Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

AMT MT Exam > Review Cards - Clinical Chemistry > Flashcards

Review Cards - Clinical Chemistry Flashcards

(756 cards)

Start Studying
1
Q

Reference range: Bilirubin, total

A

0.2-1 mg/dL

SI units: 3.4-17.1 umol/L

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Reference range: BUN

A

6-20 mg/dL

SI units: 2.1-7.1 mmol/L

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Reference range: Calcium, total

A

8.6-10 mg/dL

SI units: 2.15-2.5 mmol/L

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Reference range: Chloride

A

98-107 mEq/L

SI units: 98-107 mmol/L

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Reference range: Creatinine

A

0.6-1.2 mg/dL

SI units: 53-106 mmol/L

Values can vary between males and females

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Reference range: Glucose, fasting

A

70-99 mg/dL

SI units: 3.9-5.5 mmol/L

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Reference range: Potassium

A

3.5-5.1 mEq/L

SI units: 3.5-5.1 mmol/L

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Reference range: Potassium

A

3.5-5.1 mEq/L

SI units: 3.5-5.1 mmol/L

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Reference range: Sodium

A

136-145 mEq/L

SI units: 136-145 mmol/L

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Reference range: Total protein

A

6.4-8.3 g/dL

SI units: 64-83 g/L

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Reference range: Uric acid

A

Male: 3.5-7.2 mg/dL
Female: 2.6-6 mg/dL

SI units:
Male: 208-428 umol/L
Female: 155-357 umol/L

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Diurnal variation - analytes affected?

A

Increased in AM: ACTH, cortisol, iron

Increased in PM: growth hormone, PTH, TSH

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Day-to-day variation - analytes affected?

A

> =20% for alanine aminotransferase (ALT), bilirubin, creatinine kinase, steroid hormones, triglycerides

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Recent food ingesting - analytes affected?

A

Increased: glucose, insulin, gastrin, triglycerides, sodium, uric acid, iron, lactate dehydrogenase, calcium

Decreased: chloride, phosphate, potassium

Fasting required: fasting glucose, triglycerides, lipid panel

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Alcohol - analytes affected?

A

Decreased: glucose

Increased: cholesterol, gamma glutamyl transferase (GGT)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Posture - analytes affected?

A

Increased: albumin, cholesterol, calcium

(when standing)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Activity - analytes affected?

A

Increased in ambulatory patients: creatinine kinase (CK)

Increased with exercise: potassium, phosphate, lactic acid, creatinine, protein, CK, aspartate, aminotransferase (AST), LD

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Stress - analytes affected?

A

Increased: ACTH, cortisol, catecholamines

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Age, gender, race, drugs - analytes affected?

A

Various

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Use of isopropyl alcohol wipes to disinfect venipuncture site - effect?

A

can compromise blood alcohol determination

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

squeezing site of capillary puncture - effect?

A

increased potassium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

pumping fist during venipuncture - effect?

A

increased: potassium, lactic acid, calcium, phosphorus

decreased: pH

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Tourniquet >1 minute - effect?

A

increased: potassium, total protein, lactic acid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

IV fluid contamination - effect?

A

Increased: glucose, potassium, sodium, chloride (depending on IV)

Possible dilution of other analytes.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Incorrect anticoagulant or contamination from incorrect order of draw - effect?
K2EDTA: decreased calcium, magnesium increased potassium Sodium heparin: increased sodium if tube is not completely filled Lithium heparin: increased lithium Gels: some interfere with trace metals & certain drugs
26
Hemolysis - effect?
Increased potassium, magnesium, phosphorus, LD, AST, iron, ammonia (May be method dependent. Refer to reagent package inserts.)
27
Exposure to light - effect?
decreased bilirubin
28
Temperature between collection & testing - effect?
chilling required for lactic acid, ammonia, blood gases
29
Inadequate centrifugation - effect?
poor barrier formation in gel tubes can result in increased: potassium, LD, AST, iron, phosphorus
30
Recentrifugation of primary tubes - effect?
hemolysis Increased potassium
31
Delay in separating serum/plasma (unless gel tube is used) - effect?
Increased: ammonia, lactic acid, potassium, magnesium, LD Decreased: glucose (unless collected in fluoride)
32
Storage temperature - effect?
Decreased at RT: glucose (unless collected in fluoride) Increased at RT: lactic acid, ammonia Decreased at 4*C: LD Increased at 4*C: alkaline phosphatase (ALP)
33
Higher in plasma than serum
Total protein LD Calcium
34
Higher in serum than plasma
Potassium Phosphate Glucose CK Bicarbonate ALP Albumin AST Triglycerides
35
Higher in plasma than whole blood
Glucose
36
Higher in capillary blood than venous blood
Glucose (in postprandial specimen) Potassium
37
Higher in venous blood than capillary blood
Calcium Total protein
38
Higher in RBCs than plasma
Potassium Phosphate Magnesium
39
Higher in plasma than RBCs
Sodium Chloride
40
Spectophotometry - principle?
A chemical reaction produces a colored substance that absorbs light of a specific wavelength. The amount of light absorbed is directly proportional to the concentration of the analyte.
41
Spectrophotometry - component parts?
1.Light source: a. Tungsten lamp - visible range b. Deuterium lamp - UV range 2. Monochromator - diffraction grating 3. Cuvette 4. Photodetector 5. Readout device
42
Atomic absorption spectrophotometry - principle?
Measures light absorbed by ground-state atoms. Hollow cathode lamp with cathode made of analyte produces wavelength specific for analyte. Used to measure TRACE METALS.
43
Atomic absorption spectrophotometry - component parts?
1. Hollow cathode lamp 2. Atomizer 3. Flame 4. Mixing chamber 5. Chopper 6. Monochromator 7. Detector 8. Readout device
44
Fluorometry - principle?
Atoms absorb light of a specific wavelength & emit light of a longer wavelength (lower energy) Detector at 90* to the light source so that only light emitted by the sample is measured. More sensitive than colorimetry. Used to measure DRUGS, HORMONES.
45
Fluorometry - component parts?
1. Light source - mercury or xenon arc lamp 2. Primary monochromator 3. Sample holder (quartz cuvettes) 4. Secondary monochromator 5. Detector 6. Readout device
46
Chemiluminescence - principle?
Chemical reaction that produces light. Usually involves oxidation of luminol, acridinium esters, or dioxetanes. Doesn't require excitation radiation or monochromators like fluorometry. Extremely sensitive. Used for immunoassays.
47
Chemiluminescence - component parts?
1. Reagent probes 2. Sample & reagent cuvettes 3. Photomultiplier tube 4. Readout device
48
Turbidimetry - principle?
Measures the reduction in light transmission by particles in suspension. Used to measure proteins in urine & CSF.
49
Nephelometry - principle?
Similar to turbidimetry, but light is measured at an angle from the light source. Used to measure antigen-antibody reactions.
50
Turbidimetry - component parts?
1. Light source 2. Lens 3. Cuvette 4. Photodetector 5. Readout device
51
Nephelometry - component parts?
1. Light source 2. Collimator 3. Monochromator 4. Cuvette 5. Photodetector 6. Readout device
52
Visible light spectrum: 350-430 nm Color absorbed? Color transmitted (visible)?
Absorbed: Violet Transmitted: Yellow
53
Visible light spectrum: 430-475 nm Color absorbed? Color transmitted (visible)?
Absorbed: Blue Transmitted: Orange
54
Visible light spectrum: 475-495 nm Color absorbed? Color transmitted (visible)?
Absorbed: Blue-green Transmitted: Red-orange
55
Visible light spectrum: 495-505 nm Color absorbed? Color transmitted (visible)?
Absorbed: Green-blue Transmitted: Orange-red
56
Visible light spectrum: 505-555 nm Color absorbed? Color transmitted (visible)?
Absorbed: Green Transmitted: Red
57
Visible light spectrum: 555-575 nm Color absorbed? Color transmitted (visible)?
Absorbed: Yellow-green Transmitted: Violet-red
58
Visible light spectrum: 575-600 nm Color absorbed? Color transmitted (visible)?
Absorbed: Yellow Transmitted: Violet
59
Visible light spectrum: 600-650 nm Color absorbed? Color transmitted (visible)?
Absorbed: Orange Transmitted: Blue
60
Visible light spectrum: 670-700 nm Color absorbed? Color transmitted (visible)?
Absorbed: Red Transmitted: Green
61
Wavelengths used in Spectrophotometry: 220-380 nm Range? Common light source? Cuvette?
Range: near-ultraviolet Light source: deuterium or mercury arc Cuvette: Quartz (silica)
62
Wavelengths used in Spectrophotometry: 380-750 nm Range? Common light source? Cuvette?
Range: visible Light source: Incandescent tungsten OR tungsten-iodide Cuvette: Borosilicate
63
Wavelengths used in Spectrophotometry: 750-2,000 nm Range? Common light source? Cuvette?
Range: Near-infrared Light source: Incandescent tungsten OR tungsten-iodide Cuvette: Quartz (silica)
64
Separation of compounds based on different distribution between mobile phase & stationary phase
Chromatography
65
Thin-layer chromatography - components?
1. Sorbent-coated glass or plastic plate 2. Closed container 3. Solvent
66
Thin-layer chromatography - use?
Screening for drugs of abuse in urine
67
Thin-layer chromatography - how are substances identified?
by retention factor (R1) value - distance traveled by compound/distance traveled by solvent
68
High-performance liquid chromatography (HPLC) - components?
1. Solvent 2. Pump 3. Injection port 4. Column 5. Detector 6. Recorder
69
High-performance liquid chromatography - use?
separation of thermolabile compounds
70
High-performance liquid chromatography - how is concentration determined?
by peak height ratio (height of analyte peak/height of internal standard peak)
71
High-performance liquid chromatography - what can be used as a detector for definitive identification?
mass spectrometry (MS) (LC/MS)
72
Gas chromatography - components?
1. Gas 2. Injection port 3. Column 4. Oven 5. Detector 6. Recorder
73
Gas chromatography - use?
separation of volatile compounds or compounds that can be made volatile, e.g., therapeutic & toxic drugs
74
Gas chromatography - what are compounds identified by?
retention time (area of peak is proportional to concentration) MS can be used as detector for definitive ID (GC/MS).
75
Ion-selective electrodes - principle?
Potential difference between 2 electrodes is directly related to the concentration of the analyte.
76
Ion-selective electrodes - component parts?
1. Reference electrode 2. Indicator electrode 3. Liquid junction 4. Measuring device
77
Ion-selective electrodes - Use?
pH PCO2 PO2 Sodium Potassium Calcium Lithium Chloride
78
Osmometry - principle?
Determines osmolality based on freezing-point depression.
79
Measurement of the number of dissolved particles in solution, irrespective of molecular weight, size, density, or type.
Osmolality
80
Osmometry - component parts?
1. cooling bath 2. thermistor 3. probe 4. stirring wire 5. galvanometer
81
Osmometry - use?
Serum & urine osmolality
82
Electrophoresis - principle?
Separation of charged particles in an electrical field. Anions move to positively charged pole (anode); cations move to negatively charged pole (cathode). The greater the charge, the faster the migration.
83
Electrophoresis - component parts?
1. Power supply 2. Support medium 3. Buffer 4. Stain 5. Densitometer
84
Electrophoresis - use?
Serum protein electrophoresis Hemoglobin electrophoresis
85
Mass spectrometry - principle?
Generates multiple ions from the sample, then separates them according to their mass to charge ratio (m/z). Extremely sensitive and specific.
86
Mass spectrometry - component parts?
1. Ion source 2. Analyzer 3. Detector system
87
Mass spectrometry - use?
Drugs of abuse Newborn screening Hormones Vitamins Steroid analysis
88
Basic metabolic panel
Sodium Potassium Chloride CO2 Glucose Creatinine BUN Calcium
89
Comprehensive metabolic panel
Sodium Potassium Chloride CO2 Glucose Creatinine BUN Calcium Albumin Total protein ALP AST Bilirubin
90
Electrolyte panel
Sodium Potassium Chloride CO2
91
Hepatic function panel
Albumin ALT AST ALP Bilirubin (total & direct) Total protein
92
Lipid panel
Total cholesterol HDL LDL Cholesterol Triglycerides
93
Renal function panel
Sodium Potassium CO2 Glucose Creatinine BUN Calcium Albumin Phosphate
94
Glucose, fasting - reference range?
Normal: <100 mg/dL (5.6 mmol/L)
95
Hyperglycemia - clinical significance?
Diabetes mellitus Other endocrine disorders Acute stress Pancreatitis
96
analyte that is a major source of cellular energy
Glucose
97
Hypoglycemia - clinical significance?
Insulinoma Insulin-induced hypoglycemia Hypopituitarism
98
Is glucose increased or decreased at RT?
decreased
99
Which additive should be used when collecting blood for glucose to prevent glycolysis?
Sodium fluoride
100
Most common methods of determining glucose concentration?
glucose oxidase & hexokinase Hexokinase = more accurate due to fewer interfering substances
101
Cholesterol, total - Reference range?
Desirable: <150 mg/dL (5.2 mmol/L)
102
Cholesterol, total - clinical significance?
Limited value for predicting risk of coronary artery disease (CAD) by itself. Used in conjunction with HDL & LDL cholesterol.
103
Most common method for measuring total cholesterol?
Enzymatic methods
104
HDL cholesterol - reference range?
Desirable: >=60 mg/dL (1.5 mmol/L)
105
HDL cholesterol - clinical significance?
Appears to be inversely related to CAD.
106
Assays used to measure HDL cholesterol?
Homogenous assays - don't require pretreatment to remove non-HDL 1st reagent - blocks non-HDL 2nd reagent - reacts with HDL
107
LDL cholesterol - reference range?
Optimal: <100 mg/dL (2.6 mmol/L)
108
LDL cholesterol - clinical significance?
Risk factor for CAD
109
How is LDL concentration determined?
May be calculated from the Friedewald formula (if triglycerides are not >400 mg/dL) OR measured by direct homogenous assays.
110
Triglycerides - reference range?
Desirable: <150 mg/dL (1.7 mmol/L)
111
Triglycerides - clinical signfiicance?
Risk factor for CAD.
112
What is the main form of lipid storage?
Triglycerides
113
Methods used for measuring triglyceride levels?
Enzymatic methods using lipase. (Requires a fasting specimen)
114
Total protein - reference range?
6.4-8.3 g/dL 64-83 g/L
115
Increased total protein - clinical significance?
dehydration chronic inflammation multiple myeloma
116
Decreased total protein - clinical significance?
nephrotic syndrome malabsorption overhydration hepatic insufficiency malnutrition agammaglobulinemia
117
What concentration of total protein is associated with peripheral edema?
<4.5 g/dL
118
Method of measuring total protein?
Biuret method (Alkaline copper reagent reacts with peptide bonds)
119
Albumin - reference range?
3.5-5 g/dL 35-50 g/L
120
Decreased albumin - clinical significance?
dehydration
121
Increased albumin - clinical significance?
malnutrition liver disease nephrotic syndrome chronic inflammation
122
What is the largest fraction of plasma proteins?
Albumin
123
Where is albumin synthesized?
liver
124
What is the function of albumin?
regulates osmotic pressure
125
How is albumin measured?
dye binding, e.g., bromocresol green (BCG), bromocresol purple (BCP)
126
Microalbumin (performed on urine sample) - reference range?
30-300 mg/24 hr
127
What is microalbuminuria predictive of?
diabetic nephropathy
128
Microalbumin - clinical significance?
increased in diabetics at risk of nephropathy
129
detects albumin in urine earlier than dipstick protein
microalbumin
130
alternative to measuring microalbumin in a 24 hr urine sample
albumin-to-creatinine ratio on a random sample
131
hormone that decreases glucose levels
insulin
132
action of insulin
responsible for entry of glucose into cells; increases glycogenesis
133
hormones that increase glucose levels
Glucagon Cortisol Epinephrine Growth hormone Thyroxine
134
responsible for entry of glucose into cells; increases glycogenesis
insulin
135
insulin antagonist; increases gluconeogenesis
cortisol
136
promotes glycogenolysis & gluconeogenesis
epineprhine
137
insulin antagonist
growth hormone
138
increases glucose absorption from GI tract; stimulates glycogenolysis
thyroxine
139
Type I diabetes mellitus - cause?
autoimmune destruction of beta cells genetic predisposition - HLA-DR 3/4
140
absolute insulin deficiency; prone to ketoacidosis & diabetic complications
Type 1 DM
141
Type 2 diabetes mellitus - cause?
Insulin resistance in peripheral tissues. -insulin secretory defect of beta cells -associated with obesity
142
Gestational diabetes mellitus - cause?
placental lactogen inhibits action of insulin
143
GDM - risk to fetus?
death or neonatal complications - macrosomia, hypoglycemia, hypocalcemia, polycythemia, hyperbilirubinemia
144
When is GDM usually diagnosed?
during later 1/2 of pregnancy
145
Pre-diabetes - cause?
patients unable to utilize glucose efficiently but are not yet considered fully diabetic
146
Tests for DM - random plasma glucose Pre-diabetes? DM?
Pre-diabetes: none DM: >=200 mg/dL (>11.1 mmol/L)
147
When is a random plasma glucose test used?
only for use in patients with symptoms of hyperglycemia
148
Tests for DM - fasting plasma glucose (FPG) Pre-diabetes? DM?
Pre-diabetes: 100-125 mg/dL DM: >=126 mg/dL
149
Tests for DM - oral glucose tolerance tests (OGTT) Pre-diabetes? DM?
140-199 mg/dL - 2 hours post-glucose ingestion indicates pre-diabetes DM: Fasting >=95 mg/dL OR 1 hour >=180 mg/dL, OR 2 hr >=155 mg/dL
150
When is an OGTT test performed during pregnancy?
24-28 weeks gestation
151
Tests for DM - Hemoglobin A1C Pre-diabetes? DM?
Pre-diabetes: 5.7-6.4% DM: >=6.5%
152
gives estimate of glucose control over previous 2-3 months
hemoglobin A1C
153
When should a hemoglobin A1C not be used?
patients with hemoglobinopathies or abnormal RBC turnover
154
Typical laboratory findings in uncontrolled DM: Increased? Decreased?
Increased: 1. blood glucose 2. urine glucose 3. urine SG 4. glycohemoglobin 5. ketones (blood & urine) 6. anion gap 7. BUN 8. Osmolality (serum & urine) 9. Cholesterol 10. Triglycerides Decreased: 1. Bicarbonate 2. Blood pH
155
Metabolic syndrome - definition?
group of risk factors that seem to promote development of atherosclerotic cardiovascular disease & type 2 diabetes mellitus
156
Metabolic syndrome - risk factors?
decreased HDL-C increased LDL-C increased triglycerides increased blood pressure increased blood glucose
157
Aminoacidopathies - Phenylketonuria - cause?
deficiency of the enzyme that converts phenylalanine to tyrosine phenylpyruvic acid in blood & urine
158
Aminoacidopathies - Phenylketonuria - effect?
mental retardation
159
Aminoacidopathies - Phenylketonuria - urine?
"mousy" odor
160
Aminoacidopathies - Phenylketonuria - diagnosis?
Guthrie bacterial inhibition assay, HPLC, tandem mass spectrometry (MS/MS), fluorometric & enzymatic methods. All newborns are screened.
161
Aminoacidopathies - Tyrosinemia - cause?
disorder of tyrosine catabolism - tyrosine and its metabolites are excreted in urine
162
Aminoacidopathies - Tyrosinemia - effect?
Liver & kidney disease, death
163
Aminoacidopathies - Tyrosinemia - diagnosis?
MS/MS
164
Aminoacidopathies - Alkaptonuria - cause?
Deficiency of the enzyme needed in the metabolism of tyrosine & phenylalanine; buildup of homogentisic acid
165
Aminoacidopathies - Alkaptonuria - effect?
diapers stain black due to homogentisic acid in urine later in life - darkening of tissues, hip & back pain
166
Aminoacidopathies - Alkaptonuria - diagnosis?
Gas chromatography & mass spectroscopy
167
Aminoacidopathies - Maple syrup urine disease (MSUD) - cause?
enzyme deficiency leading to the buildup of leucine, isoleucine, and valine
168
Aminoacidopathies - Maple syrup urine disease (MSUD) - effect?
Burnt-sugar odor to urine, breath, & skin. Failure to thrive, mental retardation, acidosis, seizures, coma & death
169
Aminoacidopathies - Maple syrup urine disease (MSUD) - diagnosis?
Modified Guthrie test, MS/MS
170
Aminoacidopathies - Homocystinuria - cause?
deficiency in the enzyme needed for the metabolism of methionine; methionine & homocysteine buildup in plasma & urine
171
Aminoacidopathies - Homocystinuria - effect?
osteoporosis dislocated lenses in the eye mental retardation thromboembolic events
172
Aminoacidopathies - Homocystinuria - diagnosis?
Guthrie test, MS/MS, LC-MS/MS
173
Aminoacidopathies - Cystinuria - cause?
Increased excretion of cystine due to defect in renal reabsorption
174
Aminoacidopathies - Cystinuria - effect?
recurring kidney stones
175
Aminoacidopathies - Cystinuria - diagnosis?
test urine with cyanide nitroprusside: pos = red-purple color
176
Protein electrophoresis - rate of migration?
depends on size, shape, & charge of molecule
177
Protein electrophoresis - support medium?
cellulose acetate or agarose
178
Protein electrophoresis - buffer?
barbital buffer, pH 8.6
179
Protein electrophoresis - stains?
Ponceau S amido blue bromphenol blue Coomassie brilliant blue
180
Protein electrophoresis - charge?
At pH 8.6, proteins are negatively charged & move toward the anode
181
Protein electrophoresis - order of migration (fastest to slowest)?
Albumin alpha-1 globulin alpha-2 globulin beta globulin-1 beta globulin-2 gamma globulin
182
Protein electrophoresis - largest fraction?
albumin
183
Protein electrophoresis - electroendosmosis?
buffer flow toward cathode - causes gamma region to be cathodic to point of application
184
Protein electrophoresis - urine?
Must be concentrated first because of low protein concentration. Bence-Jones proteins migrate to the gamma region in urine electrophoresis.
185
Protein electrophoresis - CSF?
Must be concentrated first because o flow protein concentration. CSF has a prealbumin band.
186
Common serum protein electrophoresis patterns - normal
187
Common serum protein electrophoresis patterns - acute inflammation
Decreased albumin Increased alpha-1 & alpha-2
188
Common serum protein electrophoresis patterns - chronic infection
Increased alpha-1, alpha-2, and gamma
189
Common serum protein electrophoresis patterns - cirrhosis
Polyclonal increase (all fractions) in gamma with beta-gamma bridging
190
Common serum protein electrophoresis patterns - monoclonal gammopathy
Sharp increase in 1 immunoglobulin ("M spike"), decrease in other fractions
191
Common serum protein electrophoresis patterns - polyclonal gammopathy
Diffuse increase in gamma
192
Common serum protein electrophoresis patterns - hypogammaglobulinemia
decreased gamma
193
Common serum protein electrophoresis patterns - nephrotic syndrome
decreased albumin increased alpha-2
194
Common serum protein electrophoresis patterns - alpha-1-antitrypsin deficiency
decreased alpha-1
195
Common serum protein electrophoresis patterns - hemolyzed specimen
increased beta or unusual band between alpha-2 & beta
196
Common serum protein electrophoresis patterns - plasma
extra band (fibrinogen) between beta & gamma
197
List the nonprotein nitrogen compounds.
1. BUN 2. Creatinine 3. Uric acid 4. Ammonia
198
BUN - reference range?
8-26 mg/dL (2.1-7.1 mmol/L)
199
BUN - clinical significance?
Increased - kidney disease Decreased - overhydration or liver disease
200
How is BUN synthesized?
by the liver from ammonia
201
How is BUN excreted?
by the kidneys
202
BUN - reagent?
Urease
203
Which anticoagulants should not be used to collect a BUN sample?
sodium fluoride EDTA citrate ammonium heparin
204
How is BUN measured?
Utilizes urease reaction, measure decrease in absorbance at 340 nm
205
How should a BUN urine specimen be stored?
Dilute urine 1:20 or 1:50 & refrigerate or acidify
206
Creatinine - reference range?
0.6-1.2 mg/dL (53-106 mmol/L)
207
Creatinine - clinical significance?
Increased - kidney disease
208
waste product from dehydration of creatine (mainly in muscles)
creatinine
209
Creatinine - method of measurement?
Jaffe reaction (alkaline picrate) is nonspecific but kinetic version increases specificity; enzymatic methods are more specific. Dilute urine 1:100.
210
normal BUN:creatinine ratio
12-20
211
Uric acid - reference range?
Male: 3.5-7.2 mg/dL Female: 2.6-6 mg/dL
212
Uric acid - clinical significance?
increased - gout, renal failure, ketoacidosis, lactate excess, high nucleoprotein diet, leukemia, lymphoma, polycythemia decreased - administration of ACTH, renal tubular defects
213
What does elevated uric acid increase the risk of developing?
renal calculi
214
Uric acid - method of measurement?
analyzed with uricase method EDTA & fluoride interfere adjust urine pH to 7.5-8 to prevent precipitation
215
Ammonia - reference range?
19-60 mcg/dL
216
Ammonia - clinical significance?
Increased - liver disease, hepatic coma, renal failure, Reye syndrome
217
High levels of what nonprotein nitrogen compound are neurotoxic?
ammonia
218
What anticoagulant tubes should be used when testing for ammonia?
EDTA or heparin
219
Why should serum not be used when testing for ammonia?
serum may cause increased levels as NH3 is generated during clotting
220
How should specimens for ammonia be collected?
EDTA or heparin tubes Chilled immediately Analyzed ASAP Avoid contamination from ammonia from detergents or water
221
List the major electrolytes.
1. sodium 2. potassium 3. chloride 4. CO2, total
222
Sodium - reference range?
136-145 mmol/L
223
Sodium - clinical significance - hypernatremia
Increased intake IV administration hyperaldosteronism excessive sweating burns diabetes insipidus -causes tremors, irritability, confusion, coma
224
Sodium - clinical significance - hyponatremia
Renal or extrarenal loss (vomiting, diarrhea, sweating, burns) Increased extracellular fluid volume -causes weakness, nausea, altered mental status
225
What is the major extracellular cation?
Sodium
226
What electrolyte contributes almost half to plasma osmolality?
Sodium
227
Function of sodium in the body
maintains normal distribution of water & osmotic pressure
228
What are sodium levels regulated by?
aldosterone
229
Sodium- method of measurment
ion-selective electrode (ISE)
230
What is the normal sodium/potassium ratio in serum?
30:1
231
Potassium - reference range?
3.5-5.1 mmol/L
232
Potassium - clinical significance - hyperkalemia
increased intake decreased excretion crush injuries metabolic acidosis -can cause muscle weakness, confusion, cardiac arrhythmia, cardiac arrest
233
Potassium - clinical significance - hyperkalemia
increased GI or urinary loss use of diuretics metabolic alkalosis -can cause muscle weakness, paralysis, breathing problems, cardiac arrhythmia, death
234
What is the major intracellular cation?
potassium
235
What can cause a artificial increase in potassium?
squeezing site of capillary puncture prolonged tourniquet pumping fist during venipuncture contamination with IV fluid hemolysis prolonged contact with RBCs leukocytosis thrombocytosis
236
Why are serum potassium values 0.1-0.2 mmol/L HIGHER than plasma?
Due to release from platelets during clotting
237
Potassium - method of measurement
Ion selective electrode (ISE) with vancomycin membrane
238
Chloride - reference range?
98-107 mmol/L
239
Chloride - clinical significance - hyperchloremia
increased intake IV administration hyperaldosteronism excessive sweating burns diabetes insipidus excess loss of HCO3-
240
Chloride - clinical significance - hypochloremia
prolonged vomiting diabetic ketoacidosis aldosterone deficiency salt-losing renal diseases metabolic alkalosis compensated respiratory acidosis
241
What is the major extracellular ion?
Chloride
242
Function of chloride
helps maintain osmolality, blood volume, electric neutrality
243
What passively follows sodium?
Chloride
244
Chloride - method of measurement
ISE
245
What test is used for the diagnosis of cystic fibrosis?
Sweat chloride test
246
CO2, total - reference range
23-29 mmol/L
247
CO2, total - clinical significance - increased
metabolic alkalosis compensated respiratory acidosis
248
CO2, total - clinical significance - decreased
metabolic acidosis compensated respiratory alkalosis
249
In what form is most CO2?
>90% bicarbonate (HCO3-) -remainder is carbonic acid (H2CO3) & dissolved CO2
250
Function of HCO3-
maintain acid-base balance
251
Why should you keep a sample being tested for CO2 capped?
to prevent loss of CO2
252
CO2, total - method of measurement
ISE or enzymatic method
253
Magnesium - reference range
1.6-2.6 mg/dL
254
Magnesium - clinical significance - increased
renal failure increased intake (e.g., antacids) dehydration bone cancer endocrine disorders -can cause cardiac abnormalities, paralysis, respiratory arrest, coma
255
Magnesium - clinical significance - decreased
severe illness GI disorders endocrine disorders renal loss -can lead to cardiac arrhythmias, tremors, tetany, paralysis, psychosis, coma -rare in non-hospitalized patients
256
Function of magnesium
essential cofactor for many enzymes
257
What electrolyte is 10x more concentrated in RBCs?
magnesium
258
Which anticoagulants/additives should be avoided when collecting a specimen for magnesium? Why?
EDTA, citrate, oxalate -they bind magnesium
259
Does hemolysis affect magnesium test results?
yes
260
Calcium - reference range
Total: 8.6-10 mg/dL Ionized: 4.60-5.08 mg/dL
261
Calcium - clinical significance - increased
primary hyperparathyroidism cancer multiple myeloma -can cause weakness, coma, GI symptoms, renal calculi
262
Calcium - clinical significance - decreased
hypoparathyroidism malabsorption vitamin D deficiency renal tubular acidosis -leads to tetany (muscle spasms), seizures, cardiac arrhythmias
263
What is the most abundant mineral in the body?
calcium 99% in bones
264
What is calcium regulated by?
PTH vitamin D calcitonin
265
Magnesium - method of measurement
colorimetric methods
266
What anticoagulant/additives should be avoided when collecting a specimen for calcium? Why?
all except heparin -they bind calcium
267
Calcium (total) - method of measurement
Colorimetric methods
268
What is the biologically active form of calcium and a better indicator of calcium status?
ionized (free) calcium
269
Calcium (ionized) - method of measurement
ISE
270
What factors affect the results of calcium measurement?
pH temp
271
Phosphorus, inorganic (phosphate) - reference range
2.5-4.5 mg/dL
272
Phosphorus, inorganic (phosphate) - clinical significance - increased
renal disease hypoparathyroidism
273
Phosphorus, inorganic (phosphate) - clinical significance - decreased
hyperparathyroidism vitamin D deficiency renal tubular acidosis
274
What is the major extracellular anion?
Phosphorus
275
Where in the body is most phosphorus located?
bones
276
Function of phosphorus
component of nucleic acids and many coenzymes important reservoir of energy (ATP)
277
Phosphorus results are a limited value alone. What should results be correlated with?
calcium (normally a reciprocal relationship)
278
True or False. Phosphorus is higher in children than adults.
True
279
Which anticoagulants/additives interfere with phosphorus results?
citrate oxalate EDTA
280
Is phosphorus higher in RBCs or plasma?
RBCs
281
Does hemolysis affect phosphorus results?
yes
282
Lactate (lactic acid) - reference range
4.5-19.8 mg/dL
283
Lactate (lactic acid) - clinical significance
sign of decreased O2 to tissues
284
What is lactate (lactic acid) a byproduct of?
anaerobic metabolism
285
Lactate (lactic acid) - collection considerations
Best NOT to use a tourniquet. Patient should not make a fist. Collect in heparin & put on ice OR use fluoride to inhibit glycolysis.
286
Lactate (lactic acid) - method of measurement
enzymatic methods
287
Iron - reference range
Males: 65-175 mcg/dL Females: 50-170 mcg/dL
288
Iron- clinical significance - increased
iron overdose hemochromatosis sideroblastic anemia hemolytic anemia liver disease
289
Iron - clinical significance - decreased
iron deficiency anemia
290
What analyte is necessary for hemoglobin synthesis?
Iron
291
How is iron transported in the body?
by transferrin
292
Does hemolysis interfere with iron testing?
yes
293
Which anticoagulants/additives should be avoided when collecting a specimen for iron? Why?
Oxalate, citrate, EDTA -they bind iron
294
Why is an early morning specimen preferred for iron testing?
because of diurnal variation
295
Iron - method of measurement
Colorimetric methods
296
Total iron binding capacity (TIBC) - reference range
250-425 mcg/dL
297
Total iron binding capacity (TIBC) - clinical significance - increased
iron deficiency anemia
298
Total iron binding capacity (TIBC) - clinical significance - decreased
iron overdose hemochromatosis
299
Total iron binding capacity (TIBC) - method of measurement
Iron is added to saturate transferrin. The excess is removed. Then iron content is determined.
300
% saturation or transferrin saturation - reference range
20-50%
301
% saturation or transferrin saturation - clinical significance - increased
iron overdose hemochromatosis sideroblastic anemia
302
% saturation or transferrin saturation - clinical significance - decreased
iron deficiency anemia
303
% saturation or transferrin saturation - method of measurement
Calculated value.
304
Transferrin - reference range
200-360 mg/dL
305
Transferrin - clinical significance - increased
iron deficiency anemia
306
Transferrin - clinical significance - decreased
iron overdose hemochromatosis chronic infections malignancies
307
What is transferrin?
Complex of apotransferrin (protein that transports iron) and iron.
308
Transferrin - method of measurement
immunoassay
309
Ferritin - reference range
Males: 20-250 mcg/L Females: 10-120 mcg/L
310
Ferritin - clinical significance - increased
iron overload hemochromatosis chronic infections malignancies
311
Ferritin - clinical significance - decreased
iron deficiency anemia
312
What is the storage form of iron?
ferritin
313
rough estimate of body iron content
ferritin
314
Ferritin - method of measurement
immunoassay
315
List the factors that influence enzymatic reactions.
1. substrate concentration 2. enzyme concentration 3. pH 4. temperature 5. cofactors 6. inhibitors
316
Factors that influence enzymatic reactions - substrate concentration - first-order kinetics
[enzyme] > [substrate] Reaction rate is proportional to [substrate].
317
Factors that influence enzymatic reactions - substrate concentration - zero-order kinetics
[substrate] > [enzyme] Reaction rate is proportional to [enzyme].
318
Factors that influence enzymatic reactions - enzyme concentration
velocity of the reaction is proportional to [enzyme] as long as [substrate] > [enzyme]
319
Factors that influence enzymatic reactions - enzyme concentration - unit of measure
international unit (IU)
320
Factors that influence enzymatic reactions - enzyme concentration - enzyme catalytic activity measurement
the amount of enzyme that will catalyze 1 umol of substrate per minute under standardized conditions
321
Factors that influence enzymatic reaction - pH
extremes of pH may denature enzymes Most reactions occur at pH 7-8. Use buffers to maintain optimal pH.
322
Factors that influence enzymatic reactions - temperature
Increases of 10*C doubles the rate of reaction until around 40-50*C; then denaturation of enzyme may occur. 37*C is most commonly used in the US.
323
Factors that influence enzymatic reactions - cofactors
nonprotein organic molecules that participate in reactions. Must be present in excess.
324
Factors that influence enzymatic reactions - cofactors - organic
called coenzymes - may serve as 2nd substrate in the reaction (e.g., nicotinamide adenine nucleotide)
325
Factors that influence enzymatic reactions - cofactors - inorganic
called activators - either required for OR enhance reaction (e.g., chloride, magnesium)
326
Factors that influence enzymatic reactions - cofactors - reaction most commonly used in enzyme determinations
NAD <--> NADH (reduced form of NAD) NADH has absorbance at 340 nm; NAD does not.
327
Factors that influence enzymatic reactions - inhibitors
interfere with the reaction
328
Enzymes of clinical significance - Alkaline phosphatase (ALP) - location in body
almost all tissues
329
Enzymes of clinical significance - Alkaline phosphatase (ALP) - clinical significance - increased
liver disease bone disease biliary tract obstruction (higher levels than hepatocellular disorders - hepatitis, cirrhosis)
330
Enzymes of clinical significance - Alkaline phosphatase (ALP) - higher in what population?
children adolescents pregnant women healing bone fractures
331
Enzymes of clinical significance - Alkaline phosphatase (ALP) - optimal pH
pH = 9-10
332
Enzymes of clinical significance - AST - location in body
Many tissues. Highest in liver, heart, and skeletal muscle.
333
Enzymes of clinical significance - AST - clinical significance - increased
liver disease (marked increased in viral hepatitis) acute myocardial infarction (AMI) muscular dystrophy
334
Does hemolysis affect AST testing?
yes
335
Enzymes of clinical significance - AST - method of measurement
Pyridoxal-5-Phosphate (P5P) is added as a cofactor in chemical reaction (Method of Henry). P5P is one of the six active forms of B6 (activated in the liver).
336
Enzymes of clinical significance - ALT - location in the body
Liver, RBCs
337
Enzymes of clinical significance - ALT - clinical significance - increased
liver disease -marked increase in viral hepatitis
338
What enzyme is more specific for liver disease? A. ALP B. AST C. ALT D. GGT
C. ALT
339
What is the most common product in both ALT and AST chemical reactions?
glutamate
340
Enzymes of clinical significance - GGT - location in body
Liver, kidneys, pancreas
341
Enzymes of clinical significance - GGT - clinical significance - increased
all hepatobiliary disorders chronic alcoholism -highest levels with obstructive disorders
342
What enzyme is the most sensitive for all types of liver disease and is used by treatment centers to monitor abstention from alcohol? A. ALP B. AST C. ALT D. GGT
D. GGT
343
Enzymes of clinical significance - LD - location in body
All tissues. Highest in liver, heart, skeletal muscle, and RBCs
344
Enzymes of clinical significance - LD - clinical significance - increased
acute myocardial infarction (AMI) - LD 1 & 2 elevated liver disease - LD-5 elevated pernicious anemia (highest levels) - LD-1 elevated
345
What enzyme catalyzes lactic acid to pyruvic acid?
lactate dehydrogenase (LD)
346
Does hemolysis affect LD testing?
yes
347
What temperature should LD samples be stored at?
25*C (NOT 4*C)
348
Enzymes of clinical significance - CK - location in body
cardiac muscle (CK-MB isotope) skeletal muscle brain
349
Enzymes of clinical significance - CK - clinical significance - increased
AMI muscular dystrophy (highest levels)
350
What reaction does CK catalyze?
phosphocreatine + ADP <--> creatine + ADP
351
What enzyme is the most sensitive for skeletal muscle disease? A. LD B. CK C. AMS D. LPS
B. CK
352
Which factors can affect testing for CK? A. all anticoagulants, except heparin B. physical activity C. intramuscular injections D. All of the above
D. all of the above -physical activity and IM injections can cause an increase in CK -inhibited by all anticoagulants, except heparin
353
Which isotope of CK is used in the diagnosis of AMI?
CK-MB
354
Enzymes of clinical significance - Amylase (AMS) - location in body
salivary glands pancreas
355
Enzymes of clinical significance - Amylase (AMS) - clinical significance - increased
acute pancreatitis other abdominal diseases mumps
356
Enzymes of clinical significance - Amylase (AMS) - function
breaks down starch to simple sugars
357
Enzymes of clinical significance - Amylase (AMS) - levels in pancreatitis
Levels increased 2-12 hours after attack, peak at 24 hours, and return to normal in 3-5 days.
358
Enzymes of clinical significance - Lipase (LPS) - location in body
pancreas
359
Enzymes of clinical significance - Lipase (LPS) - clinical significance - increased
acute pancreatitis
360
Enzymes of clinical significance - Lipase (LPS) - function
breaks down triglycerides into fatty acids & glycerol
361
Enzymes of clinical significance - Lipase (LPS) - levels in pancreatitis
Usually parallel amylase, but may stay elevated longer. -more specific than amylase for pancreatic disease
362
Enzymes of clinical significance - Glucose-6-phosphate-dehydrogenase (G6PD) - location in body
RBCs
363
Enzymes of clinical significance - Glucose-6-phosphate-dehydrogenase (G6PD) - measurement
Measured in hemolysate of whole blood.
364
Enzymes of clinical significance - Glucose-6-phosphate-dehydrogenase (G6PD) - clinical significance
Inherited deficiency can lead to drug-induced hemolytic anemia.
365
Diagnostic enzymology - hepatocellular disorders
AST ALT LD
366
Diagnostic enzymology - biliary tract obstruction
ALP GGT
367
Diagnostic enzymology - skeletal muscle disorders
CK AST LD aldolase
368
Diagnostic enzymology - bone disorders
ALP
369
Diagnostic enzymology - acute pancreatitis
Amylase Lipase
370
Cardiac markers for diagnosis AMI - CK-MB - elevation after chest pain
4-6 hours
371
Cardiac markers for diagnosis AMI - CK-MB - duration of elevation
2-3 days
372
Cardiac markers for diagnosis AMI - CK-MB - sensitivity/specificity
not entirely specific for AMI
373
Cardiac markers for diagnosis AMI - CK-MB - methods of measurment
immunoassay
374
Cardiac markers for diagnosis AMI - CK-MB - most often used in combination with what other cardiac marker?
troponin
375
Cardiac markers for diagnosis AMI - Myoglobin - elevation after chest pain
1-4 hours
376
Cardiac markers for diagnosis AMI - Myoglobin - duration of elevation
18-24 hours
377
Cardiac markers for diagnosis AMI - Myoglobin - sensitivity/specificity
sensitive but not specific at all
378
Cardiac markers for diagnosis AMI - Myoglobin - method of measurement
immunoassay
379
Cardiac markers for diagnosis AMI - Cardiac troponins (cTnI or cTnT) - elevation after chest pain
3-10 hours
380
Cardiac markers for diagnosis AMI - Cardiac troponins (cTnI or cTnT) - duration of elevation
4-10 days
381
Cardiac markers for diagnosis AMI - Cardiac troponins (cTnI or cTnT) - sensitivity/specificity
high sensitivity & specificity
382
Cardiac markers for diagnosis AMI - Cardiac troponins (cTnI or cTnT) - method of measurement
immunoassay
383
What cardiac marker is considered the definitive marker for AMI?
troponin
384
Testing recommendations for drawing blood for cardiac markers
Draw at admission, at 6-9 hours, & at 12-24 hours, if previous results were not increased.
385
Which cardiac troponin is more specific, cTnI or cTnT?
cTnI
385
Which cardiac troponin is more specific, cTnI or cTnT?
cTnI
386
List cardiac tests used to diagnose heart failure.
B-type natriuretic peptide (BNP)
387
Cardiac tests - BNP - clinical significance
Released from the heart muscle of the left ventricle when fluid builds from heart failure. Acts on the kidneys to increase excretion of fluid.
388
List the cardiac tests used to assess risk of Coronary Artery Disease (CAD).
1. High-sensitivity CRP (hs-CRP) 2. Total cholesterol 3. HDL cholesterol 4. LDL cholesterol 5. Triglycerides
389
Tests to assess risk of CAD - High sensitivity CRP (hs-CRP) - clinical significance
Non-specific marker of inflammation. Best single marker for predicting cardiovascular events.
390
Tests to assess risk of CAD - High sensitivity CRP (hs-CRP) - why should it be tested on 2 occasions?
because of individual variability
391
Tests to assess risk of CAD - High sensitivity CRP (hs-CRP) - methods of measurement
Nephelometry Immunoassay
392
Tests to assess risk of CAD - Total cholesterol - clinical significance
Most often used in conjunction with HDL & LDL cholesterol. Desirable: <200 mg/dL
393
Tests to assess risk of CAD - HDL cholesterol - clinical significance
Low level are a risk factor. Desirable: >=60 mg/dL
394
Tests to assess risk of CAD - LDL cholesterol - clinical significance
Major cause of CAD. Primary target of therapy. Optimal: <100 mg/dL
395
Tests to assess risk of CAD - Triglycerides - clinical significance
Independent risk factor for CAD. Desirable level: <150 mg/dL
396
Primary lipid disorders - Lipoprotein Lipase Deficiency - laboratory findings
Extremely high triglyceride levels: 5,000-10,000 mg/dL Elevated plasma chylomicrons. Extremely "milky"-looking serum. Erupted xanthomas are common manifestations of disease.
397
Primary lipid disorders - Familial Combined Hyperlipidemia - laboratory findings
Triglycerides usually between 200-400 mg/dL. -further classified by which lipid is elevated
398
Primary lipid disorders - Familial Hypertriglyceridemia - laboratory findings
-moderate increase in plasma triglycerides -increased VLDL -sometimes decreased HDL -milky serum after overnight refrigeration
399
Primary lipid disorders - Familial Hypercholesterolemia - laboratory findings
-moderate increased in plasma LDL values (300=450 mg/dL) -defect in the LDL receptor pathway leads to deposits of LDL in skin, tendons, and arteries.
400
Primary lipid disorders - Tangier Disease (Hypoalphalipoproteinemia) - laboratory findings
-decreased or absent plasma HDL -orange-colored tonsils often present
401
Primary lipid disorders - Tangier Disease (Hypoalphalipoproteinemia) - pathophysiology
402
Primary lipid disorders - Lipoprotein Lipase Deficiency - pathophysiology
ApoC-2 or LPL deficiency
403
Primary lipid disorders - Familial Hypercholesterolemia - pathophysiology
LDL receptor deficiency
404
Primary lipid disorders - Familial Hypertriglyceridemia - pathophysiology
VLDL overproduction
405
Primary lipid disorders - Familial Combined Hyperlipidemia - pathophysiology
VLDL overproduction
405
Bilirubin metabolism
406
Total bilirbuin - reference range
0.2-1 mg/dL
407
Total bilirubin - clinical significance - increased
liver disease hemolysis HDN -in infants, >20 mg/dL is associated with brain damage (kernicterus)
408
What is total bilirubin the sum of?
the sum of conjugated, unconjugated, & delta bilirubin
409
What consideration should be taken when collecting a specimen for bilirubin testing?
Avoid hemolysis. Protect from sunlight.
410
Total bilirubin - method of measurement
Jendrassik-Grof method -diazo reagent -accelerator added so unconjugated bilirbuin reacts.
411
Total bilirubin - method of measurement (neonates)
Bilirubinometry - measures reflected light from skin using 2 wavelengths.
412
Conjugated bilirubin (direct bilirubin) - reference range
<0.8 mg/dL
413
Conjugated bilirubin (direct bilirubin) - clinical significance - increased
liver disease obstructive jaundice
414
Conjugated bilirubin (direct bilirubin) - composed of?
bilirubin monoglucuronide bilirubin diglucuronide & delta bilirubin (bound to albumin; only seen with significant hepatic obstruction)
415
Conjugated bilirubin (direct bilirubin) - method of measurement
Jendrassik-Grof method -diazo reagent -NO accelerator required
416
Unconjugated bilirubin (indirect bilirubin) - reference range
<0.2 mg/dL
417
Unconjugated bilirubin (indirect bilirubin) - clinical significance - increased
prehepatic, posthepatic, & some types of hepatic jaundice
418
Unconjugated bilirubin (indirect bilirubin) - method of measurement
Calculated value. Total bili - direct bili = unconjugated bili
419
Unconjugated vs. Conjugated bilirubin - bound to protein
Unconjugated - yes (albumin) Conjugated - no (except delta bili)
420
Unconjugated vs. Conjugated bilirubin - type of compound
Unconjugated - nonpolar Conjugated - polar
421
Unconjugated vs. Conjugated bilirubin - soluble in water?
Unconjugated - no Conjugated - yes
422
Unconjugated vs. Conjugated bilirubin - present in urine?
Unconjugated - no Conjugated - yes
423
Unconjugated vs. Conjugated bilirubin - reaction with diazotized sulfanilic acid
Unconjugated - indirect (only reacts in the presence of accelerator) Conjugated - direct (reacts without accelerator)
424
Unconjugated vs. Conjugated bilirubin - affinity for brain tissue (causes kernicterus)
Unconjugated - high Conjugated - Low
425
Differential Diagnosis of Jaundice - prehepatic jaundice
Total bili - increased Direct bili - normal Urine bilirubin - negative Urine urobilinogen - increased
426
Differential Diagnosis of Jaundice - hepatic jaundice
Total bilirubin - increased Direct bili - variable Urine bilirubin - variable Urine urobilinogen - decreased
427
Differential Diagnosis of Jaundice - post-hepatic jaundice
Total bilirubin - increased Direct bilirubin - increased Urine bilirubin - positive Urine urobilinogen - decreased
428
List the anterior pituitary hormones.
1. ACTH 2. FSH 3. GH 4. LH 5. Prolactin (PRL) 6. TSH
429
List the posterior pituitary hormones.
1. ADH 2. Oxytocin
430
Anterior pituitary hormone - ACTH - regulates?
production of adrenocortical hormones by the adrenal cortex -cortisol -androgens (progesterone, estrogen) -aldosterone
431
Anterior pituitary hormone - ACTH - regulated by?
corticotropin-releasing hormone (CRH) from the hypothalamus
432
Anterior pituitary hormone - ACTH - diurnal variation
highest levels in early a.m., lowest in the afternoon
433
Anterior pituitary hormone - ACTH - clinical significance
increased in Cushing's disease
434
Anterior pituitary hormone - ACTH - collection
Collect on ice. Store frozen.
434
Anterior pituitary hormone - FSH - regulates?
sperm & egg production
435
Anterior pituitary hormone - FSH - regulated by?
gonadotropin-releasing hormone (GHRH) from the hypothalamus
436
Anterior pituitary hormone - FSH - clinical significance
Sharp increase just before ovulation.
437
Anterior pituitary hormone - Growth hormone (GH) - regulates?
-Protein synthesis -Cell growth & division
438
Anterior pituitary hormone - Growth hormone (GH) - regulated by?
growth-hormone releasing hormone (GHRH) & somatostatin from the hypothalamus.
439
Anterior pituitary hormone - Growth hormone (GH) - clinical significance
Increased - gigantism, acromegaly Decreased - dwarfism
440
Anterior pituitary hormone - Growth hormone (GH) - clinical significance
Increased - gigantism, acromegaly Decreased - dwarfism
441
Anterior pituitary hormone - Luteinizing hormone (LH) - regulates?
-Maturation of follicles -Ovulation -Production of estrogen, progesterone, testosterone
442
Anterior pituitary hormone - Luteinizing hormone (LH) - regulated by?
gonadotropin-releasing hormone (GnRH) from the hypothalamus
443
Anterior pituitary hormone - Luteinizing hormone (LH) - clinical significance
Sharp increase just before ovulation
444
Anterior pituitary hormone - Luteinizing hormone (LH) - home tests
ELISA kits to detect ovulation
444
Anterior pituitary hormone - Prolactin (PRL) - regulates?
lactation
445
Anterior pituitary hormone - Prolactin (PRL) - regulated by?
prolactin-releasing hormone (PRF) & prolactin-inhibiting factor (PIF) from the hypothalamus
446
Anterior pituitary hormone - TSH - regulates?
production of T3 & T4 by the thyroid
447
Anterior pituitary hormone - TSH - regulated by?
thyrotropin-releasing hormone (TRH) from the hypothalamus
448
Anterior pituitary hormone - TSH - clinical significance
Increased - hypothyroidism Decreased - hyperthyroidism
448
Posterior pituitary - ADH - regulates?
Reabsorption of water in distal renal tubules
449
Posterior pituitary - ADH - where is it produced?
hypothalamus
450
Posterior pituitary - ADH - where is it stored?
posterior pituitary
451
Posterior pituitary - ADH - what is it's release stimulated by?
-increased osmolality -decreased blood volume -decreased blood pressure
452
Posterior pituitary - ADH - clinical significance
decreased in diabetes insipidus
453
Posterior pituitary - Oxytocin - regulates?
-uterine contractions during childbirth -lactation
454
Posterior pituitary - Oxytocin - where is it produced?
hypothalamus
455
Posterior pituitary - Oxytocin - where is it stored?
posterior pituitary
456
Thyroid hormones - Thyroxine (T4) - regulates?
-metabolism -growth -development
457
Which thyroid hormone is considered the principle thyroid hormone?
T4
458
Thyroid hormones - Thyroxine (T4) - contains how many atom of iodine?
4
459
Thyroid hormones - Thyroxine (T4) - regulated by?
TSH
460
Thyroid hormones - Thyroxine (T4) - most bound to?
thyroxine-binding globulin (TBG)
461
Thyroid hormones - Thyroxine (T4) - clinical significance
Increased - hyperthyroidism Decreased - hypothyroidism
461
Thyroid hormones - Triiodothyronine (T3) - regulates?
-metabolism -growth -development
462
Thyroid hormones - Triiodothyronine (T3) - how is most formed?
from deiodination of T4 by the tissues.
463
Thyroid hormones - Triiodothyronine (T3) - contains how many atoms of iodine?
3
464
Thyroid hormones - Triiodothyronine (T3) - regulated by?
TSH
465
Thyroid hormones - Triiodothyronine (T3) - clinical significance
Increased - hyperthyroidism Decreased - hypothyroidism
466
True or False. T3 is 4x-5x more potent than T4.
True
467
Thyroid hormones - Calcitonin - regulates?
inhibition of calcium resorption
468
Thyroid hormones - Calcitonin - clinical significance
important in diagnosis of thyroid cancer
469
Thyroid hormones - Calcitonin - clinical significance
important in diagnosis of thyroid cancer
470
Parathyroid hormone (PTH) - regulates?
calcium & phosphate
471
Parathyroid hormone (PTH) - primary hyperparathyroidism - laboratory findings
Increased PTH Increased calcium Decreased phosphate
472
Parathyroid hormone (PTH) - Hypoparathyroidism - laboratory findings
Decreased PTH Decreased calcium Increased phosphate
473
Parathyroid hormone (PTH) - primary hypoparathyroidism
474
Thyroid function testing - Primary hypothyroidism - laboratory findings
Increased TSH Decreased Free T4 (FT4) Decreased Free T3 (FT3)
475
Thyroid function testing - Secondary hypothyroidism - laboratory findings
Decreased or normal TSH Decreased Free T4 Decreased Free T3
476
Thyroid function testing - Hyperthyroidism - laboratory findings
Decreased TSH Increased Free T4 Increased Free T3
477
Thyroid function testing - T3 Thyrotoxicosis - laboratory findings
Decreased TSH Normal Free T4 Increased Free T3
478
Thyroid function testing - Primary vs. Secondary Hypothyroidism
479
List the adrenal hormones located in the adrenal cortex.
1. aldosterone 2. cortisol
480
List the adrenal hormones located in the adrenal medulla.
1. epinephrine 2. norepinephrine (adrenaline, noradrenaline)
481
Adrenal hormones - cortex - Aldosterone - regulates?
reabsorption of sodium in the renal tubules
482
Adrenal hormones - cortex - Aldosterone - clinical significance
Increased - causes hypertension due to water & sodium retention Decreased - leads to severe water & electrolyte abnormalities
483
Adrenal hormones - cortex - Cortisol - regulates?
-carbohydrate, fat, & protein metabolism -water & electrolyte balance -suppresses inflammatory & allergic reactions
484
Adrenal hormones - cortex - Cortisol - regulated by?
ACTH
485
Adrenal hormones - cortex - Cortisol - diurnal variation
Highest in a.m.
486
Adrenal hormones - cortex - Cortisol - Cushing syndrome
Increased cortisol Loss of diurnal variation
487
Adrenal hormones - cortex - Cortisol - Addison disease
Decreased cortisol
488
Adrenal hormones - medulla - Epinephrine, norepinephrine - regulates?
"Fight or flight syndrome." Stimulation of the sympathetic nervous system.
489
What is the primary hormone of the adrenal medulla?
epinephrine
490
Adrenal hormones - medulla - catecholamines
Epinephrine & norepinephrine
491
Adrenal hormones - medulla - epinephrine & norepinephrine - metabolites
metanephrines => vanilylmandelic acid (VMA)
492
Adrenal hormones - medulla - epinephrine & norepinephrine - clinical significance
Increased with pheochromocytoma (rare catecholamine producing tumor)
493
Adrenal hormones - medulla - epinephrine & norepinephrine - tests
plasma & urine catecholamines & metanephrines urine VMA
494
Reproductive hormones - ovaries - estrogens - regulates?
-development of female reproductive organs & secondary sex characteristics -regulation of the menstrual cycle -maintenance of pregnancy
495
What is the major estrogen produced by the ovaries (and most potent)?
Estradiol (E2) (also produced in the adrenal cortex)
496
Reproductive hormones - ovaries - progesterone - regulates?
preparation of uterus for ovum implantation and maintenance of pregnancy
497
Reproductive hormones - ovaries - progesterone - also produced by?
the placenta
498
Reproductive hormones - ovaries - progesterone - metabolite
pregnanediol
499
Reproductive hormones - ovaries - progesterone - clinical significance
useful in infertility studies & to assess placental function
500
Reproductive hormones - placenta - estrogen (estriol) - regulates?
no hormonal activity
501
Reproductive hormones - placenta - estrogen (estriol) - clinical significance
used along with AFP, hCG, and inhibin A as part of the Quadrapole (Quad) screen to monitor fetal growth and development
502
Reproductive hormones - placenta - progesterone - regulates?
maintenance of pregnancy
503
Reproductive hormones - placenta - human chorionic gonadotropin (hCG) - regulates?
-progesterone production by the corpus luteum during early pregnancy -development of fetal gonads
504
Reproductive hormones - placenta - human chorionic gonadotropin (hCG) - clinical significance
-pregnancy -gestational trophoblastic disease (e.g., hydatidiform mole) -testicular tumor -other hCG-producing tumors
505
Reproductive hormones - placenta - inhibin A - regulates?
hormone made by the placenta - inhibits secretion of FSH by anterior pituitary
506
Reproductive hormones - placenta - inhibin A - clinical significance
part of Quad screen - monitor fetal growth and development -high levels seen with Down syndrome
507
Reproductive hormones - testes - testosterone - regulates?
development of male reproductive organs & secondary sex characteristics
508
Reproductive hormones - testes - testosterone - metabolites
-estradiol -dihydrotestosterone (DHT)
509
Pancreatic hormones - insulin - regulates?
carbohydrate metabolism
510
Pancreatic hormones - insulin - where is it produced?
produced in the beta cells of the islets of Langerhans
511
Pancreatic hormones - insulin - functions?
decreases plasma glucose levels by increasing movement of glucose into the cells for metabolism
512
Pancreatic hormones - insulin - clinical significance
Decreased in diabetes mellitus. Increased with insulinoma and hypoglycemia.
513
Pancreatic hormones - glucagon - regulates?
glycogenolysis gluconeogenesis lipolysis
514
Pancreatic hormones - glucagon - where is it produced?
produced in the alpha cells of the islets of Langerhans
515
Pancreatic hormones - glucagon - function
increases plasma glucose levels
516
Endocrine disorders - Addison Disease - laboratory findings
-decreased cortisol -decreased aldosterone -increased ACTH -decreased sodium -increased potassium
517
Endocrine disorders - Addison Disease - endocrine gland affected
adrenal cortex
518
Endocrine disorders - Addison Disease - diagnosis
-SCREEN for primary adrenal insufficiency with morning plasma cortisol -CONFIRMATION: decreased response to cosyntropin stimulation
519
Endocrine disorders - Addison Disease - common symptoms
-low blood pressure -darkening of the skin
520
Endocrine disorders - Cushing Disease - laboratory findings
-increased cortisol -increased ACTH
521
Endocrine disorders - Cushing Disease - endocrine gland affected
tumor of the pituitary gland
522
Endocrine disorders - Cushing Disease - diagnosis
CONFIRM: overnight dexamethasone suppression test
523
Endocrine disorders - Acromegaly - laboratory findings
increased growth hormone
524
Endocrine disorders - Acromegaly - endocrine gland affected
pituitary gland
525
Endocrine disorders - Acromegaly - diagnosis
CONFIRM: oral glucose tolerance test - growth hormone will remain abnormally elevated
526
Endocrine disorders - Diabetes insipidus - laboratory findings
-elevated plasma sodium -elevated plasma osmolality -decreased urine osmolality
527
Endocrine disorders - Diabetes insipidus - endocrine gland affected
hypothalamus OR kidneys
528
Endocrine disorders - Diabetes insipidus - pathophysiology
Deficient production or action of ACTH
529
Endocrine disorders - Diabetes insipidus - symptoms
polyuria polydipsia
530
Endocrine disorders - Pheochromocytoma - laboratory findings
-elevated plasma AND catecholamines (epinephrine & norepinephrine) -elevated plasma AND metanephrines -elevated urine VMA
531
Endocrine disorders - Pheochromocytoma - common symptoms
-unexplained high blood pressure -headaches -sweating
532
Endocrine disorders - Hyperprolactinemia - laboratory findings
elevated plasma prolactin
533
Endocrine disorders - Hyperprolactinemia - endocrine gland affected
pituitary gland
534
Endocrine disorders - Pheochromocytoma - endocrine gland affected
adrenal medulla
535
Endocrine disorders - Hyperprolactinemia - hook effect
falsely decreased results, immunoassay
536
Endocrine disorders - Hyperprolactinemia - falsely elevated results
macroprolactin
537
lowest concentration of drug in blood that will produce desired effect
minimum effective concentration (MEC)
538
lowest concentration of drug in blood that will produce an adverse response
minimum toxic concentration (MTC)
539
ratio of MTC to MEC
therapeutic index
540
lowest concentration of drug measured in blood; reached just before the next scheduled dose; shouldn't fall below MEC
trough
541
highest concentration of drug measured in blood; drawn immediately on achievement of steady state; should not exceed MTC
peak
542
amount of drug absorbed & distributed = amount of drug metabolized & excreted; usually reached after 5-7 half lives
steady state
543
the time required for the concentration of a drug to be decreased by half
half-life
544
the rates of absorption, distribution, biotransformation, & excretion
pharmacokinetics
545
Therapeutic drug groups - salicylates, acetaminophen
analgesics
546
Therapeutic drug groups - phenobarbital
antiepileptics
547
Therapeutic drug groups - phenytoin
antiepileptics
548
Therapeutic drug groups - valproic acid
antiepileptics
549
Therapeutic drug groups - carbamazepine
antiepileptics
550
Therapeutic drug groups - ethosuximide
antiepileptics
551
Therapeutic drug groups - felbamate
antiepileptics
552
Therapeutic drug groups - gabapentin
antiepileptics
553
Therapeutic drug groups - lamotrigine
antiepileptics
554
Therapeutic drug groups - methotrexate
antineoplastics
555
Therapeutic drug groups - aminoglycosides (amikacin, gentamicin, kanmycin, tobramycin), vancomycin
antibiotics
556
Therapeutic drug groups - digoxin
cardioactives
557
Therapeutic drug groups - disopyramide
cardioactives
558
Therapeutic drug groups - procainamide
cardioactives
559
Therapeutic drug groups - quinidine
cardioactives
560
Therapeutic drug groups - tricyclic antidepressants
psychoactives
561
Therapeutic drug groups - lithium
psychoactives
562
Therapeutic drug groups - cyclosporine
immunosuppressants
563
Therapeutic drug groups - tacrolimus (FK-506)
immunosuppressants
564
Toxic agents - ethanol - analytic method
-gas chromatography -enzymatic methods
565
Toxic agents - carbon monoxide - analytic method
-differential spectrophotometry (cooximeter) -gas chromatography
566
Toxic agents - arsenic - analytic method
atomic absorption
567
Toxic agents - lead - analytic method
atomic absorption
568
Toxic agents - pesticides - analytic method
measurement of serum pseudocholinesterase
569
Toxic agents - methanol - analytic method
gas chromatography
570
Drugs of abuse urine screen - drugs routinely tested
1. amphetamines 2. barbiturates 3. benzodiazepines 4. cannabinoids 5. cocaine 6. methadone 7. opiates 8. phencyclidine (PCP) 9. tricyclic antidepressants
571
Drugs of abuse urine screen - adulterated urine
value outside physiological range or presence of a substance that isn't found in human urine -pH <3 or >=11 -nitrite >=500 mg/dL -presence of chromium, halogens (bleach, iodine, fluoride), glutaraldehyde, pyridine, or surfactant
572
Drugs of abuse urine screen - substituted urine
values that aren't consistent with normal human urine -creatine <2 mg/dL -specific gravity <=1.0010 or >=1.0200
573
Drugs of abuse urine screen - diluted urine
creatine and specific gravity lower than expected for normal human urine -creatine >=2 mg/dL but <=20mg/dL -specific gravity >=1.0010 but <=1.0030
574
Drugs of abuse urine screen - method of measurement
immunoassay
575
Drugs of abuse urine screen - confirmation
mass spectrometry
576
Common tumor markers - alpha-Fetoprotein (AFP) - type of cancer for which marker is most often diagnosed
Liver
577
Common tumor markers - alpha-Fetoprotein (AFP) - clinical use
-aid diagnosis -monitor therapy -detect recurrence
578
Common tumor markers - alpha-Fetoprotein (AFP) - produced by?
fetal liver
579
Common tumor markers - alpha-Fetoprotein (AFP) - clinical significance
increased: -certain tumors -hepatitis -pregnancy
580
Common tumor markers - CA 15-3 and CA 27.29 - type of cancer for which marker is most often used
breast
581
Common tumor markers - CA 15-3 and CA 27.29 - clinical use
-stage disease -monitor therapy -detect recurrence
582
Common tumor markers - CA 15-3 and CA 27.29 - clinical significance
-breast cancer -can be increased with other cancers & non-cancerous conditions
583
Common tumor markers - CA 19-9 - type of cancer for which marker is most often used
pancreatic
584
Common tumor markers - CA 19-9 - clinical use
-stage disease -monitor therapy -detect recurrence
585
Common tumor markers - CA 19-9 - clinical significance
-pancreatic cancer -can be increased with other cancers & non-cancerous conditions
586
Common tumor markers - CA 125 - type of cancer for which marker is most often used
ovarian
587
Common tumor markers - CA 125 - clinical use
-aid diagnosis -monitor therapy -detect recurrence
588
Common tumor markers - CA 125 - clinical significance
-ovarian cancer -can be increased with other cancers & gynecological conditions
589
Common tumor markers - carcinoembryonic antigen (CEA) - type of cancer for which marker is most often used
colorectal
590
Common tumor markers - carcinoembryonic antigen (CEA) - type of antigen
fetal antigen re-expressed in tumors
591
Common tumor markers - carcinoembryonic antigen (CEA) - clinical use
-monitor therapy -detect recurrence
592
Common tumor markers - carcinoembryonic antigen (CEA) - clinical significance
-colorectal cancer -can be increased with other cancers, non-cancerous conditions, & in smokers
593
Common tumor markers - hCG - type of cancer for which marker is most often used
-ovarian & testicular cancers -gestational trophoblastic diseases
594
Common tumor markers - hCG - clinical use
-aid diagnosis -monitor therapy -detect recurrence
595
Common tumor markers - hCG - clinical significance
-ovarian cancer -testicular cancer -gestational trophoblastic diseases -pregancy
596
Common tumor markers - Prostate-specific antigen (PSA) - type of cancer for which marker is most often used
prostate
597
Common tumor markers - Prostate-specific antigen (PSA) - clinical use
-screening -aid diagnosis -monitor therapy -detect recurrence
598
Which tumor marker is the most widely used?
PSA
599
Common tumor markers - Prostate-specific antigen (PSA) - screening asymptomatic men is controversial
-some men with prostate cancer don't have increased PSA -PSA can be increased in other conditions
600
Common tumor markers - Prostate-specific antigen (PSA) - free PSA
may be helpful when PSA is borderline
601
Common tumor markers - Prostate-specific antigen (PSA) - free PSA
may be helpful when PSA is borderline
602
Common tumor markers - Thyroglobulin - type of cancer for which marker is most often used
thyroid
603
Common tumor markers - Thyroglobulin - clinical use
-monitor therapy -detect recurrence
604
Common tumor markers - Thyroglobulin - clinical significance
-thyroid cancer -increased in other thyroid diseases
605
Common tumor markers - Thyroglobulin - what should be measured at the same time?
antithyroglobulin antibodies
606
-Log[H+] or log 1/[H+]
pH
607
a chemical that can yield H+; proton donor; pH <7
acid
608
a chemical that can accept H+ or yield OH-; pH >7
base
609
a weak acid & its salt or conjugate base; minimizes changes in pH
buffer
610
What buffer is the most important one for maintaining blood pH? A. phosphates B. bicarbonate/carbonic acid C. proteins D. hemoglobin
B. bicarbonate/carbonic acid H+ + HCO3- <==> H2CO3 <==> H20 + CO2
611
HCO3-; second largest fraction of anions; proton acceptor or base; equal to total CO2 - 1
bicarbonate
612
What is bicarbonate (HCO3-) regulated by?
kidneys
613
H2CO3; proton donor or weak acid; equal to PCO2 x 0.03
carbonic acid
614
What is carbonic acid (H2CO3) regulated by?
lungs
615
all forms of CO2
total CO2 (HCO3- + H2CO3 + dissolved CO2)
616
partial pressure of CO2
PCO2
617
What is PCO2 directly related to?
the amount of dissolved CO2
618
Henderson-Hasselbalch equation
pH = 6.1 + log ([HCO3-]/[H2CO3]) OR 6.1 + log (HCO3-/PCO2) x 0.03
619
Acidosis (acidemia) - laboratory findings
-blood pH <7.38 -decreased HCO3-:H2CO3 ratio (normal is 20:1)
620
Acidosis (acidemia) - causes
1. decreased HCO3- (metabolic acidosis) 2. increased H2CO3 (respiratory acidosis)
621
Alkalosis (alkalemia) - laboratory findings
-blood pH >7.42 -increased HCO3-:H2CO3 ratio (normal 20:1)
622
Alkalosis (alkalemia) - causes
1. increased HCO3- (metabolic alkalosis) 2. decreased H2CO3 (respiratory alkalosis)
623
What is compensated acidosis or alkalosis?
when compensatory mechanisms have succeeded in returning the 20:1 ratio & pH returns to normal. -kidneys compensate for respiratory problems -lungs compensate for metabolic problems
624
Acid-Base imbalances - Respiratory acidosis
pH - decreased PCO2 - increased HCO3- - normal Compensation: kidneys retain HCO3-, excrete H+
625
Acid-Base imbalances - Metabolic acidosis
pH - decreased PCO2 - normal HCO3- - decreased Compensation: hyperventilation (blow off CO2)
626
Acid-Base imbalances - Respiratory alkalosis
pH - increased PCO2 - decreased HCO3- - normal Compensation: kidneys excrete HCO3-, retain H+
627
Acid-Base imbalances - Metabolic alkalosis
pH - increased PCO2 - normal HCO3- - increased Compensation: hypoventilation (retain CO2)
628
low O2 content in arterial blood
hypoxemia
629
lack of O2 at cellular level
hypoxia
630
barometric pressure x % gas concentration
partial pressure
631
partial pressure of CO2 expressed in mm of Hg
PCO2 -directly related to the amount of dissolved CO2 -measure of the respiratory component (inversely proportional to respiration)
632
partial pressure of O2
PO2 -assesses pulmonary function
633
graph showing relationship between oxygen saturation & PO2
oxygen dissociation curve
634
provides information about hemoglobin's affinity for O2
oxygen dissociation curve
635
phosphate compound in RBCs that affects O2 dissociation curve
2,3-Diphosphoglycerate (2,3-DPG)
636
low levels of 2,3-Diphosphoglycerate (2,3-DPG)
inhibit release of O2 to tissues
637
amount of O2 that is combined with hemoglobin, expressed as % of amount of O2 that can be combined with hemoglobin
oxygen saturation 1 g of hemoglobin can combine with 1.34 mL of O2
638
partial pressure of O2 at which hemoglobin saturation is 50%
P50
639
low value of P50
increased O2 affinity (shift to the left in O2 dissociation curve)
640
high value of P50
decreased O2 affinity (shift to the right in O2 dissociation curve)
641
Blood Gas Parameters - pH - measurement of?
[H+]
642
Blood Gas Parameters - pH - derivation
