ELECTROLYTES & BLOOD GASES Flashcards
(201 cards)
1
Q
Stimulates water reabsorption at the COLLECTING DUCT of the nephrons
A
ADH / AVP (Vasopressin)
*AVP = arginine vasopressin peptide
2
Q
Released from the myocardial atria in response to volume expansion, promotes SODIUM EXCRETION
A
Atrial natriuretic peptide
3
Q
A system that primarily responds to changes in plasma sodium and blood pressure
A
RAAS - renin angiotensin-aldosterone system
4
Q
RAAS
Low plasma sodium and blood pressure stimulates the kidneys (Juxtaglomerular apparatus) to release an enzyme called ___ ; converts angiotensinogen to angiotensin I
A
RENIN
5
Q
RAAS
A blood-borne substrate of RENIN ; produced by the liver and secreted to the blood
A
Angiotensinogen
6
Q
RAAS
An enzyme produced by the lungs ; acts on angiotensin I to be converted to angiotensin II
A
Angiotensin-converting enzyme (ACE)
7
Q
Inactive form of angiotensin
A
Angiotensin I
8
Q
Active form of angiotensin
A
Angiotensin II
9
Q
Immediate actions of angiotensin II
A
Promotes vasodilation of afferent arteriole
Vasoconstriction of efferent arteriole
Sodium reabsorption in PCT
Stimulates aldosterone secretion promoting sodium reabsorption in DCT
10
Q
Effect of increased sodium reabsorption in DCT (via the stimulation of aldosterone) to the plasma sodium
A
Increased
11
Q
Effect of increased potassium excretion (via aldosterone stimulation) to plasma potassium
A
Decreased
12
Q
Hormone that promotes sodium reabsorption in the DCT (increased plasma sodium) and promotes potassium excretion (decreased plasma potassium)
A
ALDOSTERONE
13
Q
Functions of electrolytes : volume and osmotic regulation
A
Na, Cl, K
Sodium, potassium, chloride
14
Q
Functions of electrolytes : myocardial rhythm and contractility and neuromuscular excitability
A
K, Mg, Ca
Potassium, Magnesium, Calcium
15
Q
Functions of electrolytes : cofactors in enzyme activation
A
Mg, Ca, Zn, Cl
Magnesium, Calcium, Zinc, Chloride
16
Q
Functions of electrolytes : regulation of ATPase-ion pumps
A
Magnesium
17
Q
Functions of electrolytes : blood coagulation
A
Ca, Mg
Calcium, magnesium
18
Q
Functions of electrolytes : production and use of ATP from glucose
A
Magnesium, phosphate
19
Q
Functions of electrolytes : maintenance of acid-base balance
A
HCO3, Cl, K
Bicarbonate, chloride, potassium
20
Q
Electrolyte photometric technique : measurement of light emitted by atoms following excitation by heat energy ; traditionally used to determine the concentration of Na, K and Li ; employs an internal standard
A
Flame photometry
21
Q
Internal standard for sodium and potassium
A
Lithium
22
Q
Internal standard for lithium
A
Cesium
23
Q
Electrolyte photometric technique : reference method for divalent cations (Mg and Ca) ; measurement of the amount of light absorbed by ground state atoms
A
Atomic Absorption spectrophotometry (AAS)
24
Q
light source for AAS
A
Hallow cathode lamp
25
Electrochemical technique : measurement of electric potential (voltage) due to the activity of free ions
Potentiometry
26
Electrochemical technique : H+ - sensitive glass electrode containing Ag/AgCl wire in electrolyte known pH and reference electrode (Hg/Hg2Cl2)
pH electrode
27
Electrochemical technique : pH electrode covered with membrane permeable to CO2 with bicarbonate buffer between membrane electrode ; also called as Severinghaus electrode
PCO2 electrode
28
Electrochemical technique : used to measure Na, K, Cl, I-Ca
Ion-selective electrode
29
Electrochemical technique : measurement of the amount of electricity in COULOMBS at a fixed potential
Coulometry
30
Coulometry : used in serum and and sweat chloride analysis ; endpoint is increased in conductivity measured by amperometry
Cotlove chloridometer
31
Electrochemical technique : measurement of the CURRENT FLOW produced by an oxidation-reduction at a fixed applied potential to the electrodes
Amperometry
32
Amperometry : uses a platinum cathode and Ag/AgCl anode covered with gas-permeable membrane which allows dissolved O2 to pass through
PO2 electrode
33
