NUR 168: CHAPTER 40: FLUID,
ELECTROLYTE, ACID-BASE BALANCE
EXAM
Functions of Water in the Body:
•Transporting nutrients to cells and wastes from cells
•Transporting hormones, enzymes, blood platelets, and red and white blood cells
•Facilitating cellular metabolism and proper cellular chemical functioning
•Acting as a solvent for electrolytes and nonelectrolytes
•Helping maintain normal body temperature
•Facilitating digestion and promoting elimination
•Acting as a tissue lubricant
Two Compartments of Fluid in the Body:
•Intracellular fluid (ICF): fluid within cells (70%)
•Extracellular fluid (ECF): fluid outside cells (30%)
-Includes intravascular and interstitial fluids
-And Transcellular (pericardial, joint fluid, spinal fluid)
Variations in Fluid Content: Healthy Person:
•total body water is 50% to 60% of body weight
Variations in Fluid Content: Infant to Adult:
•An Infant has considerably more body fluid and ECF than an adult; more prone
to fluid volume deficits
Variations in Fluid Content: Gender & Fat Cells:
- women and obese people have less body water
Total Body Fluid Representing 50%-60% of Body Weight of Normal Adult:
- The desirable amount of fluid intake and loss in adults ranges from 1,500 to
3,500 mL each 24 hours, with most people averaging 2,500 to 2,600 mL per day.
- Although these figures are helpful guidelines, the person's health state as well
as balance between actual intake and loss must be considered when assessing
nursing needs.
,- A person's intake should normally be approximately balanced by output or fluid
loss.
- A general rule is that in healthy adults, the output of urine normally
approximates the ingestion of liquids, and the water from food and oxidation is
balanced by the water loss through the feces, the skin, and the respiratory
process.
- The intake-output balance may not always occur in a single 24-hour period but
should normally be achieved within 2 to 3 days.
Electrolytes:
- are substances that are capable of breaking into particles called ions
Electrolytes: Ions:
is an atom or molecule carrying an electrical charge
Ions: Cation:
- positive charge
Ions: Anions:
- negative charge
Homeostasis:
- total cations equal to total anions
Fluid Balance: Solvents:
•liquids that hold a substance in solution (water)
Fluid Balance: Solutes:
- Substances dissolved in a solution (electrolytes and nonelectrolytes)
Major Electrolytes: Sodium:
•controls and regulates volume of body fluids
Functions:
- Regulates extracellular fluid volume; Na+ loss or gain accompanied by a loss or
gain of water
- Affects serum osmolality
- Role in muscle contraction and transmission of nerve impulses
- Regulation of acid-base balance as sodium bicarbonate
Source & Losses:
- Normally enters the body through the gastrointestinal tract from dietary
sources, such as salt added to processed foods, sodium preservatives added to
processed foods
- Lost from gastrointestinal tract, kidneys, and skin
Regulation:
- Transported out of the cell by the sodium-potassium pump
- Regulated by renin-angiotensin-aldosterone system
, - Elimination and reabsorption regulated by the kidneys
- Sodium concentrations affected by salt and water intake
Major Electrolytes: Potassium:
•chief regulator of cellular enzyme activity and water content
Function:
- Controls intracellular osmolality
- Regulator of cellular enzyme activity
- Role in the transmission of electrical impulses in nerve, heart, skeletal,
intestinal, and lung tissue;Regulation of acid-base balance by cellular exchange
with H+
Source & Losses:
- Adequate quantities via a well-balanced diet
- Leading food sources: fruits and vegetables, dried peas and beans, whole
grains, milk, meats
- Lost via kidneys, stool, sweat, emesis
Regulation:
- Regulated by aldosterone
- Eliminated by the kidneys (no effective method of conserving potassium)
- Additional regulation via transcellular shift between the ICF and ECF
compartments
Major Electrolytes: Calcium:
•nerve impulse, blood clotting, muscle contraction, B12 absorption
Function:
- Role in blood coagulation and in transmission of nerve impulses
- Helps regulate muscle contraction and relaxation
- Major component of bones and teeth
Source & Losses:
- Absorbed from foods in the presence of normal gastric acidity and vitamin D
- Lost via feces and urine
- Sources include milk and milk products; dried beans; green, leafy vegetables;
small fish with bones; and dried peas and beans
Regulation:
- Primarily excreted by gastrointestinal tract; lesser extent by kidneys
- Regulated by parathyroid hormone and calcitonin
