Fluid, Electrolyte, and Acid-Base Homeostasis Flashcards
Who is at risk of becoming dehydrated?
Infants and children
Older adults
Why are infants and children more at risk of dehydration?
They have relatively small body weights and high turnover of water and electrolytes. Children lose water through evaporation easily.
What are the main functions of fluid?
- Maintain blood volume
- Regulates body temperature
- Transports material to and from the cell
- Serves as aqueous medium for cellular metabolism
- Assists digestion of food through hydrolysis
- Acts as a solvent in which solutes are available for cell function
- Serves as a medium for the excretion of waste
- Consists of fluid contained within all of the billions of cells in the body
- Larger of the two compartments, with approximately two thirds of the body water in healthy adults
- High concentration of K+
Intracellular Compartment (ICF)
- Contains the remaining one third of body water
- Contains all the fluids outside the cells, including that in the interstitial of tissue spaces and blood vessels
- High concentration of Na+
Extracellular Compartment (ECF)
This type of fluid loss can be described as being able to see the fluid output - urine and stool.
Sensible
This type of fluid loss can be described as not being able to see the fluid loss - such as fluid lost through breathing out and evaporation from the skin. (500 - 1000 mL per day)
Insensible
Which body systems are responsible for the most water loss within the body?
The renal and respiratory systems
What are the two types of fluid volume disorders?
Fluid volume deficit (FVD) and Fluid volume excess (FVE)
What are some causes of Fluid Volume Excess?
- Inadequate sodium and water elimination
- Excessive sodium intake in relation to output
- Excessive fluid intake in relation to output
Excessive fluid can be a sign of kidney failure or a cardiac problem
Cardiac symptoms of this syndrome include: bounding pulse, increased pulse rate, jugular vein distention, overdistended hand veins
Respiratory symptoms include: crackles
Fluid Volume Excess
The accumulation of fluid in extracellular space.
The physiologic mechanisms that contribute to this are:
- increase in the capillary filtration pressure
- Decrease in the capillary colloidal osmotic pressure
- Increase in capillary permeability
- Produces obstruction to lymph flow
Edema
This is caused by a problem with fluid return - there is an issue or blockage of the lymph system; usually seen in just one part of the lymph system and affects just one part of the body.
Lymphedema
Accumulation of fluid around the eye.
Periorbital edema
What are the types of edema?
- Localized
- Generalized
- Anasarca: seen in extreme cases
- Dependent
What are the different ways of evaluating edema?
- Pitting edema: leaves indents in the skin that has swelling
- Brawny edema: chronic swelling, skin becomes darker, thicker, and leather-like
- Nonpitting edema
What is the most common cause of fluid volume deficit?
Inadequate fluid intake
What are the causes of fluid volume deficit?
- Inadequate sodium and water retention
- Inadequate sodium intake in relation to output (not likely to occur)
- Inadequate fluid intake in relation to output
Cardiac symptoms of this condition include: increased pulse rate, decreased blood pressure, narrow pulse pressure, slow hand filling, decreased pulse volume
Fluid Volume Deficit
Which electrolytes are most commonly administered via parenteral infusions?
- Sodium (Chloride)
- Potassium
- Calcium
- Magnesium
This electrolyte helps with muscle contractions, nerve signaling, blood clotting, cell division, and forming/maintaining bones and teeth
Calcium
This electrolyte keeps blood pressure levels stable, regulates heart contractions, helps with muscle function
Potassium
This electrolyte is needed for muscle contractions, proper heart rhythms, nerve functioning, bone-building and strength, reducing anxiety, digestion, and keeping a stable protein-fluid balance
Magnesium
This electrolyte helps maintain fluid balance, is needed for muscle contractions, and helps with nerve signaling
Sodium
