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RespiRatoRy ` RESPIRATORY—ANATOmY RespiRatoRy ` RESPIRATORY—ANATOmY seCtioN iii 663

Lung anatomy Right lung has 3 lobes; Left has Less Lobes (2) and Lingula (homolog of right middle lobe). Instead
of a middle lobe, left lung has a space occupied by the heart A .
Trachea Upper lobe
Relation of the pulmonary artery to the bronchus at each lung hilum is described by RALS—Right
Anterior; Left Superior. Carina is posterior to ascending aorta and anteromedial to descending
Horizontal
aorta B . fissure Oblique fissure
Right lung is a more common site for inhaled foreign bodies because right main stem bronchus is
wider, more vertical, and shorter than the left. If you aspirate a peanut:
Middle lobe
Lingula
Carina ƒ While supine—usually enters superior segment of right lower lobe.
Lower
ƒ While lying on right side—usually enters right upper lobe. Lower
lobe
lobe
Inferior lobe
ƒ While upright—usually enters right lower lobe.
Right Left R L L R
bronchus bronchus Anterior view Posterior view
Anterior view Posterior view
Clavicle Midclavicular line
C7
1 T1
2
RUL 1 LUL 3 RUL
ICS1 Needle position 4
Horizontal fissure 2 for tension pneumothorax Oblique 5 T5 Horizontal
ICS2 LUL fissure fissure
3 6
RML RML
ICS3
4 LLL 7
Oblique fissure
Oblique fissure ICS4 8 T8 Oblique fissure
5
RLL ICS5 LLL 9 T9 RLL
6
10
7 11
Pleura Lingula 8 T12
9 12
10 L1
ICS = intercostal space
11
A B
RUL LUL
AAo
SVC PA
DAo
Carina
RML
RLL LLL

Diaphragm structures Structures perforating diaphragm: Number of letters = T level:
Inferior vena Central tendon ƒ At T8: IVC, right phrenic nerve T8: vena cava (IVC)
cava (T8) Esophagus ƒ At T10: esophagus, vagus (CN 10; 2 trunks) T10: (O)esophagus
(T10)
ƒ At T12: aorta (red), thoracic duct (white), T12: aortic hiatus
azygos vein (blue) (“At T-1-2 it’s the red, I ate (8) ten eggs at twelve.
white, and blue”)
Diaphragm is innervated by C3, 4, and 5 C3, 4, 5 keeps the diaphragm alive.
Rib (phrenic nerve). Pain from diaphragm Other bifurcations:
Aorta ƒ The common carotid bifourcates at C4.
(T12) irritation (eg, air, blood, or pus in peritoneal
Vertebra cavity) can be referred to shoulder (C5) and ƒ The trachea bifourcates at T4.
Inferior view ƒ The abdominal aorta bifourcates at L4.
trapezius ridge (C3, 4).

FAS1_2019_16-Respiratory.indd 663 11/8/19 7:34 AM