Search the Protocols

List of Donors

Make a donation to the protocols online

KLS Martin, LP

Hemostatix Medical Technologies, LLC

Cook Medical

Karl and Kay Rinehart

Boston Medical Products Inc.

Lumenis

Jon and Veda Foster

KayPentax

Synovis Micro Companies Alliance, Inc

Tom Benda, JR., M.D.

The Potash Family

UIHC Melanoma and Sarcoma Tissue Bank

Karl Storz-Endoskope

Heartland Regional Chapter of SOHN

 

 

The Department of Otolaryngology and the University of Iowa wish to acknowledge the support of those who share our goal in improving the care of patients we serve. The University of Iowa appreciates that supporting benefactors recognize the University of Iowa's need for autonomy in the development of the content of the Iowa Head and Neck Protocols.

HaN Admin Pages

Skip to end of metadata
Go to start of metadata

Redirecting to: https://medicine.uiowa.edu/iowaprotocols/difficult-airway see also: Pediatric Airway; Airway Monitoring Manangement Protocols; Emergency Airway Cart; Heliox for the difficult airway

see also: Tracheostomy and Upper Airway Management Symposium July 30 2016 IAO and SOHN Iowa City Iowa

   and: Pulse Oximetry Basic Principles and Interpretation

 Pulse Oximetry common misconceptions regarding use

  1. General Considerations
    1. Ascertain the lowest level of airway obstruction; attain airway control below that level.
      1. Oral cavity, oropharyngeal, hypopharyngeal, supraglottic, glottis, subglottic, tracheal, bronchial
    2. Be aware of associated medial conditions
      1. Cervical spine: Trauma patients and Down Syndrome patients who are at high risk for injury should be appropriately evaluated pre-operatively, and sandbagged with the head in neutral position if necessary
    3. Select the simplest form of control that is adequate.
    4. Call for assistance if difficult airway predicted
  2. Airway assessment
    1. Signs of airway distress:
      1. Stridor:
        1. Inspiratory: obstruction at or above the thoracic inlet
        2. Expiratory:  obstruction at or below thoracic inlet
          1. Example: croup, subglottic stenosis
        3. Inspiratory and expiratory: obstruction at true vocal cords
      2. Hoarseness: suggests injury at the glottic level, suspect severe injury if complete aphonia
      3. Poor air movement
      4. Accessory muscle use: suprasternal retractions and tripod stance
      5. Drooling: indicative of hypopharyngeal/laryngeal obstruction
      6. Bleeding: determine if bleeding is below palate, therefore in airway
      7. Subcutaneous emphysema: rupture in aerodigestive tract
      8. Palpable fracture:
        1. Thyroid & trachea: laryngeal fracture
        2. Palate or mandible: oropharyngeal airway obstruction
      9. Hypoxia
        1. Restlessness and agitation
        2. Cyanosis
    2. Definition of a difficult airway:
      1. Difficult intubation has been defined as one that requires external laryngeal manipulation, laryngoscopy requiring more than 3 attempts at intubation, intubation requiring nonstandard equipment or approaches, or the inability to intubate at all
      2. ASA practice guidelines “a difficult airway is defined as the clinical situation in which a conventionally trained anesthesiologist experiences difficulty with face mask ventilation of the upper airway, difficulty with tracheal intubation, or both”.
        1. Subdivision of difficult airway into four categories:
          1. Difficult face-mask ventilation
          2. Difficult laryngoscopy
          3. Difficult tracheal intubation
          4. Failed intubation
    3. Signs of difficult airway
      1. Trismus: interincisor distance of 3 cm or less
      2. Small mandible: Thyro-mental distance 6 cm or less
      3. Snoring/sleep apnea, dyspnea when supine
      4. Secretions
      5. Mallampati classification of 3, 4- cannot see uvula when mouth is opened
      6. Poor cardiopulmonary reserve
      7. Anatomic alterations- short neck, thick neck, neck in fixed flexion or poor range of motion, prominent incisors, prominent “overbite”, high arched palate/narrow palate, firm floor of mouth,  post radiation changes, scarring, large masses
    4. Disease states associated with difficult airway management
      1. Congenital
        1. Pierre Robin Syndrome
