Difficult Airway Flashcards

1
Q

Definition of the difficult airway?

A
  • Difficulty with ventilation by mask or supraglottic airway (SGA)
  • Difficulty with endotracheal intubation
  • Or both
  • ASA definition:
    • ** > 3 attempts w/ DVL (average laryngoscope) for endotracheal intubation
    • ** > 10 minutes for endotracheal intubation
      • major factor in anesthesia morbidity
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2
Q

What is a difficult mask or SGA?

A
  • Inability of an unassisted anesthesia clinician to maintain alveolar oxygen delivery or reverse signs of inadequate ventilation
    • D/t inadequate mask seal, excessive gas leak, or excessive resistance to ingress/egress of gas
    • Visualize by:
      • Inadequate chest rise and fall, absent breath sounds, cyanosis, inadequate oxygen saturations, inadequate spirometric measurements of exhaled gases, or signs of hypoxemia or hypercarbia
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3
Q

Most common predictors of difficult airway in closed claims analysis?

A
  • airway obstruction
  • past h/o difficult intubation
  • Mallampati 3-4
  • limited cervical spine extension
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4
Q

Airway review of nares?

A
  • Primary function is warming and humidification of air
  • Olfaction/speech
  • Roof → formed by the cribriform plate of the ethmoid bone
    • Fragile structure
  • Mucosal lining → very vascular (susceptible to trauma)
    • apply vasoconstrictors to help prevent epistaxis
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5
Q

Airway review of pharynx?

A
  • muscular tube that extends from the base of the skull down to the level of the cricoid cartilage (inferior boarder- C6 vertebral level) and connects the nasal and oral cavities to the larynx and esophagus.
    • Respiratory & digestive fx
    • Becomes continuous w/ esophagus
  • In an awake patient, the pharyngeal musculature helps maintain airway patency.
    • Sedation → Loss of pharyngeal muscle tone
      • Primary cause of airway obstruction
  • Divided into:
    • Nasopharynx
    • oropharynx
    • Hypopharynx (laryngopharynx)
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7
Q

Airway review of larynx?

function?

location?

composition?

A
  • Fx:
    • Phonation- contains VC
    • airway protection- prevent food aspiration into trachea while breathing
  • Located between C3 – C6
  • Complex structure of cartilage, muscle, and ligaments that serves as the inlet to the trachea
    • Superior portion:
      • Epiglottis- attached to hyoid bone (attached to inferior pharynx)
    • Inferior portion: attached to superior trachea
  • 9 cartilages
    • 3 Unpaired
      • Epiglottis
      • Thyroid- “thyroid ring” (only cart to encircle trachea completely)
      • Cricoid
    • 3 Paired – arytenoid, corniculate & cuneiform
  • Cricoid is only complete cartilaginous ring
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8
Q

What provides sensory to the airway?

A
  • Trigeminal (CN 5)
    • Ophthalmic (V1): anterior ethmoid
      • Anterior mucous membranes
    • Maxillary (V2): sphenopalatine
      • Posterior mucous membranes
    • Mandibular (V3): lingual
      • Anterior 2/3rds of the tongue
  • Glossopharyngeal (CN 9)
    • Roof of pharynx, tonsils, and under surface of palate
    • Posterior 1/3rd of tongue
  • Vagus (CN 10)
    • Superior laryngeal nerve (has internal (sensory) and external (motor) branch )
      • Below epiglottis–> VC
      • Internal branch of superior laryngeal: laryngeal mucosa
    • Recurrent laryngeal nerve
      • Below vocal cords
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9
Q

Airway review of trachea?

specifications and measurements?

A
  • Specifications:
    • tubular structure
    • Starts C6 → extends to T5 (carina/bifurcates)
    • Anterior aspect:16-20 C-shaped cartilages (horseshoe)
    • Posterior aspect: Membranous/flat– (good landmark for fiberoptic intubations)
  • Measurement:
    • Length: ~10-16 cm long (avg.)
    • Diameter: tracheal lumen narrows slightly as progresses towards carina
      • M: 22 cm
      • W: 19 cm
    • Distance from tracheal carina to the bifurcation of the left upper and left lower lobe is approximately:
      • M: 5.0 cm
      • W: 4.5 cm
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11
Q

What provides motor innervation to the airway?

