EENT Flashcards
Important consideration in a patient with glaucoma using echothiophate eye drops
Echothiophate - indirect-acting parasympathomimetic agent to produce miosis
- irreversible cholinesterase inhibitor –> avoid use of succinylcholine and ester LA for at least 6 weeks
Describe intraocular pressure
IOP - ~10-20mmHg
*bucking or coughing increases to ~30-40mmHg
*hypercapnia dilates choroidal vessels –> increases IOP (‘theoretically’)
Compare retrobulbar and peribulbar block
RETROBULBAR ‘
- akinesia of EOMs –> denser block
- uses less volume but quicker onset
PERIBULBAR
- easier to do (involves 1 injection around the cone –> lesser chances of intraocular & intradural injection)
think subarachnoid and epidural block regarding block and volume
*oculocardiac reflex: retrobulbar > > peribulbar
During strabismus surgery, HR suddenly drops from 70s to 30s.
Oculocardiac reflex - usually caused by traction on the EOMs, esp. MR
Afferent - trigeminal n.
Efferent - vagal n.
*cessation of manipulation usually resolves the bradycardia in a few seconds
*retrobulbar block DOES NOT inhibit the reflex
What types of EENT surgeries are associated with increased risk of PONV?
strabismus surgery, adenotonsillectomy, otoplasty, and surgeries lasting longer than 30 minutes
You have been called regarding a 4-year-old boy presenting to the ER with a high-grade fever. He is seen to be leaning forward and drooling.
Epiglottitis - clinical diagnosis
- commonly bacterial (HiB)
- presents acutely and more toxic
*Do not provoke the child
Transfer him in an upright position, preferably on parent’s lap
*Induction: inhalational induction, maintaining spontaneous respiration
- ONLY THEN insert IV and attach monitors
- use 0.5cm smaller ETT
- ensure patient is in deep anesthesia prior to laryngoscopy
*Have the surgeon be available in case of ‘E’ tracheostomy
*Postoperative ventilation and sedation to allow the swelling to subside (usually 1-2 days)
In case of an airway fire, what is the most urgent step to do?
Early warning signs: flame or flash, unusual sounds, odors, or smoke –> immediately inform the team and halt the procedure
Airway fire - involves either the ETT or the circuit
- Shut off O2 delivery i.e. disconnect circuit
- Remove the ETT (usually by the surgeon)
*pulling out the ETT without D/C O2 flow results in a blowtorch effect
According to ASA, how is a difficult airway defined?
“a conventionally trained anesthesiologist experiences difficulty with facemask ventilation of the upper airway, difficulty with tracheal intubation, or both”
According to the 2022 Difficult Airway Management Guidelines, how many attempts is the limit?
From the guideline: “A reasonable approach may be to limit attempts with any technique class (i.e., face mask, supraglottic airway, tracheal tube) to three, with one additional attempt by a clinician with higher skills”
3 + 1
How can oxygenation be optimized prior to intubation?
According to the difficult airway guideline:
- low- or high-flow nasal cannula
- head elevated throughout the procedure
What is the first question asked in the difficult airway algorithm?
Suspected difficult laryngoscopy?
What determines progression to either emergency or non-emergency pathway in the difficult airway algorithm?
Adequacy of ventilation
If yes:
* LIMIT ATTEMPTS and BE AWARE OF PASSAGE OF TIME
* INVASIVE ACCESS: surgical cricothyrotomy, needle cricothyrotomy with a pressure-regulated device, large-bore cannula cricothyrotomy, or surgical tracheostomy
Differences in the Pediatric Difficult Airway Guideline
- Transfer to tertiary center if feasible
- Ensure adequate anesthetic depth (kids are prone to bronchospasm)
During a tonsillectomy, the surgeon complains of a bloody field. What can you do?
Induce hypotension - deepen anesthesia (inhalational or propofol bolus)
*to lessen blood flow to surgical area
