Med Surg Exam 1 Flashcards
What is the role of the kidney’s in regulating the body’s fuid volume and and composition?
Regulates ECF volume and osmolality by excreting/retaining body fluids
Regulates electrolytes by selective retention of electrolytes or excretion of hydrogen ions
Regulates ECF by excretion or retention of hydrogen ions
Excretion of metabolic wastes or toxic substances
What is the role of the lungs in regulating the body’s fluid volume and composition?
They remove water (300mL daily)
What does the pituitary gland do to regulate the body’s fluid volume and composition?
Secrete AHD when dehydrated/during blood loss to increase reabsorption of water.
What does the adrenal cortex do to regulate the body’s fluid volume and composition?
Increases aldosterone to cause sodium and water retention, and potassium loss
Decreased aldosterone does the opposite
What do the parathyroid glands do to regulate the body’s fluid volume and composition?
Use parathyroid hormone to influence calcium and phosphate balance
What does the Renin-Angiotensin-Aldosterone system do to regulate the body’s fluid volume and composition?
Renin goes to the liver and converts a protein into angiotensin I, ACE converts that into angiotensin II, angiotensin II stimulates the the adrenal gland to produce aldosterone.
What does the hypothalamus do to regulate body fluid volume and composition?
During dehydration it secretes AHD to stimulate thirst, and for kidneys to increase water reabsorption.
What are the isotonic solutions we use?
0.9% NaCl (normal saline)
Lactated Ringer’s
5% Dextrose in Water
What is normal saline used for?
hypovolemia
shock
diabetic ketoacidosis
metabolic acidosis
hypercalcemia
What is LR used for?
hypovolemia
burns
fluid loss from diarrhea
acute blood loss
fluid loss from bile
What is D5W used for?
Hypernatremia
Fluid loss
dehydration
What are the hypotonic solutions?
0.45% NaCl (half strength saline)
What do we use half strength saline for?
hypertonic dehydration
Na+ or Cl- depletion
gastric fluid loss
What are the hypertonic solutions?
3% NaCl
5% NaCl
What are the hypertonic solutions used for?
Symptomatic hyponatremia
What lab values would you use to determine if someone is adequately hydrated?
BUN
Creatinine
Hematocrit
Urine Sodium
Urine Specific Gravity
Serum Osmolality
Urine Sodium
What does the BUN lab value show?
Measures the amount of urea in the bloodstream. Can vary with renal function, cellular breakdown, protein intake, and hydration status. Not an optimal gauge of kidney function.
What does the creatinine lab value show?
The breakdown product of muscle metabolism cleared from the bloodstream and excreted by the kidneys.
Accurate gauge of kidney function.
Does not vary with protein intake or hydration status
What does hematocrit measure?
The percentage of RBC in a volume of whole blood.
Decreased water increases the concentration of RBCs
Overhydrtion will decrease the RBC concentation
Anemia causes decreased hematocrit
What does the urine sodium lab value measure?
The level of sodium in the urine
As sodium intake increases, so does excretion
As fluid volume decreases, sodium is retained
What are risk factors for overhydration?
Age (disease)
- Too much intake
- Immobility
- Corticosteroids (puffy after taking)
- Burns (fluid shifts after burns-vascular damage)
- Heart and kidney failure
- Diet (sodium that comes mostly from packaged foods)
What are expected findings for overhydration?
Crackles lower lobes
- HTN most of time
- Polyuria (unless there is renal failure)
- Edema
- JVD, Ascites (fluid collects in the abdomen)
- SOB, Cough
- Weight gain (3 lbs in 24 hours, or 5 lbs in a week indicates fluid influence on weight)
What are lab tests for overhydration?
Decreased hematocrit and hemoglobin due to dilution
- Decreased osmolarity (amount of solutes in one volume of fluid)
- Urine sodium and specific gravity decreased
- CBC
What nursing care is performed for overhydration?
Daily weight
- Strict I&O (fluid restriction 2 L per day)
- Assess all s/s
- Restrict sodium to 2 grams per day
- Semi-Fowlers position
- Diuretics (furosemide - pulls fluid and potassium DEHYDRATION/HYPOKALEMIA CONCERN)