Leo- Eval of Airway Flashcards
(107 cards)
1
Q
What are the 3 unpaired larynx cartilages?
A
Cricoid
Thyroid
Epiglottis
2
Q
What are the 3 paired larynx cartilages?
A
Arytenoids
Cuneiforms
Corniculate
3
Q
What is the function of the PosteriorCricoArytenoids muscle?
A
Pull Cords apart (PCA) ***
4
Q
Cricothyroid
A
Lengthen and stretch
5
Q
VOCALIS (vocal ligament)
A
part of muscle that help with voice
6
Q
Larynx all nerves come from
A
Vagus
7
Q
***Most of motor function comes from the
A
Recurrent LARYNGEAL nerve
8
Q
➢ Difficult mask ventilation
A
“Not possible for the unassisted anesthesiologist to prevent or reverse signs of inadequate ventilation during positive pressure mask ventilation
9
Q
➢Difficult intubation
A
The proper insertion of an endotracheal tube using conventional laryngoscopy requires more than 3 attempts, or greater than 10 minutes”
10
Q
➢Failed airway is defined as
A
⚫ 3 failed attempts at orotracheal intubation by a skilled provider
⚫ Failure to maintain acceptable saturations (> 90%) in otherwise normal individuals
11
Q
ASA Closed Claims Database: single most important factor leading to fail airway
A
“Failure to evaluate the airway and predict difficulty is the single most important factor leading to a failed airway”
12
Q
Incidence of Difficult Intubation by Rigid Laryngoscopy
⚫ Failed intubation 1 in 280
A
➢ Parturient 2.7%
13
Q
Parturient and intubation
A
Almost 10x greater than in the nonparturient patient
14
Q
➢ Major cause of injury in anesthetic practice
A
➢ Inadequate ventilation—largest class of adverse events
15
Q
_____is especially important in patients at high risk for aspiration
A
Anticipation
16
Q
Factors preventing a snug mask fit,
A
interfering with positioning of head and neck, limited opening of mouth, and narrow or distorted airway
17
Q
Difficult Intubation Predictors:➢ External anatomic features
A
- ↓ Head/neck movement (atlanto-occipital joint)
- Jaw movement (temporo-mandibular joint), mouth opening, and subluxation of the mandible
- Receding mandible
- Protruding maxillary incisors
- Obesity
18
Q
More Predictors o difficult airway
A
Thyromental distance <6cm or 3 fingerbreaths.
• Sternomental distance
• Visualization of the oropharyngeal structures
• Anterior tilt of the larynx
• Radiographic assessment
19
Q
Mouth opening (distance between incisors) limited to
A
3.5 cm or less will contribute to difficult intubation
20
Q
Mouth opening is limited by
A
Limited by: ⚫ TMJ dysfunction ⚫ Congenital or surgical fusion of the joints/ vertebrae ⚫ Trauma ⚫ Tissue contracture around the mouth ⚫ Trismus (lock jaw)
21
Q
Protruding maxillary incisors can interfere with
A
laryngoscope placement and ETT passage
22
Q
Mouth opened maximally normal
A
normal opening 5-6cm
23
Q
➢ Class II–
A
base of tongue obscures tonsillar pillars, posterior pharyngeal wall visible below soft palate, uvula
24
Q
➢ Class III–
A
only soft palate visualized (7.58 x greater chance of difficult intubation than class I)
25
➢ Class IV--
essentially nothing visualized, not even soft palate (11.2x greater chance of difficult intubation than class I)
26
Don’t Forget . . .
➢ Overbite
➢ Mobility of and ability to displace mandible
– can patient push jaw to place lower teeth
past the top teeth
27
⚫ May not be able to pull mandible forward far
| enough to see larynx - TMJ
➢ Tongue Size
➢ Loose, chipped, or missing teeth, or dental
work
28
Micrognatia
No room to displace the tongue and epiglottis forward
29
➢ Anterior airway associated wtih ______
Micrognatia ; with the laryngoscope, the structures will be anterior to your field of view
30
Neck ➢ Limited Mobility -
Neck touch chin to chest, both shoulders, and extend back (normal 55 degrees) Harder to push tongue and epiglottis forward
31
➢ Neck circumference
>27 inches is suggestive of difficult management
32
Neck: With trachea check
➢ Trachea mobility and alignment
33
➢ TM Less than
3 fingerbreadths is considered a receding mandible and may contribute to difficulty with intubation
34
➢ Rigid laryngoscopy may be impossible if
<6cm
35
➢ TM Measured with the
head fully extended,
between the bony part of the mentum of
the mandible and the thyroid notch
36
➢ TM Measured with the
head fully extended, between the bony part of the mentum of the mandible and the thyroid notch
37
Atlanto-occipital Mobility
Alignment of the oral, pharyngeal, and laryngeal axis required for visualization of the glottis during rigid laryngoscopy
38
Head has to be above the
Breast
39
What is responsible for the sensory and motor innervation of the larynx?