A

Trigeminal (CN 5): mandibular branch (V3)

  • Muscles of mastication

Hypoglossal (CN 12)

  • All intrinsic and extrinsic muscles of tongue
    • except palatoglossus muscle (vagus)

Vagus (CN 10)

  • Recurrent laryngeal nerve
    • All intrinsic muscles of the larynx
      • except the cricothyroid muscles
    • Posterior cricoarytenoid muscle
      • sole muscle responsible for abduction of VCs
        • Unilateral RLN injury: hoarseness
          • concern in ACDF and thyroid sx
        • Bilateral RLN injury: partial vs. complete airway obstruction → extreme AW emergency!
  • Superior laryngeal nerve (internal and external branch)
    • External branch: cricothyroid muscle (motor)
      • tenses and adducts VCs
        • Injury: voice quality, generally not dangerous
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12
Q

Components of airway assessment?

A
  • History – anesthesia, medical, surgical
    • Previous AW issues in the past?
    • Head/Neck sx in past?
    • Dental damage?
    • prolonged airway swelling?
  • Physical exam
  • Thorough airway exam
  • Questions r/t the airway
  • Documentation
  • Better to falsely predict a difficult airway and be prepared
  • ***No infallible method to identify a difficult airway
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13
Q

Appropraite assessment of previous intubation history?

A
  • *One of the most predictive factors for difficult intubation is a history of previous difficult airway or intubation.
    • Inquire about previous anesthetics
      • Dental damage?
      • Prolonged/ severe sore throat?
      • Were you advised on intubation techniques for the future?
    • Are anesthesia records available? → LOOK
    • Documents/registry?
  • On the other hand, a history of easy intubations do not rule out the possibility of difficult ventilation or intubation.
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14
Q

What are congenital syndromes associated with difficult airway?

A
  • Pierre-Robin Syndrome (congenital compression/genetic)
    • Micrognathia, macroglossia, cleft soft palate
  • Treacher-Collins Syndrome (genetic – Tcof1)
    • Auricular and ocular defects, malar and mandibular hypoplasia
  • Goldenhar’s Syndrome (Unknown/Branchial arch development)
    • Auricular and ocular defects, malar and mandibular hypoplasia
  • Down’s Syndrome (trisomy 21)
    • Poorly developed or absent bridge of the nose - macroglossia
  • Klippel-Feil Syndrome (GDF3, GDF6, MEOX1)
    • Congenital fusion of a variable number of cervical vertebrae – limited ROM
  • Turner Syndrome
    • Frequent/ complex abnormality affecting women
    • Short neck, maxillary & mandibular hypoplasia
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15
Q

Medical history concerns with airway assessment?

A
  • Airway pathology (tumor)
  • Mediastinal mass- CT/Xray useful
  • Thyroid dx → diff breathing lying flat/swallowing
  • Trauma- C/S
  • Arthritis/ ankylosing spondylitis
  • Obesity
  • OSA
  • Pregnancy
  • Acromegaly
  • Burns
  • Genetic disorders
  • Musculoskeletal deformities
  • Radiation therapy
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16
Q

What are infections that can lead to difficult airway?

A
  • Epiglottitis
    • Potentially life-threatening bacterial infection
    • May lead to emergent airway management
  • Croup
    • Viral mediated inflammation
    • Steeples sign- subglottic tracheal narrowing noted on CXR
    • Laryngeal edema/airway irritability
  • Retropharyngeal abscess
    • Distortion of airway/ mask ventilation and intubation difficult
  • Ludwig’s angina
    • Abscess in floor of the mouth under the tongue
      • Edema/obstruction/distortion of airway/trismus →
      • Video laryngoscopy/fiberoptic intubation optimal!
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17
Q

Other conditions that can lead to difficult airway?

A
  • Head/Neck Radiation
    • Friable tissue, edema, limited ROM/mouth opening
  • Morbid Obesity
    • Short thick neck, redundant tissue, large tongues and apnea likely
  • Acromegaly
    • Macroglossia and hypertrophy of laryngeal/pharyngeal tissue
  • Burns
    • Edema, distortion, fixation of tissue from scars, bronchospasms
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18
Q

What previous surgical history predispose to difficult airways?

Surgeries that can cause postop airway issues?

A
  • Previous Surgical History
    • Tracheostomy or scar
      • Have you been intubated since tracheostomy taken out?
      • May need smaller ETT
    • Neck dissection
    • UPPP
    • Cervical neck fusion → video/fiberoptic tech optimal
  • Post-op Period Emergencies (hematoma)
    • Thyroidectomy
    • Tonsillectomy
    • Neck Dissection (Hematomas postop period)
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19
Q

Physical characteristics to look out for on preop assessment of airway?

A
  • Facial deformities?
  • Neck-size circumference + length
  • Goiter?
  • Mandible-receding?
  • Facial hair?
  • Cervical collar?
  • Trachea midline?
  • Nares-size? Open? Mouth breathing? Flaring?
  • Mouth-lips, tongue, tissues-color, size, condition?
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20
Q

Features of an airway exam?

A
  • Mouth opening
  • Size & mobility tongue
  • Palate- high or arched?
  • Visualization of supraglottic masses/ tonsillar hyperplasia?
  • Size & shape mandible; maxillary overgrowth?
  • TMJ –degree of motion? Dislocations?
  • Ability to advance lower incisors in front of upper?
  • Neck circumference
  • Thyromental distance
  • Mallampati
  • Dentition
    • **Evaluating for the ease of DL, but predicting difficult DL remains, in large part and enigma
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21
Q

How do we assess mouth opening?

A
  • Inter-incisor distance/gap:
    • Measured from upper to lower incisors
      • Normal: > 4.5 cm
      • Abn: < 3 cm (2 finger breaths) (some video need 2 cm for insertion)
        • suggestive for difficult airway
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22
Q

What is the modified mallampati classification system?

A
  • assess relationship b/t tongue size and oropharyngeal cavity
    • Diff mask/vent & diff laryngoscopy:
      • III: visualize base of uvula only
      • IV: soft palate no visible

Tests → POOR predictor ALONE (use together)

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23
Q

What is thyromental distance? Sternomental distance? Purpose?

A

Helps determine how readily the laryngeal and pharyngeal axis aligns

  • Thyromental: Measure from upper edge of thyroid cartilage to chin/jaw with the head fully extended
    • A short thyromental distance = an anterior larynx
      • Normal: 6.5 cm
        • > 7 cm = usually easy intubation
      • Diff Intubation: < 6 cm
  • Sternomental: Upper border of manubrium (sternal notch) to the tip of the mandible w/ head extended
    • Sternomental distance:

Diff Intubation = < 12.5 cm

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25
Q

What is the cormack and lehane classification system?

A
  • A. Class I: full view of the glottis
    • *** Likelihood of difficult intubation Class I: < 1%
  • B. Class IIa: partial view of the glottis
    • *** Likelihood of difficult intubation Class IIa: 4.3-13.4%
  • B. Class IIb: only the posterior glottis is seen or arytenoid cartilages
    • *** Likelihood of difficult intubation Class IIb: 65-67.4%
  • D. Class III: only epiglottis is seen
    • *** Likelihood of difficult intubation Class III: 80-87.5%
  • E. Class IV: Neither glottis nor epiglottis is seen
    • *** Likelihood of difficult intubation Class IV: very likely
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27
Q

What neck circumference is predictive of a difficult airway?

A
  • Predictive diff visualization of glottic opening: 17 in (42 cm)
    • Increase in pretracheal and soft tissue ass w/ DAW
    • Inability to achieve optimal neck extension
    • Fatty tissue around posterior pharyngal/buccal skin folds → diff visualizing of glottic opening
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28
Q

What is the strategy for intubation of the difficult airway?

A
    1. Assessment of four basic problems that may occur alone or in combination:
      * a. difficult ventilation
      * b. difficult intubation
      * c. difficulty with patient cooperation or consent
      * d. difficult tracheostomy
    1. Actively pursue opportunities to deliver supplemental oxygen
    1. Consider feasibility of three basic management choices:
      * a. awake intubation versus intubation after induction of general anesthesia
      * b. use of noninvasive techniques for the initial approach to intubation versus the use of invasive techniques (i.e. , surgical or percutaneous tracheostomy or cricothyrotomy)
      * c. preservation of spontaneous ventilation during intubation attempts versus ablation of spontaneous ventilation during intubation attempts
    1. The identification of a primary or preferred approach to:
      * a. awake intubation
      * b. the patient who can be adequately ventilated but is difficult to intubate
      * c. the life-threatening situation in which the patient cannot be ventilated or intubated
    1. The identification of alternative approaches that can be employed if the primary approach fails or is not feasible
    1. The use of exhaled carbon dioxide to confirm tracheal intubation.
29
Q

What are some difficult airway techniques and equipment?

