Fluid Imbalances - Checked and Complete Flashcards
What is a typical intake amount of water?
2.5 L
.3 L from oxidation
1 L from food
1.2 L as water
What is usually the foremost danger of electrolyte imbalance?
Hypokalemia
Seen as weakness, fatigue, muscle cramps, potentially heart problems
About what percent of our bodies are water?
Males = 60%
Females = 50%
Based on percentage of Lean Body Mass (no fat included in measurement)
What is the normal ration of ECF to ICF
ECF = 40%
ICF = 60%
How can you figure out the volumes of water in different compartments
Concentration = Quantity/Volume
Administer quantity of tracer, record the concentration, now you know the volume
Why is plasma sodium concentration a good indicator of body fluid osmolarity?
Sodium contributes the most to plasma osmolarity
Demonstrate how to estimate body fluid osmolarity
1) 2 × [Na+] = 90%
2 is to multiply for associated anion concentration
2) Add 10mOsm/L
2 × [Na] + 10 mOsm/L
Demonstrate how to estimate body fluid osmolarity when glucose is abnormally high
10 × ([glucosep] – [normal glucose]p) / 180
Demonstrate how to estimate the total effective osmolar concentration of plasma in mOsm/L
2 × [Na] + 10 + 10 × ([glucosep] – [normal glucosep]) / 180
What are consequences of a low ICF (relatively normal ECF)?
restlessness, irritability, ataxia, spasms, seizures, death (via respiratory failure)
What are symptoms of water excess?
confusion, disorientation, twitching, seizures, coma, death
What do clinical results of water excess/deficit indicate about a patient’s physiology?
Indicates a change to brain neuron fluid/electrolyte balance
Rapid increase/decrease of cranial ICF can compress the brains blood flow or tear blood vessels
Mostly dangerous when change is rapid.
How does mannitol help relieve intracranial pressure after a head injury?
Sets up an osmotic gradient at the blood/brain barrier and draws water out of neurons to decrease intracranial pressure.
How is ICF volume calculated
TBW - ECF
How is an isotonic excess manifest?
Edema in appendages and in lungs
Difficulty breathing because of edema
Probably hypertension
How is an isotonic deficit manifest?
** reduced tissue perfusion**
If happened quickly, then will see increased hematocrit and protein conentration in plasma
How is a hypotonic excess manifest?
Expansion of all fluid compartments, hyponatremia, hypokalemia
Neurological problems because of CNS cellular compartment expansion (compression of cranial arteries)
How is a hypotonic deficit manifest?
Neurological problems because of cranial cell shrinkage, ripping blood vessels between meninges and brain
How does the ISF compare compositionally with the ECF/ICF?
ISF identical to ECF (differences do exist due to extra protein in the plasma but effect is minor; best to compare plasma water; not plasma itself)
Different than ICF
What is the difference between meq/L and mOsm/L?
meq measures charge equivalents, not number of particles
meq can be different with mOsm the same
How do you calculate the TRUE concentration of a plasma solute?
Concentration of solute/PLASMA WATER
