Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

sem 2 5043 health and managing disease > week -2: Renal physiology and kidney function > Flashcards

week -2: Renal physiology and kidney function Flashcards

Understand the function of the kidney

1
Q

What are the basic parts of the urinary system?

A
  • 2 x kidneys
  • 2 x ureter (transports urine from kidney to bladder)
  • urinary bladder
  • urethra
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

List the four main domain of functions of the kidneys?

A
  1. Regulatory function
  2. Excretory function
  3. Endocrine function
  4. Metabolic functions
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are the REGULATORY functions of the kidney? Provide examples

A
  • Maintains water balance;

- Maintains electrolyte and acid-base balance :Na, K+, Cl, bicarb, Ca2+, Mg

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What are the EXCRETORY functions of the kidney? Provide examples

A
  • removes metabolic wastes: urea, creatinine
  • excretes bioactive substances: hormones, foreign substances, drugs
  • filters toxins
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are the ENDOCRINE functions of the kidneys? Provide examples

A
  • produce erythropoietin (RBC formation)
  • release renin enzyme (regulates BP)
  • produce prostaglandins: lipid molecules that act like hormones (vasodilation)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What are the METABOLIC functions of the kidneys? Provide examples

A

Aid in activation of vitamin D (alongside the liver)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the functional unit of the kidney known as? What are its major components?

A

Nephron

  1. Glomerulus (cortex)
  2. Tubular system (medulla): proximal tubule, diluting segment, distal tubule, collecting duct
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Describe the flow of blood filtration in relation to vascular structures

A
  1. blood enters kidney from RENAL ARTERIES then through smaller arteries
  2. enters glomerulus via AFFERENT ARTERIOLE
  3. exits glomerulus via EFFERENT arteriole into smaller capillary networks (peritubular capillary)
  4. returns to venous system
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Provide an overview of the steps in urine formation

A
  1. filtration of blood in renal corpuscle
  2. reabsorption of filtered material back to blood to
  3. secretion removes unabsorbed material into filtrate
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What two components should not be filtered out in the glomerulus? Why?

A
  1. blood components: too large to pass through membrane
  2. proteins: proteins are negatively charges and so is the glomerular membrane = repel; so should not end up in ultra-filtrate
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Define the glomerular filtration rate (GFR). What does it indicate? What are the ‘normal’ values

A
  • GFR = estimated rate at which ultra-filtrate is formed in glomerulus
  • indicates renal function
  • Normal is 100 - 200 mL/min
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What factors affect the GFR?

A
  1. cardiac output
  2. BP
  3. vascular volume
  4. SNS tone
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What would happen to the GFR and urine output if BP is suboptimal?

A

Reduced GFR > ↓urine production.

Autoregulation kicks in

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is the feedback mechanism of the kidney GFR called?

A

Autoregulation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Describe the feedback mechanism for when the renal blood flow ( RBF) increases

A

↑RBF = ↑GFR > leads to ↑in NaCl which is detected by macula densa cells > signals the AFFERENT arteriole to ↑ vascular tone > ↓RBF > results in ↓ GFR

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Describe the feedback mechanism if a slow RBF is detected

A

↓RBF > ↓GFR = more reabsorption of substances = less solute in filtrate > Macula densa cells detect ↓ solutes > produce and release (A) renin; (B) kidney also produces prostaglandins > (A) renin acts on angiostensin I to convert to angiotensin II > constricts efferent arteriole; (B) prostaglandins > dilate afferent arteriole

17
Q

What common ailments increases stress to the kidneys?

A
  • CKD: chronic kidney disease
  • DM
  • HTN
  • CCF: congestive cardiac failure
18
Q

Community kidney injury may be caused by taking a cocktail of medications. Provide some examples

A
  • Diuretics
  • ACE inhibitors
  • Furosemide: treats oedema
  • NSAIDs: non steroidal anti-inflammatory drugs
19
Q

What are the reasons for assessing renal function?

A
  1. evaluate state of function
  2. determine extent of kidney disease and advise management plan
  3. determine drug doses: based on kidney clearance
  4. prevent further damage from nephrotoxic agents
20
Q

Provide an example of what EXOGENOUS filtration marker is used to measure GFR

A

Insulin

21
Q

List 2 ENDOGENOUS markers are used to estimate GFR?

A
  • serum Creatinine

- Urea

22
Q

for Urea:

  1. what is it?
  2. what happens to it in the kidney
  3. is it a sensitive marker for renal function?
  4. what are the reference intervals?
A
  1. End product of protein and amino acid catabolism
  2. filtered at glomerulus, 40-60% reabsorbed
  3. INsensitive - usually measured w. serum creatinine
  4. neonates 1-4 mmol/L; adults 3-8 mmol/L
23
Q

for serum Creatinine:

  1. what is it?
  2. what happens to it in the kidney
  3. is it a sensitive marker for renal function?
  4. why is it used as a marker?
  5. what are the reference intervals for M & F?
A
  1. waste product of muscle metabolism in liver (breakdown of creatine)
  2. 90% excreted by kidney via glomerular filtration
  3. more sensitive than urea but should not the sole measure
  4. sCr is inversely proportional to GFR
  5. M: 60-12; F: 50-110 umol/L
24
Q

What does a high number sCR indicate about the kidney function?
What would a doubling of the sCr indicate about renal function?

A
  1. poor kidney function - not being filtered out

2. represents a 50% reduction in refunction

25
Q

What factors may influence sCr and what are the expected effect on sCr levels?

A
  • age: ↓
  • female:↓
  • African American: ↑
  • vegetarian: ↓
  • muscle mass: ↑
  • malnutrition: ↓
26
Q

List 3 alternative methods to estimating renal function?

A
  • Creatinine Clearance (>50 mL/min)
  • eGFR (> 90 mL/min)
  • Protein and albumin
27
Q

Provide example of drugs that should have creatinine clearance calculations done for dosing

A
  • metformin
  • digoxin
  • atenolol
28
Q

Creatinine clearance can indicate grades of renal impairment. What are the rates for mild, moderate and severe states?

A

Mild: 25-50 mL/min
Moderate: 10-25 mL/min
Severe: <10 mL/min

29
Q

What is urinary protein/albumin (ACR) used to characterise?

A

Severity of CKD

Also indicates increased cardiovascular risk

30
Q

What factors are known to increase albuminuria?

A
  • UTI
  • High protein intake
  • CCF : congestive cardiac failure
  • heavy exercise
  • Drugs: NSAIDs

sem 2 5043 health and managing disease (3 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions