Module A2: Upper Module A2: Upper Airway Anatomy & Airway Anatomy & PhysiologyPhysiology

ObjectivesObjectives

Classify epithelial tissue based on cell type and tissue layers.

Identify location of tissue epithelium in the respiratory system.

Describe the major structures and functions of the upper and lower airways.

Contrast and compare mouth and nose breathing. Explain how placing an endotracheal tube in the

airway will affect the humidification and filtering process.

The lung is for gas exchange.The lung is for gas exchange.

John B. West

Respiratory Physiology: The Essentials

Function of the Lungs/HeartFunction of the Lungs/Heart

Provide Ventilation Provide Respiration

Exchange of Carbon Dioxide and Oxygen Humidify and Protect Pump oxygen to vital organs

Cellular metabolism

Failure of the Lungs/HeartFailure of the Lungs/Heart

Hypoxemia – low oxygen level in the blood Decreased PaO2

Hypoxia - low oxygen level at the tissue level Decreased oxygen at the cellular level can

cause death of the tissue Presence of anaerobic respiration

VentilationVentilation

Brain Muscles Lungs

Inability of the lungs to remove carbon dioxide leads to hypercarbia, which is an elevated amount of carbon dioxide in the blood stream (PaCO2)

ARTIFICIAL AIRWAYSARTIFICIAL AIRWAYS

INTUBATION

ARTIFICIAL AIRWAYSARTIFICIAL AIRWAYS

INTUBATION

Tracheotomy with tracheostomy tube:1 - Vocal cords2 - Thyroid cartilage3 - Cricoid cartilage4 - Tracheal cartilages5 - Balloon cuff

Intubation – Insertion of an Endotracheal Tube

Extubation – Removal of the Endotracheal Tube

Anatomy of the Respiratory Anatomy of the Respiratory SystemSystem

Tissue Epithelium Upper Airway Lower Airway Site of Gas

Exchange Pulmonary Vascular

System

Neural Control Lungs Mediastinum Thorax Muscles of

Ventilation

Four Tissue TypesFour Tissue Types

Epithelial Tissue Connective Tissue

Bone, Cartilage, Blood, Fibrous Muscle Tissue Nervous Tissue

Neurons conduct electrical impulses

Epithelial TissueEpithelial Tissue

Epithelium Covers and protects the body surface Lines body cavities Forms many glands Specializes in moving substances into and

out of the blood

Epithelial Cell TypeEpithelial Cell Type

Squamous Cells Cuboidal Cells Columnar Cells

•Lots of Surface Area

•aka Pavement, Sunny-side up egg

•Great for Diffusion of Gases

•Lots of Volume

•Volume = Cytoplasm

•Cytoplasm means metabolism

•Less diffusion

•Height is 2x Width

•Usually associated with secretion or absorption of material

•Very little diffusion

HISTOLOGY 101HISTOLOGY 101

Classification of Epithelium Classification of Epithelium by Layersby Layers

Simple Epithelium – Single Layer Simple squamous Simple cuboidal Simple columnar

Stratified Epithelium – Multiple Layers Pseudostratified – Single Layer but

appears stratified Pseudo means “false”

•Goblet Cells

•Nose to Large Bronchioles

•Secrete mucus

Stratified Squamous Stratified Squamous EpitheliumEpithelium

Associated with PROTECTION Anterior portion of nasal cavity Oral cavity Oropharynx Laryngopharynx

Pseudostratified Columnar Pseudostratified Columnar EpitheliumEpithelium

SECRETION OF AND SWEEPING OF MUCUS

Posterior 2/3 of nose Tracheobronchial tree Function of cilia

Simple Cuboidal EpitheliumSimple Cuboidal Epithelium

PRIMARY FUNCTION IS SECRETION, FILTRATION & ABSORPTION

Bronchioles Clara Cells

Non-ciliated cells that secrete “surface-active agents” which prevent collapse.

Simple Cuboidal also found in alveoli (Type II cells that secrete surfactant)

Simple Squamous Simple Squamous EpitheliumEpithelium

PRIMARY FUNCTION – GAS EXCHANGE

Alveoli (Type I pneumocytes) Pulmonary capillaries

Upper AirwayUpper Airway

Anatomy Nose Oral Cavity Pharynx

Throat

Upper AirwayUpper Airway

Function of the Upper Airway Conduct Air To prevent foreign materials from entering

the lower airway Smell/Speech

NoseNose

Function Heat, Humidify and Filter the incoming gas Smell Speech

Anatomy of the NoseAnatomy of the Nose Bone and Cartilage Partition in the nose is called the nasal septum Air enters through the nostrils or nares Two nasal passages are called choanae Vibrissae filter the incoming gas

Whiskers First 1/3 is stratified squamous epithelium (PROTECTION)

Posterior 2/3 is pseudostratified ciliated columnar epithelium (MUCUS SECRETION)

Anatomy of the NoseAnatomy of the Nose

Mucous secreting glands are found in the posterior 2/3 of nose

Bony Protrusions on the lateral wall are called nasal turbinates or conchae Separate incoming gas into turbulent

airstreams – more contact Extensive capillary network

Constrict or dilate to change blood flow

Nasal ConchaeNasal Conchae

Deviated SeptumDeviated Septum

The nasal septum can be deviated to the right or left More often to

the left

Rhinitis: Inflammation of the nasal membrane

20% of Population

$5.3 Billion/Year

Physiology of the NosePhysiology of the Nose

Nose can filter particles down to 5 microns in diameter

Two factors which decrease the humidification and filtering ability of the nose is: Mouth Breathing Placement of an ET (endotracheal) tube

Paranasal SinusesParanasal Sinuses

Empty air spaces found in the bones of the skull; Paired Frontal Ethmoid Sphenoid Maxillary

They contain mucous secreting goblet cells which drain into the nasal cavity

Nose and Nasal CavitiesNose and Nasal Cavities

Anatomy of the Oral CavityAnatomy of the Oral Cavity

Roof of the mouth is formed by the hard and soft palate Hard – Bony portion Soft – Fleshy portion

Uvula is the soft fleshy structure Epithelium is stratified squamous

epithelium which is non-ciliated. Palatine (faucial) tonsils are located on

each side of the oral cavity.

TONSILSTONSILS

Pharynx - ThroatPharynx - Throat

Nasopharynx Oropharynx Laryngopharynx

NasopharynxNasopharynx

Located posterior to nasal cavity

Pseudostratified ciliated columnar epithelium

Includes pharyngeal tonsils or adenoids

Eustachian Tubes (auditory tubes) Connects the middle ear and

nasopharynx Middle ear infection is called

otitis media Complication of ET tubes

OropharynxOropharynx

Lies behind the oral cavity

Lingual tonsils lie at the root of the tongue

Statified squamous epithelium

LaryngopharynxLaryngopharynx

Lies between the base of the tongue and the entrance to the esophagus

Lies posterior to the epiglottis

Stratified squamous epithelium

aka Hypopharynx