CH 6: Principles of Pathophysiology

Question 1

What are the chemical components of inhaled air?

Answer 1

79% nitrogen, 21% oxygen

Question 2

What is tidal volume?

Answer 2

The volume of air moved in one cycle of breathing.

Measured in mL.

Question 3

What is minute volume?

Answer 3

The amount of air breathed in during each respiration X number of breaths/minute.

Question 4

What is dead air space?

Answer 4

Air that occupies space between mouth and alveoli but that does not actually reach the area of gas exchange.

Question 5

What is the seat of respiratory control?

Answer 5

Medulla oblongata

Question 6

What can interfere with the medulla oblongata?

Answer 6

Stroke
Infection
Toxins / drugs
Brain trauma / intracranial pressure

Question 7

How is ventilation activated?

Answer 7

Changing pressures in the thorax.

Question 8

What is the chief culprit of lung tissue disruption?

Answer 8

Trauma

Can also be: medical problems (congestive heart failure, sepsis)

Question 9

What is the result of lung tissue disruption?

Answer 9

Low oxygen (hypoxia) and high carbon dioxide levels (hypercapnia)

Question 10

What are chemoreceptors?

Answer 10

Chemical sensors in the brain and blood vessels that identify changing levels of O2 and CO2

Question 11

What is the liquid portion of the blood?

Answer 11

Plasma

Question 12

How does blood transport oxygen?

Answer 12

By binding the oxygen to the hemoglobin in red blood cells.

ALSO

By dissolving in plasma (lesser extent)

Question 13

What is plasma oncotic pressure?

Answer 13

The pull exerted by large proteins in the plasma that tends to PULL water from the body INTO the bloodstream.

Question 14

What is hydrostatic pressure?

Answer 14

Pressure within a blood vessel that tends to PUSH water OUT of the vessel.

Question 15

The most common blood dysfunctions occur because of what?

Answer 15

Inadequate blood volume - BLEEDING/DEHYDRATION

Question 16

What are stretch receptors?

Answer 16

Sensors in blood vessels that identify internal pressure

Question 17

What role does the autonomic nervous system play in vessel diameter?

Answer 17

Sympathetic nervous system - fight/flight: constricts vessels
Parasympathetic nervous system - vessels relax

Question 18

What is stroke volume?

Answer 18

The amount of blood ejected from the heart in one contraction.

Question 19

What is preload?

Answer 19

The amount of blood returned to the heart prior to the contraction. Ie, how much it is filled.

Question 20

What is cardiac output?

Answer 20

The amount of blood ejected from the heart in 1 minute. (heart rate X stroke volume)

Question 21

What are the two types of heart dysfunctions?

Answer 21

Mechanical or electrical

Question 22

What is a V/Q match?

Answer 22

Ventilation/perfusion match.

The alveoli are supplied with enough air and the air is matched with sufficient blood in pulmonary capillaries to permit optimum exchange of O2 and CO2.

Question 23

How much of the body is made up of water?

Answer 23

60%

Question 24

Where in the body do you find water and in what proportions?

Answer 24

Intracellular - 70%
Intravascular - 5%
Interstitial - 25%

Question 25

What is edema?

Answer 25

Swelling associated with the movement of water.

Question 26

What is hypersensitivity?

Answer 26

An exaggerated response by the immune system to a particular substance.