Fluids and Electrolytes

Question 1

We are ____ % water.

_____ intracellular and _____extracellular.

Answer 1

60%

2/3 and 1/3

Question 2

________ fluid composition is 80% _____ and 20% _____.

Answer 2

Extracellular

interstitial fluid

plasma

Question 3

When managing patient’s fluid status, consider: (4)

Answer 3

• NPO deficit
• maintenance
• evaporative losses and “third spacing”
• blood loss
  *

Question 4

Do not give too much fluid to what patients? (2)

Answer 4

• renal
• CHF (increases preload, which increases contractility, causing cardiogenic pulmonary edema)

Question 5

Hourly maintenance calculation:

Answer 5

4-2-1 rule

or add 40 if weight greater than or equal to 20 kg

Question 6

4-2-1 Rule

Add 4ml/kg/hr for first ___kg

Add 2 ml/kg/hr for second ___kg

Add 1 ml/kg/hr for all weight in excess of 20 kg!

Answer 6

10

10

Question 7

When a wound is large, or when a highly vascular mucosa is exposed during surgery (GI tract or lungs), _____ ___ can be significant.

Minimal tissue trauma (herniorraphy): ___ - ___ ml/kg/hr

Moderate (cholecystectomy): ___-___ ml/kg/hr

Severe (bowel resection): ___-___ ml/kg/hr

Answer 7

• evaporative losses
• 2-4
• 4-6
• 6-8

Question 8

This refers to an internal redistribution of fluids, especially during large thoracic or abdominal procedures.

_______ ____ volume is depleted as inflamed tissue sequesters much fluid in the interstitial space. Replacement of this fluid is necessary to avoid organ hypoperfusion, especially in renal insufficiency.

Answer 8

Third spacing

Intravascular fluid

Question 9

Small lap pads can hold ___ ml of blood.

Large lap pads can hold ____ ml.

Answer 9

10 - 15ml

100 ml

Question 10

Only ___ of the crystalloid will remain in the plasma.

It follows the distribution of ______ _____, most of it passing to the ____ _____.

It cannot pass intracellularly (into the cell) because ions do not cross cell membranes.

Answer 10

• 1/3
• extracellular water
• interstitial fluid/tissue

Question 11

______ are solutions of inorganic and small organic molecules dissolved in water.

The main solute is saline or glucose and the solution may be iso, hypo, or hypertonic.

Answer 11

Crystalloid

Question 12

The following are advantages of_______:

safe, nontoxic, reaction free, and cheap

Answer 12

crystalloid

Question 13

Disadvantages of crystalloid: (2)

Answer 13

• limited time in IV space
• edema with large volumes

Question 14

Half life of crystalloids in IV space is:

Answer 14

30 - 60 minutes

Question 15

In a balanced salt solution of 1000 ml,

• ____ ml will redistribute to the intracellular space
• ___ ml will redistribute into the extracellular space

In extracellular space, ____ will remain intravascular space.

Answer 15

0 ml

1000ml

1/4

Question 16

Normal saline (0.9%) is:

considered ______

_____ mOsm

Answer 16

acidic, pH is 5.5

308 mOsm

Question 17

Lactated Ringers contains what? (5)

Answer 17

• Na
• Cl
• K
• Ca
• Lactate

Question 18

Lactated Ringers

• Acidity is ____
• _____ mOsm

Answer 18

low, pH is 6.5

273

Question 19

Plasma-Lyte components:(4)

Answer 19

• Na
• Cl
• K
• Mg

Question 20

Plasma-Lyte pH is _____.

Answer 20

7.4

Question 21

Saline solution can cause _____ ____ ____.

Answer 21

hyperchloremic metabolic acidosis

Question 22

Lactated Ringers can cause _____ _____

Answer 22

metabolic alkalosis (lactate –> HCO3)

Question 23

Be careful with________containing solutions for renal and hyperkalemic patients.

Answer 23

Potassium

Question 24

Use ____ in neuro cases because it is _____-osmolar and improves the visual field.

Answer 24

Normal saline

hyper

Question 25

The _____ in LR prohibits its use in the presence of blood transfusions.

Answer 25

Calcium

Question 26

Homogeneous noncrystalline substance consisting of large molecules dissolved in a solute. Most are dissolved in normal saline, but glucose, hypertonic saline, and LR have been used as well.

Answer 26

Colloid

Question 27

Advantages of colloid: (3)

Answer 27

• Greater capacity to remain in the IV space (longer half life)
• more efficient for replacing a severe fluid deficit quickly
• smaller infused volume

Question 28

Disadvantages of colloid: (3)

Answer 28

• Greater expense
• coagulopathy
• hypersensitivity reactions

Question 29

Hextend is hetastarch in _____.

Hespan is hetastarch in ____.

Answer 29

LR

NS

Question 30

If we have lost over ___ of the ABL (acceptable blood loss) replace with colloid, especially if the patient is starting to show hemodynamic changes.

Answer 30

1/3

Question 31

What colloid has the longest half life?

However, it can impair ____ function.

Answer 31

Hetastarch

platelet

Question 32

______ __improves microcirculation blood flow by decreasing blood viscosity and is often used by vascular and plastic surgeons to maintain patency of anastamoses.

Answer 32

Dextran 40

Question 33

Dextran (mostly ___), also known as _____decreases platelet aggregation and adhesiveness.

Answer 33

70

Hetastarch

Question 34

Distribution of 1000ml 5% colloid:

___ml in intracellular water

_____ml in extracellular water

Of the extracellular water,

___ ml in extravascular water

___ ml in intravascular water

Answer 34

0

1000

0

1000

Question 35

Know normal lab values:

• Na
• K
• Ca
• Mg
• Cl
• HCO3
• PO4
• SO4

Answer 35

Question 36

___ and water flow together and is the key regulator of water balance in the body.

Its measured value represents ___ rather than total body sodium.

Sodium is the most abundant cation of the ___ ____and is critical in determining the ____ and ____ osmolarity.

Answer 36

• Na
• TBW (total body weight)
• extracellular fluid
• extracellular
• intracellular

Question 37

Hyponatremia occurs when plasma Na < ___ mEq/L

Causes: (3)

Answer 37

135

True loss of sodium (sweating, vomiting, diarrhea, burns, and the administration of diuretics)

Dilutional Hyponatremia: Due to an excess of TBW. This is the most common cause of hyponatremia and is not a deficiency of total body sodium!!

Causes of excess TBW= excess ADH release (stress, SNS activation, SIADH),TURP syndrome.

Question 38

What percent of D5W will go:

intracellularly/extracellularly?

extravascularly/intravascularly?

Answer 38

2/3 intracellularly, 1/3 extracellularly

only 25% will of extracellular will remain in intravascular space

Question 39

No _____ substance crosses into the intracellular space due to the lipophilic cell membrane (unless cotransported).

Answer 39

ionized

Question 40

Hypotonic fluids can promote hyponatremia and have a _______ intravascular half life.

Answer 40

shorter

Question 41

_____ can lead to a reduction in factor VIII and vWf, impairs plt function, and can prolong PTT.

Answer 41

Hetastarch

Question 42

This fluid’s side effects include hypocalcemia allergic reactions < 1% and impaired lung function.

Answer 42

albumin

Question 43

This fluid’s side effects include hypotension (common) and allergic reaction.

Answer 43

plasma protein fraction

Question 44

KEY TERM

What EKG change would you observe in a hypocalcemic patient? (2)

Answer 44

long QT interval changes

heart block