Basic Airway /Advanced Airway Flashcards
Problems that can occur in association with difficult airway
Dental damage pulmonary aspiration airway trauma unanticipated trach anoxic brain injury cardiopulmonary arrest
The upper and lower airway is divided where?
cricord cartilage
5 parts of upper airway
Nose mouth pharynx hypopharynx larynx
6 parts of lower airway
Trachea Bronchi Bronchioles terminal brinchioles respiratory bronchioles alveoli
Function of the nose
warm and humidify air
primary source of filtration
Anatomy of the mouth/oral cavity
Hard palate soft palate tongue Uvula tonsils
What structure of the mouth is at high risk for obstruction
tongue
Parts of the pharynx
Nasopharynx
oropharynx
hypopharynx
What are S/S of SLN injury, both unilateral and bilateral
Unilateral- minimal ( no real signs)
Bilateral- hoarseness
What are S/S of RLN injury, both unilateral and bilateral (acute and chronic)
Unilateral- Hoarseness
Bilateral-
—Acute-stridor, resp distress
– Chronic- Aphonia
3 paired cartilages that make up the larynx
- 2 arytenoids
- 2 corniculate
- 2 cuneiform
Vallecula
Space between the epiglottis and base of the tongue
2 types of muscles in the larynx
Intrinsic
extrinsic
What do the intrinsic muscles of the larynx do
control of vocal cords
opening and closing of the glottis
What do the extrinsic muscles of the larynx do
- connect larnyx with the hyoid bone and other structure
- adjust position of trachea for phonation, breathing, and swollowing
How long is the adult trachea
10-20 cm
What is the only cartilage with a complete ring in the trachea
Cricord ring
What is pertinent to airway assessment (questions to ask or look up; not physical)
- prior sx or hx of intubation/trach
- pror hx of diff intubation
- Hx of OSA
- Hx of oral, pharyngeal, esophageal disease
- trauma, burns, chemicals, radiation exposure to neck
S/S that indicate a pt has an increased risk for aspiration
- Loss of airway reflex
- LOC
- full stomach
- obese, pregnant, hiatial hernia
- GERD
- Decrease GI motility (DM, Trauma)
- volume > 25 ml (ph < 2.5)
Mendelson Syndrome
chemical pneuminitis due to the parenchymal inflammatory reaction caused by a large volume of gastric contents in lungs from aspiration ( independent of infection)
Ways to decrease risk of aspiration
- NPO
- Block histamine release (H2 blockers)
- increase gastric PH (antacids)
- Increase GI motility (reglan)
- use caution with sedationa and opiods
- ETT vs LMA
- RSI vs awake FOI
- Awake vs deep extubation
Liter flow rates and Fi02 delivered
Nasal cannula
Simple face mask
Non-rebreather
NC- 1-6 LPM / 24-44%
SFM- 5-12 LPM / 30-85%
NRB- 10-15 LPM / 60-85%
4 techniques to manipulate head, neck, and jaw for airway patency
- chin lift
- head tilt and chin lift
- Jaw thrust
- Hyperextension of Neck (head tilt)
3 axis to align for maximal exposure with intubation
- Oral axis
- pharyngeal axis
- laryngeal axis
3 main types of LMAs
Classic
Proseal
Fast track
What is unique about the proseal LMA
-drain tube
What is unique about the fast track LMA
Allows you to place an OETT
has an epiglottis flap
Tracheal intubation is recommended when?
- compromised airway
- long procedures
- procedures of head/neck/chest/abd
- Need for positive pressure ventilation
- inability to maintain mask ventilation
- disease of the airway
- risk of aspiration
What are indications for Awake FOI
- anticipated difficult airway
- unstable neck fx
- Halo
- small / limited oral opening
- critical care settings
What airway structures are most vulnerable to injury during intubation
arytenoids
posterior half of vocal cords
posterior tracheal wall
What can occur up to 3 hours post extubation
Croup
LMA size compared to weight and max inflation (only adult sizes)
LMA size Weight MAX inflate #3 30-50kg 20 ml #4 50-70kg 30 ml #5 70-100kg 40 ml #6 >100kg 50 ml * how to remember the max inflate for test- minus 1 and add 0 to the size. ex #3 -1=2 add 0 = 20 ml
What muscle acts as a barrier to regurgitation in conscious Pts.
