Airway Intro Flashcards
Nasal passages include 3
Septum, turbinates, adenoids
Nasal passages function: 4
2/3 of upper airway resistance, humidify, filter, warm
Nasal passage innervation
Branches of CN V trigeminal
Oral cavity include 4
Teeth, tongue, hard palate, soft palate
What is predominate cause of airway resistance in oral cavity
Tongue
Oral cavity innervation
Trigeminal nerve: hard palate, soft palate, ant 2/3 of tongue
Glossopharyneal: posterior 1/3 tongue, soft palate, oropharynx
What connects nasal and oral cavities to larynx and esophagus
Pharynx
Pharynx divided into: ____, border of soft palate. ___ border is epiglottis, includes tonsils and uvula. Also ___/___
Nasopharynx
Oropharynx
Hypopharynx/laryngopharynx
Innervation of pharynx
CN 9 and 10
Larynx
Located where in adult
Functions 3
C4-C6
Airway protection, respiration, phonation
Larynx composed of ___ ___ and ___ __ which is fissure between
Vocal cords and glottic opening
Vocal cords: formed by ___ ligament, attached anteriorly to ___ cartilage and posteriorly to ___ cartilages
Thyroartyenoid
Thyroid
Artyenoid
What is the triangular fissure between vocal cords
Glottic opening
What is narrowest part of adult airway
Glottic opening
Paired cartilages larynx
Arytenoid, corniculate, cuneiform
Unpaired cartilage in larynx
Thyroid, cricoid, epiglottis
Arytenoid: ___ attachment for vocal cords. Falsely identified in an __ __
Posterior, anterior airway
Corniculate: ___ portion of the ___ fold
Posterior, aryepiglottic
Cuneiform: in the ___ fold but not always ___. Lateral to ___
Aryepiglottic, present
Corniculates
Which cartilage is large, most prominent, and anterior attachment for vocal cords
Thyroid
Epiglottis: covers opening to ___ during swallowing
Larynx
Only complete signet shaped ring, narrowest part of peds airway
Cricoid cartilage
Which muscles control length and tension of vocal cords, and size of glottic opening
Intrinsic laryngeal muscles
Cricothyroid muscle innervated by the ___ branch of the __ __ nerve and a branch of the __ nerve
External
Superior laryngeal
Vagus
All intrinsic laryngeal muscles except for ___ innervated by __ __ nerve, branch of __ nerve
Cricothyroid
Recurrent laryngeal
Vagus
Which muscles adduct vocal cords
Lateral cricoarytenoid, oblique and transverse arytenoids
Which is only vocal cord abductor
Posterior cricoarytenoid
Cricothyroid action
Tenses and elongates vocal cords
Thyroarytenoid action
Relaxes and shortens vocal cords
Vocalis action
Relaxes and shortens vocal cords
Action of extrinsic laryngeal muscles
As a whole move larynx cephalad or caudad
Suprahyoid group
4
Action
Stylohyoid, mylohyoid, geniohyoid, digastric
Raises larynx cephalad
Infrahyoid group
4
Action
Sternothyroid, sternohyoid, thyrohyoid, omohyoid
Moves larynx caudad
Functions of branches of trigemincal nerve
Ophthalmic
Maxillary
Mandibular
Sensory to nares and anterior nasal septum
Sensory to turbinates and posterior nasal septum
Sensory to ant 2/3 tongue, motor to mastication muscles
Glossopharyngeal nerve
Sensory and motor to what
Sensory to soft palate, oropharynx, post 1/3 tongue, tonsils, vallecula, topside of epiglottis
Motor to stylopharyngeus
Vagus nerve
Superior laryngeal nerve
External branch innervates what
Internal branch innervates what
Motor to cricothyroid, sensory to ant subglottic mucosa
Sensory of posterior epiglottis to VC, thyroepiglottic joint, and cricothyroid joint
Vagus nerve
Recurrent laryngeal nerve
Innervates what
Motor to all intrinsic laryngeal muscles except cricothyroid
Sensory below VC, trachea
Injury to external branch of superior laryngeal nerve:
Action
through what
leads to what
Tensing vocal cords through cricothyroid
Thyroidectomy
Hoarseness
Injury to recurrent laryngeal nerve
Controls what
About chronic unilateral injury
All other intrinsic muscles like posterior cricoarytenoids
Generally well tolerated
Injury to recurrent laryngeal nerve
Acute bilateral injury leads to what
Bilateral paralysis of VC abductors (post cricoarytenoids), unopposed tensing of cricothyroid, strider and respiratory distress
Recurrent laryngeal nerve
Unilateral injury leads to what
Paralysis of ipsilateral vocal cord abductors, no airway emergency
Parts of lower airway
