Fluids and electrolytes Flashcards
Water is __% of body weight in males
60
Water is __% of body weight in females
50
Water is __% of body weight in newborns
80
Intracellular water: / of TBW
Extracellular water: / of TBW
- Extravscular water / of extracellular water
- Intravascular water / of extracellular water
2/3
1/3
3/4
1/4
What compartments of fluid can colloids, saline and glucose enter?
Colloids - plasma
Saline - plasma and interstitial compartment
Glucose - Plasma, interstitial compartment, intracellular compartment
Physical examination of a dehydrated patient reveals (hypovolemia):
Skin turgor, dehydration of mucous membranes, thready peripheral pulses, increased resting HR, decreased BP
Decreased urinary flow rate
Hemodynamic measurements used in practice:
CVP
PA pressure
Daily water intake/loss is approximately _____mL
2500
Evaporative loss accounts for ____ heat loss
20-25%
Normal maintenence requiremtns for fluid:
4mL/kg/hr for first 10kg of body mass
2ml/kg/hr for second 10kg of body mass
1mL/kg/hr for any Kg>20kg
Difference b/w crystalloids and colloids
- Crystalloids - acqious solutuions of ions (salts) w/ or w/o glucose
- Colloids - contain high-molecular weight substances such as proteins or large glucose polymers
- Colloid - intravascular
- Crystalloid - entire extracellular fluid space
Hypernatremia is sodium above ___mmol/L
145
Hypernatremia causes:
Elevated sodium -> hyperosmolality -> cellular dehydration
Restlessness, lethargy, hyperreflexia -> seizures, coma, death
Hypovolemic hypernatremia causes:
Body fluid loss
Diuretic use
GI loss
Heat injury
Osmotic diuresis
Euvolemic hypernatremia:
Central diabetes insipidus
Nephrogenic diabetes insipidus
Fever
Hyperventialtion
Mechanical ventilation
Hypodipsia
Medications (amphoterecin, aminoglycosides, Li, phenytoin)
Sickle cell disease
Suprasellar and infrasellar tumors
Hypervolemic hypernatremia:
Cushing syndrome
Hemodialysis
Hyperaldosteronism
Iatrogenic (salt, water, saline, enema, IV HCO3, enteral feedings)
Hypernatremia treatment: oral ______ fluids
Examples:
Hypotonic
IV solution of 5% dextrose in water or hypotonic saline
Diuretics
Reduce level gradually 10meq/24h
Rapid correction of hypernatremia can cause?
Cerebral edema
Hypernatremic patients w/ decreased total sodium should be given ______ to restore plasma volume to normal prior to treatment w/ a hypotonic solution
isotonic fluid
Hypernatremic patients w/ increased total body sodium should be treated w/ a _____ and 5% IV dextrose in water
Treatment for diabetes insipidus?
loop diuretic
desmopressin
Dangers of saline and chloride rich crystalloids?
Hyperchloremic metabolic acidosis
Acute kidney injury
Hyponatremia is <______mmol/L
135
Most common cause of hyponatremia?
SIADH
Hyponatremia and hypernatremia can cause cerebral edema, how?
Hyponatremia due to movement of water from the blood into cells
Hypernatremia - only occurs in rapid correction
