ELECTROLYTES PART 1 (CATIONS) Flashcards
1
Q
What are the Cations
A
- Na+
- K+
- Mg2+
- Ca2+
2
Q
- Most abundant cation (90 %) in ECF less concentration in ICF
A
Sodium (NA+)
3
Q
- Regulated by hormone aldosterone through reabsorption from the kidneys
A
Sodium (NA+)
4
Q
Functions of Sodium (NA+)
A
- Maintain Osmotic Pressure
- Prevent cell bursting
- Water balance and maintain Blood Pressure
- Neuromuscular excitability
5
Q
Sodium (NA+) regulated by
A
Anti-diuretic hormone
Aldosterone
Thirst
6
Q
increase secretion, increase Na reabsorption (hypernatremia)
A
Aldosterone
7
Q
water retention causes decrease of Na (dilutional hyponatremia)
A
Anti-diuretic hormone
8
Q
- Due to increase sodium loss or increase water retention
A
Hyponatremia (<135 mEq/L)
9
Q
Symptoms include
1. Nausea
2. Vomiting
3. muscle weakness
4. Lethargy
5. Headache
6. ataxia.
7. Severe neuropsychiatric symptoms (<125mEq/L)
A
Hyponatremia
Increased SODIUM LOSS
10
Q
Causes of Hyponatremia (SOIDUM INCREASE LOSS)
A
- Dehydration
- Vomiting
- Diarrhea
- severe burns
- metabolic acidosis
- renal disease
- Addison’s disease
- syndrome of inappropriate ADH secretion (SIADH)
- nephrotic syndrome
11
Q
- Marked hemolysis decreased sodium level due to dilutional effect.
A
Pseudohyponatremia
12
Q
may also falsely decrease serum sodium (due dilutional effect).
A
- Hyperlipidemia and hyperprotenemia
13
Q
- Increase sodium concentration due to loss of water, gain of sodium or both.
- Less common.
A
Hypernatremia (> 145 mEq/L)
14
Q
Symptoms include
1. Altered mental status
2. Lethargy
3. Irritability
4. Seizures
5. Muscle twitching
6. Hyper reflexes
7. Difficulty in breathing
8. Increase thirst
A
Hypernatremia
Increase sodium concentration
15
Q
Causes of Hypernatremia
(INCREASE SODIUM CONC.)
A
- Diabetes insipidus
- Renal disease
- Decrease water intake
- Fever
- Vomiting
- Alkalosis
- Severe burns
- Hyperadrenalism
- Diabetic coma
- Brain injury
16
Q
- Major cation in ICF and less in ECF.
- No renal threshold
A
Potassium (K+)
17
Q
Functions of Potassium (K+)
A
- Muscle contraction both skeletal and cardiac.
- Respiration.
- Muscle irritability
18
Q
Increase or decrease level of K may result to
A
muscle weakness
paralysis
cessation of cardiac contraction
19
Q
- Symptoms: weakness, fatigue, constipation, paralysis, difficulty in breathing.
- Causes: diarrhea, vomiting, renal disease, tumor, malabsorption, Cushing syndrome, hypomagnesemia, hyperaldosteronism, alkalosis.
A
Hypokalemia
20
Q
- The most common cause of hypokalemia due to
A
increase activity of aldosterone (hyperaldosteronism)
21
Q
causes direct K loss in the stool.
A
Diarrhea
22
Q
mainly result of K loss in the urine.
A
Vomitting
23
Q
Hypokalemia Effects in cardiac muscle
A
Decrease cell excitability
Cessation in heart contraction
24
Q
- decrease serum potassium
- Pseudohypokalemia
- Leukocytosis cause falsely decreases K. as seen in leukemia if sample left at room temperature.
A
Alkalosis:
25
causes falsely decreases K. as seen in leukemia if sample left at room temperature.
Leukocytosis
26
* The most common cause of hyperkalemia is _____ such as aldosterone deficiency and renal failure.
impaired renal excretion
27
* Symptoms: muscle weakness, tingling, numbness, mental confusion, cardiac arrhythmias.
* Causes: renal disease, Addison’s disease, diuretics, muscle injury, acidosis, hypo aldosteronism, haemolytic disease.
