Wk 1 - Respiratory Anatomy, breathing mechanics

What is the conducting zone?

Transport of air into lungs

Name the structures where air travels through.

Nose → Pharynx → Larynx → Trachea → Bronchus → Bronchiole

Which side of the lungs has 3 lobes?

Right side

Which side of lungs has 2 lobes and why?

Left side due to less space due to heart, space in the left side is limited.

What happens in the respiratory zone?

Gas exchange occurs

What structures are in the respiratory zone?

Bronchioles → Alveolar Duct → Alveoli → Alveolar Sacs

What part of the trachea is made out of hyaline cartilage?

• Thyroid

• Arythenoid

• Cricoid Cartilage

What is the function of the c-shape ring?

Provides structure and reinforcement which allows the trachea to remain patent during pressure changes.

What is the fx of the epiglottis?

It closes over the trachea when swallowing to prevent aspiration

Landmark for Hyoid Bone, which vertebrae level?

C4

Landmark for Cricoid, which vertebrae level?

C6

Landmark for carina, which vertebrae level?

T4

What does the primary bronchi enter into the lung via what?

Hilum

What is the significant with the right bronchi?

Right is SHORTER, WIDER, and MORE VERTICAL

How many lobes does the lung have and what are the significance between the two sides?

• 3 on the right, horizontal fissure

• 2 on the left, lingula and cardiac notch

• BOTH has the oblique fissure

Size < 1 mm is referred to as ___________ .

Bronchiole

Alveolar ducts are made of what type of tissue?

• Smooth Muscles

• Elastic Fibers

• Collagen Fibers

Branches off terminal bronchioles, what is the order?

→ Respiratory Bronchiole → Alveolar Duct → Alveoli

How many alveoli are in the lungs?

~ 300 million

What type of cells are the aveoli made of?

• Type 1 & 2 cells

What is the purpose of Type 1 Cells and what type of cell?

Simple Squamous Cells → Gas Exchange

What is the purpose of Type 2 Cells and what type of cell?

Cuboid Cells → Prod. Surfactant and is scattered throughout.

What is the alveoli-capillary membrane?

Alveoli & Capillaries + Basal Lamina = Respiratory membrane

How does gas exchange occur?

Via simple diffusion across the respiratory membrane

What is the purpose to the surfactant?

To coat the gas when it’s exposed to the alveolar surface.

What is the AKA for alveolar macrophages?

DUST Cells

What is the purpose of alveolar macrophages (dust cells)?

Detecting and neutralizing foreign material

• Bacteria

• Viruses

• Pollutants

How are the dead macrophages removed?

From respiratory zone → Pharynx

• Clear and swallow ~ 2 million macrophages/hr

What are the two phases of breathing?

1. Inspiration

2. Expiration

What happens during breathing?

Volume changes → Pressure changes → Flow of gases to equalize pressure

What is the atmospheric pressure?

Pressure that is produced by the air surround our body

How much mmHg and psi equal to 1 atmosphere?

• 760 mmHg

• 14.7 psi

What is intrapulmonary pressure?

Pressure within the alveoli

What is the mechanism of breathing during intrapulmonary pressue?

It rises and falls with the phases of breathing and its always trying to match the atmospheric pressure.

How much difference in mmHg is in intrapleural pressure than intrapulmonary pressure?

~ 4 mmHg

What happens during inspiration?

Inspiratory muscle CONTRACTS →

Thoracic cavity size INCREASE →

Volume INCREASES →

Pressure DECREASES

= Partial VACUUM effect → More AIR in LUNGS

*KEEPS move UNTIL pressure = atmospheric pressure

What happens during expiration?

Inspiratory muscles RELAXES →

Thoracic cavity DECREASES →

Volume DECREASES →

Pressure INCREASES

= Gases in lung are FORCED OUT →

UNTIL Intrapulmonary pressure = atmospheric pressure

What is the AKA for lung collapse?

Atelectasis (AT-E-LEC-TA-SIS)

What is atelectasis?

When there is a EQUALIZED intrapleural and intrapulmonary pressure

Pneumothorax

Air in pleural space

Hemothorax

Blood in pleural space

Pyothorax

Purulent exudate in pleural space

Chylothorax

Lymph in pleural space

Boyle’s Law

As volume increase, gas pressure decreases

As volume decreases, gas pressure increases

Dalton’s Law