Lecture 5 8/28/24

Question 1

Why is airway management an important component of anesthesia?

Answer 1

-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

Question 2

What are the landmarks within the airway when performing intubation?

Answer 2

-arytenoid cartilages
-glottis
-vocal folds
-epiglottis

Question 3

What is the preferred method of laryngeal visualization in small animals?

Answer 3

laryngoscopy

Question 4

What are the two types of laryngoscope blades most commonly used in veterinary medicine?

Answer 4

-miller: primarily straight with a curve at the end
-macintosh: curved throughout entire blade

Question 5

What are the two components of a laryngoscope?

Answer 5

-blade with light bulb
-handle with power source

Question 6

What is the purpose of the murphy eye on a murphy ET tube?

Answer 6

prevents complete occlusion of the tube in the event that the open end of the tube becomes occluded

Question 7

What are the two most common ET tube materials and their characteristics?

Answer 7

-PVC: rigid curvature, easier to handle
-silicone: softer and more compliant, easier on trachea

Question 8

What are the components of the ET tube?

Answer 8

-patient end with murphy eye
-cuff
-outer diameter marking
-internal diameter marking
-depth markings
-machine connector
-pilot balloon with spring valve

Question 9

What are the two cuff types and their characteristics?

Answer 9

-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

Question 10

What considerations must be taken into account when selecting an ET tube?

Answer 10

-species
-patient size
-tracheal diameter
-special circumstances/procedures

Question 11

What is the optimal tracheal tube?

Answer 11

-widest without trauma
-shortest but placed appropriately

Question 12

Why is ET tube width important?

Answer 12

want a wide enough tube that the work of breathing is reduced while preventing scraping of the mucosa

Question 13

Why is ET tube length important?

Answer 13

want a tube long enough that it cannot pop out, while short enough that the dead space and work required to breathe is reduced

Question 14

What steps should be taken when preparing to intubate?

Answer 14

-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

Question 15

How should the ET tube be handled and placed?

Answer 15

-tube in dominant hand
-laryngoscope in non-dominant hand
-tube inserted between arytenoid cartilages and slid into trachea
-should not have resistance

Question 16

Once the ET tube is placed, what steps should occur?

Answer 16

-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

Question 17

How can ET tube placement be confirmed?

Answer 17

-capnograph/measuring CO2 output (ideal method)
-palpation
-visualization
-condensation/airflow

Question 18

How is an ET tube leak check performed following intubation?

Answer 18

-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

Question 19

Why is lidocaine commonly used during intubation in cats?

Answer 19

to mitigate laryngospasm

Question 20

When is nasotracheal intubation used?

Answer 20

When oral access in needed and an ET tube would be in the way

Question 21

What is retrograde intubation?

Answer 21

insertion of a needle and guide wire into the trachea through the neck; guide wire is then used to guide ET tube into trachea

Question 22

What precautions should be taken when intubating brachycephalic patients?

Answer 22

-pre-oxygenate to provide more time for intubation
-have smaller tubes available
-have a back up plan for providing oxygen

Question 23

What considerations should be taken during extubation?

Answer 23

-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