Fluid, Electrolyte, and Acid-Base Imbalances Flashcards
Homeostasis
The state of equilibrium in the internal environment, naturally maintained by adaptive responses that promote health survival (stable internal environment)
Water content of body equation
1L or water = 2.2 pounds = 1kg
Body Fluid Compartments (Fluids)
Fluids
ICF and ECF
Interstitial and
blood
ECF volume deficit
Hypovolemia
-Abnormal loss of body fluids (diarrhea, vomiting, hemorrhage, or polyuria)
-Inadequate fluid intake
-Plasma to interstitial fluid shift (burns)
How does fluid volume deficit differ from dehydration
Loss of pure water without corresponding loss of sodium
ECF volume deficit interprofessional care
Correct the underlying cause and replace water and electrolytes
-orally
-blood products
-balanced (isotonic) IV solutions: 0.9 normal saline or lactated ringers
ECF volume deficit clinical manifestations
-Confusion, restlessness, drowsiness, lethargy
-Thirst, dry mucous membranes
-cold clammy skin
-decreased skin turgor
-decreased cap. refill
-postural hypotension (rx for falls!)
-increased HR
-low CVP
-low urine output, concentrated urine
-increased RR
-weakness and dizziness
-weight loss
-seizures and coma
ECF volume excess
Hypervolemia
-excess intake of fluids
-abnormal retention of fluids: HF or renal failure
-Interstitial to plasma fluid shift
ECF volume excess interprofessional care
Treat the underlying cause.
Remove fluid w/o changing electrolyte composition or osmolarity of ICF
-Diuretics, fluid restriction, restriction of Na
-Removal of fluids to treat ascites (paracentesis) or pleural effusion (thoracentesis)
-Monitor daily weights and I&O’s - Correlation is important.
ECF volume excess clinical manifestations
weight gain (most consistent sign)
-HA, confusion, lethargy
-peripheral edema
-JVD
-S3 heart sounds
-Bounding pulse
-Increased BP
-Increased CVP
-Polyuria
-Dyspnea, crackles, pulmonary edema
-muscle spasms
-seizure
-coma
Phosphorus Lab Value
3.0-4.5
Sodium Lab Value
136-145
Calcium Lab Value
9.0-10.5
Potassium Lab Value
3.5-5.0
Magnesium Lab Value
1.3-2.1
Hypernatremia
Na+>145
Causes of hypernatremia
-Inadequate water intake (unconscious, cognitively impaired)
-Excess water loss (diarrhea, high fever)
-Sodium gain (rare)
Causes hyperosmolality leading to cellular dehydration
MODEL
For hypernatremia (causes)
M-medications and meals
O- Osmotic diuretics
D- Diabetes Insipidus
E- Excessive water loss
L- Low water intake
Hypernatremia S/S
Depends
Decreased ECF
-Restlessness, agitation, lethargy, seizures, coma
-Intense thirst, dry swollen tongue, sticky mucous membranes
-Postural hypotension, decreased CVP, weight loss, increased pulse
-Weakness and muscle cramps
Normal/increased ECF volume
-restlessness, agitation, twitching, seizures, coma
-intense thirst and flushed skin
-weight gain, peripheral and pulmonary edema
-increased BP
-increased CVP
Hypernatremia treatment
Depends
Decreased ECF volume
-Fluid replacement, either PO or IV (isotonic IV: 0.9 normal saline)
Normal/increased ECF volume
-dilute the high sodium using sodium-free IV solutions (such as D5W)
-Promote sodium excretion with diuretics
-Dietary sodium restriction
-if altered sensorium or seizures, employ seizure precautions.
Hyponatremia
Na+<136
Results from loss of Na-containing fluids or from water excess (dilutional effect) or both
Usually associated with ECF hypoosmolality, fluids move into cells causing cellular edema
Hyponatremia causes
diuretics, vomiting, diarrhea, inadequate salt intake, hypertonic IV solutions, GI suctioning
Hyponatremia clinical manifestations
Mild- HA, irritability, difficulty concentrating
More severe- confusion, vomiting, seizures, coma
Hyponatremia management (nursing diagnosis)
Electrolyte imbalance, risk for injury, acute confusion.
Hyponatremia management
Loss of Na and fluids- administer isotonic IV solutions, encourage oral intake, stop diuretics.
Dilutional Hyponatremia- fluid restriction, diuretics, demeclocycline (increases renal response to ADH and produces diuresis)
correct sodium level slowly
Hyperkalemia
K+>5.0
Hyperkalemia caused by
massive intake of K+ (salt substitutes)
impaired renal excretion
shift from ICF to ECF (acidosis)
medications: digoxin, beta-blockers, ACE inhibitors, potassium sparing diuretics
Hyperkalemia manifestations
dysrhythmias
fatigue, confusion
tetany, muscle cramps
weak or paralyzed skeletal muscle
abdominal cramping, V/D
Hyperkalemia nursing diagnoses
electrolyte imbalance
activity intolerance
impaired cardiac output
potential complications: dysrhythmias
Hyperkalemia implementations
stop oral or parenteral K+ intake
increase K+ excretion (diuretics, kayexalate, dialysis)
Force movement of K+ from ECF to ICF using dextrose & insulin, sodium bicarbonate or (If no IV access) beta 2 agonist- albuterol
Stabilize cardiac membranes using IV calcium
Hypokalemia
K+<3.5
Hypokalemia caused by
GI losses (D/V)
Renal losses (magnesium deficiency, diuretics)
Metabolic alkalosis or insulin administration (shifts K+ into ICF)
Decreased dietary K+ intake
Hypokalemia S/S
Muscle weakness/ weakness of respiratory muscles/ skeletal muscle weakness (legs)
ECG changes
N/V
Decreased GI motility
Hyperglycemia
Hypokalemia nursing diagnoses
electrolyte imbalance, activity intolerance, impaired cardiac output, potential complications: dysrhythmias
Hypokalemia nursing implementations
Administration of potassium, increase dietary K+ intake
(oral is best, then IV)