A
  • Equipment/techniques to manage difficult airway include, but are not limited to:
    • Awake intubation
    • Video-assisted laryngoscopy
    • Intubating stylets or tube-changers
    • SGA for ventilation
    • SGA for intubation
    • Rigid laryngoscopes
    • Fiberoptic guided intubation
    • Lighted stylets or light wands
    • Cricothyrotomy
31
Q

Preparing patient for awake fiberoptic?

What combo of drugs creates ideal conditions for awake fiberoptic?

A
  • Time and effort must be spent to prepare such patients both psychologically and pharmacologically for awake intubation
  • Combination of pre-procedure medications:
  • Ideal Sedation Conditions:
    • Anxiolysis
    • Amnesia
    • Analgesia
    • Suppression of gag and cough
    • Easily titratable
    • Minimal respiratory side effects
    • Rapidly reversible
  • Commonly used medications: use combo/stuff that can be reversed
    • Midazolam: repeated doses to achieve desired level of sedation/anxiolysis
      • Too much → AW can be affected
    • Fentanyl or remifentanil
    • Dexmedetomidine: sedative and analgesic effect without compromising ventilation (takes time)
    • Ketamine (popular choice)
    • Propofol: attenuates airway response (+/-)
    • Robinul: ensures a relatively dry field
    • Topical/inhaled/injected local anesthetics
    • Vasoconstrictors (phenylephrine or oxymetazoline hydrochloride)- highly vascular nasal mucosa
    • Consider aspiration prophylaxis

drug list not indicative of every institution

32
Q

Technique to perform awake fiberoptic technique?

A
  • Awake/minimal sedation: Allows the patient to breathe spontaneously, maintain airway patency, and cooperate with the operator
  • Airway nerve blocks
    • Glossopharyngeal nerve block: abolishes gag reflex (anesth posterior 2/3rd tongue, oropharynx, laryngopharynx, anterior surface epiglottis→ up to vallecula)
    • Superior laryngeal nerve block
    • Translaryngeal (Transtracheal) nerve block

awake fiberoptic video

glossopharyngeal blcok

33
Q

Methods to topically numb the glossopharyngeal nerve?

A
  • Topical – most common
    • Lidocaine soaked gauze
    • Lidocaine lollipop
    • Lidocaine spray 4% or 10%
    • 4% Lidocaine nebulizer
    • Cetacaine- rapid onset, 30-60 min duration
      • Caution- methemoglobinemia
      • “Spray as you go”
34
Q

What are the regional methods to block the glossopharyngeal nerve?

A

Regional- 2 approaches

  • Oral approach (for Glossopharyngeal nerve block)
    • 25g needle inferior to tonsil pillars (base of tongue)
      • after mouth numbed with lidocaine, can retract tongue medially better to access pillars
    • 1-2 mls 2% lidocaine (gargle)
      • Need sufficient mouth opening to access the pillars
      • point of injection at caudal aspect of posterior tonsillar pillar. ~0.5 cm lateral to edge of tongue where it joins edge of mouth
  • Peristyloid approach
    • Posterior to styloid process
      • glossopharyngeal N runs nearby
      • can palpate styloid process but requires deep palpation
      • pt in supine with head neutral. styloid process midpoint at angel to jaw to tip of mastoid process
      • place needle perpendicular aiming to hit styloid process. once contact made, walk needle posteriorly until contact lost
    • Close proximity to **internal carotid
      • 5-7 mls of 2% lidocaine (after negative aspiration)
35
Q

What are the approaches to block the superior laryngeal nerve?

A
  • Superior Laryngeal Nerve Block (2 approaches)- innervation to laryngeal structure above VC
    • Splits → internal/external branch
      • Internal branch→ penetrates thyrohyoid membrane 2 cm over greater cornu
      • External branch → descends on larynyx to sternohyoid muscle
  • External approach
    • Supine with neck extended (need ability to extend neck)
    • Identify the greater hyoid bone
      • Underneath angle of mandible
    • Displace hyoid toward clinician
    • Insert 23/25 g – 1.75 cm over inferior border of cornu and walk of bone inferiorly- inject 2 cc 2% lido. If you don’t pierce the thyrohyoid membrane, then external and internal SLN blocked
      • Pass through thyrohyoid membrane- if you pierce the thyrohyoid membrane, will only block internal branch.
    • Aspirate
    • Inject 1-2 mls of local (blocks internal/external branches of SLN)
    • Need to complete bilaterally….
      • If too far and penetrate thyrohyoid membrane → only will block internal branch (NO!)
  • Oral/internal:
    • Lidocaine soaked gauze in piriform fossae
    • 5-10 mins
36
Q

Methods to numb glossopharngyeal nerve for awake intubation? Purpose?

