Airway Flashcards
What spinal cord level is the larynx located at?
C3-C6
What are three functions of the larynx?
Airway protection, respiration and phonation
From where to where is the larynx located?
From the epiglottis to the cricoid cartilage.
What are the paired cartilages of the larynx?
Arytenoid, corniculate and cuneiform.
What are the unpaired cartilages of the larynx?
Cricoid, thyroid and epiglottis
What is the narrowest point of the pediatric airway?
Cricoid cartilage
What nerve supplies most of the intrinsic laryngeal muscles?
The recurrent laryngeal nerve (a branch of the vagus nerve)
What nerve supplies the cricothyroid muscle?
The external branch of the superior laryngeal nerve.
What are the intrinsic muscles that adduct or close the glottis?
Lateral cricoarytenoid and Arytenoids.
What is the intrinsic muscle that abducts the vocal cords?
Posterior cricoarytenoid.
What intrinsic laryngeal muscle elongates or puts tension on the vocal cords?
The cricothyroid.
What two intrinsic laryngeal muscles shorten and relax the vocal cords?
Vocalis and thyroarytenoid.
What are the 4 extrinsic muscles of the larynx?
Sternohyoid, thyrohyoid, omohyoid, and sternothyroid.
What are some questions to consider during an airway evaluation/history?
Radiation of burn to head/neck? C-spine pain or LROM? TMJ pain? Rheumatoid arthritis? Ankylosing spondylitis? Abscess or tumor? Prior intubation or tracheotomy? Snoring or sleep apnea? Dysphagia or stridor?
What can you see with Mallampati class I, 2, 3 and 4?
1: Facil pillars, soft palate, uvula.
2: Uvula masked by tongue
3: Soft palate, uvula base
4: Only hard palate seen
What is the thyromental distance?
Distance from lower border of mandible to the thyroid notch with neck fully extended.
What is the normal thyromental distance? What length indicates a difficult intubation?
6-6.5cm or 4 finger-breaths. Less than 3 fingers indicates difficult intubation.
What 3 axis are aligned in the sniffing position?
Oral, pharyngeal and laryngeal.
What is the goal of pre-oxygenation?
Increased oxygen concentration in functional reserve volume and decreased nitrogen.
How many minutes of tight face mask should be used for pre-oxygenation and how many minutes of apnea can a healthy patient tolerate after this? What is the alternative to this method and how many minutes of apnea can a patient tolerate with that method?
3-5 minutes tight face mask with 100% O2, a healthy patient can tolerate up to 10 minutes of apnea. Four vital capacity breaths in 30 seconds allows a healthy patient to tolerate up to 5 minutes of apnea.
What are the elements of an airway setup?
- Laryngoscope-2 types of blades
- Oral/nasal airways in several sizes
- Tongue depressor
- ETT 2 sizes
- Suction
- Ambu-bag
- Stylet
- LMA (difficult airway) #4
What size ETT do you generally use for adult males?
For adult females?
Males: 7.5 & 8.0
Females 6.5 & 7.0
What is the desirable position for the ETT?
What measurement on the ETT does this correlate to for males and females?
2 cm below the vocal cords and 4cm above the carina.
Males 23 cm Females 21 cm.
What sensory nerves stimulate the airway?
Glossopharyngeal, internal branch of the superior laryngeal and the recurrent laryngeal.
