FLUID & ELECTROLYTE BALANCE

Question 1

WATER CONTENT

Answer 1

-Water is the most abundant compound in the body
-Makes up 60% of body weight in males, 50% in females
-Average volume is 40L in a 70kg male.

-Varies based on:
Total body weight
Fat content (more fat = less water)
Gender (females have 10% less than males)
Age (newborns-80%, decreases in older adults)

Question 2

Extracellular Fluid (ECF) -15L

Answer 2

-Forms the body’s internal environment

-Surrounds cells and transports substances

-Three types:
o Plasma: Liquid part of blood.
o Interstitial Fluid: Surrounds cells.
o Transcellular Fluid: Includes cerebrospinal, synovial, and joint fluids.

Question 3

Intracellular Fluid (ICF) -25L

Answer 3

o Largest fluid compartment
o Located within cells
o Serves as a solvent to facilitate intracellular chemical reaction

Question 4

Fluid Balance Mechanisms

Answer 4

o Intake:
- Driven by thirst mechanism (regulated by the hypothalamus).
- Sensory receptors detect dry mouth or high osmolality.

o Output:
- Regulated by:
- ADH: Promotes water reabsorption in kidneys.
- Aldosterone: Retains sodium and water.
- ANH: Promotes sodium and water excretion.

Question 5

Regulation of Fluid Input

Answer 5

o ECF electrolyte concentration affects volume
o Hypothalamus controls thirst response
o Decreased saliva triggers drinking behavior

Question 6

Fluid Exchange

Answer 6

• Capillary blood pressure pushes water into interstitial fluid.
  • Plasma proteins pull water back into blood vessels.

Question 7

Fluid Assessment

Answer 7

• Blood pressure (BP): Low BP indicates dehydration.
• Skin turgor: Decreased elasticity signals dehydration.
• Edema: Indicates overhydration or fluid shift.
• Urine Specific Gravity:
  o Normal: 1.010–1.035.
  o Low: Diluted urine (overhydration).
  o High: Concentrated urine (dehydration).
• Daily weights: Track fluid retention or loss.
• Intake & output monitoring
• Thirst levels

Question 8

Electrolytes, Functions & Imbalances

Answer 8

Question 9

Anions

Answer 9

Question 10

Fluid Imbalances

Answer 10

Question 11

Cell Transport Methods

Answer 11

Passive Transport
* Diffusion
* Osmosis
* Filtration

Active Transport
* Ion pump (moves ions against the concentration gradient)