A

Topical or Regional

Prevent retching when posterior tongue lifted by laryngoscopy

video 1

video 2

39
Q

Method for recurrent laryngeal nerve block?

What does RLN supply?

A

(sensory VC/trachea)- direct blocks not performed not performed because you would block both sensory and motor, resulting in complete airway loss

  • Translaryngeal Approach
    • Injection of local anesthetic through cricothyroid membrane
    • Advance needle through membrane
      • 22 or 20 g needle- aim to penetrate cricothyroid membrane
    • Air bubbles in syringe signify placement into trachea lumen
    • Instruct the patient to exhale
    • Inject on inhalation- (rapid injection and then removal of needle results in coughing)
      • 3-5 mls of 2-4% lidocaine
    • Patient will cough…what you want – helps spread lidocaine
40
Q

Purpose/method of nasal topicalization for awake airway management?

A
  • Nasal topicalization
    • Anesthetizing sphenopalatine ganglion & anterior ethmoidal nerve
  • Vasoconstrictor- benefit
    • Oxymetazoline or phenylephrine
      • Increases size of nasal passage and decrease bleeding
      • make sure you give time for the meds to take effect
  • Anesthesia
    • Lidocaine soaked pledgets, cotton tipped applicator
    • Lidocaine gel
    • 4% lidocaine atomized
    • Leave in place 5-10 minutes- allows good topicalization of the nares.
41
Q

Steps to fiberoptic awake airway management?

A
  1. Sit patient as upright as tolerable
  2. Administer supplemental oxygen (via Hudson mask or nasal cannula)
  3. Attach full monitoring
  4. Start sedation. Careful with bolus dosing of medications.
    1. Titrate the dose according to the patient’s level of sedation. +/- BIS. Patient should remain cooperative, but comfortable
    2. Give stuff that can be REVERSED
  5. Start to topicalize the nasopharynx with lidocaine/vasoconstrictor solution.
    1. Achieved via atomization or cotton tip applicators
  6. Topicalize the oropharynx with 4% lidocaine using gauze or regional technique
  7. Consider dilating nares with nasal trumpets (progressive upsizing of ID)
    1. 6.5/7 → up to 8
  8. After topicalization, suction any secretions using a soft suction catheter
    1. → this also tests the effectiveness of the local anesthetic
  9. If patient does not tolerate the suction catheter → spray oropharynx with 2–4 sprays of 10% lidocaine
  10. Preload the fiberscope with a nasal endotracheal tube (ETT) (size 6/6.5 outer diameter [OD])
  11. Start fiberoscopy via the nasopharynx or oropharynx and visualize the vocal cords.
  12. Pass the fiberscope into the trachea
  13. “Railroad” the lubricated ETT over the scope gently into the trachea, trying not to touch the carina with the fiberscope
  14. Confirm correct placement of the ETT by visualizing the carina and ETT (consider deepening anesthesia at this point)
  15. Connect the ETT to the anesthetic circuit and capnography
  16. Gently inflate the cuff of the ETT (confirm capnography/ETCO2)
  17. Keep hold of the ETT until it has been safely secured

Video 1

Video 2

Video 3

42
Q

Common causes of failure of awake airway mgmt?

A
  • Common causes of failure:
    • Lack of experience
    • Failure to adequately dry the airway (not using glyco)
    • Failure to adequately anesthetize the airway
    • Bleeding
    • Obstruction of airway
    • Hang up – can see, but not pass ETT
    • Equipment malfunction

If unable to intubate but CAN ventilate → move to alternate approaches to achieve intubation! →

43
Q

What is an endotracheal tube introduecer?

A

ex- bougie

  • 15F – 70 cm long
  • 30° angled tip
  • Provides a guidewire
  • Useful for:
    • Suboptimal view
    • Anterior larynx (anterior AW)
    • Trach placement
    • Tube exchange
  • Placement
    • Hold 20 -30 cm from end
    • Place in the side of the mouth
    • Direct laryngoscopy or advance blindly – feel “clicks” along rings
      • Will stop (maybe)
    • Keep laryngoscopic view
    • Advance ETT – slowly rotate 90 degrees if hung up.

