Lecture 4 - Physiologic Basics of The Lung Exam

Question 1

back of the nose and throat

Answer 1

• nasal cavity and the pharynx (nasopharynx)

Question 2

cartilaginous structure containing vocal folds

Answer 2

larynx

Question 3

midline, non-paired conducting air-way

Answer 3

trachea

Question 4

branching airways containing variable amounts of cartilage

Answer 4

Bronchi

Question 5

3 lobes?

Answer 5

right lung

Question 6

2 lobes with cardiac notch?

Answer 6

Left lung

Question 7

branching airway lacking cartilage surrounded by smooth muscle

Answer 7

Bronchioles

Question 8

delicate, balloon like structures where gas exchange occurs

Answer 8

Alveoli

Question 9

Ventilation:

Answer 9

• the conducting zone
• skeletal muscle changes V of thoracic cavity -> pressure change -> air moves
• conducting airways: nasopharynx -> terminal bronchiole
• air moves in due to pressure gradient

Question 10

Diffusion:

Answer 10

• respiratory/exchange zone
• Driven by concentration gradient
• extreme SA vasculature over the alveoli
• respiratory bronchiole -> alveoli

Question 11

What is the V after a quiet inspiration?

Answer 11

3L

Question 12

What are the components of the Ventilatory apparatus?

Answer 12

• lungs
• chest wall
• muscles

Question 13

What muscles are active during inspiration?

Answer 13

• external intercostals - move ribs up ad out
• diaphragm - contracts and decends

V of thoracic cavity increases -> decreasing intrathoracic pressure -> decreasing pressure in lungs -> movement of air into lungs

Question 14

What muscles become active during forced inspiration?

Answer 14

scalenes and SCM

Question 15

What muscles are involved in expiration?

Answer 15

diaphragm - relaxes and rises
external intercostals - relax, moving ribs down and in

V thoracic cavity decreases -> increasing intrathoracic pressure -> increasing airspace lung pressure -> movement of air out

Question 16

What pleura lines the lungs?

Answer 16

visceral pleura

Question 17

Which pleura lines the chest wall?

Answer 17

parietal pleura

Question 18

The space between visceral and parietal pleura?

Answer 18

pleural cavity/intrapleural space

Question 19

Features of the pleural cavity:

Answer 19

• contains small amount of water - ‘connects’ chest wall to alveoli
• movement of thoracic cage and diapgragm -> change in pleural cavity pressure (slightly more negative) -> change in alveolar pressure
• alevoli expand as lungs expand
• intrapleural pressure is always lower than alveoli

Question 20

What is the role of the nasal cavity?

Answer 20

warming and moistening air

Question 21

what is the role of the Larynx?

Answer 21

phonation (speaking) and protection of airways from fluid/food

Question 22

Key aspects to Pleural Effusion (unilateral):

Answer 22

• fluid in pleural cavity causing too much pressure - difficult for airpaces to expand
• lungs are dull to percusion
• difficult to hear breathing
• causes: cancer, infection, trauma

Question 23

Key aspects to Pleural Effusion (bilateral):

Answer 23

• fluid in pleural cavity causing too much pressure - difficult for airpaces to expand
• lungs are dull to percusion
• difficult to hear breathing
• causes: something systemic, congestion due to heart failure, bilateral infection, inflammation

Question 24

What is Consolidation?

Answer 24

“gunk” in the airways and alveoli
coarse crackles -> fluid in larger airways
* both inspiration and expiration
fine crackels -> smaller airways
* both inspiration and expiration

Causes: infectious mostly
hear: coarse crackles, bronchophony, decreased breathe sounds, dull percussion

if it is higher up - as you ausciltate down find normal sounds

Question 25

Wheeze:

Answer 25

small airway is narrowed/constricted
high-pitched musical sound
common in: asthma, COPD, inflammation of bronchioles, pulmonary edema
inspiration normal
experation - hear it

Question 26

Stridor:

Answer 26

large airway narrowed/constricted
louder, harsher sound on inspiration (sometimes also expiration)
in upper airways (trachea and above)
causes: infection, trauma, aspiration