Week 2- AIRWAY Flashcards
Upper Airway
- Nasal Passages (septum, turbinates, adenoids, Paranasal sinuses)
- Oral Cavity (Teeth, tongue, HP, SP)
Function of Nasal Pasages
Upper Airway
- Accounts 2/3 total upper airway resistance
- Humidification
- Filter
- Warm
Innervation of the Nasal Pasages
Via Branches of Trigeminal Nerve CN V
Oral Cavity innervated by what CN?
- Trigeminal (CNV)- Sensory—-) Nose, chewing
- HP, SP
- Anterior 2/3 tongue
- Glossopharyngeal (CN IX)—) Swallow, Gag
- Posterior 1/3 tongue
- SP
- Oropharynx
Pharynx
- Nasopharynx (border= SP)
- Oropharynx (Border= Epiglottis, Tonsils, Uvula)
- Hypo/Laryngopharynx
Innervation of the Pharynx
- Glossopharyngeal (CN IX)
- Vagus (CN X)
-swallow, gag, sensation
Larynx
C4-C6 in adult
Functions:
- Airway protection (w/ epiglottis)
-Respiration
-PhonationCartilages of Larynx
9 Cartilages (3 paired) (3 Unpaired)
3 Paired Cartilages (Larynx)
- Arytenoid
- Cornice late
- Cuneiform
3 Unpaired Cartilages (Larynx)
- Thyroid
- Cricoid
- Epiglottis
Narrowest portion of the Adult Airway
-Glottic opening= Triangular fissure btn cords
Narrowest portion of Peds airway
Cricoid cartilage
Cricothyroid muscle innervated by what?
- External Branch of Superior Laryngeal Nerve
- This is branch of Vagus Nerve (CN X)
Intrinsic Laryngeal Muscles
Control mvts of laryngeal cartilages (length, and tension of vocal cords & size of Glottic opening)
-Besides Crycothyroid muscle….ALL other Intrinsic Laryngeal Muscles Innervated by: RECURRENT LARYNGEAL NERVE= branch of Vagus nerve (CN X)
Damage to nerves is caused by blocking __________ sides of the neck.
Both
Intrinsic Muscles of Larnyx and ACTION
ADD Table 23-1 pic from slides….
Lower Airway consists of:
- Trachea
- Carina
- Bronchi
- Bronchioles
- Terminal bronchioles
- Respiratory Bronchioles
- Alveoli
Trachea
- No Complete rings
- Fibromuscular tube
- Length:10-20cm
- Diameter: 22mm in Adult
- 16-20 Ushaped cartilages
- Posterior lacks cartilages
Trachea Bifurcates at what place?
T4- Carina
How long and what angle is Right bronchus?
Length:2.5cm
Angle: 25 degrees
How long and what angle is Left bronchus?
Length: 5cm
Angle: 45 Degrees
Mallampati Score
ADD PIC SLIDE 18
What does Mallampati Score predict?
Correlates the oropharyngeal space with the ease of
direct laryngoscopy and tracheal intubation
What happens when tongue is disproportionally large?
tongue overshadows the larynx resulting in
difficult exposure of the vocal cords during
laryngoscopy
Characteristics of Mallampati Class I (Remember PUSH)
faucial Pillars, entire Uvula, Soft and
Hard palates
Characteristics of Mallampati Class II
Uvula tip masked by tongue, Soft and
Hard palates
Characteristics of Mallampati Class III
Soft and Hard palates, uvula base
only
Characteristics of Mallampati Class IV
Hard palate only
Cormack and Lehane Score
-laryngoscopic view of the glottis
-Mallampati class is correlated to what can be
seen on direct laryngoscopy
Cormack and Lehane Score (Grade I-IV) What doe you see?
Grade I: most of the glottis visible
Grade II: Only the posterior portion of glottis visible
Grade III: Only epiglottis visible
Grade IV: No airway structures visualized
ADD PIC slide 21
Thyromental Distance
- Lower border mandible to thyroid notch with neck fully extended
- Normal: 6- 6.5cm or (4 FINGER BREADTHS)
- Difficult: (LESS THAN 3 FINGERS
Sniffing Position
- Aligns 3 axis (Oral Pharyngeal Laryngeal axis
- ADD PIC
Describe Airway set up
-Appropriate sized face mask*
- Means of Positive Pressure Ventilation (PPV)-> ambubag,
machine circuit
- Suction on and easily accessible
- Tongue depressor
- Appropriate sized oral and nasal airways*
- Laryngoscope handle*
- 2 different blades*
- Endotracheal Tube (ETT)- 2 sizes*
- Stylet
- Syringe
- Appropriate sized Laryngeal Mask Airway (LMA)
(difficult airway)*
- Tape
Describe Hand placement for Use of face masks
- Mask in Left Hand
- Reservoir Bag in Right
- Thumb on upper aspect of mask, index and middle fingerson lower aspect, and 4th/5th fingers under chin for chinlift/jaw thrust
What is a common problem with induction and why does it happen?
airway obstruction by the
tongue and epiglottis due to relaxation of the
genioglossus muscle
Order to correct issues with Airway patency…
- Airway Maneuvers
◦ Head tilt/chin lift
◦ Jaw Thrust - Adjuncts
◦ Nasopharyngeal Airway-lubricate
◦ Oralpharyngeal Airway-tongue blade
3. 2 handed mask with bagging assistance
Types of Oral Airways
Berman (BOA) and Guedel
How do you measure Oral Airway?
