Brainscape's Knowledge GenomeTM

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


See full index

MD4001 Physiology > Fluid and Electrolyte balance > Flashcards

Fluid and Electrolyte balance Flashcards

1
Q

IV glucose (5%) is mostly distributed where in the body?

A

Mostly intracellularly

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

Colloid fluid will be distributed where in the body?

A

Plasma (will not pass through semi-permeable membrane)

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

Saline will mostly be distributed where in the body?

A

Extracellularly (mostly interstium)

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

What percentage of body weight is water?

A

60%

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

How is body water distributed in an average 70kg male (42L)?

A

Intracellular 28L
Extracellular 14L
- Interstitium 11L
- Plasma 3L

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

What is the barrier between plasma and interstitium?

A

Capillary wall

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

What is the barrier between extracellular fluid and intracellular fluid?

A

Plasma membrane

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

Where is K+ mostly located?

A

Intracellularly

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

Where is Na+ mostly located?

A

Extracellularly

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

Where is Mg2+ mostly located?

A

Intracellularly

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

Where is Cl- mostly located?

A

Extracellularly

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

Where do negative charges come from pricipally inside the cell?

A

Proteins and phosphate

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

Where does the body lose fluid?

A
  • Urine - 1500ml
  • Faeces - 100ml
  • Sweat ~ 50ml
  • Insensible losses - 900ml
    Total = 2550ml
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

How much urine ouptut is expected per hour?

A

0.5 ml / kg / hour

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

How much more fluid is lost per degree rise in a fever?

A

500ml per 24 hours per degree rise

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

Where can insensible water loss be from?

A
  • Transdermal diffusion
  • Evaporative loss from respiratory tract
    They are solute free
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is insensible water loss replaced with?

A

High percent dextrose

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

What are the sensors of body fluid?

A
  • Osmoreceptors in hypothalamus
  • Low pressure baroreceptors in Right Atria and great veins
  • High pressure sensors (carotid sinus / aorta)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What do osmoreceptors in the hypothalamus stimulate?

A
  • Thirst

- ADH (decreases output)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What does an increase in osmolarity lead to?

A
  • Increase in thirst
  • Increase in release of ADH
  • Increase in water intake/retention
  • Increase in volume
    Opposites for a decrease in osmolarity
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What disease is an increase in blood volume associated with?

A

Heart Failure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What does an increase in blood volume lead to?

A
  • Baroreceptors sense
  • Decreased renin release
  • Decreased aldosterone release
  • Increased release of ANP (cardiac myocytes)
  • Decreased Na+ and water retention
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What does a decrease in blood volume lead to?

A
  • Baroreceptors sense
  • Pressure fall causes ADH release and thirst
  • Increased renin release
  • Increased levels of Angiotensin II
  • Increased aldosterone release
  • Decreased release of ANP
  • Increased Na+ and water retention
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What receptors are associated with day to day changes in blood volume?

A

Osmoreceptors in hypothalamus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

If Na+ drops and osmolarity (tightly regulated) stays the same what happens to total volume?

A

Total volume (including plasma volume) decreases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Where is the area for controlling Na+ balance?

A

DCT in the nephron

27
Q

What are Na+ levels controlled indirectly by?

A

Volume receptors

28
Q

What is net Na+ excretion determined via?

A

Na+ filtered - Na+ reabsorbed

29
Q

How do humans gain K+?

A

Through food / drink

30
Q

Where is K+ lost?

A
  • Urine (mostly)

- Sweat and faeces

31
Q

Where is K+ reabsorbed in the nephron?

32
Q

WHere is K+ secreted?

A

DCT (controlled secretion)

33
Q

What pump is secretion of K+ linked to?

A

Na/K+ ATPase (so Na+ is reabsorbed)

34
Q

What hormone changes the apical ion channels and the Na+/K+ exchanger basolaterally?

A

Aldosterone

35
Q

What percentag of K+ is contained inside cells?

36
Q

What are the effects of increased K+ in plasma?

A
  • Increases activity of basolateral Na+ pump
  • More K+ enters cell
  • Increased secretion across simple diffusion channels on apical membrane
  • Increased secretion of aldosterone
  • NOT driven by all, but by direct detection of raised K+ levels by the aldosterone-secreting cells of the adrenal cortex
37
Q

What are the effects of aldosterone on the DCT?

A
  • Increases activity of sodium pump (basolateral)
  • Increaes the number of sodium pumps (basolateral)
  • Increases the number of sodium and potassium channels in apical membrane
  • Result: increased reabsorption of sodium and increased secretion of potassium
38
Q

What is Conn’s syndrome?

