Electrolytes Flashcards
Where is aldosterone found?
Adrenal glands
When is aldosterone released?
In response to low blood volume (think: vomiting, hemorrhage, etc)
What does aldosterone signal the body to retain?
Sodium and water
Na+ and H20
What happens to the blood volume when aldosterone is secreted?
It goes up.
What are the diseases caused by too much aldosterone?
Cushing’s and hyperaldosteronism (Conn’s)
What is the disease caused by too little aldosterone?
Addison’s Disease
What happens with too much aldosterone?
Fluid Volume Excess (FVE)
What happens with too little aldosterone?
Fluid Volume Deficit (FVD) think: dehydration
What is ADH?
Anti-Diuretic Hormone
Where is ADH found?
Pituitary
What problem do these key words potentially signal: craniotomy, head injury, sinus surgery, transsphenoidal hypophysectomy (removal of pituitary gland), any condition that can lead to increased ICP.
ADH problem
What is the pharmaceutical version of ADH?
Vasopressin (Pitressin)
What is SIADH (Syndrome of Inappropriate Anti-Diuretic Hormone)?
Too much ADH causing fluid volume excess. *think: too many letters, too much water!
What happens to the urine in SIADH?
It decreases.
Is the urine concentrated or dilute in SIADH?
Concentrated
What happens to the blood in SIADH?
Increased due to fluid volume excess.
Is the blood concentrated or dilute in SIADH?
Dilute due to fluid volume excess.
What is Diabetes Insipidus (DI)?
A syndrome of fluid volume deficit caused by lack of ADH. It has nothing to do with sugar!
What is a key symptom of Diabetes Insipidus?
Diuresis *think: “DI”uresis = “DI”
What is a major concern for patients with DI?
Shock because of rapid fluid loss.
Is the urine concentrated or dilute during DI?
Dilute
Is the blood concentrated or dilute during DI?
Concentrated due to fluid loss.
What do distended neck/peripheral veins indicate?
Fluid volume excess
Where is Central Venous Pressure (CVP) measured?
The right atrium.
What is a normal CVP range?
2-6 mm Hg
What is the cause of a high CVP?
Fluid volume excess. More volume equals more pressure!
Lung sounds are _____ during fluid volume excess?
Wet/crackles
What is the most commonly used loop diuretic?
Furosemide (Lasix)
What is the most commonly used potassium sparing diuretic?
Spironolactone
What should you think first with fluid retention?
Heart problems
What do the words “assessment” or “evaluation” in an NCLEX question indicate?
Look for presence or absence of pertinent signs and symptoms!
What is one non-pharmaceutical intervention that promotes diuresis?
Bed rest
How does bed rest induce diuresis?
By the release of Atrial Natriuretic Peptide (ANP) which reduces the production of ADH, thereby lowering Na+ and H20.
Both fluid volume excess and fluid volume deficit cause the heart rate to ____?
Go up.
Is blood pressure increased or decreased during fluid volume excess?
Increased. More volume, more pressure!
Is the blood pressure increased or decreased during fluid volume deficit?
Decreased. Less volume, less pressure!
What causes a fast, bounding pulse?
Fluid volume excess
What causes a weak, thready pulse?
Fluid volume deficit
What causes CVP to decrease?
Fluid volume deficit. Less volume, less pressure!
What happens to peripheral veins and neck veins during fluid volume deficit?
They vasoconstrict and become very tiny.
Urine specific gravity is ____ during fluid volume deficit?
Concentrated
What is a normal urine specific gravity range?
1.005 - 1.030
What does an isotonic solution do?
Goes “I”nto the vascular space and STAYS THERE!
What kind of solution is normal saline?
Isotonic. Goes and STAYS.
What kind of solution is Lactated Ringers?
Isotonic. Goes and STAYS.
What kind of solution is D5W?
Isotonic. Goes and STAYS.
When would you use an isotonic solution?
To replace fluids lost through cause, vomiting, burns, sweating, and trauma. *think: the fluid has left the vascular space and must be replaced with something that stays/replaces.
What is the basic solution used when administering blood?
Normal saline
When do you NOT use an isotonic solution?
In clients with hypertension, cardiac disease or renal disease.
What is a potential complication from administration of isotonic solutions?
Fluid volume excess, hypertension, hypernatremia.
What does a hypotonic solution do?
Goes into vascular space and then shifts OUT into to cells to replace cellular fluid. *think: hyp”O(UT)”tonic.
What is the benefit to using a hypotonic solution?
It rehydrates without causing hypertension, because the fluid does not remain in the vascular space and increase cardiac workload.
What kind of solution is D2.5W?