- From center of mouth to angle of jaw
- OR from mouth to earlobe
Complications/Precautions of Oral Aiways
Laryngospasm*
◦ Bleeding
◦ Soft tissue damage
- Pt must be unconscious (heavily sedated with NO GAG)
Describe process for Nasal trumpet airway insertion and sizing
-Must LUBRICATE
-Used in series (small to large) to dilate prior to
elective nasal intubation
Complications/Pxns for Nasal AIRWAY
-epistaxis, nasal or basal skull fractures, adenoid
hypertrophy, anticoagulants?
-BEST used in Light anesthesia
Laryngoscopes: Name 2 types…
- Macintosh (1-4)
- Miller (0-4)
Macintosh blade sits where when used to open airway?
Into the Valeculla
-Lifts epiglottis and folds up
Miller blade sits where when used to open airway?
Sits on top of epiglottis
***best used with stiff pediatric epiglottis
Ideal Position of the ETT?
4 cm above the carina and 2 cm below the vocal cords ( Males approximately 23 cm Females approximately 21 cm IDx3= approximate depth)
What will you ALWAYS do after ETT insertion?
ALWAYS Listen for bilateral breath sounds
-Look for bilateral chest rise and presence of end-tidal CO2!
What is the standard size Diameter for ETT connectors?
15mm outer diameter tip
Name some indications for Tracheal Intubation
◦ Airway compromise
◦ Airway inaccessible
◦ Long surgical time
◦ Surgery of head, neck, check, or abdomen
◦ Need for controlled ventilation and/or positive endexpiratory
pressure
◦ Inability to maintain airway with mask/LMA
◦ Aspiration risk
◦ Airway/ lung disease
LMA can be used for what kind of cases
Supraglottic airway device
–>Used for routine and difficult
airway management
Considerations for LMA usage
- Aspiration RISK
- Can be used as Conduit for ETT placement
- Placed blindly / Must be lubricated
- NOT MEANT for PPV (Must keep pressures <15)
LMA Sizing
- Appropriate Size is based on patient weight ◦ Adult sizes 30-50Kg--> LMA 3 50-70 Kg--> LMA 4 70-100 Kg--> LMA 5 >100 Kg--> LMA 6
Advantages for LMA over ETT
-Fast and ease of placement by inexperienced
personnel
-improved hemodynamic stability at induction and during emergence
-Decreased anesthetic requirements for airway tolerance
-Lower frequency of coughing during emergence
-Lower incidence of sore throats inadults (10% vs 30%)
- avoids “foreign body” in the trachea
**patient can be fully emerged prior to removal of LMA (good for asthmatic patients)
Disadvantages of LMA
- lower seal pressure
- higher frequency of gastricinsufflation
- esophageal reflux more likely
- inability to use mechanical ventilation*
Name some intubation complications (Potential Hazards)
- Dental damage
- Soft tissue/mechanical injury
- Laryngospasm
- Bronchospasm
- Vomiting/Aspiration
- Hypoxemia/Hypercarbia
- SNS stimulation
- Esophageal/Endobronchial intubation
- ALSO SORE THROAT
MAC Case (describe set up and what it is)
=Monitored Anesthesia care
- Complete Airway Setup Ready to go
- Nasal Cannula- EVERYONE GETS O2
- Spontaneously Breathing Patient
- Nasal airway if snoring (partially obstructed breathing)
How much FiO2 delivered via Nasal Canula (from 1-4L)
1L
2L
3L
4L
When would you use General Anesthesia (MASK CARE)
- Difficult airway not present
- Surgeon does not need access to head/neck (BMT-ok)
- No airway bleeding/secretions
- Case of short duration
- No table position changes- head available…
- Obstruction easily relieved with oral nasal airway/ chin lift
- Patient will spontaneously breathe-no neuromuscular blocker used
When would you use General Anesthesia (LMA CASE)
-Difficult airway not present ◦ Surgeon does not need access to head/neck (?) ◦ No airway bleeding/secretions ◦ Case of short duration ◦ More reliable patent airway than mask ◦ Want hands free
When would you use General Anesthesia (ETT)
◦ Airway compromise
◦ Airway inaccessible
◦ Long surgical time
◦ Alternate surgical positions
◦ Surgery of head, neck, check, or abdomen
◦ Need for controlled ventilation and/or PPV
◦ Inability to maintain airway with mask/LMA
◦ Aspiration risk
◦ Airway/ lung disease
Induction of Anesthesia: STEP 1 is..?
PRE-OXYGENTATION
What is the goal of Pre-Oxygenation?
Increase O2 concentration in functional residual capacity (FRC) by “washing out” nitrogen (79% in RA) in the FRC with oxygen FRC volume of air left in the lung at end of passive expiration
Describe 2 Different Pre-oxygenation methods
1: 3-5 minutes of “tight” mask fit during normal
tidal breathing with100% FiO2 at> 6L/min flow
= 10 minutes of safe apnea time
#2: 4 vital capacity breaths within 30 seconds with 100% FiO2 at >6L/min= 5 minutes of safe apnea time
What is a Laryngospasm?
Severe, sudden, sustained contraction of the glottic
opening (vocal cords) in response to a stimulus (blood,
secretions, light anesthesia) characterized by complete
airway obstruction with retractions
Describe Treatment of Laryngospasm…
◦ Jaw-Lift Maneuver and placement of mask
◦ Administration of oxygen with continuous Positive Pressure
- Strong intermittent pressure applied manually to a bag full of oxygen can force gas effectively through the upper airway and adducted cords.
Immediate removal of the offending stimulus*****
◦ Small dose of short acting Muscle Relaxant Succinylcholine 20-40 mg IV
