Fluid Imbalance Flashcards
Fluid balance?
equilibrium in water exchange between internal fluid compartments of the body and between the body and the external environment
hypovolemia
Low blood volume
- extracellular volume depletion
- water and electrolytes lost in same proportion
Etiology for Hypovolemia
a. Decrease in intake of fluids = dehydration oral or Iv fluids
b. Decrease in extracellular volume = loss of blood, vomiting, diarrhea, excess swelling
pathophysiology for hypovalemia
decreased blood volume
= decreased Capillary hydrostatic pressure and filtration
- cells deprived of substances that they need to function
clinical manifestations of hypovalemia?
- Tissue dehydration (tenting, dry mucus membrane)
- decreased blood volume = decreased BP, decreased urine output, and increased heart rate
- Decreased tissue perfusion = decreased 02 supply in blood
Hypervolemia
increased blood volume
- Excess extracellular fluid
- Water and electrolytes gained in the same proportion
Hypervolemia etiology (caused by)
increased administeration of isotonic fluids
- increased dietary intake of NaCl (pulls h2O with it)
- diseases: chronic renal failure, heart failure and liver failure hyperaldosteronism (RAAS system)
- Expansion of extracellular space and circulatory overload = because an increase in volume
Hypervolemia clinical manifestations
- Edema = swelling of tissues
- Increased BP and bounding pulse = opposite of hypovolemia, lot of fluid causes paulse
- Urine output ↑
- Weight gain (edema)
- Shortness of breath = if around alveoli in lungs
Edema
expansion or accumulation of interstitial fluid volume (third space shift)
- Fluid shifts from plasma (intravascular) to interstitial spaces
Edema Etiology or caused by
- inflammation
- increased BV
- venous obstruction
- decreased serum albumin
Edema pathophysiology
- Increased capillary permeability
- decreased capillary osmotic pressure (pulls fluid back in)
- increased capillary hydrostatic pressure (pushes fluid to tissue)
- Lymphatic obstruction (lymph cannot absorb fluid)
Edema clinical manifestations
Pitting = depression
weeping = seeping through damaged skin
Dependent = body part on a dependent position (not using Atm)
generaized = edema all over (kindey failure)
Pulmonary = edema in the lungs (heart failure)
2 types of osmolar imbalances?
Hypotonic (hypo-osmolar Imbalance)
Hypertonic (hyperosmolar Imbalance)
Hypotonic?
Excess retention of free water or low solute intoxication
Hypotonic Etiology
- Excess water intake
- End stage renal failure = kidney cant excrete water
- Inappropriate ADH release
Hypotonic pathophysiology
- Movement of water to intravascular space and into cells
- cellular swelling
Hypotonic clinical manifestations
- Decreased serum osmolarity
- decreased hematocrit (diluted blood)
- low urine specific (gravity urine is diluted)
- central nervous system changes = headache, confusion because cells swell in brain
Hypertonic (hyperosmolar imbalance)
excess concentration of extracellular fluid (water deficit, blood is concentrated)
Hypertonic Etiology
- Decreased water intake
- Insufficient intake of free water
- increased loss of free water
- excess intake of hypertonic solutions
Hypertonic pathophysiology
Hypertonic extracellular fluid environment
- shrinkage of cells
hypertonic cellular manifestations
- Elevated serum osmolarity
- increased hematocrit (concentration of blood)
- high urine specific gravity (more concentrated urine)
- Tissue dehydration
- polydipsia (more thirsty)
- central nervous system changes: confusion from h20 being pulled out of the brain because they are dehydrated
