1. Chapter 17: Fluid, Electrolyte, and Acid-Base Balances

2. Distribution of Body Fluids
Intracellular fluid (ICF)
All fluids within body cells
42% of body weight
Extracellular fluid (ECF)
All fluid outside of cells
Divided into three smaller compartments
Interstitial
Intravascular
Transcellular

3. Composition of Body Fluids
Electrolytes
An element or compound which will separate into an electrically charged ion
Ions
Cations
Anions

4. Movement of Body Fluids
Diffusion
A solute in a solution moves fro an area of higher concentration to lower concentration
Osmosis
Movement of solvent across a semipermeable membrane from lower to higher concentration
Filtration
Water and diffusible substances move across a membrane in response to pressure
Active Transport
Movement of molecules or ions uphill against osmotic pressure

7. Regulation of Body Fluids
Fluid Intake
-Thirst mechanism
-Osmoreceptors
Hormonal
-ADH stored in posterior pituitary
-Angiotension I
-Angiotension II
-Aldosterone
Fluid Output
-Insensible loss
-Sensible loss
-Kidneys
-Skin
-Lungs
-GI track

8. Regulation of Electrolytes
Cations
Sodium
135 to 145 mEq/L
Potassium
3.5 to 5 mEq/L
Calcium
8.5 to 10.5 mg/dl
Magnesium
1.5 to 2.5 mEq/L
Anions
Chloride regulation
Bicarbonate regulation
Phosphorous-phosphate regulation

9. Regulation of Acid-Base Balance
Product of cellular metabolism and continually buffered
Buffer
Substance or group of substances that absorb or release hydrogen to correct acid-base balance pH
Reflection of the balance between carbon dioxide (an acid) and bicarbonate (a base)

10. Disturbances in Electrolyte and Fluid Imbalances
Sodium
Potassium
Calcium
Magnesium
Chloride
Fluid disturbances

11. Acid-Base Balance pH range 7.35 to 7.45 PaCO2 range is 35 to 45 mm Hg
PaO2 range is 80 to 100 mm Hg
Oxygen saturation should be over 90%
Base Excess range is +/– 2 mEq/L
Bicarbonate range is 22 to 26 mEq/L

12. Acid Base Imbalance Respiratory Acidosis  PaCO2,  pH
Respiratory Alkalosis
 PaCO2,  pH
Metabolic Acidosis
 Acid in the blood and loss of sodium bicarbonate
Metabolic Alkalosis
Loss of acid or  levels of bicarbonate

13. Assessment Nursing History - Age - Past medical history
- Recent surgery, trauma,
or respiratory disorder
- Environmental factors
- Diet history
Physical Assessment
- Check cardiovascular
- Oral cavity for signs of
dehydration
- Dizziness
- Lethargy
- Confusion
- Blurred vision

14. Measuring Fluid Intake, Output, and Daily Weight
Oral
NG tube
Jejunostomy feeding
IV fluids
Output
Urine
Diarrhea
Vomitus
Gastric suction
Blood
Drainage from wounds

15. Laboratory Studies Electrolytes Hematocrit Creatinine BUN
Urine specific gravity
ABG

16. Diagnosis Decreased cardiac output Acute confusion Diarrhea
Deficient fluid volume
Excess fluid volume
Risk for impaired fluid volume
Impaired gas exchange
Risk for injury
Ineffective peripheral tissue perfusion
Risk for decreased cardiac tissue perfusion
Risk for ineffective cerebral tissue perfusion
Risk for ineffective gastrointestinal perfusion
Risk for ineffective renal perfusion
Risk for shock

17. Planning Goals and outcomes Setting priorities Collaborative care
Set achievable goals in collaboration with patient and other health care members
Setting priorities
Base these on the nursing diagnosis selected
Collaborative care
Include patient, family members, discharge planner or social services as needed

18. Replacement of Fluid and Electrolytes
Oral
TPN
Crystalloids
Colloids

19. IV Therapy Vascular access Types of solutions
Maintenance of the system
Complications

21. Blood Replacement Autologous Allogenic or homologous Blood typing
Patient’s own blood is infused
Allogenic or homologous
Donor blood
Blood typing
ABO Rh
Transfusion reaction

23. Evaluation Focus on the goal of helping the patient
A successful outcome reveals the patients restorative of fluid and electrolyte balance.
Evaluate if you met the patient’s expectations

24. Practice Questions
1. A patient is diaphoretic and has an oral temperature of 104 degrees F. These are classic signs of which of the following?
A. ADH deficit
B. Extracellular fluid loss
C. Insensible water loss
D. Sensible water loss

25. Practice Questions (continued)
2. The body’s fluid and electrolyte balance is maintained partially by hormonal regulation. You will express an understanding of this mechanism in which of the following statements?
A. “The pituitary secretes aldosterone.”
B. “The kidneys secrete antidiuretic hormone.”
C. “The adrenal cortex secretes antidiuretic hormones.”
D. “The pituitary gland secretes antidiuretic hormone.”

26. Practice Questions (continued)
3. A senior student nurse delegates the task on intake and output (I&O) to a new nursing assistant. The student will verify that the nursing assistant understands the task of I&O when the nursing assistant states:
A. “I will record the amount of all voided urine.”
B. “I will not count liquid stools as output.”
C. “I will not record a café’ mocha as intake.”
D. “I will note perspiration and record it as small or large amount.”