Week 8: Fluids, Electrolytes, and Acid-Base Balance Flashcards
Balance
reflection of overall body function (homeostasis)
Acid Base Balance
- disruption of the balance pH (acid/base) has profound effect on overall health
- outside of the “normal” pH range can lead to death
Body Fluids
- transport gases (CO2 and O2) –> dissolved and transported throughout the body
- make up 60% of body weight
- water content affected by age, sex, and fat cells
- infants = high water content
- decreases with age
Water
-primary body fluid
-content varies with age, sex, adipose tissue (fat cells)
-contains dissolved gases (CO2, O2)
-contains solutes (solid substances)
>electrolytes (sodium, potassium)
>non-electrolytes (glucose, urea)
Electrolytes: Electricity?
- electrolytes develop an electrical charge when dissolved in water
- non-electrolytes do not conduct electricity
Important Function of Bodily Fluids
- maintain blood volume
- regulate body temperature
- transport material to and from cells
- serve as a medium for cellular metabolism
- assist with digesting food
- serve as medium for excreting waste
Body Fluid Compartments
- Intracellular
- Extracellular
Body Fluid Compartments: Intracellular
- within the cells
- essential for cell function and metabolism
Body Fluid Compartments: Extracellular
-Interstitial
-Intravascular
-Transcellular
>outside the cells
>carries water, electrolytes, nutrients, and oxygen to the cells and removes waste products of cellular metabolism
Extracellular: Interstitial Fluid
between body cells
Extracellular: Intravascular Fluid
plasma within the body – transports blood cells
Extracellular: Transcellular Fluid
special fluid such as peritoneal, synovial, pleural, CSF
Third Spacing
-occurs when fluid is “trapped” in a third space
-not within cells or intravascular spaces (blood vessels)
-occurs in illness, trauma, or disease
>pleural effusion (pleural space)
>ascites (peritoneal cavity)
>vesicles (blisters)
Major Electrolytes in Intracellular Fluid?
- potassium
- magnesium
- phosphate
Major Electrolytes in the Extracellular Fluid?
- sodium
- chloride
- bicarbonate
Transcellular fluid –> (gastric + intestinal secretions) – contain electrolytes
Non-electrolyte Present in ECF?
albumin (mostly intravascular)
Electrolyte Imbalances
-when electrolytes move into a compartment not normally occupied
-lost in excessive amounts from body:
>perspiration
>wounds
>injury
>illness
How Do Fluids and Electrolytes Move in the Body?
-passive or active mechanisms across the selectively permeable membranes that separate the ICF and ECF
Passive Transport
requires no energy
- Osmosis
- Diffusion
- Filtration
Active Transport
- requires energy (ATP) to move against a concentration gradient
- occur when molecules (particles such as electrolytes) move across cell membranes from area of low concentration to area of high concentration
- Adenosine triphosphate (ATP) helps in active transport movement
Osmosis
- passive transport
- water moves from less concentration to higher concentration to dilute the higher concentration of solutes
- think of it as if the solute particles are pulling the water over
Diffusion
- passive transport
- molecules from higher to lower concentration
- solute (particles) move through a cell membrane
- movement occurs until concentration is equal on both sides of the membrane