Electrolytes Flashcards
1
Q
Define an ion
A
An ion is any atom or group of atoms that bears one or more positive or negative electrical charges
2
Q
Define Cation
A
A positively charged ion
3
Q
Define anion
A
A negatively charged ion
4
Q
What are the 7 primary electrolytes?
A
Sodium
Potassium
Calcium
Magnesium
Chloride
Bicarb
Phosphorus
4
Q
Define an electrolyte
A
A substance that has a positive or negative electrical charge when it is dissolved in water
4
Q
T/F: electrolytes are passive solutes
A
False. Electrolytes are not passive solutes as they have charges and energy needs to be used in order to facilitate their movement
5
Q
What is a non-electrolyte?
A
A chemical compound that when placed in a solution does not ionize
6
Q
What is the normal value for sodium?
A
135-145 mEq/L
7
Q
What are common non-electrolytes?
A
Sugar
Alcohol
8
Q
What is the normal value for potassium?
A
3.5-4.5 mEq/L
9
Q
What is the normal value for chloride?
A
90-100 mEq/L
10
Q
What are the normal values for magnesium?
A
1.5-2.4 mEq/L
11
Q
What are the normal values for bicarb?
A
22-26 mEq/l
11
Q
What are the normal values for calcium?
A
4.5-5.5 mEq/dL
11
Q
What is the standard test for analyzing electrolyte content in the blood?
A
Basic metabolic panel
BMP
12
Q
What are the normal values for phosphorus?
A
3-4.5 mg/dL
13
Q
What metabolic functions can be tested via a Basic metabolic panel (BMP)?
A
Kidney function
Fluid and electrolyte balance
Blood sugar levels
Acid and base balance
Metabolism
14
Q
What is sodium primary role in the body
A
Primary role is regulating the distribution of water throughout the body
15
Q
What is the most prevalent cation found in the extracellular compartment?
A
Sodium
16
Q
What controls and regulates sodium levels?
A
The kidneys
17
Q
What level of sodium is required to be considered hyponatremic?
A
Less than 135 mEq/L
18
Q
What are common ways electrolytes are lost?
A
Vomiting
Diarrhea
19
Q
Besides increased output, what are other ways that sodium content in the blood can be decrease?
A
Increases in fluid levels in the body can dilute sodium content
20
Q
What disease processes commonly cause fluid retention?
A
CHF
Kidney failure
21
What level of sodium is required to be considered hypernatremic?
Greater than 145 mEq/l
21
What can cause hypernatremia?
Pure water loss or excretion
Diuretics
Excessive sweating
22
What is the main cation of the intracellular compartment?
Potassium
23
T/F: dehydration is not clinically confirmed with findings of hypernatremia
False
24
What can happen if potassium is too high or too low?
Serious cardiac dysrhythmias may develop
24
WHat are the most common causes of hypokalemia?
Urine
GI tract
Skin
NG tube output
Alcoholism, diuretics, laxatives
24
What is the role of potassium in the body?
Critical role is mediating electrical impulses in the nerves and muscles, including the heart
25
T/F: Potassium has no role in maintaining the acid base balance
False
26
What is the benchmark for being considered hypokalemic?
K+ less than 3.5 mEq/L
27
What are the symptoms of hypokalemia?
EKG changes
Muscle weakness
AMS (altered mental status)
28
How does hypokalemia change an EKG?
Decrease in the amplitude of the T waves
Decreased S-T segment
Prominent U waves
29
How is hypokalemia treated?
Eliminate beta agonists
KCl- for metabolic alkalosis
KHCO3- for renal tubular acidosis
30
What is the benchmark for hyperkalemia?
K+ > 4.5 mEq/L
31
What are the symptoms of hyperkalemia?
Muscle weakness
Changes in EKG
32
How does hyperkalemia change an EKG?
Tall narrow T waves (tent like)
Decreases amplitude of P wave (may disappear entirely)
Prolonged R-R interval
Prolonged QRS complex
May lead to asystole
32
What can cause hyperkalemia?
Pharmacologics
Lack of insulin
Renal insufficiency
33
What are treatment options for hyperkalemia?
insulin /glucose infusion
Calcium gluconate
Diuretics to promote K+ clearance
Kayexalate
Dialysis
Beta adrenergics
34
What drugs can cause hyperkalemia?
ACE inhibitors
Potassium sparing diuretics
NSAIDS
Heparin
35
What would the acid-base balance of a patient with hyperkalemia potentially look like?
Metabolic acidosis
36
What is the root cause of hyperkalemia?
Transcellular shift of K+ out of the cell
37
What is the most common clinical cause of hyperkalemia?
Impaired urine output
Or excessive intake
38
What does albuterol do to combat hyperkalemia?
May help shift potassium into the intracellular space by stimulating the sodium potassium pump
38
What drug can RTs administer to patients who are hyperkalemic?
Albuterol
39
How much can albuterol lower the serum potassium level of the blood?
0.5-1.5 mEq/L
40
What patients can benefit from albuterol administration for hyperkalemia?