        2. Treacher-Collins syndrome
        3. Goldenhar’s syndrome
        4. Mucopolysaccharidoses
        5. Achondroplasia
        6. Micrognathia
        7. Down’s syndrome
      2. Acquired
        1. Morbid obesity
        2. Acromegaly
        3. Airway infections (Ludwig’s angina)
        4. Rheumatoid arthritis
        5. Obstructive sleep apnea
        6. Ankylosing spondylitis
        7. Tumors involving airway
        8. Trauma
    5. Predictors of a significantly difficult or impossible intubation in pediatric population
      1. Small mouth aperture, hyomental distance 1.5 cm or less in a newborn or infant and 3 cm or less in a child
      2. Head and neck impaired mobility
      3. Micrognathia, retrognathia, mandibular dysplasia/ hypoplasia, macroglossia
      4. Space occupying airway lesions
      5. Supralaryngeal inflammatory pathology
      6. Nasal airway obstruction or craniofacial abnormalities
      7. Obesity
  3. Tools to use in Non-Emergent Situation
    1. Temporary options, Simple ways to stabilize the airway
    2. Awake Patient
      1. Humidified Oxygen
      2. Positioning: neck extension, chin lift (Fingers placed under mandible to lift open, thumb used to open lips)
      3. Nasal Airway
        1. Obtunded patient with mandibular retrusion
        2. Oral cavity/oropharyngeal obstruction
        3. Better tolerated than oral airway in responsive patient.
        4. Don’t use if suspected skull base fractures
      4. Bag-Mask Ventilation with goal to maintain saturation >90%
        1. If not, this is failed airway
        2. Risk factors for poor bag mask ventilation: >55, BMI >26 kg/meter squared, beard, lack of teeth, and history of snoring, large hypopharyngeal tongue, lingual tonsil hyperplasia
    3. Anesthetized patient: same as above
      1. Jaw thrust: Grasping the angles of the lower mandible, one hand on each side, to displace mandible forward
      2. Oral airway: base of tongue obstruction in altered patient, not tolerated well in awake patient, make sure to position correctly
      3. Trans-tracheal needle ventilation
        1. Used if Bag Mask cannot keep above 90% and determined difficult airway
        2. Provides rapid oxygenation while more definitive management is underway (best in kids)
          1. 12-14 gauge needle through cricothyroid membrane into trachea
          2. Connect to wall oxygen 15 l/min
          3. Intermittent insufflation with one second on, 3-4 seconds off
          4. 30-45 minutes maximum due to CO2 accumulation
    4. Medications/Non Surgical Adjuncts
      1. Steroids
      2. Racemic epinephrine
      3. Heliox: (at least 70% Helium to be effective)
        1. Glottic obstruction- use low flow rates (5-7 l/min) d/t risk of tension pneumothorax
        2. Helium is of lower density than the nitrogen found in air, and thus, its use instead of nitrogen decreases airway resistance, lessens the work of respiration, and may help alleviate oxygenation deficits secondary to obstruction.
  4. Definitive Airway: advanced ways of stabilizing the airway
    1. Indications for Definitive Airway
      1. Apnea
      2. Inability to maintain a patent airway by other means
      3. Protection of the lower airway from aspiration of blood or vomitus (GCS<8)
      4. Closed head injury requiring prolonged comatose state
      5. Airway in the Trauma Patient
      6. Potential Airway Issues
        1. Laryngeal fractures
        2. Airway and pharyngeal burns
        3. Tongue swelling
        4. Neck injuries
    2. Oral Intubation
      1. Indications:
        1. Progressive upper airway obstruction
        2. Worsening pulmonary status
        3. Loss of respiratory drive
      2. Contraindications (all are relative)
        1. C-spine fracture (hyperextension)
        2. Laryngeal trauma (difficult to intubate, may make trauma worse)
        3. Severe oral trauma (unable to visualize glottis for intubation)
      3. Consideration of basic management choices
        1. Awake intubation versus intubation after anesthesia given
        2. Invasive versus non-invasive techniques
        3. Spontaneous ventilation versus ablation of spontaneous ventilation
    3. Flexible Fiberoptic Nasal Intubation
      1. Indications
        1. C-spine injury
        2. Oral cavity injury
      2. Advantages
        1. Laryngeal visualization
        2. Suction
        3. Can be done awake
          1. For an awake fiberoptic intubation, the patient should be given a full explanation
          2. topical oral or nasal anesthesia, tracheal and laryngeal local anesthesia, and minimal sedation.
          3. An antisialagogue should be administered, and if nasal intubation is used, the nasal mucosa should be anesthetized and vasoconstricted with a lidocaine-phenylephrine combination.
      3. Disadvantages
        1. Requires expertise
        2. Bleeding dramatically decreases visibility
        3. Slower than orotracheal intubation
      4. Technique
        1. Decongest nasal cavity with Afrin
        2. Transnasal placement of flexible scope after passing through the endotracheal tube
        3. Passed through the nose, nasopharynx, palate, oral cavity, and supraglottis. 
        4. Spray local onto the vocal cords through side port, suction and/or oxygen can be hooked up as well
        5. Endoscope introduced into the subglottic trachea and endotracheal tube passed over the endoscope
      5. Blind Nasotracheal Intubation
        1. Can be performed without visualizing larynx (this is advantage and disadvantage)
        2. Indications:
          1. Fiberoptic equipment unavailable
        3. Contraindications:
          1. Severe midfacial fractures or basilar skull fracture (“nasocranial intubation”)
    4. Direct Laryngoscopy/Bronchoscopy
      1. Indications: unable to visualize larynx with other methods
      2. Advantages: Direct visualization, ability to ventilate patient directly through bronchoscope
      3. Disadvantages: Cannot perform if C-spine injury suspected
      4. Must have equipment immediately available
      5. Lighted stylet is way to intubate and examine concurrently
      6. Cormack-Lehane View Classification
        1. Grade 1: entire glottis visible
        2. Grade 2: only the posterior portion of the glottis can be seen
        3. Grade 3: only epiglottis can be seen
        4. Grade 4: cannot see epiglottis
      7. External laryngeal manipulation may help
    5. Laryngeal Mask Airway
      1. Advantages
        1. This is supraglottic device , you do not need to visualize glottis to use technique.
        2. A decreased rate of laryngospasm has been shown through the use of an LMA
        3. An intubating LMA can be used as a quick way to secure an airway in an unstable situation.  A 2.0 intubating LMA can be placed, and a 4.0 ET tube can be threaded through this secured LMA and subsequently placed into the airway.  Placement of this tube should be performed over a flexible fiberoptic scope.  A stylet is then placed on the end of the ET tube to hold it in place while the intubating LMA is withdrawn.
        4. May be used to pass bronchoscope/tube changer to intubate
      2. Disadvantages:
        1. Not a secure airway (may become displaced)
        2. Non-traumatic settings when obstruction is thought to be temporary
    6. Combitube
      1. Double lumen tube
      2. Blind intubation into trachea or esophagus
      3. Proximal and distal cuffs
      4. Determine which lumen ventilates lung after placement.
    7. King LT
      1. Similar to Combitube- single lumen, larger proximal cuff
      2. UIHC experience: can make subsequent evaluation difficult (Khaja et al., Arch Otolaryngol Head Neck Surg Sep 2010)
    8. Cricothyroidotomy if unable to ventilate with a mask and failed attempts at tracheal intubation with advanced airway  
      1. Indications:
        1. Unable to Mask and Failure of intubation
        2. No laryngeal injury
        3. Failed ventilation with advanced airway
      2. Advantages
        1. Direct entry to airway à good airway control
        2. More rapid than tracheotomy
      3. Disadvantages:
        1. Surgical procedure
        2. Can cause acute & chronic laryngeal injury
      4. Needle Cricothyroidotomy Technique:
        1. Needle inserted through skin and cricothyroid membrane, downward 45 degree angle while withdrawing
        2. Attach to oxygen delivery device
      5. Slash Cricothyroidotomy Technique:
        1. Palpate landmarks: laryngeal prominence, cricoid prominence
        2. Stabilize and compress skin over larynx and cricoid
