Anesthesia for Ear, Nose, and Throat (ENT) Flashcards
What provides motor innervation to intrinsic muscles of the larynx
Right and Left Recurrent Laryngeal Nerves (RLN)
The Recurrent Laryngeal Nerves do NOT provide innervation to these larynx structures.
- Cricothyroid
- Inferior pharyngeal constrictor muscles
The Recurrent Laryngeal Nerves will provide sensory innervation to what structures?
- Sensory below the vocal cords
- Sensory of the upper trachea
Internal laryngeal nerve (branch of superior laryngeal nerve) will provide sensory to what structure?
Sensory above vocal cords
Presentation of unilateral injury to the RLN.
- Hoarseness from unilateral loss of vocal cord abduction occurring in conjunction with intact cricothyroid-mediated adduction
- Affected vocal cord will rest in a paramedian position
Presentation of bilateral injury to the RLN.
- Dyspnea
- Stridor
- Full airway obstruction from a bilateral vocal cord in paramedian positioning.
What intervention will be indicated in a patient with bilateral RLN damage?
Tracheostomy
What are the two branches of the Superior Laryngeal Nerve?
- External Branch
- Internal Branch
What is the external branch of the SLN responsible for?
Motor to cricothyroid muscle & inferior pharyngeal muscles
What is the internal branch of the SLN responsible for?
Sensory to laryngeal mucosa above vocal cords
What are examples of external ear surgery?
- Foreign body removal
- Removal of tumors
- Cancers
What are examples of middle ear surgery?
- Myringotomy
- Tympanoplasty
- Stapedectomy
- Mastoidectomy
Most of the middle ear surgery with the exception of myringotomy will be done under general anesthesia
What needs to be avoided for middle ear procedures?
Nitrous Oxide
What ear procedure is most commonly performed in children
Myringotomy with tube placement.
Anesthesia for Myringotomy
Sevoflurane mask anesthesia
What procedure is done to treat otosclerosis?
Stapedectomy
GETA
What are examples of inner ear surgery?
- Cochlear implant
- Surgery to Endolymphatic sac or Labyrinth
Most patients involved in ear procedures are prone to _________.
PONV
Why do you want controlled hypotension with a mastoidectomy?
To control bleeding
Anesthesia considerations for ear surgery
- Most of the time GETA
- Reinforced or RAE tube
- No N2O in middle ear surgery (risk of barotrauma)
Fick’s Law of Diffusion
Rate of diffusion of a substance across a membrane is related to concentration gradient, surface area, solubility, membrane thickness, molecular weight
- N2O is more soluble than nitrogen
- N2O diffuses into air containing cavities more rapidly than nitrogen (risk of barotrauma)
Anesthesia Consideration for Stapedectomy
- Laser precautions
- Facial nerve monitoring
- Deliberate hypotension
- PONV (use at least 3 antiemetics)
- Gentle emergence (Deep extubation?)
Identify which medications should be avoided in the anesthesia plan for a patient presenting for a tympanoplasty & mastoidectomy.
- Nitrous Oxide
- Non-depolarizing muscle blockers depending on facial nerve monitoring
What preop assessments are focused on nasal procedures?
- OSA
- HTN
- Samter Triad
Samter Triad = Nasal polyps , Asthma, Sensitivity to ASA/NSAIDS
What is the Samter Triad. What is the significance?
- Nasal polyps
- Asthma
- Sensitivity to ASA/NSAIDS
The combination of these three factors may produce DEADLY bronchospasms
How long should ASA and NSAIDs be held before nasal surgery?
1 – 2 weeks preop
What is the purpose of a throat pack for nasal surgery?
Prevents blood & surgical debris in pharynx & larynx
Document throat pack time in & out
What are the three vasoconstrictors used in nasal surgery?
- Cocaine 4%
- Phenylephrine
- Oxymetazoline (Afrin)
What is the MOA of Cocaine 4%?
What is the dose?