Electrochemical technique : measurement of current produced at GRADUALLY INCREASING voltage applied between two electrodes in contact with a solution containing the analyte
Polarography
34
Electrochemical technique : measurement of current flow as a metal is stripped off the anode of a polagraphic cell ; used for Pb and Fe testing (lead and iron)
Anodic stippling voltammetry
35
Electrochemical technique : measurement of osmolality indirectly by measuring one of the colligative properties of solution which change proportionally with the number of dissolved particles present
Osmometry
36
Colligative properties: As OSMOLALITY INCREASES for every 1 mole of solute, ___ and ____ also increase, while freezing point and vapor pressure are decreased
Boiling point and osmotic pressure
37
Colligative properties: As OSMOLALITY INCREASES for every 1 mole of solute, boiling point and osmotic pressure also increase, while ____ and ___ are decreased
Freezing point and vapor pressure
38
Most commonly used colligative property by clinical osmometers
Freezing point
39
Major extracellular cation ; major contributor to plasma osmolality ; principal osmotic particle outside the cell
Sodium
40
Sodium renal threshold
110-130 mmol/L (ave. 120 mmol/L)
41
Sodium reference value
136-145 mmol/L
42
Sodium panic values
120 mEq/L or less ; 160 mEq/L or greater
43
Most common method for sodium and potassium determination
ISE
44
ISE method : no sample dilution ; prevents pseudohyponatremia
Direct ISE
45
ISE method : with sample dilution ; prone to pseudohyponatremia
Indirect ISE
46
Color of sodium in flame photometry
YELLOW
47
Electrolyte method : an obsolete sodium colorimetric method
Albanese-Lein
48
Caused by loss of water, gain of sodium or both ; usually results from excessive water loss
Hypernatremia
49
Chronic hypernatremia in an alert patient is indicative _____
Hypothalamic disease
50
Major defense against hyperosmolality and hypernatremia
Thirst
51
Condition associated with the use of indirect ISE in the presence of increased plasma protein and lipid concentration
Pseudohyponatremia
52
Test performed when sodium is low due to pseudohyponatremia
Osmolality
53
Most common electrolyte disorder ; may lead to neuropsychiatric symptoms ; failure to concentrate the urine due to renal failure
Hyponatremia
54
Associated with hyperlipidemia and hyperproteinemia
Artifactual hyponatremia
55
Major intracellular cation ; 20x higher inside the cells ; otherwise known as “Kalium” ; permits neural signal to move down the nerve fiber ; most important analyte in terms of an abnormality being immediately LIFE THREATENING
Potassium
56
Potassium reference value (SERUM)
3.5-5.1 mmol/L
57
Potassium reference value (PLASMA)
3.5 - 4.5 mmol/L
58
Potassium panic value
2.8 mmol/L or less ; 6.2 mmol/L or greater
59
Antibiotic or electrode used for potassium measurement in ISE
Valinomycin-based electrode
60
Color produced by potassium in flame photometry
Violet
61
Lockhead-Purcell
Potassium measurement
62
Influx of potassium to the cells / cellular shift (potassium ions entering the cells in exchange of H+ release, resulting to low potassium level in the blood) ; GI loss and Renal loss (potassium excretion)
Hyponatremia
63
Efflux of potassium from the cells ; high potassium intake ; decreased renal excretion
Hyponatremia
64
Effect of hemoconcentration, hemolysis, and thrombocytosis to potassium (plasma sample)
Artifactual pseduohyperkalemia
65
Major extracellular anion ; passively follows sodium ; inverse relationship with bicarbonate
Chloride
66
Uses polocarpinne iontophoresis to stimulate sweat production with subsequent collection for analysis
Gibson and Cooke’s method
67
Chloride reference value (SERUM)
98-107 mmol/L
68
Chloride reference value (SWEAT)
<40 mmol/L
69
Chloride panic value (SERUM)
80 mmol/L or less ; 120 mmol/L or greater
70
Chloride panic value (SWEAT)
60 mmol/L or greater (cystic fibrosis)
71
ISE method for chloride is made of
Tri-n-octylpropylammonium chloride decanol (TNOPAC)
72
Chloride method : Coulometric-amperometry titration
