Chapter 1: The Anatomy and Physiology of the Respiratory System

What is the Upper Airway composed of?

Upper airway:

Nose, oral cavity, pharynx, and larynx

What is the purpose of the Upper Airway?

Upper airway purpose:

1) CONDUCTING air

2) HUMIDIFYING inspired air

3) PREVENTING foreign materials from entering the lower airways

4) SPEECH

5) SMELL

What makes up the lower airway?

Lower airway:

Everything else

-(Below the trachea)

↪trachea, bronchi, bronchioles, alveoli

What is the nose composed of?

Nose is composed of:

-Bones

-cartilage

-hard palate

-soft palate

-conchae

-sinuses

What can sinuses cause?

Sinuses can make it so that certain treatments can't get done (patient can't breathe through their nose, etc)

What is the purpose of conchae?

Conchae INCREASE the SURFACE AREA

↪ Turbulence makes it so that heat/moisture can be picked up and HUMIDIFIED

What is the oral cavity composed of?

Oral cavity is composed of:

-Tongue

-vestibule

-hard and soft palates

-uvula

-stratified squamous epithelium

-palatine arches

Where is vestibule located?

Vestibule is located BETWEEN the teeth and lips

What do high levels of epithelium in a sputum sample suggest?

HIGH levels of epithelium in a sputum sample suggests a BAD sample, it didn't actually come from the lungs

What are the palatine arches?

Palatine arches:

2 folds of MUCOUS MEMBRANE along the LATERAL borders of the POSTERIOR oral cavity

What is the pharynx composed of?

Pharynx is composed of:

-Nasopharynx

-Oropharynx (soft palate → tongue base)

-Laryngopharynx

What is the nasopharynx also known as?

Nasopharynx is also known as:

Adenoids/pharyngeal tonsils

What kind of epithelium does the nasopharynx have?

Nasopharynx epithelium:

pseudostratified ciliated columnar

What makes up the oropharynx?

Oropharynx is made up of:

Lingual and palatine tonsils

What kind of epithelium does the oropharynx have?

Oropharynx epithelium:

stratified squamous epithelium

Where is the laryngopharynx located?

Laryngopharynx is located:

POSTERIOR to the epiglottis

- Pharyngeal reflex

What kind of epithelium does the laryngopharynx have?

Laryngopharynx epithelium:

Noncilitated stratified squamous epithelium

What are the functions of the larynx?

Larynx functions:

① PASSAGEWAY

② SPEECH

③ PROTECTION

↪The epiglottis on top of the voice box acts as a lid to PREVENT food from entering the lungs

What are the 9 cartilages that the larynx is made up of?

Larynx cartilage:

-*THYROID

-*CRICOID

-arytenoid (2)

-corniculate (2)

-cuneiform (2)

-*EPIGLOTTIS

What is the most important cartilage of the larynx?

The most important cartilage of the larynx is:

→CRICOID because it can help bring airway into view (with cricoid pressure)

What else is the larynx composed of?

The larynx is also composed of:

-false vocal cords

-true vocal cords

-glottis

-muscles

What is the lower airway known as?

The lower airway is also known as:

→ tracheobronchial tree

What is the cartilaginous airway?

Cartilaginous airway:

The environment ➜ TERMINAL BRONCHIOLES

What is the noncartilaginous airway?

Noncartilaginous airway:

Respiratory bronchioles ➜ ALVEOLI

-Also known as the Respiratory Zone

➔ Gas exchange occurs here

What are most parts of the lower airway?

Most parts of the lower airway are CARTILAGINOUS AIRWAY, and the very smallest part of the lower airway is the non-cartilaginous airway

How does air move from the environment?

Air from the environment first enters your body and travels through cartilaginous airways, moving into smaller tubes called terminal bronchioles, and reaches the alveoli where oxygen goes into the blood and carbon dioxide comes out

What are the three layers of the lower airway?

Lower airway layers:

① EPITHELIAL LINING

② LAMINA PROPRIA

③ CARTILAGE

What is the epithelial lining made up of?

Epithelial lining:

-Pseudostratified ciliated columnar:

↪ Where cilia DISAPPEAR in the TERMINAL BRONCHIOLES

-Mucous blanket:

-95% water

↪ Gel layer

↪ Sol layer

↪ Mucociliary escalator

-Goblet cells

What is the gel layer?

Gel layer:

The top layer and is more viscous

What is the sol layer?

Sol layer:

The bottom layer of the mucous blanket that is WATERY

-Cilia are located here

Where is the mucociliary escalator located?

The mucociliary escalator is located in the EPITHELIAL lining

What do goblet cells do?

Goblet cells secrete MUCOUS (Certain things can trigger your mucous to be active)

What is the lamina propria?

