airway management Flashcards
Airway (6)
upper airway which consit of the oral and nasal cavities, pharynx, larynx, trachea, and principal bronchi
- Components of the upper airway (5)
- Other anatomy
Components of the upper airway:
Nose Nasopharynx Oropharynx Laryngopharynx Larynx
Other anatomy: Hard palate soft palate tongue palatine tonsil epiglottis vocal folds esophagus trachea
the nose:
- where does it begin and where does it end?
- how many cm in adults?
- what are the functions?
-the airway begins at the nares
-functions:
air movement, humidification, olfaction, filtration, phonation
-nostrils to nasopharynx:
10-14cm in adult
-the primary pathway for normal breathing unless obstruction is present
-quiet breathing:
resistance to airflow through nasal passages accounts for almost 2/3 of total airway resistance
resistance through the nose is almost 2X that associated with mouth breathing
Naso-pharynx:
-sensory innervation of the nasal mucosa arises where?
Know name of nerve and what it supplies:
Know the areas that are innervated by nerves from where:
Know about how local anesesthesia blocks certain nerves:
The sensory innervation of the nasal mucosa arises from 2 divisions of the trigeminal nerve:
-anterior:
ethmoidal nerve supplies the anterior septum and lateral wall
-posterior areas:
are innervated by nasopalatine nerves from the sphenoplatine ganglion
local anesthesia:
block anterior ethmoidal and maxillary nerves bilaterally- OR- simple topical anesthesia of the nasal mucosa is usually effective
turbinates
cribriform plate of ethmoid spheno-ethmoidal recess superior concha middle concha inferior concha inferior meatus vestibule
Nasal anatomy:
- Blood supply (4)
- Nerve supply (4)
*Blood supply:
-opthalmic artery:
supplies blood to the upper part of nasal cavity
branches of maxillary artery:
supplies blood to the lower part of nasal cavity
Kiesselbach’s plexus (vascular area) anteromedial septum:
most epistaxis comes from this area because four small arteries anastomose here
Large submucous venous plexus
- Nerve supply:
- olfactory
- 1st division of V (opthalmic nerve)
- 2nd division of V (maxillary nerve)
- sphenopalatine ganglion (behind the turbinates)
nasal intubation:
- position and land marks
- nasal mucosa
- condtraindications (2)
-stay low-below inferior turbinate-parallel to hard palate and through channel below inferior turbinate
-nasal mucosa sensitive to topical vasoconstriction
–to blunt pain and sympathetic responses
-tube insertion can injure pharyngeal mucosa, dislocate turbinate
-eustachian tubes:
entrance blocked by nasal ETT- long term- risk of sinus infection
CONTRAINDICATIONS:
-basilar skull fracture, nasal fracture (can put tube through cribiform plate into brain)
pharyngeal anatomy (3) -where does it start and end
nasopharynx:
behind nasal cavity, above the soft palate
oropharynx:
soft palate to tip of epiglottis
laryngopharynx:
tip of epiglottis to lower border of cricoid cartilage, at level of C6
pharyngeal airway
- name the landmarks that it extends from
- describe retropharyngeal space
extends from the posterior aspect of the nose down to the cricoid cartilage, where the passage continues as the esophagus
extends from sphenoid bone to C-6
Retropharyngeal space permits free movement during gluition, and retropharyngeal abcess. can infiltrate through this space and enter the superior mediastinum
anatomy of pharynx muscles (4)
- genioglussus- protrudes tongue
- geniohyoid- displaces hyoid arch anterior
- sternohyoid-displaces hyoid arch anterior
- pharngeal constrictors- form lateral paryngeal walls
pharyngeal muscles:
- external:(3) What do these do?
- internal: (3) What do these do?
- nerve innervation (4)
- *Which nerve gives sensation and where?
external:
constrictors-superior, middle, and inferior
- advance food into the esophogus
internal:
stylopharyngeus, salpingopharyngeus, and palatoparyngeus
-elevate pharynx during degluition
nerve innervation:
glossopharyngeal, vagus, recurrent and external laryngeal
-glossopharyngeal nerve-sensation to back 1/3 of tongue, valleculae, superior surface of epiglottis, most of posterior pharynx
pharynx:
-normal pharyngeal muscle tone:
- decreased by sedation
- lost by neuromuscular blockade
- lost by general anesthesia
upper airway obstruction
- loss of muscle tone (2):
- order of importance of obstructing tissue (3):
- head extension and jaw thrust move
- jaw thrust will move
- mechanisms of pharyngeal tube collapse
- resolution to obstruction
-loss of muscle tone:
pharyngeal wall and tongue
-order of importance of obstructing tissue:
soft palate, epiglottis, and tongue
- head extension and jaw thrust move hyoid anteriorly
- jaw thrust will move epiglottis in slim but not obese patients
- lateral positioning also helps by moving obstructing tissue downward
- intervening pharyngeal tube can collapse due to muscle tone and flow though the collapsible segment depends on how the intraluminal pressure upstream and downstream relate to the tissue pressure around the pharynx. Nasal airways and nasal CPAP help this obstruction dynamic
anatomy of oral cavity (8)
rugae median raphe hard palate velum uvula ant faucial pillar palatine tonsils post faucial pillar
oropharynx complications that may make intubation challenging (3)
- tmj must permit adequate mouth opening
- high arched palate, or protruding dentition may mean difficult intubaton
- tongue must be moved into submandibular space by blade during intubation..space too small or narrowed, intubation may be difficult
pharynx in OSA:
- obstruction landmarks (2)
- what happens to the airway caliber
- how to acheive patency
- obstruction from soft palate as well as tongue
- reduced airway caliber, alteration is airway shape
- need pharyngeal dilator muscle tone for patency
tongue anatomy:
- what type of organ?
- covered by?
- extends from?
- muscular organ in the mouth, the primary organ of taste
- is covered by a mucous membrane, extends from the hyoid bone at the back of the mouth upward and forward to the lips
