Fluid Therapy And Replacement Flashcards
(72 cards)
1
Q
4 things that rate depends on:
A
- Permeability of substance
- Concentration differences
- Pressure differences
- Electrical potential
2
Q
Net movement of water across a semipermeable membrane due to a difference in solute concentrations
A
Osmosis
3
Q
Number of osmoles/liter
A
Osmolarity
4
Q
Number of osmoles/kilogram of water
A
Osmolality
5
Q
Normal human serum osmolality
A
275-299 miliosmoles/kilogram
6
Q
Total body water
A
60% of body weight, 42L
7
Q
Intracellular fluid
A
67% of TBW, 28L
8
Q
Extracellular fluid
A
33% of TBW, 14L
9
Q
Interstitial fluid
A
25% of TBW, 11L
10
Q
Plasma fluid (intravascular)
A
8% of TBW, 3L
11
Q
Volume of water in males
A
60%
12
Q
Volume of water in females
A
50-55%
13
Q
Volume of water in newborns
A
75%
14
Q
Volume of water in obese patients
A
As low as 45%
15
Q
Intracellular fluid body compartment (4)
A
- Comprises 2/3 of TBW
- Osmotic pressure determined by K+
- High protein content
- Controlled by ATP pump
16
Q
Extracellular fluid body compartment (3)
A
- Comprises 1/3 of TBW
- Osmotic pressure determined by Na+
- Subdivided into interstitial and intravascular (plasma)
17
Q
Interstitial extracellular fluid compartment (2)
A
- Very little free fluid
2. Reservoir for intravascular compartment
18
Q
Intravascular extracellular fluid compartment (3)
A
- Restricted by vascular endothelium
- Electrolytes pass freely
- Plasma proteins usable to pass (albumin)
19
Q
Crystalloids (3)
A
- Aqueous solutions of ions (glucose)
- IV half life is only 20-30min
- Large volumes cause edema
20
Q
Movement of water in hypotonic fluids
A
Water will move intracellularly
-decreases IV volume
21
Q
Hypotonic fluids osmolarity
A
<240 MOSM/L
22
Q
Uses of hypotonic fluids (3)
A
- Hypernatremia
- Diabetic ketoacidosis
- Hyperosmlar/hyperglycemia
23
Q
4 risks of hypotonic fluids
A
- Increase ICP
- Worsens hypotension
- Hyperglycemia
- Hemolysis
24
Q
Water movement of hypertonic fluids
A
Mostly remains in ECF
-pulls from ICF
25
Osmolarity of hypertonic fluid
>310 MOSM/L
26
2 uses for hypertonic fluid
1. Plasma expanders
| 2. Reduce cerebral edema
27
4 risks of hypertonic fluids
1. Hyperchloremic metabolic acidosis
2. Pulmonary edema
3. IV infiltration
4. Cellular dehydration
28
Serum osmolality of isotonic fluids
275-299 MOSM/KG
29
Use of isotonic fluids
Replace extracellular volume
30
Risk of isotonic fluids
Fluid overload (caution in cardiac/renal pts)
31
2 things that lactated ringers has:
Potassium and calcium
32
3 cautions with lactated ringers
1. Renal pts
2. Hyperkalemia pts
3. Do NOT use with blood administration
33
Osmolarity of normal saline
308 MOSM/KG
34
When is normal saline preferred?
Renal pts
Brain injury
Blood administration
35
What can large volumes of normal saline cause?
Hyperchloremic metabolic acidosis
36
What does colloids contain?
Proteins and large glucose polymers
37
Intravascular half life of colloids
3-6hrs
38
Two types of albumin
5% (iso-oncotic)
| 25% (hyper-oncotic)
39
How long do effects of albumin last?
16-24hrs
40
What 2 types of dextran’s are there?
```
Dextran 70 (macrodex): molecular wt 70,000
Dextran 40 (rheomacrodex): molecular wt 40,000
```
41
3 complications of dextran:
1. Anti platelet effects
2. Acute kidney injury
3. Anaphylactic rxns
42
Synthetic colloid derived from natural polysaccharides
Hydroxyethyl starches (HES)
43
Duration of volume with hydroxyethyl starches
2-5hrs
44
3 complications with hydroxyethyl starches
1. Pruritus from tissue storage
2. Coagulopathy
3. Renal toxicity
45
4 signs of laboratory analysis
1. Increasing HCT/HB
2. Hypernatremia
3. BUN: CR ratio > 10:1
4. Progressive metabolic acidosis
46
7 signs of intraop hypovolemia
1. Tachycardia
2. Poor urine output
3. Decreased BP
4. Wavering pulse ox
5. Arterial line respiratory variation
6. Hypernatremia
7. Decreased CVP
47
5 signs of intraop hypervolemia
1. Rales
2. Frothy secretions
3. Hyponatremia
4. Polyuria
5. Peripheral edema
48
- BP
- HR
- Urine Output
- Central Venous Pressure (CVP)
- Mixed venous oxygen saturation
Static parameters
49
- Respiratory variation
- SV
- L ventricular size
Dynamic parameters
50
CVP RA normal pressure
2-7mmHg
51
SVV equation
SVmax-SVmin/SVmean
52
Normal SVV
10-15%
53
PPV equation
PPmax-PPmin/PPmean
54
Normal PPV
10-15%
55
What SVV or PPV suggests that pts may be responsive to fluid therapy?
>15%
56
Arterial pressure tracing estimates:
CO
PP
SV variation with ventilation
57
2 ways to perform L ventricular size:
```
Transesophageal echocardiography (TEE)
Transthoracic echocardiography (TTE)
```
58
TEE
Invasive
| Better visualization
59
TTE
Less invasive
| Visualization harder
60
Daily maintenance requirements
2500ml/day
61
4 replaces fluids
1. Maintenance requirements
2. Deficits
3. Estimated Blood loss
4. Other surgical fluid losses
62
4-2-1
First 10kg - 4ml/kg/hr
Next 10kg - 2ml/kg/hr
Each kg above 20 - 1ml/kg/hr
63
Bowel prep deficit
500ml
64
4x4 sponges holds blood loss
10ml
65
Laparotomy pads (laps) holds blood loss
100-150ml
66
Replacement of EBL:crystalloid
1:3
67
Replacement of EBL:colloid
1:1
68
Surgical evaporative loses minimal
2-4 ml/kg/hr
69
Surgical evaporative loses moderate
4-6 ml/kg/hr
70
Surgical evaporative loses severe
6-8 ml/kg/hr
71
Internal redistribution of fluid leading to fluid shifts and loss of IV fluid
3rd space fluid loss
72
Replacement of preexisting fluid deficits over 3 hr
1/2 deficit in 1st hr
1/4 deficit in 2nd hr
1/4 deficit in 3rd hr
