Download PHD Resident Airway Lecture

PHD Resident
Airway Lecture
Alan I. Frankfurt, MD
Alan Frankfurt, M.D.;
Gary Weinstein, M.D.
Why Train?


“…my life flashed before my eyes.”
 Meaning?
 Initial response to any stressful/life threatening
experience…
 Mental rolodex scanning
 “Have I ever been in or seen a situation like this before?”
 What worked then?”
 What did not work?
Why train?
 Populating your mental rolodex
 Making the unfamiliar, familiar in a controlled environment.
Training: USAF Experience
 USAF
Red Flag Training Exercise
 90%
of all fighter pilots who died in combat, did
so in their first 10 missions.
 Learning curve: First ten missions.
 Flying those first ten missions in a training
environment.
 Red Flag Training Exercise.
Airway Class Objective

Use this airway training as your own Red
Flag Exercise
 Training
Lecture
 Hands on lab
 Visualization

Airway Topics
Relevant airway anatomy
 Innervation of the airway
 Anesthesia of the airway
 PU<92% Concept
 Airway examination

6
D’s
Airway Definitions and Concepts

Jim Rich, CRNA
 Critical airway event: ability to rescue the airway.
 CICMV
 Intubation difficulty
 Definition: difficult airway
 SPO2<92%
 100% Oxygen
 PPV
 Crash airway: early recognition for patient salvage.
 PU<92
 IRS
 Intubation
 Rescue breathing
 Surgical airway
 Airway Evaluation: 6 D’s
 Difficulty airway options
 Intubation rescue options
 Law of insanity
 AB4C’S
Overview of Upper Airway Anatomy:
Structure and Function
Nares: Nasal Turbinates



Turbinate bones
 Superior
 Inferior
 Middle
Function
 10,000 L of ambient air pass
through the nasal airway per
day and
 1 L of moisture is added to the
air during this process.
Inferior turbinate
 Highly vascular membrane
 Vasoconstriction prior to
instrumentation
 Nasotracheal tube
 Nasopharyngeal airway
Pharynx

Location
 The
pharynx situated
between the nose and
larynx.

3 Divisions
 Nasopharynx
 Oropharynx
 Hypopharynx
(Laryngopharynx)
The Pharyngeal Anatomic Divisions

Nasopharynx



Oropharynx



Termination of the
turbinates and nasal
septum
Soft palate.
Soft palate
Hyoid bone.
Hypopharynx


Hyoid bone
First tracheal ring

AKA Laryngopharynx
Larynx





Base of the tongue (hyoid bone) -> first ring of
the trachea.
Opposite C3-C6
Function
 Watchdog of the airway
 Swallowing
 Organ of phonation
Bones
 Hyoid
Cartilages
 Epiglottis
 Thyroid
 Cricoid
Laryngeal Anatomy
Cricoid Cartilage



Anatomic lower limit of
the larynx.
Only complete
cartilaginous ring in the
upper airway.
Attaches to the thyroid
cartilage by the
cricothyroid membrane.



Laryngotracheal
anesthesia
Surgical airway
Identification in the
patient with poor
anatomic landmarks.
Cricothyroid artery

The superior thyroid
artery


First anterior branch of the
external carotid artery.
The cricothyroid artery


Branch of the superior
thyroid artery
Runs in the upper portion
of the cricothyroid
membrane.


Surgical airway
Tracheal hook placement
Airway Innervation: 5-9-10
Innervation of the Nasal Passage
and Nasopharynx: CN 5

Anterior 1/3 of the
nares.
 Anterior
ethmoidal
nerve

Posterior 2/3 of the
nares.
 Greater
and Lesser
Palatine nerve
Anesthesia for the Mouth and
Oropharynx: CN 9

Anatomy
 Glossopharyngeal
nerve (CN9)
Anesthesia for the Mouth and
Oropharynx: CN 9





Poster 1/3 tongue,
 Gag reflex
Vallecula,
Anterior surface of the
epiglottis (lingual branch),
Posterior and lateral walls
of the pharynx
(pharyngeal branch), and
Tonsillar pillars (tonsillar
branch).
Laryngeal Innervation: CN 10