Hyperkalemia
28
Hyperkalemia Effects on cardiac muscle
lack of muscle excitability
cardiac arrest.
29
* Causes: Hemolysis, thrombocytosis, prolong tourniquet application, fist clenching, blood stored in ice, IV fluid.
Pseudohyperkalemia
30
potassium increases in?
Acidosis
31
Causes elevated serum potassium
Low Insulin
32
Captopril, digoxin, heparin therapy
Hyperkalemic drugs
33
* 2nd most abundant cation in the ICF.
* Supplied by diet.
Magnesium (Mg+)
34
3 forms of Mg in the blood
a. 55 %- free magnesium
b. 30 %- protein-bound
c. 15 % - complexed Mg
35
* 53%- found in the bone, 46 %- found in muscle and other organs.
Magnesium (Mg+)
36
% of free magnesium
55%
37
% protein-bound
30%
38
% complexed Mg
15%
39
FUNCTIONS of Mg
Muscle contraction
Heart Rhythm
Enzyme co factors
Maintain structure of DNA RNA and Ribosomes
40
Factors affecting magnesium in the blood
1. Parathyroid hormone (PTH)
2. Aldosterone and thyroxine
41
Increases renal reabsorption and intestinal absorption of magnesium.
Parathyroid hormone (PTH)
41
Increase renal excretion of magnesium.
Aldosterone and thyroxine
42
* Symptoms: arrhythmia, psychosis, weakness, cramps, depression, seizure, tetany, paralysis.
* Causes: malabsorption syndrome (sprue), malnutrition, chronic alcoholism, hyperaldosteronism, hyperthyroidism, acute renal failure, severe diarrhea.
Hypomagnesemia
42
* most commonly observed in ICU patients and undergoing diuretic therapy.
Hypomagnesemia
43
* Symptoms: hypotension, bradycardia, increase temperature, nausea, vomiting, lethargy.
* Causes: hypothyroidism, hyperaldosteronism, bone cancer, antacids, dehydration, Addison’s disease, acute renal failure
Hypermagnesemia
44
* Only 1 % found in the blood the rest in the bones.
Calcium (Ca2+)
45
Most abundant cation in the body
Calcium (Ca2+)
46
Calcium is absorbed in the
small intestine
47
Calcium in blood %
free calcium (ionized) the active form -
complex Ca -
protein bound -
50%
10%
40%
48
* Regulators of blood Calcium
Parathyroid hormone
Calcitonin
Vitamin D
49
Calcium Renal Threshold
> 10 mg/dl
50
FUNCTIONS of Calcium
1. Neurotransmitter regulator.
2. proper contraction of the heart.
3. For blood coagulation.
4. Enzyme activator.
5. Maintain bone and teeth structure.
51
Factors influencing serum calcium level
Parathyroid Hormone
Calcitonin
Active Vitamin D3
Plasma Protein
Serum/Plasma Phosphate
52
a. mobilizing calcium from the bones
b. increase synthesis of 1,25-dihydroxycholecalciferol
1. PTH (Parathyroid hormone)
53
produced by p-follicular cells of the thyroid gland
b. inhibits bone resorption by regulating the activity of osteoclasts antagonist to PTH
2. Calcitonin
54
undergoes hydroxylation producing 1,25 dihydroxycholecalciferols
3. Active Vitamin D3 (active calciferol)
55
direct relationship with calcium
4. Plasma protein
56
inverse relationship with calcium
5. Serum/Plasma Phosphate
57
Other factors affecting calcium level
Acidosis
Alkalosis
58
decreases protein binding resulting to increase calcium
Acidosis
59
increases protein binding resulting to decrease calcium.
Alkalosis
60
* Symptoms: muscle cramps, tetany, seizures, and arrhythmia.
* Causes: primary hypothyroidism, vit D deficiency, renal failure, Fanconi’s syndrome, hypoalbuminemia, pacreatitis, alkalosis
Hypocalcemia
61
* Symptoms: often asymptomatic, severe cases include mild weakness, lethargy, GI symptoms and renal discomfort.
* Causes: hyperthyroidism, acidosis, lung cancer, increase vit D, multiple myeloma, sarcoidosis.
Hypercalcemia