- Blocks reuptake of norepinephrine at sympathetic nerve terminals
- Do not exceed 1.5 mg/kg
Contraindication of Cocaine 4%
- CAD
- HTN
- Pt on MAOIs
Dose of Phenylephrine used for nasal procedures
- Solo or w/lidocaine
- Initial dose < 500 mcg
Treat HTN with direct vasodilators or α-receptor antagonists
What drugs should be avoided if phenylephrine is used for nasal surgery?
β-adrenergic blocker and CCB should be avoided because they may worsen CO and produce pulmonary edema
MOA of Oxymetazoline.
Dose.
- Selective α1-agonist and partial α2-agonist imidazoline-derivative
- 0.05% solution x 3 sprays
Contraindication of Oxymetazoline
Patients taking monoamine oxidase inhibitors
Emergence Consideration for Nasal Surgery
- Gastric suctioning before emergence
- Prevent coughing / bucking (↑ bleeding)
- Avoid pressure on face (lift that jaw up to the mask)
What are examples of Endoscopic Sinus Surgeries?
- Nasal polyposis
- Sinusitis
- Epistaxis control
- Tumor excision
- Foreign body removal
Anesthesia Considerations for Endoscopic Sinus Surgery
- Controlled hypotension (blood free field)
- TIVA (Propofol / remifentanil)
- Smooth wake-up
- SGA vs ETT (oral rae)
- Nasal Vasoconstriction meds
How will the patient be positioned if undergoing an image-guided endoscopic sinus surgery?
A special headset on the patient requires the bed to be turned 180 degrees away from the anesthesia provider.
Potential Complications for Endoscopic Sinus Surgery
- Orbital hematoma
- Blindness from orbital trauma
- Optic nerve injury
- CSF leak
- Carotid or ethmoid artery invasion
- Cranial cavity entry
- Hemorrhage
When will a patient have a Tonsillectomy performed?
- Tonsillar hyperplasia
- Recurrent tonsillitis
- Malignancy
When will a patient have an Adenoidectomy performed?
Hyperplasia causing nasopharyngeal obstruction
Lymphoid tissue posterior to the nasal cavity in the roof of the nasopharynx
Adenoids
When pre-oping for a Tonsillectomy/Adenoidectomy, if the patient has OSA. What other associated issues would the anesthesia provider investigate?
- Cor pulmonale
- Pulmonary HTN
- RV hypertrophy
- Cardiomegaly
Tonsillectomy/Adenoidectomy Anesthesia Considerations
- Oral RAE ETT or wire-reinforced ETT
- Stimulating procedure
- Consider remifentanil
- PONV
- Gastric suctioning before emergence
- Post-op PAIN!!!!
- Tonsillar local anesthetic injection
- Morphine/hydromorphone
- Avoid NSAIDs (risk of bleeding)
Tonsillectomy/Adenoidectomy complications
- Post-op hemorrhage
- Usually occurs within 6 hours
- May occur days later
Patients with nasal polyps, asthma, and sensitivity to aspirin or at risk for ________ during their procedure.
Bronchospasm
OSA Surgery Anesthesia Considerations
- Possible difficult ventilation & intubation
- Oral RAE tube – taped midline
- Redundant tissue, macroglossia
- Minimize opioids
- Postop hypoxia
- Dexamethasone to reduce airway edema (10 mg)
Patients with OSA have an increase in postoperative obstructive episodes, peaking on postoperative day ____ and returning to preoperative levels after a week
Day 3
A panendoscopy is a combination of what three procedures?
- Laryngoscopy
- Bronchoscopy
- Esophagoscopy
Anesthesia Considerations for Panendoscopy
- Anterior commissure laryngoscope is very stimulating
- Consider potent/short-acting opioid (REMIFENTANIL)
- Microlaser/ laser ETT
- Transtracheal jet ventilation (TIVA)
- Tracheostomy may be warranted
- Throat pack
- Head extended, neck flexed
- Need shoulder roll and donut
- GETA w/ muscle relaxant
- Avoid N2O and keep FiO2 low
What are the pros of using Microlaser/ Laser Tubes?
