Fluid balance Flashcards
What percentage is solids and liquids of total body mass in men and women?
men:
-40% solids, 60% fluids
women:
-45% solids, 55% fluids
Out of the total body fluids, what percentage is intracellular fluid, and what is extracellular fluid?
intracellular= 67%
extracellular= 33%
What 2 body fluids make up the extracellular fluid portion of the body and at what percentage?
extracellular fluid=
-80% interstitial fluid
-20% blood plasma
What does interstitial fluid include in the body?
-lymph
-CSF
-synovial fluid
-aqueous and vitreous humour
-pleural
-peritoneal
-pericardial fluids
What are the 4 general functions of ions formed when electrolytes break apart?
- control the osmosis of water between fluid compartments
- help maintain acid-base balance
- involved in nerve conduction and muscle contraction
- serve as cofactors for optimal activity of enzymes
Why are ions kept at unequal concentrations across fluid compartments?
to allow osmosis to occur
What does this image show?
Fluid lost from the body is replaced daily, maintaining health, giving an equal fluid balance
Where does fluid mostly enter and exit the body tissues from?
the plasma compartment
What happens when fluid gain exceeds fluid loss?
immediate compensation between compartments may be inadequate to maintain homeostasis
What are the clinical signs of fluid retention or overload?
-weight gain
-hypertension
-oedema
-neurological disturbance
What is oedema and what are the 2 different types?
-oedema results from an excessive accumulation of fluid in the interstitial compartment
- localised oedema= local swelling resulting from injury
- generalised oedema= collection of fluid within the chest cavity, abdomen, or air spaces within the lungs
What happens when fluid loss exceeds fluid gain?
immediate compensation between compartments may be inadequate to maintain homeostasis
What are the clinical sings of dehydration?
-weight loss
-hypotension
-tachycardia
-sticky oral mucus and dry tongue
-low urine production
-neurological disturbances
What happens in capillary exchange?
What is osmosis?
-water passes from a high water potential (less concentrated solution) to a low water potential (more concentrated solution) through a semi-permeable membrane in an attempt to reach equilibrium
What is hydrostatic pressure?
-The pressure exerted by fluid on the walls of a confirming space e.g blood on blood vessel walls
-it reduces as blood passes towards the venous circulation
Explain the role of ADH in maintaining fluid balance
Explain the role of aldosterone in maintaining fluid balance
