Fluid & Electrolytes Flashcards
What is necessary for life in relation to fluid and electrolyte balance?
The regulation of body fluid, fluid osmolality, and electrolytes
Fluid balance affects various physiological functions.
How does fluid in the body affect vital signs?
It influences workload of heart, formation of edema, and oxygenation
Vital signs can indicate fluid imbalance.
What is the primary component of body fluid?
Water
Fluid also contains electrolytes.
What happens if the quality of fluid or concentration of electrolytes strays outside precise boundaries?
Life-threatening disorders can occur.
What percentage of a typical adult’s body is fluid?
Approximately 60%
This percentage varies with age, body fat, and gender.
What are the two main compartments of body fluid?
Intracellular fluid (ICF) and extracellular fluid (ECF)
ICF makes up 2/3 and ECF makes up 1/3 of body fluid.
What is the function of extracellular fluid?
Carries oxygen and nutrients to, and waste away from cells.
What are the major cations in the body?
- Sodium
- Potassium
- Calcium
- Magnesium
- Hydrogen ions
What are the major anions in the body?
- Chloride
- Bicarbonate
- Phosphate
- Sulfate
- Negatively charged protein ions
What is hydrostatic pressure?
Pressure that a contained fluid exerts on what is confining it.
Define osmosis.
Movement of water through a semi-permeable membrane from low concentration to high concentration.
What is the normal serum osmolality range?
270-300 mosm/kg.
What is the primary regulator of fluid intake?
Thirst.
What is hypervolemia?
Expansion of the ECF due to an increase in total body sodium content and total body water.
What causes fluid volume excess?
- Overdose of fluids (oral, enteral, IV)
- Compromised regulatory systems (heart failure, kidney disease)
- Excessive sodium consumption
What are symptoms of fluid volume excess?
- Pulmonary edema
- Tachycardia
- Hypertension
- Weight gain
- Lethargy
- JVD
What is the goal of medical management for fluid volume excess?
Remove excess fluid from the body.
What is hypovolemia?
Lack of both water and electrolytes causing a decrease in circulating blood volume.
What are common causes of fluid volume deficit?
- Excessive gastrointestinal loss
- Excessive skin loss
- Excessive renal losses
- Hemorrhage or plasma loss
What laboratory findings are associated with fluid volume deficit?
- Increased serum and urine osmolality
- Elevated hemoglobin and hematocrit
- Increased BUN
What is the treatment for mild fluid volume deficit?
Oral rehydration.
What types of intravenous fluids are used for fluid replacement?
- Crystalloids
- Colloids
What characterizes isotonic fluids?
Osmolarity = 270-300 mosm/L; replenishes cells without changing shape.
What are the risks of using hypertonic fluids?
Can lead to dehydration.
What is the effect of hypotonic fluids on cells?
Causes osmotic movement of water into cells, expanding them.
What are gerontologic considerations for fluid imbalances?
- Subtle clinical manifestations
- Increased risk of delirium
- Dehydration is common
What is the sodium-potassium pump an example of?
Active transport.
