Week 12 - Fluid, Electrolyte and Acid - Base Balance Flashcards
Define extracellular fluid (ECF) and intracellular fluid (ICF)
ECF = Fluid outside cells ICF = Fluid (cytosol) inside cells
Volumes, solute concentrations are stabilised by 3 processes?
fluid balance
electrolyte balance
Acid - Base balance
Define fluid balance
- Daily balance between amount of water gained and water lost to environment
4 fluids in ECF
Lymph
Cerebrospinal fluid
Synovial fluid
serous fluid
4 solute content of ECF
- Electrolytes
- Proteins
- Nutrients
- Wastes
Homestatic mechanisms alter ECF or ICF
ECF
3 primary hormones that regulate fluid and electrolyte balance
- Antidiuretic hormone
- Aldosterone
- Natriuretic peptides
Antidiuretic hormone (ADH) function
- Stimulates water conservation at kidneys
- Stimulates hypothalamic thirst center
Where is ADH released
Hypothalamus
Aldosterone function
Determines rate of sodium reabsorption and calcium loss in kidneys
Where and why is aldosterone secreted
- Secreted by adrenal cortex in response to rising calcium or falling sodium level in blood
Where and why is natriuretic peptides released
- Released by cardiac muscle cells in response to abnormal stretching of heart walls
Natriuretic peptide function
- Reduce thirst
- Block release of ADH and aldosterone
Define Edema (Swelling)
- Movement of abnormal amounts of water from plasma into interstitial fluid
Define lymphedema
- Edema caused by blockage of lymphatic drainage