Fluid Acid - Base Balance Flashcards
Edema
- is a manifestation
- palpable swelling produced by expansion of interstitial fluid volume
- increase fluid volume in interstitial space from vascular space
Physiologic mechanisms that contribute to edema
- increase in hydrostatic pressure
- decrease in colliod osmotic pressure
- increase in capillary permeability
- obstruction of lymph flow
Hydrostatic pressure is always
push pressure
Osmotic pressure is always
pull pressure
Dehydration
- volume deficit
- decrease in interstitial fluids and intravascular fluids
causes of dehydration:
- inadequate intake
- loss to 3rd space
- excessive gastrointestinal fluid, renal or skin losses
Ph is the measurement of
Hydrogen ion concentration
Ph changes alters
enzymes, proteins & metabolism
4 types of imbalances
- respiratory acidosis/alkalosis
- metabolic acidosis/alkalosis
Normal Ph maintained by
- Buffers
- Lungs - Exhalation of C02
- Kidneys
- excretion of H+
- re absorption of HC03
important buffer
carbonic acid buffer
carbonic acid is
volatile, unstable, dissociates as soon as it is formed
respiratory acidosis involves ___ acid
Carbonic acid (volatile acid)
metabolic acidosis involves ___
other acids, fixed acids (ex. lactic acid)
if lungs are working properly should not have
C02 imbalance
3rd space loss
- fluid accumulates in transcellular space (not easy to remove/reverse)
- not easily exchangeable
- loss to 3rd spacing ex. fluid in abdominal cavity, joint
- fluid moves into an area that is not usually involved in fluid exchange
Kidneys & lungs can _______ for each other when 1 malfunctions
compensate
enzymes have narrow PH ranges which may cause them to be
denatured via incorrect ph
causing them not being able to drive reactions or functions cannot occur
acid-base balance is measured by
ABGS (arterial blood gases)
normal Ph of extracellular fluid is
7.35-7.45
normal Ph of blood is
7.4
Ph of patient refers to Ph of
blood (unless otherwise stated)
respiratory imbalance
- carbonic acid related
- relates to C02 (build up of too much or too much exhaled)
lungs and kidneys can compensate for each other to
normalize the ph
metabolic acidosis
too much acid or decreased base
metabolic alkalosis
too much base or decreased acid
Treatment of acid/base imbalance
- oral or IV replenishment of fluid that neutralizes issue (adjust ph)
- FIRST fix underlying cause
respiratory acidosis
impaired ventilation (decrease in ventilation) –increase in PC02 —– decrease in Ph (resp acidosis)
respiratory alkalosis
hyperventilation (increase elimination of C02 – decrease in PC02 — increase in Ph (respiratory alkalosis
impaired ventilation causes
respiratory acidosis
hyperventilation causes
respiratory alkalosis
impaired ventilation _____ C02
increases
hyperventilation _____ C02
decreases