A

Hyperaldosteronism leading to hypertension from increased flui volume and hypokalaemia

39
Q

What are risks associated with IV fluids?

A
  • PVC required (peripheral venous catheter)
  • Easy to give too much fluid
  • Errors in prescribing
  • Infection risk
40
Q

What is required in a history before diagnosing IV fluids (what factors should be considered)?

A
  • Limited intake?
  • Abnormal losses (how much, what kind of fluid e.g ion rich, ongoing, can you treat the cause)
  • Comorbidities?
  • Current illness?
  • Symptomatic?
  • Fluid balance charts
41
Q

What [vital] signs are suggestive of hypovolaemia?

A
  • Systolic BP <100mmHg
  • HR > 90
  • Capillary refill > 2 secs
  • Resp Rate 20 breaths/min
  • Urine output < 0.5 mls/kg/hr
  • Dry mucous membranes
  • Decreased skin turgor
  • Responsiveness to passive leg raising (45th)
  • Postural hypotension
  • Weight
42
Q

What signs are indicative of fluid overload?

A
  • History of cardiac or renal problems
  • Raised JVP
  • Peripheral oedema
  • Inspiratory crackles at lung bases
  • Hypertension
43
Q

What investigations are helpful when diagnosing hyper or hypovolemai?

A
  • FBC
  • UsandEs
  • CXR
  • Lactate
  • Urine biochemistry
44
Q

What are maintenance fluids?

A

Regular fluids which are used if an individual has no abnormal losses (0.18% Na/Cl 4% dextrose)

45
Q

What are replacement fluids?

A

Used to replace abnormal fluid loss used in addition to maintenance fluids

46
Q

What are resuscitation fluids?

A

Patient is hypovolaemic and requires urgent correction of intravascualr depletion (bolus)

47
Q

what does the colour of a peripheral venous catheter indicate?

A

The size (smallest yellow largest orange) (most used pink and green)

48
Q

What is the most common infection associated with peripheral venous catheterisation

A

Staph aureus (should be inspected everyday)

49
Q

How often should a peripheral venous catheter be changed? (unless good reason not to)

50
Q

What is 5% dextrose similar to?

A

Adding water

51
Q

What is the composition of maintenance fluid?

A
  • 0.18% NaCl

- 4% dextrose

52
Q

What is the composition of isotonic saline? (used when someone is losing ion rich fluid)

A
  1. 9% NaCl (isotonic saline)

- Also fluids of choice in ressucitation

53
Q

What are different examples of colloid fluids?

A
  • 4.5% albumin (with 0.9% NaC)
  • Hydrolysed gelatin (with 0.9% NaC)
  • Blood
54
Q

What is the main risk factor of IV colloids?

A

Anaphylaxis

55
Q

Where is caution required when administering IV fluids?

A
  • Obese patients
  • Elderly or frail
  • Renal impairment
  • Cardiac failure
  • Malnourished or at risk of refeeding syndrome
56
Q

What does a Central Venous Pressure line measure?

A

Right Atrial Pressure

57
Q

What is the target Right atrial pressure (CVP line)?

A

8 - 12 mmHg

58
Q

What are the principles involved in managing DKA pateints?

A

ACT RAPID

  • Airway, breathing, circulation
  • Commence fluid resuscitation
  • Treat K+
  • Replace insulin
  • Acidosis management
  • Prevent complications (vulnerable to cerebral oedema)
  • Information for patients
  • Discharge
59
Q

What are the features of Diabetic Ketoacidosis (DKA)?

A 
Hyperglycaemia 
- Dehydration 
- Tachycardia 
- Hypotension 
- Clouding of consciousness 
Acidosis 
- Air hunger (kussmaul's respiration)
- Acetone on breath 
- Abdominal pain 
- Vomitting

SEPSIS features

60
Q

What fluids are given to treat DKA?

A
  • 1L of 0.9% saline in first hour
  • Insulin 6 UNITS / hour
  • K+ may be low or high - needs K+ IV slowly
61
Q

At what levels of K+ is insulin and/or K+ prescribed?

A

K+ < 3.3 mmol/L

  • 20-30 mmol K+/hour
  • Hold insulin

K+ 3.3-5.3 mmol/L

  • 20-30 mmol K+/hour per L of IV fluid to keep Serum K+ between 4-5 mmol/L
  • Insulin

K+ > 5.3 mmol/L

  • K+ not given but checked every 2 hours
  • Insulin
62
Q

What are K+ levels expected to be in the region of?

A

4 - 5 mmol/L when treating DKA

63
Q

Why is an ECG required when treating DKA?

A

High K+ as a result of DKA can cause cardiac arrhythmias

MD4001 Physiology (22 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions