Common Lab Tests

Question 1

Arterial Blood Gas (ABG)

Answer 1

These gases are collected to evaluate acid-base status (pH), ventilation (PaCO2), and oxygenation of arterial blood (PaO2)

Question 2

What 2 values are able to provide information on how well lungs are functioning to oxygenate blood?

Answer 2

Partial pressure of oxygen in arterial blood (PaO2) and % oxygen saturation of hemoglobin (SaO2)

Question 3

What information does partial pressure of carbon dioxide in arterial blood (PaCO2) provide?

Answer 3

Information on how well the lungs are able to remove carbon dioxide, changes in PaCO2 can directly affect balance of pH in body

Question 4

Bicarbonate (HCO3-)

Answer 4

An important component of the chemical buffering system that keeps blood from becoming too acidic or too basic and is often part of ABG test

Question 5

pH

Answer 5

7.4 (7.35-7.45)

Question 6

PaCO2

Answer 6

40 mmHg at sea level breathing ambient air (35-45mmHg)

Question 7

PaO2

Answer 7

97 mmHg at sea level breathing ambient air (80-100mmHg)

Question 8

HCO3-

Answer 8

24 mEq/L (22-26mEq/L)

Question 9

SaO2

Answer 9

95-98%

Question 10

Order of ABG results

Answer 10

pH->PaCO2->PaO2->HCO3-

Question 11

Acidemia

Answer 11

elevated acidity of blood pH, <7.35

Question 12

Alkalemia

Answer 12

decreased acidity of blood pH, >7.45

Question 13

Eucapnia

Answer 13

normal level of CO2 in arterial blood, PaCO2 35-45mmHg

Question 14

Hypercapnia

Answer 14

elevated level of CO2 in arterial blood, PaCO2 >45mmHg

Question 15

Hypocapnia

Answer 15

low level of CO2 in arterial blood, PaCO2 <35mmHg

Question 16

Hypoxemia

Answer 16

low level of O2 in arterial blood, PaO2 <80mmHg

Question 17

Mild hypoxemia

Answer 17

PaO2 60-79mmHg

Question 18

Moderate hypoxemia

Answer 18

PaO2 40-59mmHg

Question 19

Severe hypoxemia

Answer 19

PaO2 <40mmHg

Question 20

Hypoxia

Answer 20

low level of O2 in tissue despite adequate perfusion of the tissue

Question 21

Cardiac Biomarkers

Answer 21

Certain enzymes leak out of the heart cells and into blood after MI, cardiac enzyme studies measure levels of creatine phosphokinase (CK) and protein troponin in blood

Question 22

CK-MB

Answer 22

Relatively specific test for MI, it appears in blood ~4 hrs after infarction, peaks at 12-24 hrs and declines over 48-72 hrs

Question 23

Cardiac troponin-I

Answer 23

Specific marker for infarction and unlike CK-MB levels, it remains elevated for 5-7 days

Question 24

Cholesterol test

Answer 24

Aka lipid panel or lipid profile, measures the amount of cholesterol and triglycerides in the blood in order to determine the risk of atheroscelrosis

Question 25

What 4 types of lipids are measured during a cholesterol test?

Answer 25

Total cholesterol High-density lipoprotein (HDL) cholesterol Low-denisty lipoprotein (LDL) cholesterol Trigylcerides

Question 26

Which is considered good cholesterol?

Answer 26

HDL because it helps carry away LDL and is protective against atherogenesis

Question 27

Which is referred to as bad cholesterol?

Answer 27

LDL since it is associated with buildup of fatty plaques within the arteries which reduces blood flow

Question 28

Where are triglycerides stored?

Answer 28

Adipose tissue

Question 29

Complete blood cell count (CBC)

Answer 29

Measures red blood cell count, total white blood cell cunt, white blood cell differential, platelets, hemoglobin, and hematocrit

Question 30

Hematocrit (HCT)

Answer 30

Percentage of red blood cells in total blood volume

Question 31

What can a low hematocrit indicate?

Answer 31

Anemia, blood loss, and vitamin or mineral deficiencies

Question 32

What can a high hematocrit indicate?

Answer 32

Dehydration or polycythemia vera, a condition that causes an overproduction of red blood cells

Question 33

Partial Thromboplastin Time (PTT) & Prothrombin Time (PT)

Answer 33

Measure how quickly the blood clots, commonly used to monitor oral anticoagulant therapy or to screen for selected bleeding disorders