UPPER AND LOWER RESPIRATORY TRACT

Anatomy

The branch of science concerned with the bodily

structure of humans, animals, and other living

organisms,

Air passages

From nose to bronchioles

Endotracheal tubes

an artificial airway that is used during surgery and critical care to deliver anesthetic gases, medications

and maintain vital respiratory gas support

Nose to thoracic inlet

Upper airway

Trachea to alveoli

Lower airway

Mouth breathing

used to decrease resistive gas flows at higher ventilation rates when the body requires it

Passage of gas, Filtration, Heating and Humidification, Phonation, Immune Defense, Sense of smell and taste

Functions of the URT include

8 to 40C to 32 to 34C

Temperature converted during heating and humidification by the nose

VIBRISSAE 

functions as filters against particulate that will enter the airway and minimizes entrance of foreign bodies

Nasal Septum

Perpendicular plate of the ethmoid bone descending from the vomer, separates the nasal cavity into left and right

Turbinates

(aka. Conchae) increase surfae area and work as a passageway, filter, heater and humidifier

Meatuses

scroll-like spaces between the bones

Paranasal Sinuses

reduce the weight of the skull and drain through apertures in the lateral walls of the nose. In the case of prolonged nasal intubation, the maxillary sinus may become infected

Venous Plexus

is an extensive network of veins

that supply water and heat to the nasal cavity.

Little’s area

anastomosis of vessels (Kiesselbach’s plexus)

When there is inflammation due to infection, allergic reaction, etc = there may be partial or complete blockage of air passage

Anterior ethmoidal artery, Posterior ethmoidal artery, Sphenopalatine artery, Greater palatine artery, Septal branch of the superior labial artery

Arteries Present in the anterior nasal septum

Olfactory area

Upper 1/3 of the nasal fossa

Consist of the middle and outer septum and superior turbinate bone

Paired paranasal sinuses

Sphenoid, ethmoid, maxillary, frontal Drain through the apertures into the lateral wall of the nose

Olfactory area

Upper 1/3 of the nasal fossa

Consist of the middle and outer septum and superior turbinate bone

Olfactory cells have specialised hairlike processed called olfactory innervated by olfactory nerve

Upper 1/3 of the nasal fossa

Location of Olfactory Area

Stratified squamous cells with hair follicles and hair

Anterior epithelial cell

Ciliated Psuedostratified columnar epithelium and goblet cells

Middle epithelial cell

Stratified squamous epithelium

Posterior epithelial cell

Soft palate and uvula

Posterior Part of the oral cavity

Hard palate (Maxillary Bone)

Anterior Part of the oral cavity

Cheeks

Lateral Part of the oral cavity

Tongue

Floor Part of the oral cavity

Vagal Gag Reflex

protects the lungs from aspiration.

Pharynx

Base of the skull to the level of the cricoid cartilage (ant) and inferior border of the 6^th cervial vertebra (posterior)

12 to 15cm

Measurement of the pharynx

Nasopharynx

v >10um particles are removed by inertial impaction on the posterior ___

v inhaled airstream direction changes of 90 degrees causes momentum loss for some particles and are trapped by the pharyngeal walls and circularly arrayaed by lymphoid tissue @ entrance of respiratory and alimentary tracts (rign of Waldeyer)

>10um

size of particles that are removed by inertial impaction on the posterior nasopharynx

Oropharynx

v Digestive in function

v From the soft palate and extends to the superior edge of the epiglottis

glossopharyngeus muscle

Anterior pillar

Palatoglossus

Posterior pillar

External Circular layer

advance food in a coordinated fashion from oropharynx into esophagus. Innervated by filaments arising from pharyngeal plexus

Internal longitudinal layer 

raises pharynx and opens auditory tube, which equalizes the ear during swallowing

Stylopharyngeus, Salpingopharyngeus ,Palatopharyngeus

The three muscle layers that composes the Internal layer (Elevate the pharynx and shorten the larynx during deglutition

Laryngopharynx

Aka hypopharynx

Between the 4^th and 6^th cervical vertebrae

From superior border of epiglottis and extends to inferior border of cricoid cartilage where it narrows and becomes continous with the esophagus

Between the 4th and 6th cervical vertebrae

Location of the laryngopharynx

Eustachian tubes

pen into the lateral walls of the nasopharynx, connects to the auditory tubes to equalize pressure

Tonsils

v May impede the passage of artificial airways when infected or enlarged

Lingual tonsillar hypertrophy

he enlargement of the lingual tonsils, which are located at the base of the tongue

Sepsis

if originating from the lymphoid aggregates may lead to retropharyngeal or pertionsillar abscess

Cilliary activity

Clears trapped nonsoluble particles

Upper airway obstruction

Typically believed to be caused by genioglossus muscle activity leading to posterior displacement of the tongue

Obstructive Sleep Apnea

when the muscles that support the soft tissues in your throat, such as your tongue and soft palate, temporarily relax.

Retropalatal, retroglossal, retroepiglottic

Collapsible Segments of the upper airways

Tensor palatini

retracts soft palate away from posterior pharyngeal wall

Genioglossus

moves tongue anteriorly

Geniohyoid, sternoihyoid, thyrohyoid

move hyoid bone forward

Continuous Positive Airway Pressure

Increases the volume and cross-sectional area of the upper airway, keeping it open

Larynx

v Lies in the adult neck opposite to the 3^rd to 6^th cervical vertebrae

v No difference between males and females until puberty

v Crossroads between food and air

v Watchdog of the respiratory tract

v Organ of phonation

Opposite to the 3rd and 6th cervical vertebrae

Location of the Larynx

44,36,43mm

Length, transverse diameter, saggital diameter of males

41,36,26mm

Length, transverse diameter, saggital diameter of females

Hyoid bone

n suspends and anchors the larynx respiratory and phonatory movement

n U-shaped bone

2.5cm wide x 1cm thick

Dimensions of the hyoid bone

Thyroid, Cricoid, Arytenoid

Cartilages of the larynx that are made up of HYALINE

Corniculate, Cuneiform, Epiglottis

Cartilages of the larynx that are made up of ELASTIC CARTILAGE

Thyroid

v Unpaired, made of hyaline

v Longest laryngeal cartilage and largestr structure in the larynx

v Shieldlike shape - embyologic midline fusion of the two distinct quadrilateral laminae

90 degrees

Angle of the thyroid cartilage of MALES

120 degrees

Angle of the thyroid cartilage of FEMALES

Thyroid notch

Lies in the midline at the top of the fusion site of two laminae

Cricothyroid joint

v Rotation and gliding

n Changes lengths of the vocal cords

Cricoarytenoid and cricotyroid

ball and socket

Arytenoids

cricoarytenoid arthritis

a life threatening airway obstruction (may also induce hoarseness or loss of voice)

Epiglottis

Vallecula

n Found at the base of the tongue

n Landmark for intubation

n Pouch between the median glossoepiglotic fold and lateral pharyngoepiglottic fold

Cuneiform and corniculate

v Elastic, paired

v Helps reinforce and support the aryepiglottic folds and help the arytenoids move

v Cuneiform is sesamoid shape and roughly cylindrical, antersuperior to the corniculate

v Corniculate is a small triangular object visible directly over the arytenoid cartilage

v Sesamoid: like a sesame seed - oval shaped