cricopharyngeos muscle
Extubation criteria
- adequate TV and rate
- open eyes to commands no diplopia
- sustained protrusion and purposeful movements of the tongue
- effective swollow
- head lift >5 sec
- effective cough
- sustained titanic response to 50 hrz for 5 sec’s
- TOF > 90 ratio with NO fade
Whats the difference in airway resistance between the nasopharynx and oropharynx
the resistance to airflow through the nasopharynx is twice that of the oropharynx and accounts for about 2/3rds of the total airway resistance
Disadvantages of oropharyngeal airways
- cut lips, tongue, oral mucose
- Can cause a gag reflex
- obstruction of glottis (if to large)
- Push tongue posterior and cause obstruction (if too small)
Advantages of oropharyngeal airways
- air can pass around or through
- keeps teeth/lips open
Advantages of nasopharyngeal airways
- better tolerated in light planes
- prefered with pts with limited mouth openings or dental caries
Disadvantages of nasopharyngeal airway
nose bleeds
-contraindicated with coagupathies and basilar skull fx
LMA contraindications
- pharyngeal pathology
- pharyngeal obstruction
- full stomach
- decreased pulmonary compliance (RAD), that requires > 30 cmH20 pressure
What LMA is designed for anticipated difficult airways situations and CPR, b/c it can facilitate continuous ventilation during intubation
Fast track
Which LMA is a reusable airway that has a cuff made of softer material than the classic, it is designed to conform to the hypopharynyx, although it can be used with spont breathing pts, it is designed for PPV with or without muscle relaxants
proseal
How do you confirm appropriate tracheal intubation
MOST RELIABLE - end tidal CO2
PCO2 > 30 mmhg for 3-5 breaths
S/S ETT not olaced correctly
- no rise in CO2
- decrease O2 sat
- Unilateral breath sounds
- inability to palpate ETT cuff @ sternal notch
- Increased Peak Pressures
- Tachycardia
Afferent is _____ and carries nerve impulses _____?
Sensory
carries impulses to the CNS
Efferent is _____ and carries nerve impulses ________?
Motor
carries impulses away from CNS to periphery
Mallampatti I
Hard palate Soft palate tonsillar fauces tonsilar pillars uvula
Mallampatti II
Hard palate
Soft palate
tonsilar fauces
uvula
Mallampatti III
Hard palate
Soft palate
base of uvula
Mallampatti IV
Hard palate
Cormack and Lehane Gade I
Entire laryngeal aperature
Cormack and Lehane Gade II
posterior portion of laryngeal aperature only
Cormack and Lehane Gade III
epiglottis only
Cormack and Lehane Gade IV
soft palate only
Unilateral RLN injury causes what
hoarsness
NPO fasting guidelines
clear liquids -2hours
Breast milk- 4 hours
everything else @ least 6 hours
The antacid sodium citrate (bicitra) has what disadvantage
increased gastric volume
ASA Scores
I- Normal healthy adult
II- Pt with mild systemic disease
III- pt with severe systemic disease
IV- pt with severe systemic disease THAT IS A CONSTANT THREAT TO LIFE
V- morbid pt who is not suspected to live without Sx
VI- brain dead/ organ donor
Four Ds that make a difficult airway
dentation
distortion
disproportion
dysmobility
what mallampatti scores are good
I-II
3 single cartilages that make up the larynx
thyroid
cricoid
epiglottis
What does the external SLN innervate
motor fxn to cricothyroid muscle of larynx
What 2 things does the RLN innervate
- sensory innervation to the subglottic area and trachea
- motor to all muscles of larynyx EXCEPT cricothyroid
The SLN divides into what?
