ELECTROLYTE DISORDERS Flashcards
What is caused by a serum sodium concentration less than 135mEq/L (135mmol/L)?
Hyponatremia
What is the most common electrolyte abnormality in hospitalized patients, often caused by hypotonic solutions, and usually reflects excess water – retention relative to sodium rather than sodium – deficiency?
Hyponatremia
True or False
Mismanagement of hyponatremia can result in neurologic catastrophes from cerebral osmotic demyelination
True
Evaluation for hyponatremia starts with a careful history for what?
- new meds
- changes in fluid intake
- changes fluid output
True or False
Symptoms of hyponatremia depend on the severity and acuity
True
Is mild hyponatremia (sodium concentration 130-135mEq/L) usually asymptomatic?
Yes
What are mild symptoms of hyponatremia?
- nausea
2. malaise
What are moderate symptoms of hyponatremia?
- headache
- lethargy
- disorientation
What are severe symptoms of hyponatremia?
- Respiratory arrest
- seizure
- coma
- brain damage
- brainstem herniation
- death
- Bad shit
What is the initial step in the management of hyponatremia?
restriction of free water and hypotonic fluid intake
free water intake should be less than 1-1.5 L/day
What may be necessary in patients with negative free water clearance?
hypertonic solutions
What is the most serious complication of hyponatremia caused from overly rapid sodium correction?
iatrogenic cerebral osmotic demyelination
What is a sodium concentration greater than 145mEq/L and is typically due to free water losses?
Hypernatremia
What are the primary defense mechanisms against hypernatremia?
- intact thirst mechanism
2. access to water
What are these signs and symptoms of?
- orthostatic hypotension
- oliguria
- Lethargy
- irritability
- weakness
Dehydration and early signs of hypernatremia
What are these signs and symptoms of?
- hyperthermia
- delirium
- seizures
- coma
Sever signs of hypernatremia
What is the treatment for hypernatremia?
- correcting cause of fluid loss
- replacing electrolytes
- replacing water
What is the treatment for hypernatremia?
- correcting cause of fluid loss
- replacing electrolytes
- replacing water
Hypernatremia
Fluids should be administered over a ____ hour period
48 hour
Aiming for serum sodium correction of 1 mEq/L/hr
Rapid correction of hypernatremia may cause what?
- cerebral edema
2. potentially severe neurologic impairment
What is a serum potassium level less then 3.5 mEq/L?
Hypokalemia
Severe hypokalemia may induce what?
- arrhythmias
2. rhabdomyolysis
True or False
Hypokalemia can result from insufficient dietary potassium intake and intracellular shifting of potassium from the extracellular space
True
What is the most common cause of hypokalemia?
GI loss from infectious diarrhea
Potassium concentration in intestinal secretion is ___ times higher than in gastric secretions
10 times
What are these symptoms of?
- muscle weakness
- fatigue
- muscle cramps
Mild to moderate hypokalemia
What are these symptoms of?
- flaccid paralysis
- hyporeflexia
- hypercrampia
- tetany
- rhabdomyolysis
Severe hypokalemia (less than 2.5 mEq/L)
What may an electrocardiogram show for a patient with hypokelmia?
- decreased amplitude and broadening T waves
- PVC
- depressed ST segments
What is the safest and easiest treatment for mild to moderate hypokalemia?
Oral potassium 40-100mEq/day over a period of days to weeks
What is a serum potassium level greater than 5.0mEq/L?
Hyperkalemia
Patients taking ACE inhibitors, ARB’s, or Potassium-Sparing diuretics may develop what?
Hyperkalemia
Hyperkalemia usually occurs in patients with what?
advanced kidney disease
Hyperkalemia
___ causes intracellular potassium to shift extracellularly
Acidosis
Hypernatremia impairs neuromuscular transmission, causing what?
- muscle weakness
- flaccid paralysis
- ileus
These are all changes in ECG’s associated with what?
- bradycardia
- PR interval prolongation
- peaked T waves
- QRS widening
- Conduction disturbances
a. bundle branch block
b. atrioventricular block - V-fib and cardiac arrest are terminal events
Hyperkalemia
Emergent treatment for hyperkalemia is indicated when?
- Cardiac toxicity
- muscle paralysis
- Severe hyperkalemia (greater than 6.5 mEq/L)
True or False
Insulin, bicarbonate, and beta-agonists all shift potassium intracellularly within minutes of administration for a patient with hyperkalemia
True
When giving insulin for treatment of hyperkalemia, should you give insulin to the patient as well?
YES
What may be given to a patient with hyperkalemia to antagonize the cell membrane effects of potassium?
IV calcium
What are some loop diuretics that can be used to treat hyperkalemia?
- Furosemide 40-80mg IV
2. Bumetanide 1mg IV
True or False
An IDC can manage severe hyperkalemia on their own.
FALSE
Severe hyperkalemia should be sent to the emergency department for immediate treatment (MEDEVAC DAT HOE)