- All metal ETT
- Airway protection
- Ventilation control
- EtCO2 measurement
- Double cuff
What are the cons of using Microlaser/ Laser Tubes?
- Higher than usual ventilation pressures (narrow diameter)
- Challenging surgical access
- Tube ignition is possible when the laser is in use
Decribe how an anesthesia provider performs supraglottic jet ventilation.
- High-pressure O2 “breaths” @ 20 – 50 PSI
- 1 second on / 3 seconds off
Type of sedation required for jet ventilation
TIVA
Disadvantages of Jet Ventilation
- Barotrauma possible (PSI >50)
- No measurement of Vt or EtCO2
- Suboptimal for obese pts
Signs and symptoms of thyrotoxicosis
- Sinus tachycardia / A-fib
- MI / CHF
- Nervousness/tremulousness
- Insomnia
- Heat intolerance
- Weight loss
Anesthesia considers if a patient has a goiter.
- Deviation of larynx
- Tracheal compression causing airway stenosis
- Airway collapse after induction of anesthesia & muscle relaxant administration
- Horner syndrome
- SVC obstruction
How is hypercalcemia secondary to hyperparathyroidism treated in pre-op?
- Fluids
- Furosemide
- Bisphosphonates
Parathyroidectomy Lab considerations
- Baseline Ca++ & PTH
- Redraw Ca++ & PTH 10 minutes after excision of parathyroid
- Consider an arterial line
Thyroidectomy & Parathyroidectomy Anesthesia Considerations
- Intubation using NIM ETT, allows for identification of recurrent laryngeal & vagus nerves
- Avoid long-acting muscle relaxants
- Shoulder roll
- Avoid coughing/bucking
- Consider deep extubation
Between what tracheal rings will a tracheostomy be performed?
B/w 2nd and 3rd tracheal ring
Tracheostomy Anesthesia Considerations
- If Cautery is used → low FiO2 (under 30% O2)
- If using scalpel → higher FiO2 acceptable
- Risk of false passage creation with Shiley trach
- Have 6.0 mm ID reinforced ETT available
- Shoulder roll
When will a neck dissection & laryngectomy be performed?
Prevention/treatment of head & neck CA
Anesthesia considerations for neck dissection & laryngectomy
- 2 large bore IVs
- Arterial line
- Nerve integrity monitoring (NIM) during neck dissection
- Minimize fluid administration
- Free flap (avoid neo and levo) → graft ischemia
What are Le Fort Fractures?
How many types are there?
- Midfacial fractures
- 3 major types (I, II, and III)
Describe a Le Fort I fracture
- Horizontal fx involving inferior nasal aperture
- Separates teeth and lower maxillary components from upper facial structures
Describe a Le Fort II fracture
Triangular fracture with the fracture line across the nose,
below the infraorbital rim and through the entire lower maxilla
Describe a Le Fort III fracture
- Fx that parallels the base of the skull
- Fx of nasal, orbital, zygoma
- Mobile maxilla (occlude airway)
- Fx cribriform plate may separate nasopharynx and base
- Not common
- Needs fiberoptic intubation
Anesthesia Considerations for Le Fort fractures
- Rule out head /neck injury
- Neuro injury?
- C-spine precautions?
- Possible chest trauma
- Full stomach
- Bloody airway obstructing view
- Limited ROM (in line stabilization)
When will a patient have a Le Fort Osteotomy?
- Correct maxillary deformities
- Corrects malocclusion of teeth by movement of maxilla and/or mandible
Anesthesia Considerations for Le Fort Osteotomy?
