Fluid & Electrolytes

Question 0

The acronym SALT can be used to remember the SxS of which electrolyte imbalance?

Answer 0

Hypernatremia

1) . S - Skin flushed
2) . A - Agitation
3) . L - Lowgrade fever
4) . T - Thirst

Question 1

How is the Anion Gap calculated? What is its significance and what is the normal range?

Answer 1

1) Anion Gap = (Cl + HCO3) - Na
2) Helps to differentiate among various acidotic conditions. The gap between the two measurements represents the anions not routinely measured (i.e., sulfates, phosphates, proteins, lactic acids and ketone acids). Because they aren’t measured in routine lab tests, the Anion Gap is a way of determining their presence.
3) 8 to 14 mEq

Question 2

How is Acidosis related Hyperkamlemia?

Answer 2

In Acidosis, H+ ions in the ECF increases and they start moving into ICF to maintain a balance. In order to keep the ICF electrical neutral, an equal number of K+ ions leave the cell, which causes Hyperkamlemia.

Question 3

How is Alkalosis related to Hypokalemia?

Answer 3

In Alkalosis, H+ ions are decreased in the ECF. Therefore, H+ ions move from the ICF to the ECF to balance out H+ ions. In order to keep the ICF electrically neutral, K+ ions move from the ECF to the ICF, which causes Hypokalemia.

Question 4

The acronym SUCTION can be used to remember the SxS of which electrolyte imbalance?

Answer 4

Hypokalemia.

1) S - Skeletal muscle weakness
2) U - U wave changes (elevated)
3) C - Constipation (Ileus)
4) T - Toxic effects from digoxin sensitivity
5) I - Irregular and weak pulse
6) O - Orthostatic hypotension
7) N - Numbess (paresthsias)

Question 5

What is the most prevalent ECG change in a patient with Hyperkalemia?

Answer 5

Tall and tented T-waves

Question 6

What is the normal range for the following electrolytes:

1) Sodium
2) Potassium
3) Chloride
4) Bicarbonate
5) Calcium (total)
6) Phosphate
7) Glucose
8) BUN
9) Creatinine
10) Albumin
11) Osmolality
12) Osmolarity

Answer 6

1) Sodium - 135 to 145 mEq/L
2) Potassium - 3.5 to 5.0 mEq/L
3) Chloride - 95 to 105 mEq/L
4) Bicarbonate - 22 to 26 mEq/L
5) Calcium (total) - 9 to 11 mg/dL
6) Phosphate - 2.5 to 4.5
7) Glucose - 70 to 110 fasting
8) BUN - 10 to 30 mg/dL (BUN:Cr = 10:1)
9) Creatinine - 0.5 to 1.5 mg/dL
10) Albumin - 3.5 to 5.0 g/dL
11) Osmolality (Serum) - 280 to 295 mOsm/Kg
12) Osmolality (Urine) - 50 to 1200 mOsm/Kg

Question 7

What is the normal range for Ionized Calcium?

Answer 7

4.5 to 5.1 mg/dL

Question 8

What is the difference between Total Serum Calcium level and Ionized Calcium level?

Answer 8

About 41% of all extracellular Calcium is bound to protein; 9% is bound to citrate or other organic compounds. The other 50% is ionized (meaning free or unbound). Ionized Ca is the only active form of Ca and therefore carries out most of the physiologic functions of the ion.

Question 9

In which 3 ways does PTH serve to increase the levels of Calcium in the serum?

Answer 9

1) PTH draws Ca from bones and transfers it to the serum
2) PTH promotes kidney reabsorption of Ca
3) PTH stimulates the small intestine to absorb Ca

Question 10

Why does serum protein abnormalities influence Total Serum Calcium levels and not Ionized Calcium level?

Answer 10

Total serum Calcium level includes the the 40% of Ca serum that is bound to protein (mainly albumin). Ionized Ca level includes free or unbound Ca and therefore isn’t affected by serum protein levels.

