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PT: Nutrition Exam 2 > Fluids > Flashcards

Flashcards in Fluids Deck (65)
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1
Q

Extracellular fluid compartment

A
  1. Intravascular = fluid component of blood
  2. Interstitial = fluid surrounding cells 3rd spacing
  3. Transcellular = CSF, pericardium, synovial fluid
2
Q

Principal Extracellular Fluid Electrolytes

A

Sodium
Bicarbonate
Chloride

3
Q

Principal Intracellular Fluid Electrolytes

A

Potassium
Magnesium
Calcium

4
Q

Intracellular Fluid (ICF) Calculations

A

2/3 of TBW

5
Q

Extracellular Fluid (ECF) Calculations

A

1/3 of TBW*

a. Interstitial = 3/4 x total ECF
b. Intravascular = 1/4 x total ECF

6
Q

Two factors that regulate total body volume

A
  1. Osmolality

2. Total Body Water

7
Q

Baroreceptors sense change in what compartment of the body for fluid volume regulation?

A

Intravascular

8
Q

T/F: Osmolality always overrides effective blood volume

A

False; Other way! (Think about Edema)

9
Q

Osmolality Critical Values:

A

<260 =

>330 =

10
Q

Must look at both serum [Osm] and ___________ in the patient to assess fluid balance.

A

total fluid volume

11
Q

What can cause a low serum [Osm] but does not indicate excess water in the patient?

A

Loss of electrolytes, especially Na+

12
Q

Hydrostatic pressure pushes fluids ___________ of cell and the interstitial space and ______________ of circulation. Oncotic pressure pushed fluid _________ of cells and the interstitial space and _________ of circulation.

A

Inside; Out

Ouside; Into

13
Q

Hypovolemia

A

Loss of body fluid in the intrastitial and/or intravascular space

14
Q

Two types of hypovolemia:

A
  1. Total body water loss

2. Intravascular hypovolemia - fluid not appropriately distributed

15
Q

Symptoms of Dehydration

A
  1. Rapid weightloss (fluid v fat)
  2. Decreased skin turgor
  3. Oliguria (decreased output)
  4. Concentration urine
  5. Weak, RAPID pulse
  6. Decreased BP (<90/<60), orthostasis (Diastolic drop 10 mmHg; Systolic drops 20 mmHg)
  7. Prolonged capillary filling time - Finger nail bed test
  8. Sensation of thirst, weakness, dizziness, muscle cramps
16
Q

Lab Findings for dehydration

A
  1. High [Osm] due to lots of fluid loss
  2. Low [Osm] due to lots of SODIUM loss
  3. Blood: High HCT, BUN:Cr ratio > 20:1
  4. Urine: High osmolality {>300 mOsm/kg)
17
Q

How do you establish severity of dehydration?

A

Look at weight loss
Mild: 2%
Moderate: 6%
Severe: 10%

18
Q

How do you implement fluid replacement in patients?

A

Must include: Maintenance + Deficit + Ongoing loss

  1. Replace 1/2 of deficit in the first 24 hours
  2. Replace remaining deficit in the next 48 hours
  3. Replace ongoing fluid loss mL/mL
19
Q

What types of fluids can we use for fluid replacement and where do they go?

A
  1. D5W = Intravascular space; Behaves like water (Even distribution)
  2. 1/2 NS = Hypotonic solution acting as 1/2 free water and 1/2 NS in the body
  3. NS = Expands to ECF
  4. 3% sodium chloride
20
Q

Need to increase blood pressure, which fluid replacement option would you use?

a. D5W
b. 1/2 NS
c. NS
d. 3% sodium chloride

A

Normal Saline due to increased fluid to interstitial space

21
Q

Low blood volume and normal sodium content fluid replacement:

a. D5W
b. 1/2 NS
c. NS
d. 3% sodium chloride

A

a. D5W

22
Q

Hypervolemia

A

Thirdspacing of fluid resulting in Edema and Ascities

23
Q

Symptoms of hypervolemia

A
  1. Decreased output
  2. Increased HR
  3. Decreased BP
  4. Rapid Weight increase
  5. Pitting edema: Location, bilateral? and how high
  6. hematoma
24
Q

Bilateral versus Unilateral edema

A
Bilateral = ORGAN FAILURE
Unilateral = some other disease pathway
25
Q

How do we manage hypervolemia?

A
  1. Treat underlying disease
  2. Restrict fluid replacement
  3. Administer diuretics/colloids
26
Q

Best recipient of colloid infusion?

A

Patient with low albumin levels to increase colloid pressure

27
Q

Patient is dehydrated, which fluid replacement should you use to expand volume?

a. D5W
b. 1/2 NS
c. 25% colloid infusion
d. 3% sodium chloride
e. 5% colloid infusion
f. NS

A

e. 5% colloid infusion = iso-oncotic

28
Q

Patient has edema and low albumin levels, which fluid replacement option should you use?

a. D5W
b. 1/2 NS
c. 25% colloid infusion
d. 3% sodium chloride
e. 5% colloid infusion
f. NS

A

c. 25% colloid infusion

29
Q

What defines oliguria?

A

< 400 mL of urine output in 24 H (for adults)

30
Q

What defines orthostasis?

A

> 20 mmHg change in systolic BP with sitting & standing BP
10 mmHg change in diastolic BP with sitting & standing BP

31
Q

Serum Osm when water loss&raquo_space; Na loss

A

Hyperosmolarity > 330 mmol/L (hypovolemia)

32
Q

Serum Osm when water loss &laquo_space;Na loss

A

Hyposmolarity < 260 mmol/L (hypovolemia)

33
Q

What lab values increase with hypovolemia?

