Pathophysiology Chapter 24
Hypernatremia may be caused by
decreased antidiuretic hormone secretion
Total body water in older adults is
decreased because of increased adipose tissue and decreased muscle mass
What age group has a larger volume of extracellular fluid than intracellular fluid?
infants
When a parent asks how they will know if their 2-month-old baby, who is throwing up and has frequent diarrhea, is dehydrated, the nurse's best response is
"If the soft spot on the top of his head feels sunken in and his mouth is dry between his cheek and his gums, then he is probably dehydrated."
Manifestations from sodium imbalances occur primarily as a result of
A gain of relatively more water than salt, prolonged of excess release of ADH, water intake that exceeds normal limit, a loss of relatively more salt than water
What is the most likely explanation for a diagnosis of hypernatremia in an elderly patient receiving tube feeding?
Inadequate water intake
For general good health, the nurse advises the older patient to do which of the following?
Advise elderly patients to stay hydrated, drink lots of fluids
Signs and symptoms of extracellular fluid volume include
Bounding pulse
How do clinical conditions that increase vascular permeability cause edema?
By allowing plasma proteins to leak into the interstitial fluid, which draws in excess fluid by increasing the interstitial fluid osmotic pressure
A patient, who is 8 months pregnant has developed eclampsia and is receiving intravenous magnesium sulfate to prevent seizures. To determine if her infusion rate is too high, you should regularly assess which of the following?
Check the patellar reflex; if it becomes weak or absent, her infusion rate probably is too high and she is at risk for respiratory depression or cardiac arrest
Clinical manifestations of hyponatremia include
Confusion, lethargy, coma, and perhaps seizures
Which alteration can lead to edema?
Decreased lymphatic flow
Signs and Symptoms of clinical dehydration include
Decreased urine output
Hyperaldosteronism causes
ECV excess and hypokalemia
When providing teaching to new parents about fluid and electrolytes in their newborn, what information does the nurse include?
Educate the parents about the newborn that they will loose 5% to 10% of body weight in the first few days as a normal adjustment
Which event is likely to lead to hyponatremia?
Frequent nasogastric tube irrigation with water
Decreases neuromuscular excitability is often the result of
Hypercalcemia and hypermagnesemia
Which electrolyte imbalances cause increased neuromuscular excitability?
Hypocalcemia and hypomagnesemia
A known cause of hypokalemia is
Pancreatitis
A patient diagnosed with chronic compensated heart failure reports that, "My feet swell is I eat salt but I don't understand why." The nurse's best response is:
Salt holds water in your blood and makes more pressure against your blood vessels, so fluid leaks out into your tissues and makes them swell
How is a patient hospitalized with a malignant tumor that secretes parathyroid hormone monitored for the resulting electrolyte imbalance?
Serum calcium, bowel function, level of consciousness
Which change in a patient's assessment has the greatest urgency?
Serum potassium concentration is increasing; has developed cardiac dysrhythmias, but denies any diffuculty breathing
The electrolyte that has a higher concentration in the extracellular fluid than in the intracellular fluid is _______ ions.
Sodium
The fraction of total body water (TBW) volume contained in the intracellular space in adult males is
Two-thirds
Osmoreceptors located in the hypothalamus control the release of
Vasopressin (antidiutretic hormone,ADH) (increased blood osmolarity)
The inward-pulling force of particles in the vascular fluid is called _______ pressure
capillary osmotic
Causes of hypomagnesemia include
chronic alcoholism
Effects of hypernatremia on the central nervous system typically include
confusion
Excessive antidiuretic hormone (ADH) secretion can cause _____ concentration.
decreased serum sodium
Clinical manifestations of severe symptomatic hypophosphatemia are caused by
deficiency of ATP
The nurse provides teaching regarding dietary intake of potassium to avoid an electrolyte imbalance when a patient
has chronic heart failure that is treated with diuretics
A person who has hyperparathyroidism is likely to develop
hypercalcemia
The imbalance that occurs with oliguric renal failure is
hyperkalemia
An increase in the resting membrane potential (hyperpolarized) is associated with
hypokalemia
A person who overuses magnesium-aluminum antacids for a long period of time is likely to develop
hypophosphatemia
Abnormalities in intracellular regulation of enzyme activity and cellular production of ATP are associated with
hypophosphatemia
A patient has a positive Chvostek sign. The nurse interprets this as a sign of
increased neuromuscular excitability
Clinical manifestations of moderate to severe hypokalemia include
muscle weakness and cardiac dysrhythmias
The process responsible for distribution of fluid between the interstitial and intracellular compartments is
osmosis
The person at highest risk for developing hypernatremia is a person who
receives tube feedings because he or she is comatose after a stroke.
Clinical manifestations of extracellular fluid volume deficit include
weak pulse, low blood pressure, and increased heart rate.