CN X (Vagus)

Superior laryngeal nerve
 Internal laryngeal
nerve.
 Posterior epiglottis
to vocal cords.
 Penetrates at the
thyrohyoid
membrane.
 External laryngeal
nerve.
 Cricothyroid muscle
Innervation of Trachea and
Vocal Cords

Recurrent Laryngeal
Nerve
 Sensory
innervation of
the tracheobroncheal
tree up to and
including the vocal
cords.
 Intrinsic laryngeal
musculature except
cricothyroid muscle.
Airway Anesthesia


Airway manipulations issue without adequate anesthesia.
 Patient comfort
 Hemodynamic response
 Valsalva
Airway anesthesia options
 “Spray and Pray”: Topicalization of the airway with local
anesthesia
 Entire airway may be anesthetized using topical anesthesia
 Nerve block
 ? Glossophyngeal nerve
 Superior laryngeal nerve
 “Transtracheal nerve block”
Airway Local Anesthesia Drug
Absorption

Topical anesthetic absorption
 Alveoli>Tracheobroncheal
tree>Pharynx
Airway Anesthesia Medications

Cocaine




4% and 10% solutions
3 mg/kg (200 mg maximum dose)
5cc’s in a 70kg person.
Benzocaine


Rapid onset and short duration (10 minutes)
Cetacaine

Methemoglobinemia




Bezocaine, Tetracaine
Cyanosis, fatigue, weakness, headaches, dizziness and tachycardia
Massimo pulse oximeter
Lidocaine

1%, 2% and 4% solutions

Rare to see toxic reactions within the context of airway anesthesia.

4% lidocaine/Afrin mixture

Lidocaine 5% ointment
Lidocaine 2% jelly

Viscous lidocaine.

Tetracaine




Loaded in a syringe
Swish and swallow
Toxicity 100mg (40mg)
Goal of Airway Anesthesia
Airway Preparation for Awake
Airway Manipulation



First: Never sacrifice patient safety for patient comfort.
What are the systemic effects of inadequate airway anesthesia?
 Coughing, straining, valsalva
 Hypertension and Tachycardia
 Myocardial oxygen consumption
 Increased ICP
 Increased IOP
How to prepare for success prior to anesthetizing the airway.
 Maintain the ability to communicate with the patient.
 Dry the airway.
 Maximize effectiveness of the LA applied to the airway.
 Dilution of LA concentration by oral secretions
 Decreases LA effectiveness
 Comfortable patient is a cooperative patient:
 Sedation/analgesia/anesthesia
 Intravenous medications
 Transmembrane medication administration
Patient Preparation for Anesthesia
of the Airway

Antisialogogues (Drying Agents)



Vasoconstrictor



Robinal 0.2-0.4 mg IV
Atropine 0.5-1.0 mg IV
Afrin spray
Phenylephrine 1% spray
Anxiolytics and Analgesia

Versed


Fentanyl


Naloxone
Monitors


Flumazenil
Pulse Oximetry
Supplemental oxygen
Key Airway Anesthesia Principles:
Timing, Positioning and Lubrication



Timing
 Give your preparation drugs time to work.
 Anticholinergic
 Vasoconstriction agents
Positioning
 Position yourself to succeed.
 Go slow
 Monitor the patient
 Masimo pulse oximetry
 Don’t burn any airway bridges
 Reversible agents
Lubrication
 The entire airway can be anesthetized topically with generous
amounts of anesthetic jelly and ointment.
Recurrent Laryngeal Nerve Block:
AKA Transtracheal Block

Indications






Anesthesia for the
laryngotracheal mucosa.
Awake intubation,
Retrograde intubation,
Cricothyrotomy (surgical or
percutaneous),
Abolishment of gag reflex
or hemodynamic response
associated with intubation.
Medications


4% Lidocaine
1-2% Lidocaine
Recurrent Laryngeal Nerve Block:
AKA Transtracheal Block

