Gross Anatomy of Lungs and Pleura

Question 0

What do the parietal/visceral pleura have to do with microscope slides?

Answer 0

Like a glass slide with some liquid underneath it, the pleural layers are “glued” together with serous secretions.

Question 1

What germ layer do the lungs come from?

Answer 1

Endoderm - they’re an outpouching of the gut tube.

Question 2

4-5 things that each lung root (hilum) contains?

Answer 2

Main bronchus.
Blood vessels (arteries and veins).
Lymphatics.
Nerves.

Question 3

What movements increase the volume of the thoracic cavity? (other than the motion of the diaphragm?)

Answer 3

The “bucket handle” motion of the ribs and the “pump handle” motion of sternum increase the transverse and anteroposterior diameters.

Question 4

Muscles used in normal inspiration?

Extra muscles used when needed?

Answer 4

Normal: Diaphragm, external intercostals, anterior fibers of internal intercostals.
Extra: anything attached to rib cage.

Question 5

Muscles normally used in expiration?

Extras?

Answer 5

Normally: Passive recoil.
Extra: Internal intercostals, abdominal muscles.

Question 6

What spinal roots do the phrenic nerves come from?

Answer 6

C3, C4, C5 (keep the diaphragm alive)

Question 7

What happens to the diaphragm during inspiration if one phrenic nerve is lesioned?

Answer 7

The side of the diaphragm with the lesion will paradoxically elevate during inspiration (due to negative thoracic cavity pressure).

Question 8

What ribs does the costo-diaphragmatic recess span in the mid-clavicular line?

Answer 8

6th - 8th ribs

Question 9

What ribs does the costo-diaphragmatic recess span in the mid-axillary line?

Answer 9

8th - 10th rib.

Question 10

What ribs does the costo-diaphragmatic recess span in the paravertebral line?

Answer 10

10th - 12th ribs.

Question 11

Which lung has more lobes?

Answer 11

Right lung - it has 3.

Question 12

Which lobe of the lung is most anterior?

Answer 12

The superior lobe (for both lungs).

Question 13

Surface landmark for where the trachea bifurcates?

Answer 13

Sternal angle.

Question 14

Mnemonic for how the pulmonary artery relates to spatially to the bronchi in each hilum?

Answer 14

RALS - Right anterior, left superior.
Right: pulmonary a. is anterior to bronchus.
Left: pulmonar a. is superior to bronchus.

Question 15

When looking at chest x-rays, you need 2 views.

Answer 15

Right.

Question 16

If Mitch Lewis accidentally inhales a painkiller pill for his kidney stone pain, which bronchus is it more likely to end up in?

Answer 16

The right bronchus -it’s wider and more vertical.

Question 17

What’s the carina?

Answer 17

U-shaped cartilage in the trachea just before the bifurcation.

Question 18

What defines a bronchopulmonary segment?

Answer 18

Lung tissue that shares a tertiary bronchus and branch of a pulmonary artery.
A segment can be independently surgically resected.

Question 19

How many bronchopulmonary segments does each lung have?

Answer 19

The right definitely has 10.

The left… might have 8, might have 10.

Question 20

Where do the lymphatics of each lung drain?

Answer 20

Right lung -> right lymphatic duct (drains into R. subclavian v.)
Left superior lobe -> thoracic duct (drains into L. subclavian v./L. jugular v. junction).
Left inferior lobe -> right lymphatic duct.

Notably, the left inferior lobe drains to the opposite side.

Question 21

What landmark will tell you if a cross-sectional image is in the superior vs. inferior mediastinum?

Answer 21

The trachea - only in the superior mediastinum.

Question 22

If you can see the trachea, which lobes of the lungs can you usually see?

Answer 22

Just the superior lobes - for most of it.

Question 23

What separates the L. superior lobe from the L. inferior lobe?

Answer 23

The oblique (major) fissure.

Question 24

What separates the R. upper lobe from the middle lobe?

Answer 24

The horizontal (minor) fissure.