Respiratory Flashcards
Functions of the larynx
Phonation, respiration, airway protection
How do the blades work around the valeculla
Mac blade - slides into vallecula and will pull epiglottis forward.
Miller blade - actually picks up the epiglottis
Where is the larynx located?
Cervical vertebrae 3-6
How do the vocal chords attach?
Angles of the thyroid (A) and the arytenoids (P)
Narrowest point of the airway in adult and child
Pediatric - cricoid cartilage
Adult - glottic opening
List the 9 cartilages of the larynx
2 arytenoid 2 cuneiform 2 corniculate Thyroid Cricoid Epiglottis
Describe laryngeal intrinsic muscle innervation
Recurrent laryngeal nerve via CN X
Except for the cricothyroid muscle which is innervated by the external branch of the superior laryngeal nerve
Innervation of the tongue
Back 1/3 of tongue gets supply from CN IX (glossopharyngeal)
Innervation of the nasopharynx
CN V (trigeminal)
Muscles that open and close the glottis
Lateral cricoarytenoids - adduct
Arytenoids - adduct
Posterior cricoarytenoids - aBduct
Muscles that put tension on the vocal cords
Cricothyroid - elongates vocal cords
Vocalis - shortens vocal cords
Thyroarytenoid - shortens vocal cords
List extrinsic laryngeal muscles
Sternohyoid, omohyoid, thyrohyoid
The move the larynx as a whole
Level of the carina
5th cervical vertebrae.
Angles of trachea bifurcation
R side - 25 degrees
L side - 45 degrees
PMH to ask about pre-op
Radiation to head and neck Burns to head or neck C-spine problems TMJ pain RA Abscess or tumors Prior intubation or tracheotomy Dysphasia or stridor Snoring or OSA Ankylosing spondylitis
Steps for mallampati evaluation
Sit upright Neck neutral Open mouth Stick tongue out far Don't say AH
What’s a good thyromental distance
4 finger breadths or 6-6.5mm
what is the risk of using a head strap during intubation?
May cause facial nerve palsies with nerve compression
what does the sniffing position do?
aligns all all three axis: oral, pharyngeal, laryngeal
what is the goal of supplemental oxygen pre-intubation?
increased the FRC of Oxygen and decrease the nitrogen in FRC
during RSI, how can you pre-oxygenate?
4 vital capacity breaths in 30 seconds
How long should you give O2 in a normal pre-surgical intubation?
3-5 minutes of 100% O2 at >5L/min
what size tube can you place over an #4 LMA?
6 OETT
what is a major complication of oral airways?
LARYNGOSPASM, bleeding, soft tissue damage
what are some contraindications to nasal airway insertion?
epistaxis, nasal trauma, basal skull fractures, anticoagulation, adenoid hypertrophy
How far down do you want your OETT to be?
4 cm above the carina, 2 cm below the vocal cords
about 23 cm in males and 21 cm in females
what are is the sensory innervation of the airway?
glossopharyngeal (back 1/3 of the tongue), recurrent laryngeal, internal branch of the superior laryngeal
What is the motor innervation of the airway?
external branch of the superior laryngeal nerve (above the cords), recurrent laryngeal nerve (below the cords)
what are some major complications of tracheal intubation?
trauma to airways, esophageal intubation, laryngospasm, sore throat, endobronchial intubation
what is the induction sequence for tracheal intubation?
pre-oxygenation, sniffing position, monitors, induction agent, test ventilation, paralytic drug, eyes taped, mask-bag ventilation until muscle movement stops, laryngoscopy, intubate, confirm ETT placement with bilateral breath sounds and ETCO2, ventilate with bag or machine, maintenance anesthetic, tape OETT
what is a major indication for an airway block?
an awake intubation and/or a suspected difficult airway
what are 2 major complications for airway blocks?
systemic toxicity and hematoma formation
what does a transtracheal block do?
blockes RLN
anesthesia below the vocal cords
through the cricothyroid membrane
What does a superior laryngeal block do?
blocks internal SLN and the supraglottic region
goes through the thyrohyoid membrane
What anatomical landmark are you looking for in a SLN block?
the cornu of the hyoid bone.
Then go 1/4 inch caudal and 1/4 inch medial
What spread transtracheal anesthesia?
coughing
what is one important feature of SLN blocks?
they need to be done bilaterally
When would you do a glossopharyngeal nerve block?
when local anesthetic on the back of the throat is not enough
what should you aspirate during a glossopharyngeal block?
nothing… if you get air, you’re too deep
if you get blood, pull needle out and redirect medially
What is a common alternative to a glossopharyngeal block?
nebulized lidocaine