        3. Stay in the midline with 3 cm vertical skin incision, transverse stab incision through cricothyroid membrane, rotate 90 degrees or clamp spread in membrane
        4. Insert finger to dilate/confirm access
        5. Estimated time~20 seconds with blade, hook, tube, and sponge
        6. 6-0 ETT or appropriate sized ETT into airway
        7. After airway secured and patient stabilizes, convert to tracheotomy to prevent long-term complications
    9. Tracheotomy
      1. Indications:
        1. laryngeal trauma
        2. failure of above techniques
        3. URGENT need for airway
      2. Advantages:
        1. direct, well-visualized access into airway
        2. avoids entry into larynx
      3. Disadvantages:
        1. more time consuming
        2. more difficult to perform in emergent setting
      4. Technique for slash tracheotomy
        1. Vertical incision from cricoid to sternal notch
        2. Vertical dissection down to the airway
        3. Palpate cricoid to assess location of 2nd tracheal ring
        4. Transverse incision into airway below 2nd ring
    10. Emergency airway kits- adjuncts to armamentarium
      1. A bougie is a semirigid elastic tube that is a 60-cm, 15-French stylet with a curve 3.5 cm from the distal tip
      2. The bougie may be inserted under the tip of the epiglottis when the vocal cords cannot be visualized using DVL and cricoid pressure
  5. Pediatric Airway Cart Checklist (pending final approval of Bonnia Ropp)
    1. Mask with Face Shield
    2. Wire Cutter in sterile package from central processing
    3. Surgical Lubricant
    4. 18 gauge needle
    5. Sterile 4x4
    6. 16, 18, 20, 22 gauge angiocatheters
    7. Tongue Blades
    8. Sterile Cotton Swabs
    9. 10, 14  French oxygen catheters
    10. Yankauer suction
    11. Infant, Pediatric and Adult tracheal dilator in sterile package from central processing
    12. 16, 18, 20, 22, 24, 26, 28, 30, 32, 34 French Nasopharyngeal Airway 
    13. 9, 10 cm Williams Intubator Airway (pink Oropharyngeal airway used for Flexible fiberoptic intubations, cannot be removed while FFL is being used in patient)
    14. 5, 6,7, 8, 9 cm Gudedel Airway (clear Oropharyngeal airway, color ring at mouth opening coordinated with size)
    15. 8, 9, 10 cm Berman Intubating/Pharygeal Airway (color/size coordinated Oropharyngeal airway used for Flexible fiberoptic intubations, open groove allows airway to be removed with FFL in place)
    16. Pediatric and Adult Tracheal Light Wand
    17. Light Wand Handles
    18. AA Batteries
    19. LMA 1 with 5ml syringe, LMA 1.5 with 10ml syringe, LMA 2 with 20ml syringe, LMA 2.5 with 20ml syringe, LMA 3 with 30ml syringe, LMA 4 with 30ml syringe, LMA 5 with 60ml syringe,
    20. LMA Fasttrach ETT #3, #4, #5 in sterile package from central processing
    21. Pediatric ( > 3mm), Small ( > 4mm), Medium ( > 5mm), Large ( > 7mm) Cook Airway 14 French Cook Retrograde Intubation Kit
    22. 6mm, 4mm, 3.5mm Melker Emergency Cricothrotomy Kit
    23. Emergency Transtracheal Airway Catheter (6f x 7.5cm)
    24. End Oxygen Flo Modulator set 100 (6f x 7.5cm)
    25. Rigid laryngoscope in multiple sizes with both straight and curved blade
    26. Cuffed endotracheal tubes ranging from 2.0 to 8 mm ID
    27. CO2 detector 
  6. Sources
  1. Practice Guidelines for Management of the Difficult Airway. Anesthesiology May 2003. pp 1269-1277.
  2. Berkow.  Strategies for airway management.  Best practice & research clinical anesthesiology.  Vol 18. No 4, pp 531-548, 2004
  3. Baileys and Johnson.  Head and Neck Surgery: Otolaryngology. Sixth ed. 2006
  4. Lewis. Cummings Otolaryngology: Head and Neck Surgery. Fourth ed. 2007 
  5. Khaja et al.  Arch Otolaryngol Head Neck Surg. Sep 2010

The contents of this web site are for information purposes only, and are not intended to be a substitute for professional medical advice, diagnosis, or treatment. The University of Iowa does not recommend or endorse any specific tests, physicians, products, procedures, opinions, or other information that may be mentioned on this web site. Although the standards discussed herein reflect the University of Iowa's head and neck protocols, reliance on any information provided herein is solely at your own risk.

  • No labels