Question 11

In which 3 ways does Calcitonin serve to decrease the levels of Calcium in the serum?

Answer 11

1) Calcitonin inhibits bone resorption, which causes a decrease the amount of Ca available from bone.
2) Calcitonin decreases the absorption of Ca in the small intestine
3) Calcitonin enhances the excretion of Ca by the kidneys

Question 12

How does the level of Phosphorus affect Calcium levels?

Answer 12

Phosphorus inhibits calcium absorption in the small intestines (the opposite effect of vitamin-D). Also, when calcium levels are low and the kidneys retain calcium, phosphorus is excreted (they have an inverse relationship).

Question 13

How can renal failure cause Hypocalcemia, in regards to vitamin-D?

Answer 13

The kidneys activate vitamin-D, which is used to absorb calcium.

Question 14

How is Hypomagnesemia related to Hypocalcemia?

Answer 14

A low magnesium level can affect the function of the parathyroid gland and cause a ⬇ in Ca reabsorption in the kidneys and GI tract.

Question 15

What are 3 EARLY signs of Hypervolemia?

Answer 15

1) Weight gain
2) ⬆ BP
3) ⬆ Breathing effort

Question 16

How is 1000mL of D5W (Hypotonic inside the body) distributed among the body compartment when administered?

Answer 16

1) 2/3 or 667mL will go to the ICF

2) 1/3 or 333 mL will go to the ECF; of that 333 mL, 250 mL will go to the ISF while 80 mL will go to IVF.

Question 17

How is 1000mL of 0.9%NS (Isotonic inside the body) distributed among the body compartment when administered?

Answer 17

1000 mL (all of it) will stay in the ECF. However, 750 mL will go to the ISF and 250 mL will go to the IVF. Therefore, to give a person 1L of Intravascular fluid, you would have to fill them up with a total of 4 L of fluid.

Question 18

What are the 3 major intracellular ions and the 3 major extracellular ions?

Answer 18

1) Intracellular - Potassium, Magnesium, Phosphorus

2) Extracellular - Sodium, Chloride, Bicarbonate

Question 19

Which 8 things are included/tested in a BMP?

Answer 19

1) Sodium
2) Potassium
3) Chloride
4) Calcium
5) Bicarbonate
6) BUN
7) Creatinine
8) Glucose

Question 20

(T/F) Corticosteroids puts patients at risk for fluid overload.

Answer 20

True

Question 21

ADH can be stimulated by which 7 things?

Answer 21

1) ⬆ Osmolarity of blood
2) ⬇ Blood volume
3) Stress
4) Nicotine
5) Nausea
6) Morphine
7) SIADH

Question 22

What is the effect of SIADH and Diabetes Insipidus on serum Sodium?

Answer 22

1) SIADH - Only holds on to water (not Na). Therefore, Na is excreted and serum Na becomes hyyponatremic.
2) Diabetes Insipidus - Gets rid of water (not Na). Therefore, serum Na is hypernatremic.

Question 23

What is the effect of Hyperkalemia on Serum sodium levels?

Answer 23

Hyperkalemia causes secretion of Aldosterone, which in turn promotes retention of sodium and water and the excretion of potassium to restore balance.

Question 24

The excessive use of Fleet Enemas can cause which electrolyte imbalance?

Answer 24

Hypernatremia, because fleet enemas contain sodium

Question 25

Lactated Ringers solution contains which substances and electrolytes?

Answer 25

1) Sodium
2) Potassium
3) Calcium
4) Chloride
5) Lactate - Which is converted to bicarbonate by the liver.

Question 26

Lactated Ringers should not be used in patients with which 4 specific disorders and why?

Answer 26

1) Liver disease - Lactated Ringers contains Lactate which is usually converted into Bicarbonate by the liver, but cannot be done in patients with liver disease.
2) Patients with alkaline pH (> 7.5) - Because bicarbonate is formed as lactate breaks down, causing further alkalosis.
3) Patients with lactic acidosis - Because the ability to convert lactate into bicarbonate is usually impaired in these patients.
4) Patients with renal failure - Because it contains potassium and can cause Hyperkamlemia.

