Fluid & Electrolytes

Question 1

Distribution of Body Fluid:
Intracellular Fluid (ICF)
Extracellular Fluid (ECF)

Answer 1

ICF: fluid inside the cells (2/3 of body fluid)
ECF: fluid outside the cells (1/3 of body fluid)

Question 2

Extracellular Fluid

Answer 2

Interstitial: surrounds the cells (between cells); includes lymphatic fluid (causes edema if too much fluid)

Question 3

Homeostasis

Answer 3

Balance between ICF & ECF

Question 4

2 Primary Methods of Excreting Fluids

Answer 4

Alimentary Canal (Stool)
Kidneys (Urine)
*Majority of fluids are not excreted by reabsorbed

Question 5

Electrolytes

Answer 5

Substances, when placed in water, have molecules that split into charged particles (ions)

• Cations = positively charged
• Anions = negatively charged

Question 6

Concepts on F & E

Answer 6

Total volume of fluid and total amount of electrolytes in the body are relatively constant
Fluid balance and electrolyte balance are interdependent
Intake must equal output - generally what comes in P.O. comes out as urine
If that doesn’t work then the body will adjust I&O (O greater than I = already balanced and releasing; I greater than O = may have been dehydrated)
Electrolytes are kept in balance based on charge and weight (constantly balancing charge and weight of electron)

Question 7

Osmosis

Answer 7

Movement of fluid through semi-permeable membrane
Goes from a lesser concentration of a solid to a greater concentration of a solid
Pulled by osmotic pressure

Question 8

Electrolytes continued:

Answer 8

Intravascular plasma has a greater amount of protein than interstitial fluid
Why: maintains higher osmotic pressure so the fluid won’t leave

Question 9

Types of IV Fluids: In relation to ICF
Isotonic
Hypotonic
Hypertonic

Answer 9

Isotonic: Same osmotic pressure
Hypotonic: Lower osmotic pressure
Hypertonic: High osmotic pressure

Question 10

Isotonic

Answer 10

Does not change ICF volume
Given to increase intravascular volume
Can help to increase or maintain blood pressure
*Monitor for cardiac overload: cause pt to have too much fluid (fluid volume overload); tachycardia, hypertension, engorged neck veins, crackles
Solutions: Normal Saline and Lactated Ringers

Question 11

Hypotonic

Answer 11

Fluids go from intravascular and interstitial space to the intracellular space
Rehydrates cells (commonly used as flush or enemas)
If too much, cause the cells to lyse (burst)
*Overuse can cause pt to lose Sodium
*Related to GI

Question 12

Hypertonic

Answer 12

Fluid goes from cells to intravascular space
Too much, cause cells to crenate (shrink)
*Albumin = keeps fluid in the vessels
*Monitor for cardiac overload and fluid volume overload

Question 13

Filtration

Answer 13

Movement of fluid through semi-permeable membrane
Goes from high amount of fluid to lower amount of fluid
Pushed by hydrostatic pressure

Question 14

Diffusion

Answer 14

Movement of gas or solid through semi-permeable membrane
Goes from higher concentration to lower concentration
Moves until equal concentration on both sides
Diffusion is important in the transport of most electrolytes and particles through cell membranes

Question 15

Active Transport

Answer 15

Occurs when molecules or ions move against an electrochemical gradient from an are of lesser concentration to a greater concentration (uphill)

Question 16

Dehydration

Answer 16

Fluid intake is less than what is needed to meet the body’s fluid needs, resulting in a fluid volume deficit

Question 17

Fluid Overload

Answer 17

Excess of body fluid
Most problems caused by overhydration in the vascular space or too diluted of specific electrolytes and blood components
*H&H may be down due to diluted serum

Question 18

Sodium

Answer 18

135-145 mmol/L or mEq/L
Reabsorbed by the kidneys via Active Transport
Vital for skeletal muscle contraction, cardiac contraction, nerve impulse transmission, and normal osmolarity and volume of ECF

Question 19

Hyponatremia

Answer 19

<135 mEq/L
Causes:
Renal disease
Increased diaphoresis
Congestive heart failure
Symptoms: 
Cerebral changes
Neuromuscular changes
Intestinal change
Cardiovascular change
Interventions:
Prevent hypernatremia & fluid overload
Diuretic with K+ (Na+ retained when K+ excreted)
Slow salt diet
Fluid restrictions

Question 20

Hypernatremia

Answer 20

>145 mEq/L
Causes:
No enough fluid
High fever
Excessive infusion of hypertonic fluids
Symptoms:
Dry, sticky, mucous membranes
Flushed skin, poor skin turgor - see tenting
Rough, dry tongue
Oliguria/anuria (decreased/no urination)
Interventions:
Drug therapy-fluid replacements

Question 21

Potassium

Answer 21

3.5-5.0 mEq/L
Actively secreted by the kidneys
Depolarization and generation of action potential in nerve conduction, heart conduction, and skeletal muscle contractions
*DO NOT MESS WITH K+ DUE TO THE HEART!

Question 22

Hypokalemia

Answer 22

<3.5 mEq/L
Causes:
Too much non-sparing diuretic
Vomiting, gastric drainage, suctioning
Diarrhea
Symptoms:
Shallow respirations
Weak pulse, arrhythmias, cardiac arrest
Interventions:
Monitor I&O
Evaluate V/S & EKG

Question 23

Hyperkalemia

Answer 23

>5.0mEq/L
Cardiovascular changes: ventricular arrhythmias, arrest, bounding pulse
Neuromuscular changes: muscle weakness, flaccid paralysis with respiratory difficulty
Interventions:
Cardiac monitoring
Hemodialysis
Monitor lab work
Evaluate V/S & EKG

Question 24

Phosphorus

Answer 24

Can be found in the bones (bound with calcium)

Calcium and phosphorus are inversely proportional

Question 25

Calcium

Answer 25

9.0-10.5 mg/dL or 4.5-5.5 mEq/L
Functions closely with phosphorus and magnesium
Absorption requires active form of vit. D
Controlled by 2 hormones: Parathyroid (bones to blood); Calcitonin (blood to bone)
Function:
Need to transmission of nerve impulses (heart and muscle)
Need for blood coagulation

Question 26

Hypocalcemia

Answer 26

s = facial spasm

Question 27

Hypercalcemia

Answer 27

>10.5 mg/dL
Causes:
Hyperparathyroidism
Prolonged immobilization (decreased bone strength)
*High calcium = muscle weakness
Interventions:
IV Saline & diuretics
Phosphate (p.o. or IV)