Anesthesia for ENT and Maxillofacial Surgery Flashcards
What is the Larynx?
The larynx is a rigid organ composed of three paired and three unpaired cartilages (arytenoid, corniculate, and cuneiform; and thyroid, cricoid, and epiglottis, respectively) and is supported by the hyoid bone.
Name the following
- Cricothyroid ligament
- Thyroid Cartilage
- Cricoid cartilage
- Epiglottis
5 Corniculate Cartilage
6.Arytenoid Cartilage
Mention the paired cartilage of the larynx
arytenoid
corniculate
cuneiform
Mention the unpaired cartilages of the larynx
Epligottis
Thyroid
Cricoid
Mention the Intrinsic muscle of the larynx
Cricothyroid
Thyroarytenoid
Vocalis
Posterior Cricoarythenoid
Lateral Cricoarytenoid
Transverse Arytenoid
Aryepiglottic
Oblique Arytenoid
Which muscle tension and elongates the vocal cords?
The cricothyroid muscle
Which muscle relaxes the vocal cords?
The thyroarytenoid muscle and the vocalis muscle
Which muscle abducts the vocal cords?
the posterior cricoarytenoid muscle
Which muscle adducts the vocal cords?
the lateral cricoarytenoid and the transverse arytenoid
Which muscle closes the glottis?
the aryepiglottic and the oblique arytenoid*
Which muscle closes the glottis and approximates the folds?
the oblique arytenoid muscle
Which muscles of the larynx are innervated by the recurrent laryngeal nerve?
All the muscles of the larynx are innervated by the recurrent laryngeal nerve except for the cricothyroid muscle
The crycorthyroid muscle is innervated by
the superior laryngeal nerve
Mention the extrinsic muscles of the larynx
sternohyoid
sternothyroid
thyrohyoid
thyroepiglottic
stylopharyngeus
inferior pharyngeal constrictor
What is the function of the sternohyoid muscle? Innervation?
Draws the hyoid bone inferiorly
Innervated by Cervical plexus, C1,C2,C3
What is the function of the sternothyroid muscle? Innervation?
Draws the thyroid cartilage caudad
Innervated by Cervical plexus, C1,C2,C3
What is the function of the thyrohyoid muscle? Innervation?
pulls the hyoid bone inferiorly
Innervated by cervical plexus, hypoglossal nerve and c1 and c2
What is the function of the thyroepiglottic muscle? Innervation?
Inversion of aryepliglottic fold
Innervated by RLN
What is the function of the stylopharyngeus? Innervation?
folds the thyroid cartilage
Innervated by glossopharyngeal nerve
What is the function of the inferior pharyngeal constrictor? Innervation?
aids swallowing
Innervated by pharyngeal plexus and vagus nerve
Why anticholinergic drugs are used during ENT procedures?
Anticholinergic drugs are used for their antisialagogue effect as its useful in certain intraoral procedures that require a drier operative field
Basically to decrease secretion
Which anticholinergic drug is best to use during an ENT procedure?
Glycopyrrolate as it produces less tachycardia in comparison with atropine
Also, Glycopyrrolate does not cross the blood-brain barrier and thus lacks of sedative effects
Important facts about Cocaine when used as a topical drug
concentration 4%
Dose 3mg/kg
Only anesthetic with vasoconstrictive ability
Blocks reuptake of norepi and epi at adrenergic nerve endings
Important facts about Benzocaine
Used for endoscopy
Short DOA (10 min)
Can produce METHOHEMOGLOBINEMIA
Bupivacaine Notable features
slow hepatic clearance long DOA
Dyclonine notable features
Topical spray or gargles
frequent use for laryngoscopy
absorbed through skin and mucous membrane
Hypotension technique: What are the disadvantages of sodium nitroprusside?
Reflex tachycardia
rebound hypertension
pulmonary shunting
possible cyanide toxicity
Hypotension technique: What are the disadvantages of dexmedetomidine?
Bradycardia, hypotension most often seen with bolus, heart block
Hypotension technique: What are the disadvantages of Nitroglycerin?
Increases intracranial pressure, highly variable dose requirements
Hypotension technique: What are the advantages of nicardipine?
preserves cerebral blood flow
Hypotension technique: What are the disadvantages of remifentanil with propofol?
No analgesic effect once remifentanil infusion is discontinued, post-operative secondary hyperanalgesia