Benumof, JL. The ASA Difficult Airway Algorithm: New Thoughts/Considerations. 1998 ASA Annual Refresher Course Lectures, course number 236.
1. Describe some of the factors that predict difficult airways
2. Be aware of options for management of the difficult airway
1. What factors predict difficult intubation?
2. What factors predict difficult mask ventilation?
3. What are the options for anesthetic management in cases of known difficult intubation?
4. How long should you try to intubate, or how many attempts should you make, before you decide that the patient cannot be intubated with conventional direct laryngoscopy?
5. Describe management of the unrecognized difficult intubation (e.g., you do a rapid sequence induction with sodium thiopental and succinylcholine; on your first laryngoscopy you see only tongue and palate).
6. How do you optimize your ability to mask ventilate a patient?
7. Describe how the LMA and Combitube work.
8. How do you prevent future airway difficulties?
1. Long protruding upper incisors, inability to protrude mandible teeth anterior to maxillary teeth (TMJ function), narrow-opening mouth, large tongue, narrow palate, short jaw (mandible; thyromental distance), poor compliance of mandibular space (e.g. s/p radiation therapy), short neck, limited neck range of motion, history of difficult intubation (review chart!).
2. Abnormal anatomy (tumor, disruption), beard, obesity
3. Regional anesthesia if possible for surgery, surgery can be ended quickly if necessary, and have access to airway during procedure; general anesthesia (GA) with awake intubation (fiberoptic, blind nasal, retrograde, light wand, tracheostomy); GA with intubation after induction (required surgery, patient uncooperative; cancel case.
4. As soon as you realize you are having difficulty, you should make an optimal/best attempt (experienced endoscopist, no significant patient muscle tone, optimal sniff position, optimal external laryngeal pressure, optimal length and type of blade [may change each once]). If this attempt fails, move on the next step in management. Consider calling for help early.
5. Check if you can mask ventilate (optimal attempt; #6). If you can, you have all the choices listed in #3 and #4. You can also give GA with mask ventilation. If you cannot mask ventilate, consider LMA (Fastrach-LMA if experienced), Combitube, transtracheal jet ventilation, and emergent tracheostomy.
6. 2-person effort to optimize jaw thrust and mask seal, large oropharyngeal airway, and bilateral large nasopharyngeal airways.
7. LMA. Combitube. Can intubate through the LMA. Supraglottic devices – for glottic or subglottic problems (spasm, edema, tumor, abscess, etc.) need jet ventilation [if patient can exhale], ETT, or tracheostomy).
8. Notify patient and patient’s physician, in writing, of difficulty. May advise patient to wear Medic Alert bracelet indicating difficulty.