The vagus nerve (cranial nerve X), via the superior and recurrent laryngeal nerve, is
40
Has the highest density of touch receptors
The posterior half of the vocal cords
41
During bedside evaluation of Atlanto occipital mobility?
Bedside evaluation: have the patient sit straight and extend their head while maintaining a neutral cervical spine
42
With Atlanto occipital mobility ↓ degree of head extension indicate→
↑ possibility
| for difficult intubation
43
Axis alignment
Elevation of the head about 10 cm with pads below to occiput with the shoulders remaining on the table aligns the laryngeal and pharyngeal axis
44
Head extension at the atlanto-occipital joint
| serves to
create the shortest distance and most nearly straight line from the incisor teeth to glottic opening
45
Difficult bag-mask-ventilation: MOANS
```
➢ M: Mask seal
➢ O: Obese
➢ A: Aged
➢ N: No teeth
➢ S: Snores or stif
```
46
Difficult laryngoscopy and intubation: LEMON
```
L: Look externally
➢ E: Evaluate 3-3 (3 fingers between teeth, 3
fingers chin-neck to thyroid notch)
➢ M: Mallampati class
➢ O: Obstruction
➢ N: Neck mobility
```
47
Radiography: Not routine but To confirm vertebral damage and reveal degree of airway compression
⚫ Lateral C spine
⚫ MRI
⚫ CT
48
***Predictors*** of a Difficult Airway
```
➢ High Mallampati Classification
➢ Small mouth opening
➢ Prominent Incisors
➢ Thyromental Distance <6 cm
➢ Decreased neck extension
➢ Neck Circumference
```
49
Predictors of Difficult FACE MASK VENTILATION
| ABBSMLL
```
➢ Age >55 y.o.
➢ BMI >26-30 kg/m2
➢ Beard
➢ Snoring
➢ Lack of teeth
➢ Mallampati III or IV
➢ Limited mandibular protrusion
```
50
Single most important predictor for both Difficult mask
| ventilation and difficult intubation
Limited mandibular protrusion
51
Predictors of Impossible Face Mask Ventilation
```
➢ Male
➢ Beard
➢ Obstructive Sleep Apnea
➢ Mallampatie III or IV
➢ Neck radiation changes
```
52
Many of the airway tests such as Mallampati and thyromental distance have limitations
Interobserver variability, low to modest sensitivity, inability to assess for base of tongue pathology
53
Categories of Difficult Airway
➢ Known or expected difficult airway
➢ Probable difficult airway
➢ Unexpected difficult airway
54
Mouth opening & proper position of the
| Head & Neck adversely affected by:
➢ Tissues of head/neck, oral cavity, pharynx, & larynx fixed by tumor, surgical scars, or radiation fibrosis
➢ Supra-epiglottic mass may limit mobility of Epiglottis → complete airway obstruction after induction
55
➢ Rheumatoid arthritis→ pathologic changes
| ➢ May involve any joint
⚫ Cervical spine
⚫ Temporomandibular joint
⚫ Cricoarytenoid joint
56
➢ may indicate laryngeal involvement
Change in voice, dysphasia, dysarthria, stridor,
| or sense of fullness in oropharynx
57
Progressive cervical spondylosis (degeneration) can lead to
severe flexion deformity
58
Should be the technique of choice if there is any reason to believe that maintaining a patent airway after induction of
anesthesia may be difficult
Awake intubation
59
______________ in patients with an unstable neck should be done with extreme caution.
➢ Avoid movement that can cause spinal
cord compression and damage
Tracheal intubation
60
Awake fiberoptic intubation can be performed without
| ➢ Any head and neck stabilizing device can be left in place to prevent movement of c-spin
atlanto-occipital extension
61
Predictors of difficult video laryngoscopy
```
Scarring
➢ Radiation
➢ Masses
➢ Large neck circumference
➢ TMD < 6 cm
➢ Limited neck mobility
➢ Operator experience
```
62
➢ Airway assessment should be performed with
| the patien
in a sitting position as well as supine.
63
➢ Respiratory function and airway patency can be
| greatly changed with
position changes.
64
What may interfere with spontaneous respirations?
➢ Chest compliance and vital capacity change
65
➢ Even with local or regional anesthesia, work of
| breathing may be
Excessive and require ventilatory support
66
For mobid Obesity create an Create an angle where the
____
Why? •
head and neck are above the thorax, so gravity will pull the weight away from airway
helps view and gives room for laryngoscope handle
67
The higher incidence of (3 conditions) found in obese
| patients, place these patients at a higher risk for aspiration of gastric contents
hiatal hernia
low gastric pH ( < 2.5),
low FRC
68
For obese patient, to minimize the risk of
| aspiration, what is performed?
a RSI is commonly performed
69
Safe and logical approach for morbid obese patients?