Patient positioning
 Supine

in the “sniffing” position
Technique
 Cricothyroid membrane identification.
 Local anesthesia skin wheal: Conscious
verse
Unconscious Patient

2-3cc of 4% Lidocaine drawn into a 5cc syringe

20G Angiocath needle.
 Identification of the airway
 Loss of resistance
 Air bubbles signals entry into the larynx.
How I Do It:








Robinal
Afrin/Afrin and 4% Lidocaine
cocktail.
 Nasal manipulation.
Sedation +/Nebulized 4% Lidocaine 2-3cc
 Prior to the application of gels
or ointments.
4% Lidocaine in a syringe dribbled
down the nares.
(Viscous Lidocaine swish and
swallow).
Oral airway/Nasal trumpet with 5%
Lidocaine gel.
 CN9 gag reflex: posterior
tongue.
Transtracheal block with 4%
Lidocaine with 22G-25G needle or
20 G Angiocath.
 Above and below vocal cord
anesthesia.
PU-92 Concept
Crash Airway
Crash Airway Concept: Walls, R.



Teaching Goal: To identify patients in extremis.
Patients who are going to die unless you intervene
quickly and decisively.
Who are these patients?

Altered mental status with airway compromise.





Lethal combination: M/M increased 50-75%
Unconscious
Apneic or having agonal respirations.
Arrested or near death.
Anticipated to be unresponsive and tolerant to laryngoscopy.
Getting Your Arms Around The
Crash Airway: PU-92



Crash airway
 Meant to convey an unmistakable sense of urgency.
 Circling the drain!
From conceptual idea to clinical action.
 PU-92 concept
PU-92:
 Reflects the lethal combination of a cerebral insult (ischemic or
traumatic) and hypoxia.
 Critical nature of early airway support in the face of brain
injury.
 Airway compromise in a patient with compromised
cerebral circulation may DOUBLE mortality.
 Provides a quick and reliable tool to recognize these patients
early and intervene.
PU-92 Parameters
Level of consciousness
 SpO2 level

PU-92 Parameters:
LOC and SpO2

Level of consciousness using the AVPU system



Alert, Voice response, Pain response only or Unresponsive
McKay et al:
 P or U response corresponds to a GCS<9
 GCS<9 immediate indication for intubation
Patients SpO2 level

SpO2<92%, despite:

PPV
 manual airway opening techniques
 100% oxygen ( if available).
If SpO2 unavailable, use a RR <10 or > 30/breathes per minute.
Use of SpO2 in the field environment.
 Masimo
 Movement algorithm
 Low perfusion algorithm
 Co and MetHg



Maximum airway efforts utilizing:
PU<92: Now What?
The Crash Airway Response

Patients require immediate improvement in Ventilation and Oxygenation
 Treatment options: IRS
 Intubation
 Rescue Ventilation
 Surgical airway
 Treatment options are decided upon after an Airway Evaluation
 Airway Evaluation reveals:
 No difficulty anticipated
 One attempt at direct laryngoscopy and Intubation (I).
 Failed intubation fall back to Rescue Ventilation (R)
 Class 2a agent
 Surgical airway (S)
 Difficulty anticipated
 Rescue Ventilation
 Surgical airway
Rescue Ventilation


Positive Pressure Ventilation with Class 2a adjunctive airway device.
 Class 2a: therapeutic option for which the weight of evidence is in favor
of its usefulness and efficacy.
 ETC: Esophageal-tracheal Combitube
 LMA
 (King LT)
 Class 2a devices are supraglottic devices which do not address
obstruction of the airway at the glottic or subglottic level.
 Endotracheal tube
 Cricothyrotomy
Airway literature reveals that rescue ventilation is often effective in providing
ventilation and oxygenation in the following conditions
 CMVCI
 Failed intubation
ECT: Esophageal Combitube Tube
ECT: Esophageal Combitube Tube
ECT: Esophageal Combitube Tube
LMA
King LT
Summary: Crash Airway



Confirm a crash airway exist:
 Patient in extremis.
 PU-92.
Call for help.
Maximize airway support