A
HCT
Proteins
Electrolytes (sometimes!! Complex...)
BUN: Creatinine > 20:1
Urine osmolality (>300 mOsm/kg, concentrated urine)
34
Q

Mild dehydration (weight loss only, know that symptoms can add urgency)

A

2% weight loss (acute)

35
Q

Moderate dehydration (know that symptoms add urgency)

A

6% weight loss (acute)

36
Q

Severe dehydration (know that symptoms add urgency)

A

10% weight loss (acute)

37
Q

0-10 kg patient fluid needs

A

100 mL/kg

38
Q

10-20 kg patient fluid needs

A

1000 mL + 50 mL/kg over 10

39
Q

> 20 kg patient fluid needs

A

1500 mL + 20 mL/kg over 20

40
Q

Adults fluid needs “rule of thumb”

A

30-35 mL/kg/day

41
Q

Fluid replacement strategy and time line:

A

Day 1: replace 1/2 of the deficit lost in first 24 hours (PLUS MAINTENANCE NEEDS, 1 kg lost = 1 L water)
Day 2/3: replace remaining deficit in the next 48 hours (plus maintenance needs)
Replace ongoing fluid loss mL/mL

42
Q

Cautions in replacing fluid loss with hypovolemic patients:

A
Renal failure
Hepatic failure
Cardiac failure
Elderly
(Pre-disposed to fluid overload, start low and go slow)
43
Q
D5W:
Tonicity
Dextrose content
ECF%
ICF%
Free water/L
A
Hypotonic (no NaCL)
Dextrose 5 g/dL
40% ECF
60% ICF
1 L free water
44
Q
0.45% NaCL:
Tonicity
NaCl mEq/L
ECF%
ICF%
Free water/L
A
Hypotonic
77 mEq/L Na; 77 mEq/L Cl
66.5% ECF
33.5% ICF
0.5 L free water
45
Q
0.9% NaCl:
Tonicity
NaCl mEq/L
ECF%
ICF%
Free water/L
A
Isotonic
154 mEq/L Na; 154 mEq/L Cl
100% ECF
0% ICF
0 L free water
46
Q
3% NaCl:
Tonicity
NaCl mEq/L
%ECF
%ICF
Free water/L
A
Hypertonic
513 mEq/L Na; 513 mEq/L Cl
100% ECF
0% ICF
-2.33 L free water
47
Q
Hypervolemia sign/symptoms:
Urine output
HR
BP
Weight
A
Decreased urine output
Increased HR
Decreased BP
Increased weight
(Edema/ascites/hematoma)
48
Q

Pitting edema scale 1+

A

2 mm (lowest scale)

49
Q

Pitting edema scale 2+

A

4 mm (2nd)

50
Q

Pitting edema scale 3+

A

6 mm (3rd)

51
Q

Pitting edema scale 4+

A

8 mm (4th)

52
Q

Management of hypervolemia (3):

A
  1. Treat underlying disease
  2. Restrict fluids
  3. Diuretics (loop are most effective, thiazides, K+ sparing if underlying disease would make it rational)
  4. Colloids given if proteins v. Low
53
Q

Therapeutic fluids (2) with hypervolemia:

A

Colloid solutions

Oxygen-carrying resuscitation solutions (Blood, PRBC)

54
Q

Albumin 5% indication

Oncotic comparison with plasma

A
Hypovolemic patients (low BP)
Iso-oncotic with plasma
55
Q

25% albumin solution indication

A

Given when fluid intake needs are minimized or oncotic pressure needs are raised (edema)

56
Q

Drug-induced cause from amphotericin B, aminoglycosides (kidney tubule damage), and long-term diuretic therapy

A

Hypomagnesemia (also caused from GI/renal loss and poor intake/absorption)

57
Q

Signs/symptoms of hypomagnesemia usually not seen until

A

< 1 mg/dL

58
Q

S/S: CNS & CV
lethargy, weakness, fatigue, confusion
V-tach, V-fib, premature ventricular contractions

A

Hypomagnesemia (usually not seen until < 1 mg/dL)

59
Q

1 g = ___ mEq Mg

A

8.1 mEq

60
Q

Treatment of hypomagnesemia WITH symptoms AND < 1 mg/dL Mg:

A
  1. IV magnesium sulfate: 2 g bolus

2. Continuous infusion to replenish body stores: 0.5-1 mEq/kg/24 H over 2-5 days

61
Q

Treatment of hypomagnesemia WITHOUT symptoms AND < 1 mg/dL Mg:

A
  1. Continuous infusion ONLY: 0.5-1 mEq/kg/24 H over 2-5 days (to replenish body stores)
62
Q

Treatment of hypomagnesemia without symptoms and Mg > 1 mg/dL:

A
  1. Magnesium oxide supplement: 400-800 mg QID (242 mg of elemental Mg)
63
Q

Seen in renal failure patients taking antacids or laxatives or with excessive doses in hospitalized patients

A

Hypermagnesemia

64
Q

Decreased tendon reflexes
Muscle weakness
Sedation
Vasodilation

A

S/S of hypermagnesemia

65
Q

Treatment of hypermagnesemia (3):

A
  1. DC magnesium source
  2. Ca++ to reverse effects
  3. Administer diuretics to promote excretion