ELECTROLYTE, ACID-BASE BALANCE
EXAM
Functions of Water in the Body:
•Transporting nutrients to cells and wastes from cells
•Transporting hormones, enzymes, blood platelets, and red and white blood cells
•Facilitating cellular metabolism and proper cellular chemical functioning
•Acting as a solvent for electrolytes and nonelectrolytes
•Helping maintain normal body temperature
•Facilitating digestion and promoting elimination
•Acting as a tissue lubricant
Two Compartments of Fluid in the Body:
•Intracellular fluid (ICF): fluid within cells (70%)
•Extracellular fluid (ECF): fluid outside cells (30%)
-Includes intravascular and interstitial fluids
-And Transcellular (pericardial, joint fluid, spinal fluid)
Variations in Fluid Content: Healthy Person:
•total body water is 50% to 60% of body weight
Variations in Fluid Content: Infant to Adult:
•An Infant has considerably more body fluid and ECF than an adult; more prone
to fluid volume deficits
Variations in Fluid Content: Gender & Fat Cells:
- women and obese people have less body water
Total Body Fluid Representing 50%-60% of Body Weight of Normal Adult:
- The desirable amount of fluid intake and loss in adults ranges from 1,500 to
3,500 mL each 24 hours, with most people averaging 2,500 to 2,600 mL per day.
- Although these figures are helpful guidelines, the person's health state as well
as balance between actual intake and loss must be considered when assessing
nursing needs.
,- A person's intake should normally be approximately balanced by output or fluid
loss.
- A general rule is that in healthy adults, the output of urine normally
approximates the ingestion of liquids, and the water from food and oxidation is
balanced by the water loss through the feces, the skin, and the respiratory
process.
- The intake-output balance may not always occur in a single 24-hour period but
should normally be achieved within 2 to 3 days.
Electrolytes:
- are substances that are capable of breaking into particles called ions
Electrolytes: Ions:
is an atom or molecule carrying an electrical charge
Ions: Cation:
- positive charge
Ions: Anions:
- negative charge
Homeostasis:
- total cations equal to total anions
Fluid Balance: Solvents:
•liquids that hold a substance in solution (water)
Fluid Balance: Solutes:
- Substances dissolved in a solution (electrolytes and nonelectrolytes)
Major Electrolytes: Sodium:
•controls and regulates volume of body fluids
Functions:
- Regulates extracellular fluid volume; Na+ loss or gain accompanied by a loss or
gain of water
- Affects serum osmolality
- Role in muscle contraction and transmission of nerve impulses
- Regulation of acid-base balance as sodium bicarbonate
Source & Losses:
- Normally enters the body through the gastrointestinal tract from dietary
sources, such as salt added to processed foods, sodium preservatives added to
processed foods
- Lost from gastrointestinal tract, kidneys, and skin
Regulation:
- Transported out of the cell by the sodium-potassium pump
- Regulated by renin-angiotensin-aldosterone system
, - Elimination and reabsorption regulated by the kidneys
- Sodium concentrations affected by salt and water intake
Major Electrolytes: Potassium:
•chief regulator of cellular enzyme activity and water content
Function:
- Controls intracellular osmolality
- Regulator of cellular enzyme activity
- Role in the transmission of electrical impulses in nerve, heart, skeletal,
intestinal, and lung tissue;Regulation of acid-base balance by cellular exchange
with H+
Source & Losses:
- Adequate quantities via a well-balanced diet
- Leading food sources: fruits and vegetables, dried peas and beans, whole
grains, milk, meats
- Lost via kidneys, stool, sweat, emesis
Regulation:
- Regulated by aldosterone
- Eliminated by the kidneys (no effective method of conserving potassium)
- Additional regulation via transcellular shift between the ICF and ECF
compartments
Major Electrolytes: Calcium:
•nerve impulse, blood clotting, muscle contraction, B12 absorption
Function:
- Role in blood coagulation and in transmission of nerve impulses
- Helps regulate muscle contraction and relaxation
- Major component of bones and teeth
Source & Losses:
- Absorbed from foods in the presence of normal gastric acidity and vitamin D
- Lost via feces and urine
- Sources include milk and milk products; dried beans; green, leafy vegetables;
small fish with bones; and dried peas and beans
Regulation:
- Primarily excreted by gastrointestinal tract; lesser extent by kidneys
- Regulated by parathyroid hormone and calcitonin