- Young patients (< 30 yo)
- Nasal intubation
- Deliberate hypotension
- Minimal fluid resuscitation
- Opioids / multimodal PONV prophylaxis
- Awake extubation
- Jaws wired or tightly banded
Interventions for Allergic Reaction Angioedema
- Antihistamines
- Steroids
- H2 antagonist
- Epinephrine
- Intubation (use a smaller tube)
At what age is acute epiglottis most common?
2 to 6 years old
Cause of acute epiglottis
H-influenza
Signs and Symptoms of Acute Epiglottis
- Sore throat
- Dysphagia
- Drooling
- Fever
- Muffled voice
- Open-mouth tripod position
- Stridor / respiratory distress
- Total airway obstruction
Pediatric Management of Acute Epiglottis
- Prevent crying
- Calm inhalation anesthesia induction
- Maintain spontaneous respiration
- Consider smaller ETT
- Rigid bronchoscopy
- Surgical airway may be necessary
Adult Management of Acute Epiglottis
- Assessment of disease
- Oropharyngeal exam
- Fiberoptic nasopharyngoscopy
- ICU admission
- Inhaled mist medication/ steroids/ abx
- Awake fiberoptic intubation (safetest option)
What is Ludwig Angina
- Floor of mouth infection
- Starts with mandibular molars
- Spreads to submandibular, sublingual, submental, and buccal spaces
- Tongue displaced posteriorly
What are the risks involved with Ludwig Angina?
- Airway occlusion in supine position
- Risk of abscess rupture
What is Ludwig Angina associated with?
Trismus
Trismus refers to muscle spasms in your temporomandibular joint.
Airway management of Ludwig Angina
- Dependent on severity, CT/MRI findings, and surgical preferences
- Elective tracheostomy for an I & D
- Nasal fiberoptic intubation
What are the symptoms of laryngeal trauma?
- Abrasions
- Discoloration
- Indentation
- Pain in larynx region
- Dyspnea / Dysphagia / Dysphonia
- Hoarseness / Stridor
- Hemoptysis
- Subq emphysema
Laryngeal Trauma Anesthesia Considerations
- Avoid cricoid pressure d/t risk of crico-tracheal separation
- Airway Dependent on the severity of symptoms
- Tracheostomy may be the best option to secure the airway
- If Subq emphysema is present avoid mask ventilation, just RSI them
What is the triad to operation room fire
- Fuel
- Oxidizer
- Ignition Source
What can be a source of fuel in the OR?
- Alcohol skin preps
- Drapes/ gowns
- Gauze, sponges
- Hair/ skin
- ETT, N/C
- Intestinal Gases
What can be ignitions in the OR?
- Bovie
- Fiberoptic light source
- Drills
- Defibrillators
What can be oxidizers in the OR?
- O2
- N2O
Prevention of Airway Fire during an ENT procedure
- Maintain O2 ≤ 30% using O2 / air
- Avoid N2O
- Use laser safe ETT / use dye & NS in cuff
- Have 50 mL NS syringe readily available to extinguish fire
- Have 2nd ETT available to reintubate in case of fire
- Inform surgical team if high FiO2 required
Management of Airway Fire
- STOP procedure & call for HELP!!
- Remove burning ETT & place in H2O
- Stop ventilation
- Discontinue O2 & N2O (if used)
- Remove sponges & other flammable material from airway
- Pour saline in airway
- Use CO2 fire extinguisher
Management of Post Airway Fire
- Re-establish ventilation
- Avoid oxidizer-enriched environment if possible
- Examine ETT for potential fragments retained in airway
- Consider bronchoscopy
Management of Non-Airway Fire
- Stop flow of airway gases
- Remove drapes & all burning/flammable materials
- Extinguish burning materials with saline
- Use CO2 fire extinguisher if needed
Management of Post Non-Airway Fire
- Maintain ventilation
- Assess for inhalation injury if patient not intubated
- Assess for burns
The procedure used in patients with head and neck cancer to search for vocal cord lesions, obtain tissue biopsies, and monitor for tumor recurrence.
Panendoscopy