Lamina Propria:

LOOSE, fibrous CONNECTIVE TISSUE

-(where blood vessels and lymphatic vessels are found)

↪ Blood vessels/lymphatic vessels

↪ Submucosal/bronchial glands

↪ Smooth muscle

↪ Nerve branches

↪ Cartilage

What does the lamina propria contain?

Lamina propria contains:

Submucosal/bronchial glands, smooth muscle, nerve branches, cartilage

What does cartilage act as?

Cartilage acts as a PROTECTIVE layer

What is the immune response for the lower airways?

Lower airway immune response:

IgE Antigen-Antibody Reaction

What is the IgE Antigen-Antibody reaction (IgE receptors/mast cell)?

IgE Antigen-Antibody reaction:

The mast cell breaks down

-INCREASING vascular permeability and mucous production

↪causing EDEMA and smooth muscle CONTRACTION

What is the cartilagenous airway made up of?

Cartilagenous airway:

-Trachea

-mainstem bronchi

-lobar bronchi

-segmental bronchi

-subsegmental bronchi

*Trachea ➔ Subsegmental bronchi = cartilagenous airway

How long and wide is the trachea?

The trachea is :

-11-13 cm long

=1.5-2.5 cm in diameter

How many C-shaped rings of cartilage does the trachea have?

The trachea has:

15-20 C-shaped rings of cartilage

What is the Carina?

Carina:

The carina is where the trachea BIFURCATES (important landmark)

↪ The landmark to stop the tube from going too far in the throat

-will naturally go RIGHT, which results in only ventilating one lung= bad

What are the differences between the right and left mainstem bronchi?

Right: 25 degree angle, shorter, and wider

Left: 40-60 degree angle, and narrower

*Basically, the right mainstem bronchi is easier for things to go into (ex: someone aspirates)

If you're trying to push a tube into someones lung, which direction will it go in?

It will always go to the right since it is wider than the left

What is the diameter of the subsegmental bronchi?

Subsegmenetal bronchi:

1-4 mm diameter (very small and can be blocked off easily)

What is the subsegmental bronchi surrounded by?

The subsegmental bronchi is surrounded by CONNECTIVE TISSUE (blood vessels, nerves, lymphatic vessels)

What makes up the noncartilagenous airways?

Noncartilagenous airways:

Bronchioles and Terminal bronchioles

What is the diameter of bronchioles?

Bronchioles diameter:

LESS than 1 mm diameter (no cartilage)

What generations do the bronchioles make up?

Bronchioles generations:

10-15

What is the diameter of the terminal bronchioles?

Terminal bronchioles diameter:

→ LESS than .5

What generations do the terminal bronchioles make up?

Terminal bronchiole generations:

→ 16-19

Where does cilia and mucous glands disappear?

Cilia and mucous glands disappear:

At the TERMINAL bronchioles (Gen. 16-19)

What do the terminal bronchioles contain?

The terminal bronchioles contain:

Canals of Lambert, Clara cells, and the respiratory zone

What does the Canals of Lambert provide?

Canals of Lambert:

May provide ventilation

What do Clara cells do?

Clara cells:

May have a SECRETORY function

Where is the respiratory zone located?

Respiratory zone:

DISTAL to terminal bronchioles

What is the bronchial blood supply composed of?

Bronchial blood supply is composed of:

Arterial and venous blood

What are the bronchial arteries?

Bronchial arteries supply OXYGENATED blood to the tracheobronchial tree up to the terminal bronchioles

What are the pulmonary arteries?

The pulmonary arteries carry DEOXYGENATED blood to the lungs

➔ Carries the deoxygenated blood from the heart to the lungs to then get oxygenated

What does the arterial blood supply contain?

Arterial blood supply contains:

→ Bronchial arteries and pulmonary arteries (unoxygenated blood; takes blood away from the heart to the lungs to get oxygenated)

What does the venous blood supply contain?

Venous blood supply contains:

Venous admixture (point where venous and arterial blood mix)

↪ A mix of oxygenated and deoxygenated blood

What are the sites of gas exchange?

Sites of gas exchange:

-Respiratory bronchioles

-alveolar ducts

-alveolar sacs

-A/C membrane

-primary lobule

What is the A/C membrane?

A/C membrane:

Between the capillaries and the alveoli

-The O2 from the lungs diffuses into the capillaries

Where does the majority of gas exchange occur?

The majority of gas exchange occurs at the A/C MEMBRANE

↪ Alevolar-Capillary membrane

What are the alveolar cells in the alveolar epithelium?

Alveolar cells:

-Type I

-Type II

↪ Produces SURFACTANT

-Type III

-Pores of Kohn

↪ Connects adjacent alveoli, allowing air to flow and move between them

*Interstitium

What is the interstitium?

Interstitium:

CONNECTIVE TISSUE!!!!