Manual maneuvers
Airway devices: OA and NT
PPV with 100% O2 as available
Identify possible difficulty airway
Pay the “IRS”
 Intubation attempt
 Only if airway appears easy to intubate
 Airway evaluation
 6 D’s
 Rescue ventilation
 If intubation fails or airway appears difficult
 SpO2>92
 Yes-monitor airway and reassess need for definitive airway
 No->
 Surgical airway
Airway Evaluation
6-D Method of Airway
Assessment
6-D Method of Airway Assessment
6-D method of airway assessment is
meant to assist health care providers in
remembering the six signs that can be
associated with a difficult intubation.
 Each sign begins with a D.
 The potential for airway difficulty is
generally proportional to the number of
signs observed.

6-D Method of Airway Assessment
1. Disproportion.
 2. Distortion.
 3. Decreased thyromental distance (3).
 4. Decreased interincisor gap (2).
 5. Decreased range of motion in any or all
joints of the airway (1).
 6. Dental overbite.

6-D Method of Airway Assessment

Disproportion


Size of tongue in relation to the oropharyngeal size.
 Obstructed laryngoscopic view of airway.
 Airway trauma (blunt or penetrating) with resultant swelling.
 Patient’s anatomy
 Assessment
 Mallampati Classification
Predicting airway disproportion problems:
 Mallampati class 4 (3?)
 Swelling or protruding tongue
 Blunt or penetrating injury
 Receding mandible
Mallampati Airway Classification
System




Class 1:
 soft palate, uvula, anterior and posterior pillars are visible.
Class 2:
 soft palate and uvula are visible
Class 3:
 only soft palate and base of uvula visible.
Class 4:
 hard palate visible, but not the soft palate.
6-D Method of Airway Assessment


Distortion
Etiology:


Neck mass, neck hematoma, neck abscess, previous surgery or
trauma.
Predicting airway distortion problems:





Voice change
Subcutaneous emphysema
Laryngeal immobility
Non palpable thyroid and/or cricoid cartilage.
Neck asymmetry


Tracheal deviation
Subcutaneous emphysema
6-D Method of Airway Assessment

Decreased thyromental distance


Reflects an anterior larynx and decreased sub-mandibular
space.
Problem:


Unable to displace the tongue into the submandibular space, out of
the view of the laryngoscopist.
Predicting airway difficult resulting from decreased
thyromental distance:

Thyromental distance <7 cm (<3 FB)


Measured from the superior aspect of thyroid cartilage to the tip of
the chin.
Underdeveloped mandible
6-D Method of Airway Assessment

Decreased interincisor gap
Reduced mouth opening
 Reduced ability of the oral cavity to accommodate airway
instrumentation.
Predicting airway difficulty secondary to decreased incisor gap
distance:
 Distance between the upper and lower incisors is <4 cm ( 2 FB )
 Mandibular condyle fracture.
 Rigid cervical collar.
 TMJ dysfunction


6-D Method of Airway Assessment

Decreased range of motion in any or all of the
joints of the airway.


Atlanto-occipital joint, cervical spine and TMJ.
 Sniffing position.
Predicting airway difficulty secondary to decreased ROM of
joints involved in assuming the sniffing position:
 Head extension < 35 degrees
 Neck flexion < 35 degrees
 Short, thick neck
 Cervical spine collar or C spine immobilization
6-D Method of Airway Assessment

Dental overbite
 Large
angled teeth disrupt the alignment of
the airway axes and possibly result in
decreased interincisor opening.

Predicting airway difficulty secondary to
dental overbite:
 Protruding
maxillary incisors.
Treatment of Airway Loss: Operator
Skill and Equipment Requirements.

Causes of Airway Obstruction:
LIFT




L-Level of consciousness
 Trauma or Medications.
 Loss of muscle tone
 Jaw lift
 Nasal trumpet
I-Inflammation
 Burns
 Early intervention
 Advanced airway
techniques
 Anaphylaxis
F-Foreign body
 Blood clots, teeth, bone, food…
 Finger sweep, positioning
T-Trauma

If it was pushed in…pull it out.