VIDEO

  • have equipment ready
  • Load ETT on bougie, form circle with top portion
  • optimize patient positioning, progressive laryngoscopy
  • once loaded and in trachea, make 90 degree turn to pass bevel
  • follow-through- anchor thumb to maxilla and hold tube, withdraw laryngoscope and pull out stylet while maintaining tube placement
44
Q

What are the criteria for difficult mask ventilation?

A

Criteria for Difficult Mask Ventilation:

  • Inability for one anesthesia provider to maintain SaO2 > 92%
  • Significant gas leak around the face mask
  • Need for > 4 L/min gas flow
    • Use of fresh gas flow button more than twice
  • No perceptible chest movement
  • Two handed mask required
  • > 20 – 25 cm H2O pressure to inflate the lungs
  • Change of operator required
    • ***Incidence of DMV varies from 0.08% to 15%.
      • Varies due to absence of universally accepted definition of DMV.
45
Q

What are risk factors for difficult mask ventilation?

A
  • Presence of beard - hard for air-tight seal
  • Body mass index – impair AW patency
  • Endentulous
  • Age > 55 years
  • History of snoring/OSA
  • Neck circumference
  • Gender- Males
  • History of difficult intubation
  • Mallampati 3-4
  • Severely limited jaw protrusion
46
Q

How is the SGA used in a difficult airway?

A
  • Prominent position in algorithms for rescue airway management
  • Relative ease of use
  • Relatively high success rates under adverse clinical conditions
  • Provide rescue ventilation/oxygenation- can provide PPV
  • Intubation conduit for emergent, elective cases (i-gel, air-Q, LMA Fastrach, Ambu Aura)
  • Intubate blindly (not recommended) or FFB-assisted (recommended)
  • Universally available
47
Q

How can we use a SGA to intubate with fiberoptic assistance?

A
    1. The ETT can be loaded onto the FIS, and the entire assembly can be passed through the LMA using visual guidance
    1. For cases where the desired ETT is too large in diameter to pass through the LMA, a more complex approach is needed, including the use of an Aintree intubation catheter (AIC), which is a modified airway exchange catheter.

VIDEO

48
Q

What are some techniques available in a can’t intubated, can’t ventilate scenario? Relative contraindications to those techniques?

A
  • Rare, but potentially catastrophic
  • Considered a true emergency- immediate lifesaving procedure is necessary
  • Types of emergency airways techniques:
    • Needle cricothyrotomy
    • Scalpel technique cricothyrotomy
    • Surgical cricothyrotomy
    • Surgical tracheostomy
  • Relative Contraindications:
    • Fracture of the larynx
    • Laryngotracheal disruptions
    • Transection of trachea
    • Young children (<12)
49
Q

Equipment and positioning for scalpel cricothyrotomy?

A
  • Equipment:
    • Scalpel (10 blade)
    • Bougie with coude tip
    • Cuffed ETT (6.0)
  • Positioning:
    • Supine
    • Neck extension – identify cricothyroid membrane
50
Q

Technique for scalpel cricothyrotomy?

A
  • Stand on pt’s left side (if right-handed, reverse if left-handed)
  • Perform laryngeal handshake
  • Stabilize larynx with left hand
  • Use left index finger to palpate cricothyroid membrane
  • Make transverse stab incision
  • Keeping scalpel perpendicular to the skin, turn blade 90 degrees (sharp edge toward feet)
  • Swap hands-hold scalpel in left and pick the bougie up with the right
  • Holding the bougie parallel to the floor, at a right angle to the trachea, slide the coude tip of the bougie down the side of the scalpel blade furthest from you into the trachea.
  • Rotate and align the bougie with the patient’s trachea and advance gently up to 10–15 cm.
  • Remove the scalpel.
  • Stabilize trachea and tension skin with left hand.
  • Railroad a lubricated size 6.0 mm cuffed tracheal tube over the bougie.
  • Rotate the tube over the bougie as it is advanced. Avoid excessive advancement and endobronchial intubation.
  • Remove the bougie.
  • Inflate the cuff and confirm ventilation with capnography.
  • Secure the tube.

VIDEO

  • Stab
  • Twitst
  • Bougie
  • Tube
51
Q

Complications to scalpel cricothyrotomy?