Question 27

How does ANP influence BP?

Answer 27

ANP influences BP by suppressing ADH and Aldosterone.

Question 28

What are the 4 Neuro symptoms of Hyponatremia and the 5 Neurosymptoms of Hypernatremia?

Answer 28

1) Hyponatremia - Headache, confusion, seizures, and coma.

2) Hypernatremia - Restlessness, agitation, twitching, weakness, and lethargy.

Question 29

What is the effect of insulin on serum potassium?

Answer 29

Insulin increases the uptake of potassium into cells, which could lead to Hypokalemia.

Question 30

Which specific drugs can cause Hypokalemia in the following manner:

1) Urinary wasting
2) GI Loss
3) Redistribution

Answer 30

1) Urinary wasting - Aminoglycosides, amphotericin B, corticosteroids, loop diuretics, levodopa, nifedipine, penicillin and rifampin.
2) GI Loss - Laxatives
3) Redistribution - Beta 2 agonists, lithium

Question 31

What is the difference between D5W and D5NS?

Answer 31

1) D5W is an isotonic solution that quickly turns hypotonic in the body when the sugar is metabolized.
2) D5NS is a hypertonic solution.

Question 32

What is the protocol for administering potassium to a patient who is Hypokalemic but still has a potassium level above 2.5 mEq/L?

Answer 32

1) Max infusion rate - 10 mEq/hr
2) Max concentration - 40 mEq/L
3) Max doses per 24 hrs - 200 mEq/24hrs

Question 33

What is the protocol for administering potassium to a patient who is Hypokalemic and has a potassium level below 2.0 mEq/L?

Answer 33

1) Max infusion rate - 40 mEq/hr
2) Max concentration - 80 mEq/L
3) Max doses per 24 hrs - 400 mEq/24hrs

Question 34

What are the symptoms of Hypokalemia?

Answer 34

1) Alkalosis
2) Shallow respirations
3) Irritability
4) Confusion and drowsiness
5) Weakness and fatigue
6) Arrythmias (irregular rate and tacchycardia)
7) Lethargy
8) Thready pulse
9) ⬇ Intestinal motility > N & V and Ileus

Question 35

Which three discussed classes of drugs are a main cause of Hyperkalemia?

Answer 35

1) Potassium-sparing diuretics (Spironlactone)
2) ACE inhibitors
3) NSAIDs (because they ⬇ the secretion of renin by the k kidneys)

Question 36

Which 4 methods can be used to treat Hyperkamlemia?

Answer 36

1) Calcium gluconate or Calcium Chloride - Antagonizes the action of Hyperkamlemia on the heart but does not ⬇ potassium levels.
2) Redistribution - Insulin can be used to ⬆ potassium uptake into the cell or Sodium Bicarbonate can be used to stop the transport of K+ ions out of the cell in an acidotic state.
3) Cationic Binding Resins - Meds such as Kayexalate bind K+ in the GI and you poop it out.
4) Renal elimination and dialysis

Question 37

Give 5 examples of Colloid (not Crystalloids) IV solutions.

Answer 37

1) Albumin in 5% solution
2) Dextran
3) Hetastarch
4) Hespan
5) Hextand

Question 38

What are the 4 common adverse effects of Colloid IV solutions?

Answer 38

1) Febrile reactions
2) Fluid overload
3) Allergic Rx’s
4) Coagulation abnormalities

Question 39

What are the 7 symptoms of Hyperkalemia?

Answer 39

1) Muscle twitches, muscle cramps and muscle weakness
2) Irritability and anxiety
3) ⬇ BP
4) Dysrhythmias (irregular rhythm)
5) ECG changes (mainly tall and tented T-waves)
6) Diarrhea and Abdominal cramps
7) Paresthesia