Treatment of Airway Obstruction:
AIR



A-Assess for airway obstruction

Recognition

Signs and symptoms
 Dysphonia, noisy breathing,
RR<8 or >30, use of accessory
muscles.
I-Improve the airway

Positioning
 Position of comfort
 Recovery position
 Cervical spine precautions.

Mechanical
 Jaw thrust,
 Chin lift

Nasal trumpet(s)
R-Remove any debris

Finger sweep
Indications for Tracheal Intubation












Airway protection and risk for aspiration.
Need for a definitive airway.
Patient will be going to OR and has an unstable airway.
Respiratory failure/arrest and in need of mechanical ventilation
PEEP administration
GCS<9 or on AVPU scale a “P” or “U”
ACLS drug administration
Pulmonary toilet
Hypoxemia refractory to oxygen therapy
Uncontrolled seizure activity
Depressed LOC in a trauma patient
Combative patient with a compromised airway.
Emergency Indications for
Intubation

Can’t protect airway
 Gag reflex absent in 37% population
 Ability to swallow and manage secretions

Can’t maintain Ventilation/Oxygenation
 Inability to maintain SpO2>92% on oxygen,
 PaCO2>55 or 10 torr above baseline.
 RR <8 or >30/ minute

Expected decline in clinical status.
 Deterioration/Impending
 Transport
compromise
Contraindication to RSI

Evaluation of the patient’s airway reveals that laryngoscopy and intubation
would not be successful


Unfamiliarity with the technique


Do what you do all the time.
Lack of any rescue ventilation options


6 D’s
Plan A, B, C.
Other safer options


Awake intubation under topical and nerve block anesthesia
Cricothyrotomy under local anesthesia



Local infiltration
Transtracheal block
Don’t burn an airway bridge.

A lousy airway is better than no airway.
Direct Laryngoscopy Checklist











Variety of laryngoscopy blades
Variety of Endotracheal tube (ETT) sizes
Stylett the ETT
Boogie
Test balloon on ETT
Class 2a rescue ventilation device
Adequate muscle relaxation if indicated
Head position
Suction
Test IV patency
Pre-treatment










Oxygen
Vagolytic
Non particulate antacid
RSI indicated?
Assistant present as available
Look for the epiglottis first
Don’t shotgun the laryngoscope
Control the tongue
Don’t lever the blade.
Intubation confirmation device
Techniques to Rescue
a Difficult Intubation
Avoid the Law of Insanity
Law of Insanity
Doing the same thing over
and over again while
expecting a different result.
Techniques to Rescue a Difficult
Intubation
Access
 Visualization
 Passage of the ETT

Techniques to Rescue a Difficult
Intubation: Law of Insanity

AB4C’S
 Axis
 Boogie
 BURP
 Blade:
size and type
 Block
 Cricoid
pressure: let up
 Stylet/Smaller ETT
Techniques to Rescue a Difficult
Intubation

Sniffing Position
 Head
extension
 Neck flexion

Onto the shoulders
 20-30
degree angle
Aligning Axes of Upper Airway
A
Mouth
A
B
B
Pharynx
C
C
Trachea
Extend-the-head-on-neck (“look up”): aligns axis A relative to B
Flex-the-neck-on-shoulders (“look down”): aligns axis B relative to C
External Laryngeal manipulation
(ELM): BURP

BURP


Laryngoscopist
hand placed on
top of assistant’s
hand.
Backward,
Upward,
Rearward
Pressure.

