Exam 1: Potassium Imbalances Flashcards
What is Potassium?
A major intracellular electrolyte
Where is Potassium located?
98% of the bodys potassium is inside the cell
Where is the remaining Potassium located?
2% located in ECF, and important for neuromuscular function.
What does Potassium influence in ECF?
Skeletal and Cardiac Muscle Activity
Normal Serum Potassium concentration?
3.5 to 5 mEq/L
Potassium are commonly associated with?
Various diseases, injuries, medications, and acid-base imbalances
How much Potassium is excreted daily?
80% excreted through kidneys daily
Altername name for Potrassium Deficit?
Hypokalemia
Waht is Hypokalemia?
When serum Potassium Levels fall bellow 3.5 mEq/L, indicating a deficit in total potassium stores
Hypokalemia Contributing Factors
Diarrhea, Vomiting, Gastric Suction, Starvation, Diuretics
Hypokalemia Signs/Symptoms
Fatigue, Anorexia, Muscle Weakness, Decreased Bowel Motility, Decreased BP
Hypokalemia ECG (T)
Flattened T Waves
Hypokalemia ECG (U)
Prominent U Waves
Hypokalemia ECG (ST)
Depression
Hypokalemia ECG (PR)
Prolonged PR interveral
Hyperkalemia range?
> 5.0 mEq/L
Hyperkalemia Contributing Factors
Kidney Injury, Use of Potassium Conserving Diuretics, Addison Disease, Crush Injury, Burns, ACE Inhibitors
Hyperkalemia Signs/Symptoms
Muscle Weakness , Tachy/Bradycardia, Flaccid Paralysis, Cramps, Abdominal Distention, Anxiety
Hyperkalemia ECG (T)
Tall tented T waves
Hyperkalemia ECG (PR)
Prolonged PR intervals
Hyperkalemia ECG (QRS)
Prolonged QRS duration
Hyperkalemia ECG (P)
Absent P Waves
Hyperkalemia ECG (ST)
ST Depression
What diuretics can induce hypokalemia?
Thiazides and Loop Diuretics
Other medications that can lead to hypokalemia?
Corticosteroids, Sodium Penicillin ,and Amphotericin B
Another common cause of potassium depletion?
GI Loss. Votmiting and Gastric Sunction frequently lead to hypokalemia.
Potassium deficit occurs frequently with
diarrhea, may contain as much as 30 mEq/L
What does Hyperaldosteronism do and lead to?
Increases renal potassium wasting and can lead to sever potassium depletion
Primary Hyperaldosteronism is seen in patients with
adrenal adenomas
Secondary Hyperaldosteronism occurs in patients with
Cirrhosis, Nephrotic Syndrome, Heart Failure, or Malignant Hypertension
What does Magnesium depletion cause?
Causes renal potassium loss and must be corrected first; otherwise, urine loss of potassium will continue
If Prolonged, Hypokalemia can lead to
an inability of the kidneys to concentrate urine, causing idlute urine and excessive thirst
Potassium depletion spresses
the release of insulin and results in glucose intolerance
Urinary potassium excretion exceeding 20 mEq/day with hypokalemia suggests that
renal potassium loss is the cause
What is the corrected daily administration of potassium needed?
40 to 80 mEq/day
Diet for one with hypokalemia?
Diet containing sufficient potassium should be provided. Average is 50 to 100 mEq/day. Foods include fruits and vegetables, legums, whole grains, milk
IV route is mandatory for patients with severe hypokalemia, a range of
< 2 mEq/L
What signals warrant assessing teh serum potassiun concentration?
Fatigue, anoxeria, muscle weakness, decreased bowel motility, paraesthesias and dysrhythmias
Prevention for Hypokalemia
Encouraging patient to each foods rich in potassium.
How much Potassium is lost per liter of urine output?
40 mEq
Why should you be careful with Potassium and Urine Output?
Potassium is primarily excreted by the kidneys. Potassium administration can cause the serum potassium to rise dangerously.
Whats the Hyperkalemia range?
> 5 mEq/L
Hyperkalemia seldom occurs with
normal renal function
In older adults, there is an increased risk of hyperkalemia due to
decreases in renin and aldosterone as well as an increased number of comorbid cardiac conditions.
Hyperkalemia (Like Hypokalemia) is often caused by
iatrogenic (treatment-induced) causes.
Hyperkalemia is more dangerous because
cardiac arrest is more frequently associated with high serum potassium levels
Major causes of hyperkalemia are
decreased renal excretion of potassium, rapid administration of potassium, and movement of potassium from the ICF compartment to the ECF compartment
Hyperkalemia is comonly seen in patients with
untreated kidney injury
Patients with Hypoaldosteronism or Addison disease are at risk for hyperkalemia because
deficient adrenal hormones lead to sodium loss and potassium retention
Common Medications to cause Hyperkalemia?
KCl, Heparin, Ace Inhibitors, NSAIDS, Beta Blockers, Cyclosporine, Tacrolimus
In acidosis, potassium moves
out of the cells and into the ECF.
Elevated ECF Potassium level should be anticipated when
extensive tissue trauma has occured, as in burns, crushing injuries, or severe infections. Similarly, it can occur after chemotherapy
Most important consequence of hyperkalemia is its
effect on the myocardium.
At what level of potassium are cardiac effects present?
When the level is 8 mEq/L or greater. This may lead to ventricular dysrhythmias and cardiac arrest.
Hyperkalemia; what should be obtained immediately?
An ECG
What should be done ijf serum potassium levels are dangerously elevated?
May be necessary to administer IV calcium gluconate. It antagonizes the action of hyperkalemia on the heart
Loop Diuretics; Hyperkalemia
They increase excretion of water by inhibiting sodium, potassium, and chloride reabsorption in the ascending loop of Henle and distal renal tube
Hyperkalemia; Beta-2 Agonists
Highly effective in decreasing potassium, but cause tachycardia and chest discomfort
How do Beta-2 Agonists work
Move potassium into the cells and may be used in the absence of ischemic cardiac disease
Nursing Management for Hyperkalemia
Monitor for I/O, observe for signs of muscle weakness and dysrhythmias. Apical Pulse should be taken
What foods should be avoided in hyperkalemia
Vegetables, Fruits, Legumes, Whole-Grain breads, Lean Meat, Milk, Eggs
