ILA 9 - Renal Flashcards
What is in the renal tract?
Urinary tract = kidneys, ureters, bladder, urethra
Describe the anatomy of the kidneys
- Retroperitoneally from T12-L3
- Renal capsule, perirenal fat, renal fascia, pararenal fat
- Outer cortex and inner medulla
- Contains renal pyramids, at apex is called the renal papilla
- Each renal papilla has a minor calyx which collects urine from the pyramids, several merge to form a major calyx, urine passes through these to form a major calyx into the renal pelvis to the ureter and bladder
Describe the anatomy of the ureter
- 2 thick tubes, 25 cm long
- Smooth muscle, contracts to produce peristaltic waves = propels urine to the bladder
- continuation of renal pelvis, ureteropelvic junction is the narrowing
- drains into bladder
3 narrow sections = ureteropelvic junction, pelvic brim (where it crosses external iliac), and vesico ureteric junction (just before enters the bladder)
Describe the anatomy of the bladder
Apex, body, fundus, neck
- enters via ureters, exits via urethras
- Trigone = smooth walls
Muscles
- Detrusor - smooth, contracted during mituation
- Internal urethral sphincter - smooth, contracted during filling (closes during male ejaculation)
- External urethral sphincter - skeletal, contracted during filling
Describe the anatomy of the urethra
In women - 4cm long, has two para-urethral mucous glands (Skene’s)
In men - longer, 4 parts
1) Preprostatic part, 1cm contains internal urethral sphincter, smooth muscle
2) Prostatic part, 3-4cm, surounded by prostate gland, contains ridge called urethral crest,
3) Membranous part - contains external urethral sphincter (voluntary)
4) Spongy part - contain within corpus spongiosum (because pressure is lower), forms two bulbous widenings
Describe the anatomy of the prostate (in men)
Prostate lies immediately inferior to the bladder and posterior to the pubic symphysis, surrounding the urethra
-30-40 glands that all discharge into the urethra forming semen
Describe the structure of a nephron - what are the types and their differences
1) Cortical nephron.
Renal corpudcle is further into the cortex.
Henle’s loops do not extend deep into the medulla (sometime they do not have them)
2) Juxtamedullary - about 15% of all nephrons
Renal corpuscle sits near the medullally-cortical junction.
Henle’s loops extend deep into the medulla. (These are responsible for the reabsorption of water by generating an osmotic gradient)
Also have long capillaries that loop deeply into medulla
What are the causes of acute kidney injury?
a) pre-renal
b) post-renal
c) renal
a) pre-renal = severe blood loss and low bp due to major surgery, infection or injury, NSAIDS, ACE inhibitors, severe burns, pancreatitis
b) post-renal = kidney stones in urethras, enlarged prostate, bladder that doesn’t empty properly, blood clots in urethras or ureters, cancer of prostate/cervix/colon
c) renal = glomerulonephritis, acute tubular necrosis
What are the common causes of chronic renal failure?
-Diabetes (1 or 2)
-Obesity
-Hypertension
-Polycystic kidney (genetic)
NSAIDS
What are the major complications of chronic renal failure?
- Fluid retention, lead to swelling and edema (if albumin is lost from the blood)
- Hyperkalemia (K+ isn’t being excreted), can impair heart function
- CVD, increased renin = hypertension = damage heart muscle
- Weak bones (Levels of Ca and phosphorus are abnormal, low Ca = PTH = Ca taken from bones = weaker bones)
- Anemia (kidneys will secrete then erythropoietin if they are damaged, so less RBCs made)
- Damage to CNS (due to urea build up, and others)
Which organs lie retroperitoneally?
S- Suprarenal glands A- Aorta (& IVC) D - Duodenum 2/3 P - Pancreas U - urethra C - colon K - kidneys E - esophagus R - rectum
What is the renal hilum?
Deep fissure - Where the renal vessels and ureter enter/exit the kidney
What is the vasculature of the kidney
- Renal arteries (direct from aorta), distol to superior mesenteric artery
- Each enters via the renal hilum, dividing into segmental branches, they then undergo further divisions to supply the renal parenchyma
- R and L renal veins, empty into IVC
Describe the divisions of the vasculature of the kidneys
- Renal artery (from aorta)
- Segmental arteries
- Interlobar arteries (pass through cortex)
- Arcuate arteries
- Interlobar arteries
- Afferent arterioles = form glomerulus = filtration :)
- Glomerular capillaries
- Efferent arterioles
- Peritubular capillaries
- Interlobular veins
- Arcuate veins
- Interlobar veins
- Renal vein (directly into IVC)
What is the vasculature supply of the ureters
Abdominal = renal artery and testicular/ovarian artery Pelvic = superior and inferior vesical arteries