Thyroid
cartilage
Gum Elastic Bougie
Gum Elastic Bougie





Most beneficial with a Grade III larygoscopic view.
Works synergistic with other airway maneuvers
 ELM: BURP airway manipulation
 Jaw thrust/chin lift.
Indicators of successful tracheal placement of the bougie
 Tracheal clicking
 Hold up
Leave the laryngoscope in place during ETT insertion with the bougie in
place.
Rotate the ETT counter clockwise 90 degree to prevent the tip of the ETT
from hanging up on laryngeal structures during passage.
BURP Maneuver




Difficult intubation rescue option
 Improve visualization of the larynx by at least one grade.
Knill RL; Can J Anesth 1993;40:279-82
BURP maneuver results in displacement of the larynx in three
specific directions to place the vocal cords in view of the operator:
 Backward-Thyroid cartilage displacement dorsally (backward)
as to abut the larynx against the bodies of the cervical vertebrae.
 Upward-Thyroid cartilage is moved cephlad about 2 cm until mild
resistance is met.
 Rightward-laterally to the right approximately 0.5-2.0 cm.
 Pressure
Employing the BURP maneuver, the assistant moves the larynx
until mild resistance is met.
BURP Maneuver
Mechanism of Action

As a result of the BURP maneuvers, the glottis is moved
directly into the line of vision. Let’s examine why this is
true:

The laryngoscope enters the oral cavity from the right and
displaces the tongue toward the left.




Tongue attached to larynx.
Hence the larynx is moved leftward as well.
Resulting visual pathway is somewhat to the right side of the oral
cavity midline.
BURP maneuver may improve visualization of the glottis by
moving the larynx more into the line of vision.
Effect of BURP on Visualization
Grade
Initial
After
Inspection BURP
Grade 1
0
231
Grade 2
181
38
Grade 3
80
4
Grade 4
12
0
Surgical Airway
Cricothyrotomy
Rapid Access to the Airway or
Not.
Indications for Surgical Airway

Clinical
 Mid

face trauma
Blunt vs. Penetrating
 Airway
obstruction above the level of the
cricoid cartilage.
 Anaphylaxis/Anaphylactoid reaction
 Burn
 Failed intubation and failed rescue ventilation
Cricothyrotomy:
Rapid 4 Step Technique

Instruments: Rapid 4
Step Technique
 Scalpel
with a no.20
blade, tracheal hook,
no. 6 Shiley
tracheostomy tube.

Instruments: Std
Technique
 Scalpel
with no.11
blade, Trousseau
dilator, hemostats,
tracheal hook, no. 6
Shiley tracheostomy
tube.
Cricothyrotomy:
Standard Technique

Steps
 Identification of the cricoid membrane
 Palpation

Dissection
4 cm vertical skin incision over the cricoid membrane.
Short horizontal stab wound over the lower portion of the cricoid
membrane.
 Never remove scalpel blade until tracheal in place.
Stabilization of the larynx with a tracheal hook at the inferior
aspect of the thyroid cartilage.
Dilation of the ostomy with a curved hemostat.
Placement of the Shiley tube/Endotracheal tube.






Sternal notch
Cricothyrotomy:
Rapid 4 Step Technique

Steps
 Identification
of the cricothyroid membrane by
palpation.
 Horizontal stab wound through the skin and
cricothyroid membrane with the scalpel.

Non-palpable anatomy: skin incision
 Stabilization
of the larynx with the tracheal hook at the
inferior aspect of the ostomy (on the cricoid cartilage),
providing caudal traction.
 Placement of the Shiley tube in the trachea.
Cricothyrotomy:
Modified Technique

Identification of the cricoid cartilage.


Easy
Hard



Anesthesia?



Local infiltration
Transtracheal block
2-4 cm vertical incision overlying the cricoid membrane.




Non palpable and non visualized
Sternal notch and work your way upward.
Not a cosmetic procedure.
Use the entire incision
Define your anatomy
No. 20 blade attached to a scalpel for cricoid membrane puncture.

Puncture made at the superior aspect of the cricoid cartilage.
Cricothyrotomy:
Modified Technique





Tracheal hook applied to the superior surface of the cricoid cartilage.
The cricoid cartilage is delivered out of the wound.
 Stabilizes the larynx.
 Prevents blood from pooling in the wound.
 Not working in a deep hole.
Kelly clamp used to dilate the ostomy.
#5-6 ETT/#6 Shiley placed in the ostomy
 Bougie
Confirmation of tracheal intubation
 CO2 detection
 Capnography
 Colorimetric
 SIB (Self inflating bulb)
Questions?