Airway (Exam II) Flashcards
How many turbinates are there?
What is another name for turbinates?
Three (also known as meatus)
- Inferior
- Middle
- Superior
Which turbinate does the endotracheal tube pass through during a nasal intubation?
- Inferior turbinate
What is necessary for bleeding reduction during nasal intubation?
- Vasoconstrictors (ex. oxymetazoline)
What area is considered the pharynx?
- Base of skull to lower border of cricoid cartilage.
What area is indicated by 1 on the figure below?
Nasopharynx
What area is indicated by 2 on the figure below?
Oropharynx
What area is indicated by 3 on the figure below?
Hypopharynx
What structure divides the oropharynx and the hypopharynx?
- Epiglottis
Loss of pharyngeal muscle tone results in _________ _________.
Airway obstruction - the nasopharynx ends at the soft palate, this region is termed velopharynx, and is a common site of airway obstruction
Fill in the structures that compose the picture of the larynx below.
What structure is indicated by 1 on the figure below?
- Median glossoepiglottic fold
What structure is indicated by 2 on the figure below?
- Lateral glossoepiglottic fold
What structure is indicated by 3 on the figure below?
- Aryepiglottic fold
What structure is indicated by 4 on the figure below?
- Ventricular fold
What structure is indicated by 5 on the figure below?
- Vocal fold
What structure is indicated by 6 on the figure below?
- Trachea
What structure is indicated by 7 on the figure below?
- Corniculate Cartilage
What structure is indicated by 8 on the figure below?
- Cuneiform Cartilage
What structure is indicated by 9 on the figure below?
- Piriform Recess
What structure is indicated by 10 on the figure below?
- Tubercle of Epiglottis
What structure is indicated by 11 on the figure below?
- Epiglottis
What structure is indicated by 12 on the figure below?
- Vallecula
What vertebrae corresponds with the very bottom of the larynx?
- 6th cervical vertebrae
What is the purpose of the larynx?
- Inlet to trachea
- Phonation
- Airway protection
*it is suspended from the hyoid bone by the thyrohyoid membrane
Which laryngeal cartilages are unpaired?
- Thyroid (largest, supports soft tissue)
- Cricoid - complete ring
- Epiglottis
Which laryngeal cartilages are paired?
- Arytenoid
- Corniculate
- Cuneiform
What do the vocal cords attach to?
- Arytenoids
- thyroid notch on the thyroid cartilage
How far does the trachea span?
What supports it anteriorly and posteriorly?
- From the inferior cricoid membrane to the carina (10 - 15 cm).
- Posterior: longitudinal trachealis muscle
- Anterior: Tracheal rings (bougie intubation)
Is airway history or assessment more valuable?
- Airway history
What portions of patient history can be a cause for airway concern? Which is most important?
- Past difficult airway
- Report of sore throat
- Report of cut lip or broken tooth
- Recent hoarseness
- Hx of OSA
What is a better indication of airway difficulty than BMI?
- Thick neck greater than 43cm
What are the factors in the Airway Evaluation
- Visual inspection of the face and neck
- Assessment of mouth opening
- Evaluation of oropharyngeal anatomy and dentition
- Assessment of neck range of motion (sniffing position)
-Assessment of the submandibular space - Assessment of the pt’s ability to slide the mandible anteriorly
What factors that are assessed visually would give one concern for a potentially difficult airway?
- Facial deformities
- Head & neck cancers
- Burns
- Goiter
- Short/Thick neck
- Receding mandible
- Large beard
- C-collar
What inter-incisor distance is best?
- > 6cm (3 finger breadths)
What to evaluate in the oropharyngeal anatomy
Identify pathololigic characteristics
-Tumor
-Palate deformities
High arched palate or cleft
-macroglossia
Dental Assessment factors
- Long upper incisors
- Poor dentition/loose teeth = increased risk of dental trauma
tooth dislodged/aspiration - Cosmetic work
- Edentulousness = difficult to mask ventilate
Dental injuries
25% of insurance claims were against anesthesia providers
75% occur during trachea intubation
Most frequently injured teeth during ET intubation are the anterior maxillary central and lateral incisors
What is the sniffing position?
Why does it make intubation easier?
- Cervical flexion and antlanto-occipital extension
- Aligns oral, pharyngeal, and laryngeal axes.
What technique is depicted below?
Why is it used?
- Ramping: used for positioning larger patients.
What is the sternomental distance?
What is an indicator of a potentially difficult airway?
- Distance between sternal notch and chin with head fully extended and mouth closed.
- Less than <12.5 cm
What is thyromental distance measuring?
What would be preferred?
- Submandibular compliance (tip of chin to thyroid notch)
- > 6.5cm preferred (3 finger breadths)
How is prognathic ability measured?
- Upper lip bite test (assesses how much lower incisors can extend beyond upper incisors)
What structures should be visible in a Mallampati class I?
- Fauces
- Tonsillar pillars
- Entire uvula
- Soft palate
What should be visible in a Mallampati class II?
- Fauces, portion of uvula, and soft palate
What should be visible in a Mallampati class III?
- Base of uvula and soft palate
What should be visible in a Mallampati class IV?
- Only the hard palate
What is BURP?
- Backward, Upward, and Rightward pressure to facilitate intubation.
