Brainscape's Knowledge GenomeTM

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


See full index

Renal > Acid base balance > Flashcards

Acid base balance Flashcards

1
Q

What is the normal pH of arterial blood?

A

7.45

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

What is the normal pH of venous blood?

A

7.35

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

What can acidosis lead to?

A

CNS depression

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

What can alkalosis lead to?

A

Over excitation of PNS and CNS

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

What generates H+ in the body?

A

Metabolism

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the difference between a strong and weak acid?

A

Strong acid dissociates fully in solution

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

What is a buffer system?

A

Two substances of which one can absorb free H+ and one can donate it

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What happens if more H+ is added to a system?

A

A- mops it up to generate more HA (conjugate acid). Buffering.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What happens if more base is added to a system?

A

More HA dissociates leading to an increase in H+. Buffering.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

How do you calculate the pH of a substance?

A

pK + log[A-]/{HA]. [A-]=base, [HA]=acid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is the most important physiological buffer system?

A

CO2-HCO3 buffer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Describe the CO2-HCO3 buffer system

A

H2O+CO2 H2CO3 H+ + HCO3-

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is the acid and base in the CO2-HCO3 buffer system?

A

Acid- H2CO3

Base- HCO3-

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

What role do the kidneys play in the CO2-HCO3 buffer system?

A

Variable reabsorption of HCO3

Add new HCO3 to the system

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

How is HCO3 reabsorbed at the luminal membrane?

A

Changed back to H2O and CO2 then reabsorbed.

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

What happens to HCO3 once it’s in the epithelial cells?

A

Converted from H2O and CO2 back to HCO3

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

How does HCO3 get out of the epithelial cells?

A

NaHCO3 cotransporter.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

How can the kidneys generate more HCO3?

A

By allowing free H+ to combine with phosphate and being excreted when HCO3 is low thus allowing excretion of H+ without HCO3 loss.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

How much acid is excreted a day combined with phosphate?

A

40mmol/day

20
Q

What other molecule can be used as a buffer for H+?

A

Ammonia

21
Q

What parameters need to be filled for someone to be near normal acid base balance?

A

Plasma pH close to 7.4 (7.35-7.45)
HCO3- close to 25mmol/l (23-27)
Arterial pCO2 close to 40mmHg (35-45)

22
Q

What is the difference between compensation and correction?

A

Compensation- restore pH to 7.4 at detriment of HCO3 and pCO2
Correction- Restore all three to normal

23
Q

What are the four disturbances that can affect the acid-base balance?

A

Resp acidosis
Resp alkalosis
Met acidosis
Met alkalosis

24
Q

What is immediate buffering?

A

Buffering of change immediately with HCO3 in the blood etc.

25
Q

How long can immediate buffering last for?

A

Not very long

26
Q

What can cause resp acidosis?

A

Retention of CO2 in the lungs

27
Q

What happens in resp acidosis?

A

Equal increase in H+ and HCO3-

28
Q

What indicates uncompensated resp acidosis?

A

pH<7.35 and pCO2>45

29
Q

How is resp acidosis compensated for?

A

Excretion of H+ with P in urine and all HCO3 reabsorbed

30
Q

What causes resp alkalosis?

A

Excessive removal of CO2

31
Q

What happens in resp alkalosis?

A

Both H+ and HCO3 fall

32
Q

What indicated uncompensated resp alkalosis?

A

pH>7.4 and pCO2<35

33
Q

How is resp alkalosis compensated for?

A

Decreased H+ secretion and increased HCO3 secretion

34
Q

What causes met acidosis?

A

Excessive H+ from any source other than resp:
Exercise (lactic acid)
Loss of base (diarrhoea)

35
Q

What indicated uncompensated met acidosis?

A

pH<7.35 and HCO3 very low

36
Q

How is met acidosis compensated for?

A

Increase ventilation which removes CO2 thus losing H+ and HCO3. HCO3 reabsorbed from urine and H+ secreted to produce new HCO3.

37
Q

What causes met alkalosis?

A

Hacessive loss of H+ from the body:
Vomiting
Aldosterone hypersecretion

38
Q

What indicated met alkalosis?

A

pH>7.45 and HCO3 very high

39
Q

How is met alkalosis compensated for?

A

Ventilation decreased giving rise to both H+ and HCO3. Lots of HCO3 filtered and most not reabsorbed.

40
Q

How long does extracellular buffering of H+ take to start working in met disturbances?

A

Immediatly

41
Q

How long does resp buffering of H+ start to take working in met disturbances?

A

Minutes

42
Q

How long does intracellular buffering (proteins etc) of H+ start to take working in met disturbances?

A

2-4 hours

43
Q

How long does renal buffering of H+ take to start working in met disturbances?

A

Days-weeks

44
Q

How long does extracellular buffering take to start to start working in resp disturbances?

A

Immediately but not very effective.

45
Q

How long does renal buffering take to start working in resp disturbances?

A

Hours to days

Renal (13 decks)

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