Ch 40.3 Fluids Flashcards
Sodium
- Because most abundant, exerts the greatest influence on the ECF osmotic concentration and water balance
- Increase in sodium intake causes increases blood volume
- Most abundant cation in ECF – 90% of sodium is in extracellular fluid
135–145 mmol/L
Potassium
Regulates many metabolic activities and is necessary for glycogen deposits in the liver and skeletal muscle, conduction of nerve impulses, normal cardiac conduction, and skeletal and smooth muscle contraction
3.5–5 mmol/L
Calcium
Necessary for bone and tooth formation, blood clotting, hormone secretion, cell membrane integrity, cardiac conduction, transmission of nerve impulses, and muscle contraction
1–1.2 mmol/L (serum ionized), 2.25–2.75 (total calcium)
Magnesium
Important for bone structure and neuromuscular function, including skeletal and cardiac muscle excitability
0.65–1.05 mmol/L
Chloride
Transport follows sodium
97–107 mmol/L
Bicarbonate
Essential component of the carbonic acid–bicarbonate buffering system, which is essential to acid–base balance
22–26 mmol/L (arterial), 24–30 mmol/L (venous)
Phosphate
Important role in the ICF, where it assists in the formation of high-energy compounds, such as ATP and nucleic acids, and in enzyme activity
0.9–1.45 mmol/L
Hypernatremia
lose more water than sodium; body fluids too concentrated, may be caused by diabetes insipidus, large insensible water loss without increasing intake, can have decreased LOC, seizures
serum sodium above 145mmol/L; serum osmolality over 300mmol/kg. Excess water loss or too much sodium intake. Body tried to reabsorb as much water as possible in kidneys.
Potassium is present in small amounts and so sensitive to fluctuations.
Hyponatremia
too much water, body fluids are too dilute. Water intoxication, too much water intake, water replacement after diarrhea or vomiting without sodium as well, excessive ADH, using a hypotonic irrigation solution., can present as decreased LOC and seizures
Sodium is too low; serum sodium below 135 mmol/L; serum osmolality under 280mmol/kg; most common electrolyte issue in elderly. The usual situation is a loss of sodium without a loss of fluid, which results in a decrease in the osmolality or concentration of ECF
Hypokalemia
low potassium below 3.5mmol/L; ECG abnormalities, bilateral muscle weakness, decreased bowel sounds with abdominal distension and constipation, dysrhythmias. Most common cause is is related to potassium wasting diuretic medications.
Hyperkalemia
high potassium over 5mmol/L; ECG abnormalities, bilateral muscles weakness, abdominal cramps with diarrhea; dysrhythmias, cardiac arrest. Usually caused by an underlyting disease… primarily renal failure… decreases the amount of potassium the kidneys are able to secrete.
Hypocalcemia
low serum calcium below 2.25mmol/L or serum ionized Ca2+levelbelow1.05 mmol/L; ECG abnormalities, numbness and tingling of fingers, toes and around mouth, hyperactive reflexes, muscle twitching and cramping, seizures, laryngospasms, dysrhythmias; positive Chvostek’s sign (contraction of facial muscles when facial nerve is tapped; usually caused by illness impacting the thyroid and parathyroid glands, prolonged bedrest or renal insufficiency.
Hypercalcemia
high serum calcium over 2.75mm/L or serum ionized Ca2+levelabove1.3 mmol/L; ECG abnormalities; anorexia, nausea, vomiting, constipation, diminished reflexes, decreased LOC, cardiac arrest. Usually symptom of underlying disease such as malignancy or hyperparathyroidism.
Hypomagnesemia
low serum magnesium below 0.65mmol/L; ECG abnormalities; can occur with malnutrition, malabsorption disorders, diarrhea and alcohol withdrawal, muscle twitching and cramping; hyperactive deep tendon reflexes; dysphagia, seizures, insomnia, hypertension, dysrhythmias
Hypermagnesemia
high serum magnesium over than 1.05mmol/L. ECG abnormalities; lethargy, hypoactive deep tendon reflexes; bradycardia, hypotension, decreased rate and depth of respirations; cardiac arrest