Securing the airway in morbidly obese patients before induction of anesthesia
70
2 studies show no correlation between
obesity and difficult intubation
71
Morbid Obesity Weight distribution and consideration
Abdomen & hip area less important than if weight is
| also in upper body;
72
Fat in upper body lead to Cervical spine fat pads interfere with
laryngoscopy
73
Rapid desaturation during apnea 2o to
↓ FRC limits time for intubation
74
➢ Life threatening infection
Epiglottitis
75
Epiglottis is what kind of infection?
Bacterial
| ➢ Lasts 2-4 days
76
Epiglottis onset and progression
➢ Rapid onset and progression→ urgent dx and tx
77
4 Ds of Epiglottis
Dysphagia, dysphonia, dyspnea, drooling
78
S & S of airway injury
Subcutaneous emphysema
Hoarseness
Stridor,
Tracheal deviation
79
Trauma Patient
| Examine for
➢ Examine for cervical spine injuries
⚫ Cervical collar & axial traction during intubation
⚫ Limited range of motion
80
Congenital Syndromes most often accompanied by aberrations of the upper airway (4)
⚫ Crouzon’s
⚫ Goldenhar’s
⚫ Pierre Robin’s
⚫ Treacher Collins
81
Congenital syndromes: These children may also have a shortened trachea and should have
ETT positioned fiberoptically
82
Crucial to assess
mouth size and opening, size of tongue, and neck movement, as well as feeling the neck under the mandible
83
Intrathoracic Lesions
| ➢ IT lesions can compromise the airway through
compression of the tracheobronchial tree or by invasion of the trachea or bronchi
84
➢ Anterior mediastinal tumors can completely
block the airway when a patient is placed in a
| supine position
85
➢ If flow-volume loop deterioration occurs in the
| supine position,
the patient should not be anesthetized or paralyzed
86
Cormack-Lehane laryngeal grading system
➢ View during direct laryngoscopy
➢ III
III—epiglottis
87
Cormack-Lehane laryngeal grading system
➢ View during direct laryngoscopy
➢ I—
entire glottic opening
88
Cormack-Lehane laryngeal grading system
| ➢ View during direct laryngoscop II—
posterior glottic structures
89
Cormack-Lehane laryngeal grading system
| ➢ View during direct laryngoscopy➢ IV
soft palate only
90
Anteriorly Tilted Larynx
➢ Degree of thyroid cartilage tilt can be
related to
➢
difficulty of laryngeal exposure
| w/ Mac blade
91
Anteriorly Tilted Larynx Reduced exposure
by depression of the thyroid cartilage
92
Anteriorly Tilted Larynx Increased exposure by
cricoid pressure
93
Unexpected Difficult Airway
Hyperplasia of the lingual tonsils, a lingual thyroid nodule/cyst, and an asymptomatic epiglottic cyst can contribute to a failed intubation or ventilation.
94
Anatomical Features Associated with unanticipated Difficult Intubations
```
Anterior larynx (most common)
➢ Abnormal neck anatomy (poor mobility, short)
➢ Decreased mouth opening
```
95
The KEY to successful awake intubation
Topical anesthesia
96
Most conservative approach when difficult airway is
| known or suspected
Awake intubation
97
During awake intubation, Important to use
glycopyrrolate to dry mucous membranes prior to topical LA (at least 20 min before)
98
When deciding on awake vs. asleep airway management:
➢ If difficulty w/ ventilation by both mask &
supraglottic airway device is anticipated.
➢ Consider presence of at least 3 factors
predictive of difficult or impossible to mask
ventilate
99
Preexisting Airways
```
➢ Endotracheal or tracheal
➢ Indication
➢ Date of Placement
➢ Ease of Placement
➢ Size
➢ Presence of cuff
➢ Vent settings
➢ Recent ABG
```
100
Difficult intubation is a
life-threatening situation
➢ Even the most experience provider seeks
help
101
Unexpected failed intubation/ventilation may be
| due to
Supraglottic mass or lingual tonsillar
| hyperplasia
102
Incidence of tracheal stenosis after emergency
| tracheostomy is
high (FO evaluation prior to intubation is suggested)
103
When in doubt, secure airway with the patient
awake and spontaneously breathing
104
are the major airway management problems in
| pediatrics
Infection related and congenital airway compromise
105
➢ In adults, stridor at rest=
serious obstruction w/ cross sectional opening less than 4mm
106
Should always be available
➢ Emergency airway management cart
107
➢ Important for pt w/ difficult airway to get
```
MedicAlert
bracelet (make sure to document on record)
```
