Fluids and Electrolytes Flashcards
Where is potassium reabsorbed in the nephrons?
The proximal tubule
Where is potassium reabsorbed in the nephrons?
The proximal tubule
How is potassium eliminated?
90% renally
10% in feces
What are 4 medications that can help bring potassium into cells?
Beta-adrenergic agents, insulin, aldosterone, and acid/base.
During acidosis would the patient be at risk for hyperkalemia or hypokalemia? Why?
Hyperkalemia because the body will push H+ into cells and exchange it with K+ to increase the pH of the blood.
During alkalosis would the patient be at risk for hyperkalemia or hypokalemia? Why?
Hypokalemia because there will be a lack of H+ and the body will push H+ out of the cell exchanging it with K+ and lead to a reduction in blood pH.
What is the serum potassium in hypokalemia?
If I give someone 10mEq of potassium how much will their serum levels of potassium increase?
0.1mEq/L.
How much potassium can be given orally at one time?
40mEq.
Can you push potassium IV?
No!
How much potassium can you give in a peripheral line?
10mEq/hour
How much potassium can you give in a central line?
20mEq/hour
What is the serum potassium level during hyperkalemia?
> 5mEq/L
What is the serum potassium level during hyperkalemia?
> 5mEq/L
How is potassium eliminated?
90% renally
10% in feces
What are 4 medications that can help bring potassium into cells?
Beta-adrenergic agents, insulin, aldosterone, and acid/base.
During acidosis would the patient be at risk for hyperkalemia or hypokalemia? Why?
Hyperkalemia because the body will push H+ into cells and exchange it with K+ to increase the pH of the blood.
During alkalosis would the patient be at risk for hyperkalemia or hypokalemia? Why?
Hypokalemia because there will be a lack of H+ and the body will push H+ out of the cell exchanging it with K+ and lead to a reduction in blood pH.
What is the serum potassium in hypokalemia?
For severe hyperkalemia, what are the acute temporary tx options?
10 units insulin + dextrose
Beta agonist
Bicarbonate
How much potassium can be given orally at one time?
40mEq.
Can you push potassium IV?
No!
How much potassium can you give in a peripheral line?
10mEq/hour
How much potassium can you give in a central line?
20mEq/hour
What is the most common form of potassium that we give?
KCl
What is the serum potassium level during hyperkalemia?
> 5mEq/L
What are 4 things that decrease the output of potassium?
Kidney disease
Medications
Acidosis
Diabetes
What are 4 things that increase input of potassium?
Over replacement
Overuse of K supplements
Medications
Potassium rich foods (kale)
Medications that reduce _______ secretion will cause a lower output of potassium.
Aldosterone
What are some symptoms of hyperkalemia?
Peak T waves on the EKG
Muscle cramping
Arrhythmias
When is hyperkalemia severe?
Potassium>7 or EKG changes
How do you treat severe hyperkalemia?
Stabilize the myocardium with Calcium IV. Then you use acute tx.
For severe hyperkalemia, what are the acute temporary tx options?
10 units insulin + dextrose
Beta agonist
Bicarbonate
Where is magnesium absorbed in the nephrons?
Loop of Henle
Where is magnesium found?
Bone and muscle
What is the serum level for hypomagnesemia?
What is the serum level for hypermagnesemia?
> 2.3mg/dL
What are the 4 big things that can lead to hypokalemia?
Diuretics, diarrhea, decreased absorption, and low magnesium
What are 4 causes of low magnesium?
Alcoholism, diarrhea, low calcium, and low magnesium.
What are symptoms of hypomagnesium?
Muscle cramping, disruption in nerve conduction (seizures, coma, etc.), sometimes asymptomatic, and QT prolongation (Torsades de Pointes)
How do you treat low magnesium?
You want to give magnesium through IV at a slow rate (usually MgSulfate). If you must use oral magnesium use MgOxide b/c of the high Mg percentage.
What are some causes of hypermagnesium?
Kidney failure or disease, over consumption of antacids, and over correction of hypomagnesium.
How do you treat hypermagnesium?
Avoid magnesium, diuretics, can use calcium chloride if they have an arrhythmia.
Where is phosphorus found?
Bone and intracellular fluid
Where is phosphorus reabsorbed in the nephrons?
The proximal tubule.
What is the serum level of hypophosphatemia?
What are some symptoms of hypophosphatemia?
Issues breathing, respiratory failure, body can’t use oxygen as efficiently, muscle cramping, rigid red blood cells, compromised immune system.
How do you treat hypophosphatemia?
You want to give PO over IV. You can give IV when the patient has diarrhea, which prevents absorption.
What are the serum levels for hyperphosphatemia?
> 4.5 mEq/L
What are some causes of hyperphosphatemia?
Renal failure, red blood cell lysis, a decrease in calcium, carbonated beverages.
What are some symptoms of hyperphosphatemia?
Usually asymptomatic
Muscle cramping
Calcium phosphate precipitation (can lead to obstructive nephrpathy)
How do you treat hyperphosphatemia?
Use binders to decrease the absorption of phosphorus (can be calcium acetate or aluminum, but you can’t use aluminum in patients with renal failure)
What are the serum levels in hypocalcemia?
What are some causes of hypocalcemia?
Hypomagnesemia, hypoparathyroidism, medications, not enough intake, not enough vitamin D.
What are the serum levels in hypercalcemia?
> 10.5 mg/dL
What are some causes of hypercalcemia?
Lithium, no excretion, too much bone resorption, lack of water
What are some symptoms of hypercalcemia?
Kidney stones, GI symptoms, short QT, and severe pain.
How do you treat hypercalcemia?
Rehydration, diuretics, sometimes calcitonin
What is the first line treatment for hypercalcemia in patients with cancer?
Bisphosphonates.
Might use corticosteroids may be used in cases of multiple myeloma or other malignancies where steroids are part of usual treatment
How do you treat hypercalcemia in patients with kidney disease?
Avoid diuretics
May need diuresis
What is normal osmolarity?
275-290 mOsm/kg
What do we give when a patient is severely hyponatremic?
100 mL 3% saline every 10 minutes
What is the rate at which you should correct hyponatremia if it is not severe?
8-10 mEq/L over 24 hours, or 18 mEq/L over 48 hours
When a patient has isotonic hyponatremia what must you rule out?
Pseudohyponatremia
What is the most common form of hyponatremia?
Hypotonic
How do you treat hypotonic hyponatremia?
Establish a volume status