pH electrode on blood gas analyzer
643
Blood Gas Parameters - pH - reference range
7.35-7.45
644
Blood Gas Parameters - PCO2 - measurement of?
partial pressue of CO2
645
Blood Gas Parameters - PCO2 - derivation
PCO2 electrode on blood gas analyzer
646
Blood Gas Parameters - PCO2 - reference range
35-45 mm Hg
647
Blood Gas Parameters - PO2 - measurement of?
partial pressure of O2
648
Blood Gas Parameters - PO2 - derivation
PO2 electrode on blood gas analyzer
649
Blood Gas Parameters - PO2 - reference range
80-100 mm Hg
650
Blood Gas Parameters - HCO3- - measurement of?
bicarbonate
651
Blood Gas Parameters - HCO3- - derivation
calculated value on blood gas analyzer
652
Blood Gas Parameters - HCO3- - reference range
22-26 mmol/L
653
Blood Gas Parameters - total CO2 - measurement of?
bicarbonate + carbonic acid
654
Blood Gas Parameters - total CO2 - derivation
calculated value on blood gas analyzer
655
Blood Gas Parameters - total CO2 - reference range
23-27 mmol/L
656
Blood Gas Parameters - base excess - measurement of?
-metabolic component of acid-base status -difference between titratable bicarbonate of sample & that of normal blood sample
657
Blood Gas Parameters - base excess - derivation
calculated value on blood gas analyzer
658
Blood Gas Parameters - base excess - reference range
-2 to +2 mEq/L *negative values indicate base deficit
659
Blood Gas Parameters - oxygen saturation - measurement of
amount of oxygenated hemoglobin
660
Blood Gas Parameters - oxygen saturation - derivation
measured by oximeter
661
Blood Gas Parameters - oxygen saturation - reference range
94% - 100%
662
Blood Gas Instrumentation - pH electrode - description
H+-sensitive glass electrode containing Ag/AgCl wire in electrolyte of known pH & reference (calomel) electrode (Hg/Hg2Cl2) -measurement is potentiometric (change in voltage indicates activity of analyte)
663
Blood Gas Instrumentation - pH electrode - measures?
[H+]
664
Blood Gas Instrumentation - pH electrode - calibration
2 phosphate buffers of known pH -store at RT -don't expose to air
665
Blood Gas Instrumentation - PCO2 electrode - description
pH electrode covered with membrane permeable to CO2, with bicarbonate buffer between membrane & electrode -measure is potentiometric - change in voltage indicates activity of analyte
666
Blood Gas Instrumentation - PCO2 electrode - measures?
dissolved CO2
667
Blood Gas Instrumentation - PCO2 electrode - calibration
2 gases of known PCO2
668
Blood Gas Instrumentation - PO2 electrode (Clark electrode) - measures?
dissolved O2
669
Blood Gas Instrumentation - PO2 electrode - calibration
2 gases of known PO2
670
Blood Gas Instrumentation - PO2 - description
Platinum cathode & Ag/AgCl anode covered with semipermeable membrane. -measurement is amperometric - amount of current flow is indication of O2 present
671
Blood Gas Instrumentation - Co-oximeter - description
-spectrophotometer that reads absorbance or resistance at isobestic point (wavelength where reduced & oxyhemoglobin have same absorbance or reflectance, e.g., 805 nm) AND -differential point (wavelength where reduced & oxyhemoglobin have different absorbance or reflectance, e.g., 650 nm)
672
Blood Gas Instrumentation - Co-oximeter - measures?
oxygen saturation -some also measure carboxyhemoglobin, methemoglobin, & sulfhemoglobin by using additional wavelengths
673
Blood Gas Instrumentation - Co-oximeter - calibration
calibration curve prepared from specimens with 0% & 100% oxygen saturation
674
Sources of error in arterial blood gases - hyperventilation - effect
-decreased PCO2 -increased pH -increased PO2
675
Sources of error in arterial blood gases - specimen exposed to air - effect
-decreased PCO2 -increased pH -increased PO2
676
Sources of error in arterial blood gases - specimen at RT >30 minutes - effect
-increased PCO2 -decreased pH -decreased PO2
677
Albumin/Globulin (AG) ratio - calculation
678
Albumin/Globulin (AG) ratio - normal range
1-2.5
679
Albumin/Globulin (AG) ratio - clinical significance
reversed A/G ratio with multiple myeloma, liver disease
680
Amylase:creatinine clearance ratio - calculation
681
Amylase:creatinine clearance ratio - normal range
2%-5%
682
Amylase:creatinine clearance ratio - clinical significance
increased - acute pancreatitis decreased - macroamylasemia
683
Anion gap - calculation
684
Anion gap - normal range
7-16
685
Anion gap - normal range
10-20
686
difference between unmeasured anions and unmeasured cations
anion gap
687
Anion gap - clinical significance - increased
-renal failure -diabetic acidosis -lactic acidosis -methanol, ethanol, ethylene glycol, or salicylate poisoning -laboratory error
688
Anion gap - all determinations are increased or decreased
possible instrument error in 1 of the determinations
689
True or False. Anion gap cannot be a negative number.
True
690
BUN-to-creatinine ratio - calculation
691
BUN-to-creatinine ratio - normal range
10-20
692
BUN-to-creatinine ratio - clinical significance - renal disease
normal ratio
693
BUN-to-creatinine ratio - clinical significance - pre-renal conditions
increased ratio with increased BUN & normal creatinine
694
BUN-to-creatinine ratio - clinical significance - post-renal conditions
increased ratio with increased creatinine
695
BUN-to-creatinine ratio - clinical significance - decreased ratio
decreased ratio with decreased urea production (e.g., severe liver disease, decreased protein intake)
696
Creatinine clearance - calculation
697
Creatinine clearance - normal range
Males: 97-137 mL/min Females: 88-128 mL/min
698
Creatinine clearance - clinical significance
decreased in renal disease (early indicator)
699
Indirect (unconjugated) bilirubin - calculation
700
Indirect (unconjugated) bilirubin - normal range
<0.2 mg/dL
701
Indirect (unconjugated) bilirubin - clinical significance
increased in pre-hepatic, post-hepatic, & some type of hepatic jaundice
702
LDL cholesterol - calculation
Friedewald formula
703
LDL cholesterol - normal range
Desirable level: <130 mg/dL
704
LDL cholesterol - clinical significance
Increased LDL cholesterol is associated with increased with of CAD.
705
LDL cholesterol - when are LDL levels not valid?
if triglycerides are >400 mg/dL
706
Calculated osmolality - calculation
707
Calculated osmolality - normal range
275-295 Osm/kg
708
What does osmolality measure?
concentration of solute
709
What contributes the most to osmolality?
electrolytes
710
Osmolality - clinical significance
Increased - dehydration, uremia, uncontrolled diabetes, alcohol or salicylate poisoning, excessive electrolyte IVs Decreased - excessive water intake
711
Osmolal gap - calculation
712
Osmolal gap - normal range
0-10 mOsm/kg
713
similar to anion gap but based on osmotically active solute concentration rather than the concentrations of ions
osmolal gap
714
Osmolal gap - clinical significance
>10 indicates abnormal concentration of unmeasured substance (e.g., isopropanol, methanol, acetone, ethylene glycol) -used to diagnose poisonings
715
Urine-to-serum osmolality - calculation
Urine osmolality/serum osmolality
716
Urine-to-serum osmolality - normal range
1-3
717
Urine-to-serum osmolality - clinical significance
decreased in renal tubular deficiency and diabetes insipidus
718
Beer's Law
719
A manual glucose assay gave the following results: Absorbance of 100 mg/dL standard = 0.3. Absorbance of patient = 0.4. What is the glucose concentration of the patient?
133 mg/dL Note: If a dilution is run, multiply the answer by the reciprocal of the dilution.
720
mg/dl to mEq/L - calculation
721
A calcium is reported as 10 mg/dL. What is the concentration in mEq/L? (Atomic weight of calcium = 40. Valence of calcium = 2+.)
5
722
mg/dL to mmol/L - calculation
723
A calcium is reported as 10 mg/dL. What is the concentration in mmol/L? (Atomic weight of calcium = 40. Valence of calcium is 2+.)
2.5
724
mEq/L to mmol/L - calculation
725
A calcium is reported as 5 mEq/L. What is the concentration in mmol/L? (Atomic weight of calcium = 40. Valence of calcium = 2+.)
2.5
726
Molarity (M) calculation
727
What is the molarity of a solution that contains 45 grams of NaCl per liter? (Atomic weights: Na = 23, Cl = 35.5)
0.77
728
Normality (N) calculation
729
What is the normality of a solution that contains 98 grams of H2SO4 per 500 mL? (Atomic weights: H = 1, S = 32, O = 16.)
4
730
% concentration formula
731
What is the concentration in % of a solution that contains 8.5 grams of NaCl per liter?
0.85%
732
Calculation for finding normality when given the molarity
733
What is the normality of a 3 M H2SO4 solution?
6
734
Solution Dilution calculation
735
How many mL of 95% alcohol are needed to prepare 100 mL of 70% alcohol?
73.7 mL
736
Which of the following pairs of fasting plasma glucose values demonstrates unequivocal hyperglycemia that can be used toward the diagnosis of diabetes mellitus? A. 160 mg/dL on two separate occasions B. 100 mg/dL and 125 mg/dL C. 75 mg/dL on two separate occasions D. 93 mg/dL and 195 mg/dL
A. 160 mg/dL on two separate occasions
737
Which photometric method is used primarily to measure antibody-antigen reactions? A. Chemiluminescence B. Turbidimetry C. Nephelometry D. Flow cytometry
C. Nephelometry
738
Regarding serum protein electrophoresis, which condition is associated with a beta-gamma bridge pattern? A. Liver cirrhosis B. Nephrotic syndrome C. Acute inflammation D. Monoclonal gammopathy
A. Liver cirrhosis
739
Which serum enzyme is elevated in all hepatobiliary disorders? A. Gamma-glutamyl transferase B. AST C. Creatinine kinase D. Amylase
A. Gamma-glutamyl transferase
740
The Friedewald formula can be used to indirectly determine the concentration of which of the following analytes? A. Triglycerides B. Phospholipids C. LDL cholesterol D. Lipase
C. LDL cholesterol
741
Which set of laboratory values corresponds to secondary hypothyroidism? A. Increased TSH, decreased free T4, decreased free T3 B. Decreased TSH, decreased free T4, decreased free T3 C. Increased TSH, normal free T4, increased free T3 D. Decreased TSH, increased free T4, increased free T3
B. Decreased TSH, decreased free T4, decreased free T3
742
For which of the following clinical chemistry analytes is it important to avoid hemolysis? A. Potassium B. Bilirubin C. AST D. All of the above are susceptible to hemolysis
D. All of the above are susceptible to hemolysis
743
Aldosterone regulates the levels of which of the following electrolytes? A. Sodium B. Magnesium C. Calcium D. Bicarbonate
A. Sodium
744
Laboratory findings for which of the following endocrine disorders include decreased morning plasma and/or salivary cortisol, decreased ACTH, and decreased sodium? A. Cushing disease B. Diabetes insipidus C. Addison disease D. Acromegaly
C. Addison disease
745
A specimen for blood gas analysis that is left at room temperature for more than 30 minutes would be expected to show which set of changes? A. Decreased PCO2, increased pH, increased PO2 B. Increased PCO2, decreased pH, decreased PO2 C. Decreased PCO2, decreased pH, decreased PO2 D. Increased PCO2, increased pH, increased PO2
B. Increased PCO2, decreased pH, decreased PO2
746
Acid Base Balance: Mnemonic (ROME)
747
Respiratory Acidosis
748
Respiratory Alkalosis
749
Metabolic Acidosis
750
Metabolic Alkalosis

AMT MT Exam (12 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions