What muscle abducts the vocal cords? - Answers- posterior cricoarytenoid
What is the only muscle that tenses (elongates) the vocal cords? - Answers-
cricothyroid "cords tense"
What muscle opens the glottis? - Answers- thyroepiglottic
What two muscles close the glottis? - Answers- aryepiglottic
oblique arytenoid
Recurrent laryngeal innervates... - Answers- below vocal cords --> the trachea
Branches off vagus in thorax
Motor: all intrinsic except cricothyroid
Glossopharyngeal innervates... - Answers- the vallecula
topside of epiglottis
soft palate
oropharynx
post 1/3 of tongue
tonsils
*afferent limb of gag reflex*
CN IX - sensory
Superior laryngeal innervates... - Answers- posterior epiglottis --> vocal cords
Internal branch is sensory - underside of epiglottis
External branch is motor - cricothyroid muscle
Superior laryngeal nerve block: - Answers- 3ml at the inferior aspect of the greater
cornu of hyoid bone bilaterally
- helps tolerate FO intubation once past the oropharynx
Glossopharyngeal block: - Answers- 1-2 ml at the tonsillar pillar bilaterally
Transtracheal block: - Answers- 3-5 ml through the cricothyroid membrane
,What is most likely to injure the left RLN while sparing the right RLN? - Answers- Mitral
stenosis (LA enlargement compresses the nerve and may present as hoarseness)
PDA ligation
Aortic arch aneurysm
Thoracic tumor
Causes of left OR right RLN injury: - Answers- parathyroid or thyroid surgery
external pressure from LMA/ETT
neck tumor
neck extension
What muscles adduct the vocal cords and arytenoids?
- there are two - Answers- lateral cricoarytenoid
transverse arytenoid
What muscle shortens the vocal cords? (relaxes?)
- there are two - Answers- thyroarytenoid "they relax"
vocalis
The cricothyroid muscle is innervated by? - Answers- external branch of SLN
- the only branch that tenses (elongates) the VCs
The internal branch of the SLN is purely?
- sensory or motor? - Answers- sensory
Where does the right RLN loop?
left RLN loop? - Answers- under the right subclavian artery
- left under the aorta (more susceptible to injury)
For the patient in sitting position, order the cartilages from superior to inferior:
cricoid
epiglottis
arytenoid
corniculate - Answers- epiglottis
corniculate
arytenoid
cricoid
How many unpaired cartilages present in the larynx?
Paired? - Answers- 3 unpaired
3 paired
9 cartilages total
Where is the adult larynx located?
Infant larynx? - Answers- C3-C6
Infant is C2-C4
,What is the narrowest part of the airway? adult/infant - Answers- Vocal cords for adult
Cricoid for infant, if paralyzed = vocal cords
Risk factors for intraoperative laryngospasm? - Answers- GERD
Exposure to 2nd hand smoke
recent URI
Age < 1 year
HYPOcapnia
light anesthesia
saliva or blood in the upper airway
What is the definition of laryngospasm? - Answers- Sustained and involuntary
contraction of the vocal cord Adductors that result in the inability to ventilate.
Tensor palatine opens? - Answers- nasopharynx
Genioglossus opens? - Answers- the oropharynx
Hyoid muscles open? - Answers- the hypopharynx
Landmarks for the Larson's maneuver? - Answers- posterior: mastoid process
superior: skull base
Anterior: ramus of mandible
Muller's maneuver? - Answers- inhaling against a closed glottis
Which type of pneumocystis produce surfactant? - Answers- type 2
Three types of pneumocytes? - Answers- type 1 - 3
type 1 - cover 80% of alveolar surface
type 3 - macrophages that fight lung infection
Most common etiology of hypoxemia in the PACU? - Answers- V/Q mismatch:
specifically atelectasis
Result as FRC becomes smaller and there is less radial traction to hold the airways
open: - Answers- result is atelectasis, R -> L shunt, and hypoxemia
Intrapleural pressure becomes positive during: - Answers- The ONLY time intrapleural
pressure becomes positive is during forced exhalation, and pneumothorax
What is transpulmonary pressure? - Answers- alveolar pressure - intrapleural pressure
- always positive, keeps airway open
- Intrapleural always negative - keeps lungs inflated
, What muscles provide the most significant contribution to forced exhalation? - Answers-
rectus abdominus
Contraction of the inspiratory muscles reduces thoracic pressure and increases thoracic
volume, what law is this? - Answers- boyles law
What muscles contract during inspiration? - Answers- diaphragm and external
intercostals (tidal breathing)
accessory muscles: sternocleidomastoid and scalenes
Muscles of exhalation? - Answers- active exhalation: abdominal muscles
internal intercostals serve as secondary role in active
The best ventilated alveoli are the? - Answers- most compliant!
- exchange more gas, volumes change more.
these alveoli reside at the steep slope of the curve
The least ventilated alveoli are the? - Answers- least compliant!
- exchange less gas, volumes change very little
reside near the top of the curve
Dead space is... - Answers- ventilation without perfusion
Shunt is... - Answers- perfusion without ventilation
Perfusion is what L/min?
Ventilation? - Answers- perfusion = 5L/min (greatest at lung base - gravity)
ventilation = 4L/min (greatest at base - higher compliance)
Compared to spontaneous ventilation, what happens to the Vd/Vt ratio when a patient is
placed on a ventilator? - Answers- The ratio increases.
What does the Vd/Vt ratio mean? - Answers- fraction of the tidal volume lost to dead
space
- gas not involved in alveolar gas exchange
Mechanical ventilation increases what west zone? - Answers- 1
- increases alveolar pressure and this increases ventilation relative to perfusion.
Increases to 0.5 or 50%
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller GEEKA. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $12.99. You're not tied to anything after your purchase.