A
  • Bleeding (usually not severe)
  • Laceration of the thyroid cartilage, cricoid cartilage, or tracheal rings
  • Perforation of the posterior trachea
  • Unintentional tracheostomy
  • Passage of the tube into an extratracheal location
  • Infection
52
Q

Equipment needed for needle cricothyrotomy?

A
  • Commercial set-ups available
  • Universal precautions
  • Sterile drape
  • 10 cc syringe filled with sterile saline
  • Lidocaine for injection
    • Catheter size:
      • Infants and young children: 16-18 g
      • Adolescents and adults: 14-16 g
      • Alternative catheters include vessel dilators from central line kits
  • 7.0 ETT connector
  • Bag-valve-mask connector
  • Needle Cricothyroidotomy
53
Q

Techqniue for needle cricothyrotomy?

A
  • Needle cricothyroidotomy should be performed with universal precautions and sterile technique. The puncture site is cleansed with povidone-iodine solution after sterile gloves have been donned.
  • Hold the trachea in place and provide skin tension with the thumb and middle finger of the non-dominant hand placed on either side of the trachea. Use the index finger to palpate the cricothyroid membrane.
  • Hold a 3 to 10 mL syringe half-filled with saline attached to the over-the-needle IV catheter in the dominant hand.
  • Place the catheter in the midline of the neck at the inferior margin of the cricothyroid membrane (to avoid the cricothyroid blood vessels located superiorly and laterally). Direct it caudally (toward the feet) at an angle of 30 to 45 degrees.
  • Puncture the skin and subcutaneous tissue. Advance the catheter while continuously applying negative pressure on the syringe, until air bubbles are seen, confirming intratracheal placement.
  • Advance the catheter forward off the needle until its hub rests at the skin surface. Remove the syringe and the needle.
  • Reattach the syringe to the catheter and again aspirate for air to confirm that the catheter remains in the trachea.
  • Hold the catheter firmly in place at all times or delegate an assistant to do this to reduce the chance of kinking or dislodgement, even after it has been secured with suture material.
  • Needle Cricothyroidotomy
54
Q

Complications of needle cric?

A
  • Barotrauma – created high pressure system with small needle/jet ventilation technique can cause
  • Catheter issues
  • Subcutaneous emphysema
  • Bleeding
  • Damage to adjacent structures
55
Q

What is transtracheal jet ventilation?

A

can use w/ needle cricothyroidotomy

  • Connect to O2 Source
    • To DISS not machine
  • Open flow regulator ½ turn
  • Adjust pressure regulator to 20 – 20 psi
  • Attach to catheter/airway device
  • 15 - 20 breaths per minute
    • 1 second inhalation
    • 3-4 second for exhalation (reduces barotrauma)
      • CAUTION → major barotrauma
  • exhlation is passive!
56
Q

What is a retrograde wire technique?

A

particularly used for restricted mouth openings

  • Premade kits
  • Epidural kit plus
    • 20g angiocath
    • 3 ml syringe
    • Scalpel
    • Magill’s forceps
    • Hemostat
    • ETT
57
Q

Retrograde wire technique?

A
  • Premedicate if appropriate
  • Xylometazoline nasal drops along with lidocaine (2 %) jelly were used in the nasal passages. +- Bilateral superior laryngeal nerve block
  • The skin above the cricothyroid membrane was infiltrated with 1–2 ml of 1 % lidocaine
  • Cricothyroid membrane was punctured with a 16-gauge Tuohy epidural needle or angiocath
  • Tracheal placement confirmed by aspiration of air in a 4 % lidocaine-filled syringe and 1 ml of 4 % lidocaine was injected after confirming the placement
  • A J-tipped guide wire inserted through the needle
  • ETT was passed over the guide wire through the Murphy eye of the ETT, through the nostril or mouth
  • The guide wire was removed, and the ETT was further introduced in the trachea
  • Tracheal placement was confirmed by capnography

VIDEO

58
Q

What is transtracheal jet ventilation?

A

can use w/ needle cricothyroidotomy

  • Connect to O2 Source
    • To DISS not machine
  • Open flow regulator ½ turn
  • Adjust pressure regulator to 20 – 20 psi
  • Attach to catheter/airway device
  • 15 - 20 breaths per minute
    • 1 second inhalation
    • 3-4 second for exhalation (reduces barotrauma)
      • CAUTION → major barotrauma
  • exhlation is passive!
59
Q

When might patients be at increased risk for complications during extubations?