Patients with renal failure who are fluid overloaded
41
What is the dosage of albuterol for patients with hyperkalemia?
20 mg
42
Where is the potassium concentration typically higher, outside the cell or inside the cell?
Inside the cell
Intracellularly
42
What is the resting membrane potential?
Difference of electrical voltage inside to the outside of the cell
43
What is the resting membrane potential dependent upon?
The functionality of the sodium potassium pump
44
Where is sodium concentration typically higher, outside the cell or inside the cell?
Outside the cell
Extracellularly
45
Describe the movement of sodium and potassium in a single “cycle” of the sodium potassium pump
The pump binds 3 sodium ions and 1 molecule of ATP
The ATP provides energy to change the shape of the channel and the sodium is excreted into the extracellular space
The new shape of the channel allows 2 potassium ions to bind
A release of phosphate allows the channel to revert to its original shape and release the potassium into the cell
46
What are the functions of magnesium in the body?
Plays important role as coenzyme in the metabolism of proteins and carbs
Helps regulate neuromuscular irritability
47
What is magnesium used to treat?
Torsade de pointes
Smooth muscle relaxation effects (asthma)
48
How is lactate used clinically?
Represents a clinically obtainable surrogate marker of tissue hypoxia and disease severity independent of blood pressure
48
What are normal serum lactate levels?
0.5-2.0 mmol/L
49
What causes an increase in serum lactate?
Anaerobic metabolism due to lack of oxygen delivery to the tissues
50
What ions are generally found in the extracellular compartment?
Sodium
Chloride
Bicarbonate
51
What ions are generally found in the intracellular compartment?
Potassium
Magnesium
Phosphate
52
Describe the relationship between hypervolemia and hyponatremia
In hypervolemia, the total body fluid has increased lowering the concentration of sodium in the blood
52
Describe the relationship between hypovolemia and hyponatremia
In hypovolemia the total body fluid has decreased resulting in decreased amounts of sodium
53
What causes hypernatremia?
Water loss exceeding sodium loss
Pure water loss
Increases in total body sodium
54
In what situations would water loss exceed sodium loss resulting in hypernatremia?
Diuretics
Sweating
Diarrhea
55
What conditions cause pure water loss resulting in hypernatremia?
Diabetes insipidus
Excessive sweating
56
hat can cause an increase in total body sodium resulting in hypernatremia?
Cushing syndrome
Hypertonic sodium bicarb administration
57
When is hypertonic sodium bicarbonate administered?
CPR
58
T/F: 90% of total body potassium is found extracellularly
False. 90% of total body potassium is found intracellularly
59
What can cause hypokalemia?
GI losses
Diuretics
insulin/ B2 agonists
Malnutrition
Alcoholism
60
What can cause hyperkalemia?
Acute or chronic renal failure
NSAIDS, diuretics, ACE inhibitors
Blood transfusion
61
What rhythm is associated with hypokalemia?
V-fib
Torsades de points
62
What is the role of calcium in the body?
Bone development
Blood clotting
Neuromuscular activity
Muscle contraction
63
What muscular symptoms might an individual with improper calcium levels experience?
Muscle irritability
Convulsions
Compromise of cardiac contractility
64
What is the anion gap?
The anion gap is the difference between the measured cations and the unmeasured anions in the blood
65
What is diagnosed if the anion is greater than normal?
High anion gap metabolic acidosis is diagnosed
66
What are the unmeasured anions?
Protein
Phosphate
Sulfate
Organic acids
67
What are the unmeasured cations
Potassium
Calcium
Magnesium
Trace
68
What is the normal anion gap?
Less than or equal to 15
69
How do you calculate the anion gap?
Unmeasured anions - unmeasured cations = anion gap
70
What are the options for fluid replacement?
Crystalloids
Colloids
Blood products
71
What is the first choice of fluid replacement for resuscitation, maintenance, solvent for drug administration?
Crystalloids
72
What are crystalloids primarily used for?
Resuscitation
maintenance
Solvent for drug administration
73
What fluid replacement is used as a plasma substitute?
Colloids
73
What are the benefits of crystalloids?
Do not exert an osmotic effect
Increase fluid levels without causing significant fluid shifts
74
what are common crystalloids?
normal/hyper/hypotonic saline
Dextrose
Lactated ringer
75
What are examples of colloids?
Albumin
Hesban
Hetastarch
76
What are the benefits of colloids?
Believed to remain in IV space and be more effective at maintaining oncotic pressure
77
What are blood products commonly used for?
Replacement therapy or hematocrit or hemoglobin
78
When are blood products typically used?
Rapid infusion protocol for trauma patients
79
What are the kinds of blood products?
Packed red blood cells
Fresh frozen plasma
Platelets
Cryoprecipitate
Whole blood
80
Why are blood transfusions considered risky?
Risk for adverse reactions
81
What are the 4 standard categories of diuretics?
Thiazides
Potassium sparing diuretics
Osmotic diuretics
Loop diuretics