Hypotonic. Goes OUT of the vascular space.
What kind of solution is 1/2 NS?
Hypotonic. Goes OUT of the vascular space.
What kind of solution is 0.33% NS?
Hypotonic. Goes OUT of the vascular space.
When are hypotonic solutions used?
To rehydrate clients with hypertension, cardiac or renal disease. Also used to treat hypernatremia and cellular dehydration.
What is a potential complication of hypotonic solutions?
Cellular edema leading to fluid volume deficit and hypotension (“hypo”tonic could lead to “hypo”tension.
What is a hypertonic solution?
A solution packed with particles that expand volume and draw fluid into the vascular space from the cells. These are HIGH ALERT solutions. *think: hypE(nter)rtonic solutions ENTER the vascular space.
also, *think: HYPERtonic are HIGH alert, like a hyper person is constantly aware.
What kind of solution is D10W?
Hypertonic. ENTERS the vascular space.
What kind of solution is 3% NS?
Hypertonic. ENTERS the vascular space.
What kind of solution is 5% NS?
Hypertonic. ENTERS the vascular space.
What kind of solution is D5LR?
Hypertonic. ENTERS the vascular space.
What kind of solution is D5 1/2 NS?
Hypertonic. ENTERS the vascular space.
What kind of solution is D5NS?
Hypertonic. ENTERS the vascular space.
What kind of solution is TPN?
Hypertonic. ENTERS the vascular space.
What kind of solution is Albumin?
Hypertonic. ENTERS the vascular space.
What is the most common hypertonic solution?
TPN (also called PN)
When are hypertonic solutions given?
To clients with hyponatremia, or to those who have shifted large amounts of vascular volume to a 3rd space or has severe edema, burns or ascites.
What does a hypertonic solution do?
Returns volume to the vascular space.
What are potential complications of hypertonic solutions?
Fluid volume excess.
What solution is almost always only given in an ICU setting?
Hypertonic solutions, especially 3% NS and 5% NS.
Magnesium and calcium act like ____?
Sedatives.
What is a normal magnesium value?
1.3 - 2.1 mEq/L
What is a normal calcium value?
9.0-10.5 mg/dL *think: (CA)LL 9-11
What organ excretes magnesium?
The kidneys but can be lost in other ways (GI tract)
What should think on Mg and Ca questions?
Muscles!
What are causes of hypermagnesemia?
Renal failure, antacids
What electrolyte imbalance causes warmth and flushing?
Hypermagnesemia because Mg causes vasodilation.
Deep tendon reflexes are decreased or missing in what two electrolyte imbalances?
Hypermagnesemia and hypercalcemia.
What electrolyte imbalances cause weak/flaccid muscle tone?
Hypermagnesemia and hypercalcemia
What are symptoms that are shared by both hypermagnesemia and hypercalcemia?
arrhythmias, decreased pulse, decreased respiration, decreased LOC, decrease DTRs, weak muscle tone
What is the antidote for magnesium toxicity?
Calcium gluconate
How is calcium gluconate administered?
VERY SLOWLY IVP
How is hypermagnesemia treated?
Calcium gluconate, mechanical ventilation when respirations are less than 12, dialysis
What are causes of hypercalcemia?
Hyperparathyroidism, Thiazide, immobilization (you must bear weight to keep Ca in the bones)
What electrolyte imbalance causes brittle bones?
Hypercalcemia. Ca is pulled from the bones causing them to become brittle.
What electrolyte imbalance causes kidney stones?
Hypercalcemia. The majority of kidney stones are made of Ca.
What are the treatments for hypercalcemia?
Movement, fluids, steroids, phosphorus (bc of inverse relationship with Ca) added to diet (anything with protein), medications that decrease serum Ca like biphosphates and Calcitonin (osteoporosis med).
Too little Mg and Ca means?
Not enough sedative! Think “hyper” for all body systems.
What are causes of hypomagnesemia?
Diarrhea (lots of Mg is stored in the intestines), alcoholism
Which electrolyte imbalances cause rigid/tight muscles, a positive Chvostek sign and positive Trousseau’s sign?
Hypomagnesemia and hypocalcemia
Chvostek sign
Tap cheek and watch for twitching. “C” is for Cheek.
Trousseau’s sign
Pump up blood cuff and check for carpopedal spasm.
What are common symptoms of both hypomagnesemia and hypocalcemia?
Rigid muscles, postive Chvostek and Trousseau signs, stridor/laryngospasm (airway is smooth muscle!), arrhythmias, increased DTRs, mind changes, swallowing problems, seizure
What is the treatment for hypomagnesemia?
