Fluid & Electrolytes Flashcards
What are the two main compartments that fluid is divided into in the body?
Extracellular fluid (ECF)
Intracellular fluid (ICF)
- interstitial fluid (fluid b/w cells, blood, plasma
- transcellular fluid (CSF)
Where is most of the body’s fluid located?
Intracellular space (25 liters)
Water-pushing pressure
The force that pushes water outward from a confined space through a membrane
Example: BP
Hydrostatic Pressure
Clinical significance of changes in normal hydrostatic pressure
Edema
Water-pulling pressure created by proteins (notably albumin) in the circulatory
Pulls water into the circulatory system
Oncotic pressure/colloid osmotic pressure
Measurable fluid intake
PO fluids, IV fluids, Enteral feedings, irrigation fluids
Measurable fluid output
urine, sweating, emesis, feces
The kidneys release ____ in response to a decreased BP
Renin
Explain the renin-angiotensin II pathway
- Kidneys release renin
- Renin converts angiotensinogen (released by the liver) into angiotensin I
- Angiotensin I converted to Angiotensin II in the lungs
- Angiotensin II causes vasoconstriction and increases BP
How do ACE Inhibitors work?
Prevents the conversion of angiotensin I to II
Helps the body vasodilator and decrease BP
1 L of water = ____ kg
1 kg
therefore weight change of 1 lb = fluid volume change of about 500 mL
Assessment findings of fluid overload
Pulmonary crackles, lower extremity edema, JVD
Normal K+
3.5 - 5
What is the impact of hypokalemia on ECG?
ST depression, shallow/depressed T wave, prominent U wave
S/S of hypokalemia
dysrhythmias, constipation, palpitations, excessive fatigue, muscle damage/spasms numbness/tingling
IV K+ should not exceed ____ mEq/liter
is best at ____ mEq/liter
rate max is ____ mEq/hr
60
40
10-20
Important to remember about hypokalemia tx
check urine output - should be at least .5 mL/kg
oral K+ replacement are big pills that can be difficult to swallow - don’t crush/break these
IV: tough on veins, monitor for pain at IV site
What is the impact of hyperkalemia on ECG?
Widened QRS, ST elevation, narrow/peaked T wave
Can also lead to V fib and ventricular standstill
S/S of hyperkalemia
irritability, abdominal cramping, diarrhea, weakness, irregular pulses, cardiac arrest if sudden/severe
Tx for hyperkalemia
Kayexalate (binds to K+ in the colon in exchange for Na) - causes diarrhea
IV Calcium Gluconate
IV insulin/dextrose - moves K+ into the cells
Lasix - K+ wasting diuretic
Normal Na
135 - 145
Causes of hyponatremia
Loss of Na- excessive sweating, GI, diuresis
Dilutional- polydipsia, renal disease, increased ADH
S/S of hyponatremia
Impact is mainly on the nervous system
muscle cramps, weakness, fatigue
below 125 - progressive neuro symptoms, seizures, coma
Tx of hyponatremia
Fluid restriction - monitor Na levels q 6 hr and adjust accordingly
IV fluids w/ Na
Causes of hypernatremia
Loss of fluid - diarrhea, dehydration, diuretics, DI, fever
Gain of Na - Hypertonic IV fluids, saltwater near drowning, etc
S/S of hypernatremia
Nervous system symptoms
intense thirst, restlessness, agitation, altered mental status, seizures, coma
Tx of hypernatremia
Hypotonic IVF (low in Na), oral fluids
Normal Ca
8.8 - 10.5
Causes of hypocalcemia (book says below <9)
inadequate intake, inadequate Vit D, End stage kidney disease, diarrhea
acute pancreatitis, immobility, removal/destruction of parathyroid (secretes PTH which increases serum Ca)
S/S of hypocalcemia
think muscles and neuro
fatigue, depression, numbness, tingling, hyperreflexia, muscle cramps, tetany, seizures
Trousseau’s sign: BP cuff on arm causes flexion of the hand
Chvostek’s sign: eye twitch
Tx of hypocalcemia
Foods high in Ca, oral replacement, IV Ca gluconate
Causes of hypercalcemia
book says >11
kidney failure, hyperparathyroidism, immobility, use of steroids, dehydration
S/S of hypercalcemia
weakness, lethargy, confusion, coma, decreased reflexes, bone pain, fractures
Shortened QT interval, increased HR & BP
Higher risk for kidney stones
Tx of hypercalcemia
lasix, hydration (PO, fluids, Isotonic IV fluids), calcitonin (decreases calcium levels), weight bearing activities
Normal Cl
95 - 105
Normal Mg
1.8 - 3
Normal Phosphorus
3 - 4.5
Causes of hyperchloremia
metabolic acidosis, respiratory alkalosis, hypercortisolism
Causes of hypochloremia
fluid overload, excessive vomiting/diarrhea, adrenal insufficiency, diuretics
Causes of hypermagnesemia
kidney disease, hypothyroidism, adrenal insufficiency
Causes of hypomagnesemia
malnutrition, alcoholism, ketoacidosis
Causes of hyperphosphatemia
kidney disease, hypoparathyroidism, acidosis, hypocalcemia
Causes of hypophosphatemia
chronic antacid use, hyperparathyroidism, hypercalcemia, Vit D deficiency, alcoholism, malnutrition