-Supports clusters of alveoli (supports alveoli and connective tissue; can have an effect on gas exchange)

*The interstitium is what holds the alveoli and capillaries close together, which allows for efficient gas exchange

➔ If the interstitium is damaged, then there will be inefficient gas flow

What is the pulmonary vascular system composed of?

Pulmonary vascular system is composed of:

Arterioles, capillaries, venules, and veins

How many pulmonary arteries are in the pulmonary vascular system?

Pulmonary arteries:

2, one for each lung

How many veins are there in the pulmonary vascular system?

Veins in the pulmonary vascular system:

4 pulmonary veins

-thinner walls increase the vein capacitance

What do the arteries do?

Arteries:

Carry DEOXYGENATED blood AWAY from the heart TO the lungs

What are arterioles?

Arterioles:

RESISTANCE vessels

What do the capillaries do?

Capillaries:

Carries blood past the A/C MEMBRANE

What do the venules do?

Venules:

Allow blood to come out

Where is the pulmonary lymphatic system located?

Pulmonary lymphatic system:

Just below the visceral pleura

What is the function of the pulmonary lymphatic system?

Pulmonary lymphatic system function:

REMOVES excess fluid and protein molecules that LEAK from capillaries

-Large one-way valves that send fluid toward the hilum; surrounded by smooth muscle

↪More lymphatic vessels in the Left lung

What do lymphatic vessels do?

Lymphatic vessels:

They are large, one-way valves that send fluid toward the hilum and are surrounded by smooth muscle

Where are there more lymphatic vessels at?

There are more lymphatic vessels in the left lung

Where are there no lymph vessels?

There are NO lymph vessels in the alveolar wall

What happens during SNS?

During Sympathetic:

-INCREASED heart rate and contraction strength

-RELAXES Bronchial smooth muscle

↪Allows dilation of airways to get more air in/out

-DECREASE secretions in Bronchial glands and salivary glands

-DECREASE GI system motility (not hungry, saves energy)

-WIDENS pupils

*Wants to get as much O2 pumped as possible, so by relaxing the smooth muscle and decreasing secretions, allows the flow to be efficient

What happens during PSNS?

During Parasympathetic:

-DECREASED heart rate and contraction strength

-CONSTRICTS Bronchial smooth muscle

-INCREASE secretions in Bronchial glands and salivary glands

-INCREASE GI system motility

-CONSTRICTS pupils

How does the bronchial smooth muscle react in the SNS?

Bronchial smooth muscle SNS:

RELAXES (Relaxes so that the lungs can take in as much air as possible)

How does the bronchial smooth muscle react in the PSNS?

Bronchial smooth muscle PSNS:

CONSTRICTS

How do bronchial glands react in the SNS?

Bronchial glands SNS:

DECREASE secretions (Decreases secretions to keep the airways open and efficient)

How do bronchial glands react in the PSNS?

Bronchial glands PSNS:

INCREASES secretions (to protect and maintain the airways)

What are the lungs made up of?

Lungs are made up of:

Apex, base, hilum, fissures, lobes, and segments

Where is the apex located?

Apex:

1st rib

-upper portion of the lungs

Where is the base located?

Base:

6th rib anteriorly, 11th rib posteriorly

-Lower portion of the lungs

What occurs at the hilum of the lungs?

Hilum:

The pulmonary artery, pulmonary vein, bronchi, and lymphatic vessels ENTER and EXIT here

What are the number of lobes on the left and right lung?

Left lung:

-2 lobes

↪ The heart is in the way

Right lung:

-3 lobes

What are the number of fissures on the left and right lung?

Left lung:

-1 fissure

Right lung:

-2 fissures

What do the lobes break down into?

Lobes break down into segments, which are important for draining secretions

What are the pulmonary structures?

Pulmonary structures:

Mediastinum and pleural membranes

What are the three parts of the pleural membranes

Pleural membrane components:

① Visceral

② pleural space/cavity

③ pleural

Why does a pleural effusion need to be drained?

Pleural effusion:

There is EXCESS fluid in the pleural space

-Not in the lungs, so can't just be coughed out

What are the bones of the thorax?

Thorax bones:

Thoracic vertebrae, ribs, and sternum

What is the diaphragm important for?

The diaphragm is important for:

Inhalation and exhalation

-The hemidiaphragms come together to form the central tendon

What is the diaphragm innervated by?

Diaphragm is innervated by the:

Phrenic nerve (Injury to the phrenic nerve= can't use diaphragm)

What are the accessory muscles of inspiration?

Accessory muscles of inspiration:

-Pectoralis major

-Trapezius

-Scalene

-Sternocleidomastoids

-External intercostals

What are the accessory muscles of exhalation?

Accessory muscles of exhalation:

-Rectus abdominus

-External obliques

-Internal obliques,

-Transverse intercostals

-INTERNAL INTERCOSTALS

(Mostly abdominal muscles)