training’ in early childhood, during which infants learn to consciously recognise bladder filling and develop descending pathways that inhibit the reflex when it is not convenient to urinate.

Question 37

How does injuries of the spinal cord cause bladder dysfunction?

Answer 37

Injuries of the spinal cord produce different patterns of bladder dysfunction, depending on the level of the injury. If a patient suffers an injury to their spinal cord above the sacral level (e.g. a spinal cord transection at the level of T10), two important pathways are interrupted:
1. ascending pathways conveying the sensation of bladder filling to the brain (so the patient is no longer aware of bladder filling).
2. descending pathways that exert voluntary, inhibitory control over the external urethral sphincter (so the external sphincter is permanently relaxed).

The reflex arc still functions below the injury, but the patient does not have any inhibitory control over it. The patient does not realise they need to pass urine and the bladder automatically empties as it fills, so the patient is incontinent of urine.

If a patient suffers an injury to the spinal cord or cauda equina at or below the level of the sacral micturition centre, the reflex arc itself is disrupted and the bladder fills with urine without emptying. The internal urethral sphincter is permanently contracted. As the bladder continues to fill, the pressure in the bladder eventually exceeds the strength of the internal urethral sphincter and urination will occur. This type of incontinence is ‘overflow incontinence’. If the pressure inside the bladder does not overcome the sphincter, the patient develops urinary retention. Eventually urine may back up to the ureters and kidneys if a urinary catheter is not placed.

Question 38

What is a UTI?

Answer 38

UTI - caused by bacteria (commonly E.coli) entering the urinary bladder via the urethra

More common in females as the female urethra is much shorter

Infection of urinary bladder = cystitis
Symptoms: burning pain on passing urine much more frequently

Infection may spread superiorly to the kidney - pyelonephritis
- more serious infection and often requires intravenous antibiotics
Symptoms include fever, flank pain, nausea and vomiting in addition to the symptoms of cystitis

Question 39

What is renal cancer like?

Answer 39

Renal Cancer
Cancer of the kidneys can be divided into three main types, based on their histological origin. Renal cell carcinomas (RCC) originate from the lining of the nephron, transitional cell carcinomas (TCC) arise from the epithelial lining inside the kidney, and Wilms’ tumours originate from renal stem cells. Renal cancers may present with a triad of symptoms: pain in the flank, a palpable mass in the abdomen and haematuria (blood in the urine). As the kidneys are encased in a renal capsule, perinephric fat, renal fascia and paranephric fat, a renal cancer must grow very large and penetrate these layers before it is able to invade adjacent organs and structures.

Question 40

What is renal cancer like?

Answer 40

Renal Cancer
Cancer of the kidneys can be divided into three main types, based on their histological origin. Renal cell carcinomas (RCC) originate from the lining of the nephron, transitional cell carcinomas (TCC) arise from the epithelial lining inside the kidney, and Wilms’ tumours originate from renal stem cells. Renal cancers may present with a triad of symptoms: pain in the flank, a palpable mass in the abdomen and haematuria (blood in the urine). As the kidneys are encased in a renal capsule, perinephric fat, renal fascia and paranephric fat, a renal cancer must grow very large and penetrate these layers before it is able to invade adjacent organs and structures.

Question 41

What is triple AAA?

Answer 41

Abdominal Aortic Aneurysm (AAA or ‘Triple A’)
An aneurysm is the bulging of a blood vessel caused by a weak point in the blood vessel wall. Risk factors for development of an abdominal aortic aneurysm (AAA) include smoking, alcohol, hypertension, and atherosclerosis. AAAs are diagnosed if the diameter of the aorta is wider than 3cm. If a AAA ruptures, significant intra-abdominal bleeding occurs rapidly, and mortality is high. If a small AAA is found incidentally (unexpectedly found during examination or imaging for another reason), they are monitored to see if they increase in size, and treatment, including surgery or stenting, may be offered if they become too large.

Question 42

What are calculi?

Answer 42

Kidney Stones (Calculi)
Hard stones (calculi) can form in the kidneys and pass into the ureter. Kidney stones are most often composed of calcium oxalate and risk factors for developing them include high urine-calcium levels, dehydration, obesity, and certain medications. Smaller stones can pass into the ureter and out of the body via the bladder and urethra without causing any problems, but larger stones can obstruct the ureter. The typical presentation of an obstructing stone in the ureter is excruciating, pulsatile pain felt from ‘loin to groin’. This is because the pain fibres supplying the ureters originate from the T12 to L2 nerves, so pain is referred and felt in the T12 - L2 dermatomes. If the flow of urine from the kidney is obstructed, the kidney will fill with urine and swell (hydronephrosis). This can injure the kidney and may also lead to infection.

The ureter narrows in three places, and these are the regions where stones are most likely to get stuck:
1. Pelvi-ureteric junction (PUJ) – between the renal pelvis and ureter.
2. Pelvic brim - where the ureter runs over the pelvic brim, anterior to the iliac artery.
3. Vesico-ureteric junction (VUJ) - where the ureter joins the bladder.

Question 43

What are calculi?

Answer 43

Kidney Stones (Calculi)
Hard stones (calculi) can form in the kidneys and pass into the ureter. Kidney stones are most often composed of calcium oxalate and risk factors for developing them include high urine-calcium levels, dehydration, obesity, and certain medications. Smaller stones can pass into the ureter and out of the body via the bladder and urethra without causing any problems, but larger stones can obstruct the ureter. The typical presentation of an obstructing stone in the ureter is excruciating, pulsatile pain felt from ‘loin to groin’. This is because the pain fibres supplying the ureters originate from the T12 to L2 nerves, so pain is referred and felt in the T12 - L2 dermatomes. If the flow of urine from the kidney is obstructed, the kidney will fill with urine and swell (hydronephrosis). This can injure the kidney and may also lead to infection.

The ureter narrows in three places, and these are the regions where stones are most likely to get stuck:
1. Pelvi-ureteric junction (PUJ) – between the renal pelvis and ureter.
2. Pelvic brim - where the ureter runs over the pelvic brim, anterior to the iliac artery.
3. Vesico-ureteric junction (VUJ) - where the ureter joins the bladder.