Internal and external SLN
What does the internal SLN innervate
sensory input above the cords
The vagus nerve branches into what in the pharynx
Superior laryngeal nerve (SLN)
Recurrent Laryngeal Nerve (RLN)
The MOTOR response of the pharynx that Results in a gag is what nerve
CN X- (Vagus nerve)
SENSORY response elicited when the posterior wall of pharynx is touched and stimulated are carried to the brain by what nerve
Glossopharyngeal (CN IX)
Difficult intubation is defined as what
3 or more attempts
more than 10 minutes
Difficult mask ventilation is defined as what
inability to maintain SPO2 > 90% or signs of inadequate ventilation
The nasopharynx is separated from the oropharynx by what
soft palate
The oropharynx is separated from the hypopharynx by what
epiglottis
The trachea begins and ends where
C6-T5 (the carina)
How many horseshoe shaped cartilages make up the trachea
16-20
What supplies the infraglottic region and comes off of the inferior thyroid artery
Inferior laryngeal artery
What supplies the supraglottic region of the larynx, comes from the superior thyroid artery
superior laryngeal artery
What part of the oral cavity remains stationary
hard palate
What part of the mouth covers the posterior 3rd to half of the oral cavity, rises during eating to prevent passage of contents into the nasal passage way
soft palate
What part of the mouth guards the passageway from the oral cavity to the oropharynx
uvula
What structure of the mouth is walnut shaped and sits on both sides of the posterior opening of the oral cavity
tonsils
Function of the larynx
- protect airway from aspiration
- provide airflow b/t hypopharynx and trachea
- cough and gag reflex
- phanation
5 intrinsic muscles of the larynx
posterior cricoarytenoid lateral crioarytenoid arytenoids cricothyroid thyroarytenoid
Common physical assessments for airway
interincisor gap thyromental distance head and neck extension mallampatti body weight
what is the best/ideal way to determine a difficult airway
there isn’t one dummy!!!
Signs that may indicate a pt will be a difficult mask ventilation
elderly endentulous obese snores/ OSA bearded (RTFF) stridor
Difficult airway adjuncts
blades fiberopticscope lightwand bullard scope LMA stylet retrograde intubation bougie TTJV combitube
What do the intrinsic muscles of the larynx do
control the tension of the vocal cords and the opening and closing of the glottis
What is the ideal BVM positioning
aligning the external auditory meatus with the sternal notch
How do you break a laryngospasm
- positive pressure
- anesthestic gasses
- 10-20 mg sux’s
- lidocaine
- push on trigger point in sternocleido muscle
If not treated with positive pressure the laryngospasm can cause what
negative pressure pulmonary edema
Why would you never wake a pt is stage II anesthesia
will cause laryngospams
Per the literature what adjunctive tool is most superior for difficult airways
Awake-FOI
Per real life what adjunctive tool is most superior for difficult airways
the one you are most comfortable using
How do you prepare for a nasal intubation
- prep with astringent (afrin or neosynephrin)
- dialate nares with progressive lubricated nasal trumpets
- Introduce and advance the ETT
Steps for an Awake-FOI
- discuss steps with pt
- local anesthetic
- antisialogoue
- monitors, 02, sedation
- semi-fowlers or supine
- insert ETT
- advance Fiberoptic
- identify anatomy
- advance through cords
- go till you see the carina
- advance ETT over fiberoptic
- withdraw fiberoptic
- conform with ETCO2
- IV or inhalation induction
What is important about sedation during an awake-FOI
sedation should not obtund the protective reflexes of pt
Sedation choices for awake-FOI
midazolem
fentanyl
dexmetomodine
How should you extubate the difficult to intubate pt
awake and responsive good grip/ head lift sustained adequate reversal NIF > 20mmhg (neg inspiratory force) VC> 15 ml/kg (vital capacity)
Can’t ventilate + can’t intubate = what
sugical airway
What must you remember about TTJV
- MUST USE INTERMEDIATE PRESSURE 02 SUPPLY
- allow time for expiration (1:4)
- risk of barotrauma
- buys the anesthesia team time before surgical airway
Why do we use RSI
for pt’swho are at increased risk for aspiration requireing minimal time with an unrotected airway
Steps for RSI
- aspiration prophylaxis
- airway eqipment - suction
- optimize intubation conditions
- denitrogenate
- STP + Sux IV push
- proper cricord pressure
- no bag ventilation
- intubate
- on emergence- awake extubation
What 3 intrinsic muscles are responsible for laryngospasms
lateral cricoarytnoid
cricothyroid
thyroarytnoid
remember CAT