Give Mg (check kidney function before IV Mg), seizure precautions, eat foods rich in Mg like spinach, mustard greens, broccoli, pumpkin seeds, cucumber, green beans, other seeds, etc
What to do if client reports flushing and sweating during administration of IV magnesium?
Stop the infusion!
What are common causes of hypocalcemia?
Hypoparathyroidism, radical neck surgery, thyroidectomy. All of these equal = not enough PTH (parathyroid hormone) which decreases serum Ca.
What are the treatments for hypocalcemia?
PO calcium, IV Ca (give SLOWLY and make sure client is on heart monitor!), Vitamin D (bc it is converted in calcitrol which helps increase Ca absorption in the gut), phosphate BINDERS (bc of inverse relationship to Ca)
What are sevelamer hydrochloride (Renagel) and calcium acetate (PhosLo)?
Phosphate binders
What has an inverse relationship with calcium?
Phosphate. As it increases, Ca decreases and vice versa.
What electrolyte when given IV causes decreased heart rate and widened QRS complexes?
Calcium. Always administer IV Ca SLOWLY and ensure patient is on a heart monitor!
How does vitamin D increase calcium?
Vitamin D is converted into calcitrol by the liver and kidneys and helps intestines to absorb more Ca.
How does PTH (parathyroid hormone) decrease calcium levels?
PTH is released when blood Ca levels decrease and works to stimulate release of Ca from bones, reduce loss of Ca from kidneys thru urine, and indirectly increase Ca absorption in the gut. When there is too little PTH, serum Ca levels fall.
With what electrolyte imbalance should you think “neuro changes”?
Sodium
The serum sodium level is dependent on how much ____ we have in the body?
Water
Sodium level is inversely proportionate to ___ level?
Water. Too much water, too little sodium. Too little water, too much sodium.
Hypernatremia
Dehydration
Hyponatremia
Dilution
What are normal sodium levels?
135-145 mEq/L
What are causes of hypernatremia?
hyperventilation (insensible fluid loss), heat stroke, diabetes insipidus
Symptoms of hypernatremia?
Dry mouth, thirst, swollen tongue, neuro changes
What electrolyte should be checked daily for patients being tube fed?
Sodium. Feeding tube patients tend to become dehydrated.
Treatment for hypernatremia?
Restrict sodium, dilute with fluids
What are causes of hyponatremia?
Drinking plain water for fluid replacement after vomiting and sweating, psychogenic polydipsia, D5W (sugar and water solution), SIADH (retaining water)
What are the signs and symptoms of hyponatremia?
Headache, seizure, coma
What is the treatment for hyponatremia?
Replace sodium but NOT water! Give hypertonic (high alert!) solutions if having neuro problems.
What electrolyte is excreted by the kidneys?
Potassium
Normal K+ values?
3.5-5.5 mEq/L
What electrolyte imbalance causes bradycardia, tall peaked T waves, prolonged PR interval, flat or absent P waves, widened QRS, conduction blocks and v-fib?
Hyperkalemia
What electrolyte imbalance causes u waves, PVCs, and ventricular tachycardia?
Hypokalemia
What causes hyperkalemia?
Kidney failure/disease, use of spironolactone
What electrolyte imbalance begins with muscle twitching, proceeds to muscle weakness, and then flaccid paralysis?
Hyperkalemia
What has an inverse relationship with
sodium?
Potassium.
What are treatments for hyperkalemia?
Dialysis, calcium gluconate to decrease seizures and protect the myocardium, glucose and insulin to carry K+ into the cell, Kayexalate (enema that exchanges Na+ for K+ in the GI tract)
Why are insulin and glucose given to treat hyperkalemia?
Insulin carries glucose and K+ into the cell, thus lowering serum K+ levels.
Both hypo and hyperkalemia can cause what?
Life threatening arrhythmias
What are causes of hypokalemia?
vomiting, NG suction (lots of K+ in stomach), diuretics, anorexia/starvation
What are signs and symptoms of hypokalemia?
Muscle cramps/weakness, ECG changes (u waves, PVCs, v-tach)
Treatment for hypokalemia?
Give K+, spironolactone to retain K+, add K+ to diet
What is a major side effect of PO K+?
GI upset, give with food!
What to assess before giving IV potassium?
urinary output
Never give which electrolyte IVP?
Potassium
Always put which electrolyte on an IV pump?
Potassium
Which electrolyte burns during IV infusion?
Potassium
What electrolyte imbalance is seen with burn victims?
hyperkalemia due to the rupture/destruction of cells which release K+ into the blood
What kind of fluid is water?
Isotonic
What type of solution is used for irrigation?
Isotonic. Usually normal saline.
