Fluid and Electrolytes Lecture Powerpoint Flashcards
Literally kill me now
Total body water (TBW) definition
The summation of all the different forms of water in the body, approx 60% of body weight in males and 50% in females
Intracellular fluid definition
Summation of fluid that lies intracellularly in the body, composes 40% of total body weight or 2/3 of total body water
Extracellular fluid definition
Summation of fluid that lies extracellularly in the body, composes 20% of total body weight or 1/3 of total body water
Intravascular space definition
Summation of fluid that lies within the vessels as part of extracellular fluid and composes 25% of extra cellular fluid or 5% of total body weight
Interstitial space definition
Summation of fluid that lies within the body between cells as part of extracelluar fluid and compses 75% of extracellular flulid or 15% of body weight
Osmosis definition
Movement of water from low solute conc. to higher solute conc. passively to attain equilibirrum
Total body water is directly related to ___ and inversely related to ____. Infants, for example…
Lean body mass, fat content
…have higher percentage of body water because not as much fat
In pregnancy __% of total body water becomes ____
45-50, intravascular
In the case of Na+ retention in blood stream, we will see increased ___ follow
intravascular fluids
Arterial vs venous end of vessel filtration vs absorption state
At arterial end hydrostatic pressure is greater than plasma osmotic pressure (which is constant), resulting in net filtration, hydrostatic pressure progressively drops off eventually causing favor of absorption from plasma osmotic pressure on venous side
Osmolality definition
of milimose of solute particles per liter of solution, the greater the osmolallity the stronger urge water has to dilute the material
A healthy BUN is between ___ and ___. A healthy blood glucose is about ___. A healthy creatinine is between __ and ___.
10, 20. 100. .8-1.2
A very frequent cause of death in hospitalization is cerebral edema, this is when individuals vessels become ___tonic to the tissue surrounding them causing fluid buildup in the brain tissues
Hypo
Hypertonic by definition means ___solute compared to fluid, hypo means ____
more, less
Sensible water losses vs insensible water losses
Sensible losses are measurable and take the form of urine, include 1-2 L per day. Insensible loss is immeasurable and due to evaporative loss thru skin and respiratory tract and includes of to 600-900mL/day
3 factors that increase insensible losses
- add 10% for each degree of fever above 99 degrees
- increase with tracheostomies
- decrease with humidified ventilatory support
Daily sodium intake required, daily potassium intake required, why does hyperkalemia kill?
1 to 2 MEQ/kg/day
.5-1 MG/kg/day
Hyperkalemia causes arrhythmia and can stop a heart beat
Na+ HCO3-, and cl- are predominantly stored in ___cellular fluid, while K+, Mg2+, protein, and phosphates are stored in __cellullar fluid
Extra, intra
Na/K+ ATPase transports…
3 sodium ions outside the cell, and 2 potassium ions into the cell
1 liter of fluid = how many kg = how many lbs?
1kg, 2.2 lbs
1 gallon = how many liters?
3.78L
Hyponatremia is defined as serum Na+ …
135, 145
Most common cause of hyponatremia is from…
….H2O gain
Isotonic hyponatremia definition
Also knwon as factitous or pseudohyponatremia, this occurs when sodium levels are normal but measured low due to fats and proteins in the blood
Hypertonic hyponatremia definition
Increased solutes in plasma such as glucose or mannitol redistribute the volume of fluid from intra to extracellular space causing dilution resulting in hyponatremia
Hypotonic hyponatremia definition
Occurs when excess of H2O exceeds Na+ conc.
Euvolemic hyponatremia conundrum and how to evidence increased body H2O
-Occurs when patients have pure H2O excess extracellularly but not intravascularly, and appear euvolemic with the only evidence of increased total H2O is a lowered BUN
Hospitilization is required when Na+ drops below…
…125
Central pontine myelinolysis definition
Demyelination that occurs resulting in irreversible neurological defect after treatment of Na+ over 10 MEQ in 24 hrs or 18MEQ in 48 hrs
When treating a patient with hypernatremia need to give a __tonic solution first because…
isotonic, because it prevents cells from expanding too quickly and bursting by introducing fluid back in slowly until it can equally distribute and stabilize the BP
A drop of 1 MEQ/L of serum K+ indicates a….
200-400 MEQ deficit, very significant
Glucose and insulin administration can help drive ___ back into cells
K+
European black licorcie has the same effect in the body as…
…aldosterone
Bartter syndrome definition
Rare inherited defect in thick ascending limb of loop of henle characterized by low K+ levels and high pH
Hypokalemia is when K+ drops < ___MEQ/L, hyperkalemia is when K+ is > ___MEQ/L
3.5, 5.3
Correction for hypokalemia if <40k, what about if >40kg
.25 MEQ/kg/hr
10 MEQ/kg/2hrs
Symptoms of hyperkalemia (3)
- weakness
- flaccid paralysis
- hyperactive DTR’s
An EKG with a flat “T” wave and shortened QRS complex is a sign of… What about with peaked T waves and widened QRS complex
Hypokalemia, hyperkalemia
Calculation for fluid replacement therapy maintenance
- first 10 kg 100ml/kg/day
- 2nd 10 kg 50ml/kg/day
- remaining 20ml/kg/day
With a functioning kidney, an individual should intake approx ___L per day and urinate out that same amount
1.5-2L
Fluid replacement therapy’s formula is chosen to ensure good urine output in hospitalized patient, what is the minimal output to ensure good renal perfusion?
720mL/day
Sweating can cause a volume loss of __L/hr
1-2
Almost ___ L is lost each day to skin evaporation, respiration, and GI tract
1
IV fluid in mL/hr is summation of 5 items
- baseline maintenance
- deficit
- ongoing losses
- 3rd spacing
- compensatory
How much K+ must be added to each L of fluid? How much Na+?
20 mEQ, 50mEQ
Deficit formula
(.6 x weight)x(Na-140)/140
Calculation for fluid replacement therapy deficit
Acute loss give 1/2 deficit over first 8 hours, 1/4 deficit over next 8 hrs
Chronic loss give 1/2 deficit over 24 hours
