intro to respiratory system

Upper respiratory tract parts

Nasal cavity Oral cavity Pharynx Larynx

Lower respiratory tract

Trachea

1/2/3rd bronchus

bronchiole

terminal bronchiole

respiratory bronchiole

alveolar duct → sac → alveoli

Different parts of the Pharynx

Nasopharynx (behind nose)

Oropharynx (behind mouth)

Laryngopharynx

Which structure in Lower Respiratory Tract are inside lung?

2nd bronchus and below

Functions of Respiratory Tract

Ventilation

Waste elimination

filtration of foreign particles from air

humidity control

temp control

Upper respiratory system function

Olfaction

Draining sinuses

Producing and resonance of speech

Larynx

Voice box

Pharynx function

dual passage way for esophagus and trachea

Trachea

Supported by C shaped hyaline cartilages rings

prevents collapse

posterior/back side open for esophagus

trachealis muscle closes posterior gap

Whats the trachealis muscle innervated by in trachea?

GVE (visceral efferent, autonomic)

Carina

The split where trachea divides

(left and right rbonchus)

Around sternal angle landmark

Sternal Angle / Angle of Louis

place where top of sternum meets body

Right vs Left Primary Bronchus

Right

Wider

Shorter

More vertical

Left

Narrower

Longer

More horizontal

Clinical Correlate for left / right bronchus

a foreign object would enter the right bronchus due to it being WIDER and VERTICAL

Right vs Left lung lobes

Left

2 lobes (Superior, Inferior)

has 2 due to space of heart

Right

3 lobes (Superior Middle Inferior)

Hilum

doorway of the lung

depression where blood vessels, nerves, and ducts leave an organ

Pulmonary circulation

Right ventricle → pulmonary arteries (deoxy blood) → lungs → pulmonary veins (oxy blood) → left atrium

Which structures enter/leave lymph node?

• Bronchi

• Pulmonary arteries

• Pulmonary veins

• Lymphatics

  • Nerves

Pulmonary Pleurals

Parietal Pleura (covers chest wall)

Visceral Plerua (covers lung surface)

Whats between pulmonary pleuras?

• Pleural fluid to reduce friction

Pleural cavity

Very thin

nearly No Space

has some serous fluid

Clinical Correlate: Pleurisy/Pleuritis

Inflammation of pleura

• Pain with breathing

• Increased friction

Clinical Correlate: Pleural Plaques

thickening of pleura that attaches to ribs

happens due to asbestos exposure

Clinical Correlate: Mesothelioma

cancer of the serous tissues that lines body cavities

abestos exposure

Systemic circulation

arteries(oxy blood)→system organs →Veins (deoxy blood)

Inspiration AND its main muscle

Diaphragm

Diaphragm contracts → Moves downward → Thoracic volume increases → Air enters lungs

Expiration and muscle

Diaphragm relaxes -> Thoracic volume decreases -> Air exits lungs

Quiet breathing main muscle

Diaphragm AND intercostal muscles for inspiration

elastic recoil of alveoli for expiration

Forced breathing main muscle

Neck muscles

SCM
Scalenes

Intercostals

Serratus muscles

Pectoralis muscles

Abdominal muscles

Diaphragm innervation

C3, C4, C5

"C3, 4, 5 keep the diaphragm alive."

intercostal innervation

T1-T11d

Diaphragm muscle openings

Caval opening
Esophageal hiatus

Aortic hiatus

Caval opening part and innervation

Inferior vena cava

T8 vertebral

Esophageal hiatus part and innervation

esophagus + vagus nerve (T10)

Aortic hiatus part and innervation

descending aorta (T12)

3 layers of intercostal muscles from external to internal

external intercostal

internal intercostal

innermost intercostal

COPD

caused by smoking usually

Damaged alveoli

• Difficult expiration

• Air trapping

• Barrel chest

• Accessory muscles used even at rest