Cotlove chloridometry
73
Chloride method : Mercuric titration using mercuric nitrate and diphenylcarbazone indicator (BLUE-VIOLET)
Schales-Schales
74
Chloride method : spectrophotometric assay using mercuric thiocyanate (Red complex)
Whitehorn titration
75
Aldosterone deficiency, salt-losing nephropathy, DKA, prolonged vomiting or diarrhea, compensated respiratory acidosis
Hypochloremia
76
Renal tubular acidosis, GI loss of bicarbonate, metabolic acidosis, compensated respiratory alkalosis
Hyperchloremia
77
Second major extracellular anion ; comprises >90% of the total CO2 at physiologic pH
Bicarbonate
78
Total CO2 Reference values
23-27 mmol/L
79
Bicarbonate Reference values
22-26 mmol/L
80
Directly measured as part of ABG
Total CO2
81
ABG parameter that is calculated
Bicarbonate
82
Bicarbonate panic value
10 mmol/L or less ; 40 mmol/L or greater
83
Methods (Total CO2) : involves acidification of the sample followed by electrode-based detection of released CO2
ISE
84
Bicarbonate clinical significance : metabolic acidosis, compensated respiratory alkalaosis, renal tubular acidosis, GI loss of bicarbonate
Low bicarbonate
85
Bicarbonate clinical significance : metabolic alkalosis compensated respiratory acidosis
High bicarbonate
86
Panic value for bicarbonate
10 mmol/L and below ; 40 mmol/L and above
87
2nd major intracellular cation ; Cofactor of > 300 enzymes ; 13x higher inside RBCs
Magnesium
88
Magnesium distribution : 55%
Ionized
89
Magnesium distribution : 30%
Bound to proteins
90
Magnesium distribution : 15%
Bound to ions
91
Reference method for magnesium determination
AAS
92
Magnesium panic values
1 mg/dL and below ; 4.7 and above mg/dL
93
Plasma level is regulated by PTH, active vitamin D, calcitonin
Calcium
94
Stimulates bone resorption, vitamin D activation, and calcium reabsorption leading to a net increase in plasma calcium level
Parathyroid hormone
95
25(OH)D3
Inactive form of vitamin D a
96
1,25(OH)2D3
Active form of vitamin D
97
Active vitamin D other name
Calcitriol
98
Stimulates intestinal absorption of calcium (increased plasma calcium level)
Active vitamin d
99
Inhibits PTH action ; hypocalcemic
Calcitonin
100
Promotes PO4 excretion
PTH
101
Promotes PO4 reabsorption
Active vitamin D
102
Calcium distribution : 50%
Ionized
103
Calcium distribution : 40%
Bound to proteins
104
Calcium distribution : 10%
Bound to ions
105
Calcium panic value
6 mmol/L and below ; 13 mmol/L and above
106
Reference method for calcium determination
AAS
107
ISE consists of PVC membrane impregnated with a calcium ion exchanger ; used to measure ____
Ionized calcium
108
Dye-binding (CALCIUM) : requires addition of 8-HYDROXYQUINOLINE to prevent magnesium interference
O-cresolphthalein complexone (CPC) method
109
Major intracellular anion ; component of several essential biomolecules
Phosphate
110
Phosphate is usually measured as
Inorganic phosphate
111
Phosphate panic value
1 mg/dL and below ; 8 mg/dL and above
112
By-product of anaerobic glycolysis
Lactate
113
Accumulation of lactate in the blood indicates ____
Hypoxia
114
Lactate is converted back to glucose by the _____ through the process called _____
Liver ; gluconeogenesis
115
Physical property of a solution that is based on the concentration of solutes (Expressed as milliosmoles) per kilogram of solvent ; affected only by the number of dissolved particles present
Osmolality
116
Specimen for osmolality
Serum
117
Based on the measurement of a decrease in ____
Freezing point
118
Calculated osmolality
2Na + (glucose/18) + (BUN/2.8)
119
Osmolal gap formula
Measured Osm - Calculated Osm
120
Effective screening method in detecting the presence of toxic compounds
Osmolal gap
121
Reference values : serum osmolality
275-295 mOsm/kg
122
Reference values : osmolal gap
5-10 mOsm/kg
123
Clinical significance (OG >12 mOsm/kg)
Lactic acidosis
Uremia
Diabetic ketoacidosis
Intoxication : alcohols, ethylene glycol and salicylate
“LUDI”
124
Used as a form of quality for electrolyte analyzers
Anion gap
125
Anion gap formula : with potassium
Reference value : ?
(Na + K) - (Cl + HCO3)
10-20 mmol/L
126
Anion gap : potassium is omitted
Reference value: ?
Na - (Cl + HCO3)
7-16 mmol/L
127
Increased Anion gap : INCREASED unmeasured anions
Methanol, uremia, DKA, Paraldehyde, inhalants, lactic acidosis, ethylene glycol, salicylate
“MUDPILES”
128
Increased Anion gap : DECREASED unmeasured cations
Hypocalcemia
129
Increased Anion gap : lab error
Falsely increased sodium
Falsely decreased chloride/bicarbonate
130
Decreased anion gap : DECREASED unmeasured anions
Hypoalbuminuria
131
Decreased anion gap : INCREASED unmeasured cations
Hypercalcemia, multiple myeloma
132
Decreased anion gap : lab error
Falsely decreased sodium
Falsely increased chloride/bicarbonate
133
Substance that can yield hydrogen ions (H+) when dissolved in water (Arrhenius) ; proton donor (Bronsted and Lowry)
Acid
134
Substance that can yield hydroxyl ions (OH-) ; proton acceptor
Base
135
Combination of a weak acid and its salt or conjugate base that resists changes in pH
Buffer
136
Buffer system : second most important blood buffer ; contains 38 histidine residues that bind H+
HEMOGLOBIN
137
Have free carboxyl and amino groups that are able to bind H+
PLASMA PROTEINS
138
Uses HPO42- (hydrogen phosphate) and H2PO4- (dihydrogen phosphate) to minimize pH changes in plasma and erythrocytes
Phosphate buffer
139
Uses HPO42- (hydrogen phosphate) and H2PO4- (dihydrogen phosphate) to minimize pH changes in plasma and erythrocytes
Phosphate buffer
140
Most important buffer system in the blood
Bicarbonate / carbonic acid buffer system
141
Henderson-Hasselbach equation : the numerator (bicarbonate) denotes function of the __ and __ to pH
Kidney ; directly proportional
142
Henderson-Hasselbach equation : the denominator (pCO2 or H2CO3 - carbonic acid) denotes function of the __ and __ to pH
Lungs ; inversely proportional
143
When the ratio between HCO3 and H2CO3 is 20:1, the pH is
7.4
144
Preferred anticoagulant for blood gas analysis
Lyophilized heparin
145
ABG must be assayed within __ mins
15mins
146
Method used for the measurement of pH and pCO2
Potentiometry
147
pH calibration
2 phosphate buffers stored anaerobically at room temperature
148
Method used for pO2 measurement
Amperometry
149
PH
Reference range
Panic value
7.35-7.45
7.2 and below ; 7.6 and above
150
pCO2
Reference range
Panic value
35-45 mmhg
20 mmhg and below ; 60 mmhg and above
151
pO2
Reference range
Panic value
80-100 mmhg
40 mmhg and below
152
HCO3
Reference range
Panic value
22-26 mmol/L
10 mmol/L and below ; 40 mmol/L and above
153
Total CO2
Reference range
23-27 mmol/L
154
Base excess
Reference range
-2 to +2
155
O2 saturation
Reference range
>95%
156
causes of shit to the right in oxyhemoglobin dissociation curve
High lahat
C = pCO2
A = Acid pH (high H+)
D = 2,3-DPG
E = Excessive exercise
T = temperature
157
Electrode chambers of blood gas analyzers are thermostatically controlled at ______
37 +/- 0.1 C
158
For every 1C increase in body temperature, pCO2 increases by ____ ; pO2 decreases by ____ and pH decreases by ____ unit
3% pCO2 ; 7% pO2 ; pH 0.015 unit
159
Specimen exposure to air
Low pCO2, high pO2, and high pH
160
Prolonged storage of specimen (anaerobic)
High pCO2, low pO2, low pH
161
Excess anticoagulant : dry heparin
Low pH
162
Excess anticoagulant : liquid heparin
Low pCO2
163
Major causes of metabolic acidosis
Ketoacidosis
Hypoxic acidosis
Renal failure
Renal tubular acidosis
Loss of bicarbonate
164
Major causes of metabolic alkalosis
NaHCO3 overdose
Hypokalemia
Vomiting
GI suction
Corticosteroid excess
165
Major causes of respiratory acidosis
COPDs
Acute airway obstruction
Circulatory failure
Impaired respiratory system
166
Major causes of respiratory alkalosis
Hypoxia-induced hyperventilation
Anxiety
Pulmonary embolism
Pulmonary edema
167
Metabolic acidosis compensation
Hyperventilation
168
Metabolic alkalosis compensation
Hypoventilation
169
Respiratory acidosis compensation
HCO3 reabsorption
170
Respiratory alkalosis compensation
HCO3 excretion
171
Component of heme -containing substances
Iron
172
Iron transport protein
Transferrin
173
Iron storage forms
Ferritin and hemosiderin
174
Serum Iron reference range
50-160 mgdL
175
Methods involve addition of sufficient ferric ions to saturate transferrin followed by removal of excess iron and measurement of bound iron by the same procedure used for serum iron
TIBC
176
TIBC estimation formula
TIBC (ug/dL) = transferrin (mg/dL) x 1.43
177
% saturation / transferrin saturation formula
(Serum Fe / TIBC) X 100
178
% saturation reference range
20-50%
179
Best test for iron deficiency ; determined using immunoassay
Ferritin
180
IDA
Serum iron
% saturation
TIBC (tf)
Ferritin
⬇️
⬇️
⬆️
⬇️
181
Anemia of chronic inflammation
Serum iron
% saturation
TIBC (tf)
Ferritin
⬇️
⬇️
⬇️
⬆️
182
Hemochromatosis
Serum iron
% saturation
TIBC (tf)
Ferritin
⬆️
⬆️
⬇️
⬆️
183
Cofactor for approximately 300 enzymes ; associated with acrodermatitis eneterohepatica, chronic liver and kidney disease, alcoholism
Zinc
184
Component of several metalloenzymes ;
Copper
185
Failure of copper absorption
Menke’s syndrome / kinky hair syndrome
186
Failure to excrete copper in bile, excess copper in liver, brain, and eyes (cornea) / kayser fleischer ring
Wilson’s disease
187
Fat soluble vitamins
ADEK
188
Retinol ; night blindness
Vit A
189
Cholecalciferol ; rickets, osteomalacia
Vit D
190
Tocopherol ; mild hemolytic anemia
Vit E
191
Phylloquinone / menaquinone ; hemorrhage or bruising
Vit K
192
Water-soluble vitamins
Vit C and B-complex (1,2,3,5,6,7,9,12)
193
Ascorbic acid ; scurvy
Vit C
194
Thiamine ; Beri-beri
Vit B1
195
Riboflavin ; angular stomatitis
Vit B2
196
Niacin ; pellagra
Vit B3
197
Pantothenic acid ; paresthesia
Vit B5
198
Pyridoxine ; facial seborrhea
Vit B6
199
Biotin ; Dermatitis
Vit B7
200
Folic acid ; megaloblastic anemia, neural tube defects
Vit B9
201
Cyanocobalamin ; megaloblastic anemia
Vit B12