Trachea, carina, bronchi, bronchioles, terminal bronchioles, respiratory bronchioles, alveoli
Trachea
__-__ __ length
___ __ diameter in adult
10-20
22
Trachea
How many u shaped cartilages
Posterior side lacks what
Bifurcated where
16-20
Cartilage
T4
Right bronchi is __ __ long with angle of __
Left bronchi is __ __ long with angle of __
2.5 cm, 25 degrees
5 cm, 45 degrees
What creates a difficult airway
Not 1 factor, combination of factors
Questions to consider when evaluating airway 9
Radiation or burn to head or neck C spine pain of LROM TMJ pain Rheumatoid arthritis Ankylosing spondylitis Abscess or tumor Prior intubation or trach Snoring or sleep apnea Dysphagia or stridor
Mallampati score
Correlates __ space with ease of direct laryngoscopes and intubation
How to test
Oropharyngeal
Have pt sit up with neutral head and open mouth, stick tongue out, no aah
Mallampati
Class I
Class II
Faucial pillars, entire uvula, soft and hard palates
Uvula tip masked by tongue, soft and hard palates
Mallampati
III
IV
Soft and hard palates, uvula base only
Hard palate only
Score of laryngoscopic view of the glottis
Cormack and Lehane
Cormack and lehane score
Grade I
Grade II
I- most of glottis visible
II- only posterior portion of glottis visible
Cormack and lehane score
Grade III
Grade IV
III- only epiglottis visible
IV- no airway structures visualized
Thyromental distance
Distance from what to what with neck fully extended
Normal:
Difficult intubation if what
Lower border of mandible to thyroid notch
6-6.5 cm, 4 fingerbreadths
<3 fingers, receding mandible, anterior airway
What you need to prepare for induction
Monitors on, appropriate settings Suction on and at HOB Machine checked, means of PPV Airway IV Drugs- emergency and case specific
Airway set up
What you need on top of msmaids
Appropriate sized face mask, tongue depressor, oral and nasal airways, laryngoscope handle, 2 different blades, 2 size ETTs, stylet, syringe, LMA, tape
3 things that can make a mask hard to fit
Beard, edentulous (no teeth), short mandible
Goal of pre oxygenation
To increase O2 in functional residual capacity by washing out nitrogen (79% in RA) with oxygen
FRC is what
Volume of air left in lung at end of passive expiration
Doing what will lead to 10 minutes of safe apnea time
3-5 min of tight mask fit during normal tidal breathing with 100% fio2 at >6LPM flow
What leads to 5 minutes of safe apnea time
4 vital capacity breaths within 30 seconds w 100% fio2 at > 6LPM
Common problem in induction is airway obstruction by tongue and epiglottis due to relaxation of what
Genioglossus muscle
Two types of oral airways
Berman BOA
Guedel
Adult sizes of BOA and Guedel. Small, medium, large
S- 80 mm BOA, guedel 3
Med- 90 mm BOA, guedel 4
L- 100 mm BOA, guedel 5
Measure oral airway how
Center of mouth to angle of the jaw
Or from corner of the mouth to the earlobe
Complications of oral airways 3
Laryngospasm (if not asleep before placement)
Bleeding
Soft tissue damage
Nasal airway
Provides passage of nose to what
3 __ sizes:
Length estimates distance from nares to what
Pharynx
French 24, 26… 36
Meatus of eat
Nasal airway
Important for what
How to use, how its tolerated compared to oral
Used in series small to large, dilate prior if elective
Lubricate
Better
Nasal airway complications
If on anticoagulants
Epistaxis
Nasal or basal skull fractures
Adenoid hypertrophy
Dont use
Mac (__-__)
Miller (__-__)
1-4
0-4
ETT
Size for female
Size for male
Want what available
6.5-7 mm id
7.5-8 mm id
2 sizes
Ideal position ett
Males approx ___ cm, females __
How to calculate depth
23, 21
ID x 3
Optimal intubating position
Aligns what
Sniffing
Oral, pharyngeal, laryngeal axis
Sniffing position allows for what 2
Optimal visualization of vocal cords and most effective mask ventilation
How to get sniffing position normal adult
Pillow and tilt head back
How to get sniffing position if obese
Ramp up, bring chest cavity up by using pillows or blankets
LMA
___ airway device
Used for __ and __ ___ management
Can be used as conduit for what
Supra glottic
Routine and difficult airway
Ett placement
Appropriate sized lma based on what
Weight
Adult size lma 30-50 kg 50-70 kg 70-100 kg >100 kg
3
4
5
6