What is Optimal External Laryngeal Manipulation (OELM) ?
- Moving someone else’s hand over external neck until a proper view is seen.
What Cormack-Lehane view is depicted below? What is visible with this view?
- CL - 1
- Entire glottis is visible
What Cormack-Lehane view is depicted below? What is visible with this view?
- CL - 2
- Posterior of glottis is visible
What Cormack-Lehane view is depicted below? What is visible with this view?
- CL - 3
- Only the epiglottis is visible
What Cormack-Lehane view is depicted below? What is visible with this view?
- CL - 4
- Epiglottis can’t be visualized.
Criteria associated with difficult mask ventilation (OBESE)
O: Obesity (BMI>30)
B: Beard
E: Edentulous
S: Snores/OSA
E: Eldery, make (age>55)
Mallampati 3 or 4
Predicting the difficult airway (BOOTS)
Beard, Obesity, Older, Toothless, Sounds (snoring/stridor), Inability to maintain O2 sats>90% with BMV
Difficult intubation (LEMONS)
-Look at the face and neck (trauma, unusual anatomy)
-Evaluate 3-3-2 rule (3 finger mouth opening, 3 fingers along floor of mandible, 2 fingers between superior notch of the thyroid cartilage and the neck/mandible junction
-Mallampati score
-Obstruction/obesity (tumor or infection)
Neck mobility
1000% know this picture
here is it again
Difficult airway algorithm: Pre-intubation
Pre-intubation, choose between awake or a post-induction airway strategy
-suspected difficult laryngoscpy, ventilation with face mask
- significant risk for aspiration
-risk of rapid desat
-suspected difficult emergency or invasive airway
**Any one factor alone may be clinically important to warrant an awake intubation
Limit intubation attempts and consider calling for help quickly, or consider awakening the pt
RSI vs awake intubation factors to consider
-urgency (perri-arrest vs stable)
-Difficult airway features
-vomiting risk
-sympatholysis and apnea risk
Awake intubation technique
Favored in patients who require intubation less urgently, have more difficult airway features, and are not high risk for vomiting
Glycopyrolate 0.2 mg or Atropine .01 mg/kg glyco preferred
Suction then pad dry mouth with gauze
Nebulized Lidocaine without epi @ 5 lpm ideally 4 cc of 4% lidocaine but can also use 8 cc of 2% lidocaine
Preoxygenate
Lightly sedate with Versed 2-4 mg or Ketamine 20 mg
Intubate awake or place bougie, then paralyze, then pass tube
The Bougie
-self-confirming
-can intubate epiglottis-only views
- black stripe is 25 cm - at lips, mid trachea in an adult
Problems/contraindications to succinylcholine
(Rabi K Must Sit At the Trophy Nerve Bridge, because Craig Tends to Serve Irish)
-rhabdomyolysis
-existing hyperkalemia
-multiple sclerosis
-ALS
-muscular dystrophies
-denervating injuries > 72 hours old (e.g. stroke, spinal cord injury) burns > 72 hours old
-crush injury > 72 hours old
-tetanus, botulism, and other exotoxin infections
-severe infections >72 hours old (esp. intra-abdominal infections)
-immobilization (including patients found down)
Contraindications to Rocuronium
Physiologic Killers (3)
- Hypotension (shoot for higher than normal BPs before intubating if possible)
- Hypoxemia
- Metabolic Acidosis
Pressors we can push
- Epinephrine: Epinephrine should be the pressor agent of choice to give push dose because it possesses, both an alpha and beta agonist, as this not only increases vascular resistance and blood pressure, but through its beta agonist effect also increases cardiac output.
- Phenylephrine: a pure alpha agonist, increases vascular resistance and blood pressure, but will decrease cardiac output and venous return due to the lack of effect at the beta receptors.
- Vasopressin: easy mixing, doesn’t require complicated dilution, patients in profound state of shock may respond better than to alternatives
Intervention 1 for desatting pt, but awake and breathing
NC 15LPM + BVM 15LPM + PEEP Valve 5 – 15cmH20
They’re breathing, keep a good seal and let the magic happen
Intervention 2 for a desatting pt - uncooperative or combative
Delayed Sequence Intubation (DSI)
Procedural sedation for the procedure of preoxygenation
Give 1mg/kg IV Ketamine -> Preoxygenate -> Paralyze the Patient -> Apneic Oxygenation -> Intubate
Metabolic acidosis
**Try and avoid intubation in these patients if at all possible
Intervention 1: Bicarbonate - Patients in severe metabolic acidosis are already tachypneic in an effort to blow off CO2, so any further CO2 could make them more acidotic and lead to cardiac dysrhythmias (so be careful)
Intervention 2: Ventilator Assisted Pre-Oxygenation - If intubation does become necessary maintaining spontaneous respirations is a critical action because maintenance of acid-base homeostasis is dependent on a respiratory alkalosis
Key points
you cannot predict the difficult airway – have a plan for failed intubation and failed ventilation and be ready to carry out that plan
initiate rescue maneuvers such as ventilation and cricothyrotomy early so that the patient has enough reserve to allow for calm and effective execution
BVM with three airways in, two hands down replace BVM with LMA ventilation
make the bougie part of your routine
ask the question: should I use an awake technique? rocuronium
use a checklist to keep you focussed on what’s important