A
  • Paradoxical vocal cord motion
  • Thyroid surgery
  • Tracheomalacia
  • Diagnostic laryngoscopy
  • Uvulopalatoplasty
  • Sleep apnea
  • Maxillofacial trauma
  • Parkinson’s disease
  • Rheumatoid arthritis
  • Inadequate airway protective reflexes
    • Positioning: prone/prolonged Trendelenburg → fluid overload and edema!!
60
Q

What are some criteria for awake extubation?

A

Subjective

  • Follows commands- open eyes, squeeze fingers, etc
  • Clear oropharynx/hypopharynx- sx mouth
  • Intact gag reflex
    • Coughing/gaging on ETT
  • Sustained head lift for 5 seconds
  • Hand grasp
  • Adequate pain control
    • Ex: abdominal sx**

Objective

  • Vital capacity > 10 ml/kg
  • Peak negative inspiratory pressure > -20 cm H20
  • Tidal volume > 6 cc/kg
  • TOF ration > 70%
  • Aa gradient < 350
61
Q

Steps involved for extubation from low-risk algorithm?

A
  • 100% O2
  • Remove sx
  • Insert bite block
  • Sitting position
  • Reverse NMB
  • SV- normal RR
  • Minimize head and neck movement
    • Provide PPV
    • Deflate cuff
    • Remove ETT
  • Continue O2 supplement
62
Q

At risk algorithm for extubation?

What are some exclusions for extubation?

A
  • Risk factors present
    • Preexisting difficulty:
      • Ex: Obesity/OSA, pts w/ risk for aspiration
    • Perioperative AW deterioration:
      • AW normal @ induction → then become diff
        • Ex: distorted anatomy, hemorrhage, hematoma, edema from sx/trauma/nonsx factors
    • Restricted AW access
      • Ex: shared AW, ROM limited
  • Exclusion of extubation:
    • Impaired resp fx
    • CV instability
    • Neurologic/neuromuscular impairment
    • Hypo/hyperthermia
    • Clotting abnormalities
    • Acid/base or electrolyte imbalances
64
Q

How do you use an airway exchange catheter (AEC)?

A
  1. Depth of AEC. Distal tip must remain above carina (never beyond 25 cm)
  2. Insert lubricated AEC through ETT
  3. Employ pharyngeal suction
  4. Remove ETT over AEC. Monitor depth
  5. Secure AEC to cheek or forehead
  6. Record depth at teeth/lips/nare (label)
  7. Check that there is a leak
  8. Supplemental oxygen applied
  9. If not tolerated, check depth, inject lidocaine
  10. Remain NPO
  11. Must go to ICU
  12. Can be tolerated up to 72 hrs (before being removed)
66
Q

What is an airway exchange catheter (AEC)?

A

used as stylet for new ETT

→ can use as “insurance policy” in case unsure if need to reintubate

  • Multiple different types – Cooks most common
  • Diameter 2.7 – 6.33 mm and 45 – 83 cm in length
  • Central lumen with rounded edges – can be used for insufflation
  • Prior to placement, the patient should meet extubation criteria
  • Breathing 100% oxygen
  • Use the largest tube – place in mid-trachea
  • Complications:
    • Loss of airway control
    • Mucosal trauma
    • Pneumothorax
68
Q

What is the Baily maneuver?

A
  • Substitution of ETT for LMA during deep anesthesia
    • Good for pts w/ high AW reactivity
  • Removal of LMA when patient resumes spontaneous respirations and obeys commands
  • Patient needs to be at sufficient depth to prevent coughing, breath holding, laryngospasm, and hemodynamic stimulation
  • Maintain oxygenation and ventilation
  • Allows for fiberoptic re-intubation
    • Advantages: Well-seated SGA allows for..
      • Resumption of SV w/ controlled depth of anesthesia/supp O2
      • Prevents secretions away from larynx (increases view of glottic/subglottic anatomy)
      • Useful for pts w/
        • suspected paradoxical VC motion
        • laryngeal nerve dysfx
        • tracheomalacia
69
Q

What might you administer to limit coughing and bucking during extubaiton? Example of surgeries to have smooth emergence?

A
  • To limit coughing and bucking and hemodynamic alterations:
    • Low dose remifentanil
    • Dexmedetomidine
    • Lidocaine
    • Esmolol
  • Example of Pts to avoid coughing/bucking:
    • Neurosx
    • Maxilofacial
    • Plastics
    • Severe CV dx