Lecture 5 8/28/24 Flashcards
Why is airway management an important component of anesthesia?
-pharmacology and/or disease affects patient homeostasis
-different patients present with various challenges
-ability to protect airway is lost under anesthesia
-airway management is required for administration of inhalant anesthetics with simultaneous oxygen
What are the landmarks within the airway when performing intubation?
-arytenoid cartilages
-glottis
-vocal folds
-epiglottis
What is the preferred method of laryngeal visualization in small animals?
laryngoscopy
What are the two types of laryngoscope blades most commonly used in veterinary medicine?
-miller: primarily straight with a curve at the end
-macintosh: curved throughout entire blade
What are the two components of a laryngoscope?
-blade with light bulb
-handle with power source
What is the purpose of the murphy eye on a murphy ET tube?
prevents complete occlusion of the tube in the event that the open end of the tube becomes occluded
What are the two most common ET tube materials and their characteristics?
-PVC: rigid curvature, easier to handle
-silicone: softer and more compliant, easier on trachea
What are the components of the ET tube?
-patient end with murphy eye
-cuff
-outer diameter marking
-internal diameter marking
-depth markings
-machine connector
-pilot balloon with spring valve
What are the two cuff types and their characteristics?
-low pressure, high volume: accepts larger volume of air that is dispersed over greater tracheal area; less damaging to mucosa
-high pressure, low volume: accepts lower volume of air that is dispersed over lesser tracheal area; more damaging to mucosa if used incorrectly
What considerations must be taken into account when selecting an ET tube?
-species
-patient size
-tracheal diameter
-special circumstances/procedures
What is the optimal tracheal tube?
-widest without trauma
-shortest but placed appropriately
Why is ET tube width important?
want a wide enough tube that the work of breathing is reduced while preventing scraping of the mucosa
Why is ET tube length important?
want a tube long enough that it cannot pop out, while short enough that the dead space and work required to breathe is reduced
What steps should be taken when preparing to intubate?
-have all supplies ready
-leak check cuffs
-ensure clean or sterile ETT
-pre-measure ETT depth against patient with a different tube than the one being used
-ensure machine connector is present
-lubricate tube over cuff only
How should the ET tube be handled and placed?
-tube in dominant hand
-laryngoscope in non-dominant hand
-tube inserted between arytenoid cartilages and slid into trachea
-should not have resistance
Once the ET tube is placed, what steps should occur?
-attach to oxygen source and provide patient with breaths
-confirm tube placement
-ensure tube is no deeper than thoracic inlet
-tie tube into place at appropriate depth
How can ET tube placement be confirmed?
-capnograph/measuring CO2 output (ideal method)
-palpation
-visualization
-condensation/airflow
How is an ET tube leak check performed following intubation?
-connect tube to breathing circuit
-provide positive pressure breath, holding at 15-20 cmH2O
-place ear near patient mouth opening and listen for audible leak during breath
-inflate pilot balloon until audible leak is just absent during positive pressure
-record volume added to pilot balloon
Why is lidocaine commonly used during intubation in cats?
to mitigate laryngospasm
When is nasotracheal intubation used?
When oral access in needed and an ET tube would be in the way
What is retrograde intubation?
insertion of a needle and guide wire into the trachea through the neck; guide wire is then used to guide ET tube into trachea
What precautions should be taken when intubating brachycephalic patients?
-pre-oxygenate to provide more time for intubation
-have smaller tubes available
-have a back up plan for providing oxygen
What considerations should be taken during extubation?
-patient should have regained control of the airway
-deflate cuff
-gently remove from oral cavity
-monitor patient for regained control of breathing
-supplement oxygen if needed
