Intubation Flashcards
Endotracheal tubes are
Flexible tube placed in the trachea
Delivers anesthetic gases or oxygen directly from the anesthetic machine to the lungs
Types of ET tubes
Murphy tubes
Cole tubes
Characteristics of cole tubes
No side hole or cuff
Abrupt decrese in diameter of tube
Used in birds and reptiles
Characteristics of murphy tubes
Beveled end and side holes
Possible cuff
Materials for et tubes
Polyvinyl chloride: clear and stiffer
* Red rubber: flexible and less traumatic, absorbent, and may kink or collapse
* Silicone: pliable, strong, less irritating, resist collapse
Length of ET tubes
Standard lengths
* Scale marks distance from patient end (centimeters)
Size of ET tubes are measured by
- Measured by internal diameter (ID)
- Range from 1 mm to 30 mm
Parts of the ET tube
Valve with syringe attached
Pilot balloon
Machine end
Connector
Tie
Measurement of length from patient end (cm)
Measurement of internal diameter (mm)
Inflated cuff
Patient end
Murphy eye
Laryngescope
Used to increase the visibility of the larynx while placing an ET tube
Parts
* Handle containing batteries
* Blade to depress tongue
* Light source to illuminate the throat
Sizes
* Small animal 0 to 5; large animal up to 18-inch blade
Types
* Miller blades
* Macintosh blade
Why are ET tubes placed
Endotracheal tube is placed in the patient’s airway after general anesthesia induction or during respiratory arrest
* Conducts air or anesthetic gases directly from oral cavity to trachea
* Bypasses the nasal passages, oral cavity, pharynx, and larynx
* This limits dead space
* Can be connected to an anesthetic machine to maintain anesthesia or to an ambu bag for ventilation during cardiac arrest
Benefits of endotracheal intubation
Helps maintain an open airway
* Leave in place until the swallowing reflex returns
* With inflated cuff helps prevent aspiration of vomitus, blood, saliva
* Reduces anatomic dead space
* Improved efficiency of gas exchange
* Decreased exposure of personnel to waste gas
* Ventilation can be supported manually or mechanically
* Especially useful for patients in cardiac or respiratory arrest
Equipment for endotracheal intubation
Three endotracheal tubes of slightly different diameters
Lube for lubricating tube
Two-foot lengths of IV tubing or rolled gauze to secure tube
Gauze sponge to grasp tongue
10-mL slip tip syringe to inflate cuff
Good light source
Stylet for narrow diameter tubes
Lidocaine injectable solution, spray, or gel to control laryngospasm (cats)
Laryngoscope with appropriate blade
How to chose the ET by diameter
Small enough to not cause trachea injury
* Large enough to provide a seal with inflated cuff
* Palpate the trachea to determine size
* Can use patient weight as a guideline
How to chose ET length
minimize mechanical dead space
* Must reach the thoracic inlet
* Not extend 2 cm beyond the end of the muzzle
Intubation procedure
*Know the anatomy of the throat
* Pharynx and larynx
*Know the proper restraint and positioning techniques
* Don’t attempt intubation unless you can visualize the larynx
*Have proper lighting
*Induce patient with IV anesthetic
* Unconsciousness, no voluntary movement, no pedal reflex, sufficient muscle relaxation, no swallowing when tongue is pulled
Steps to intubation
1.Gather all necessary equipment
2. Restrain patient in sternal recumbency with head extended and neck straight
3. The tongue is pulled forward and slightly downward
4. Use the laryngoscope to illuminate the larynx
5. Gently insert tube rapidly and correctly, giving it a small rotation as it is inserted
a. Never force the tube
b. When placed the curve of the tube should match the
curve of the neck
6. Roll patient into lateral recumbency
7. Ensure proper placement
8. Secure the tube and inflate the cuff
9. Turn on the oxygen
10. Attach the breathing circuit
11. Turn on the anesthetic vaporizer if required
12. Begin patient monitoring
How to check for proper tube placement
Palpate the neck
Re-visualize larynx and confirm the tube is in the correct location
Watch reservoir bag as animal breathes
Feel for air movement from the tube connector as patient exhales
Fogging of the tube during exhalation
Unidirectional valve motion
Patient coughs during intubation
Ability of patient to vocalize indicates misplaced tube
Laryngospasm is and common ins
- Reflex closure of the glottis in response to contact with an object or substance
- Common in cats, swine, and small ruminants in light plane of anesthesia
- Makes intubation very difficult; larynx is easily damaged
- May lead to cyanosis or hypoxemia
- Not usually a problem with cardiac arrest
Prevention of laryngospasm
- 2% injectable lidocaine or lidocaine gel
- Most commonly a lidocaine spray
- Adequate depth of anesthesia
- Wait for glottis to open before intubating
- Don’t force the tube
How to secure the tube and inflate the cuff
- Tie the ET tube securely without compressing the tube
- Tie around muzzle, or behind head
- Cuff the tube
- Extend the patient’s head
- Have an assistant close the pop-off valve and compress the reservoir bag
- Listen for gas leaks
- Inflate the cuff until the leaking just ceases at a pressure of 20 cm H2O
- OPEN THE POP-OFF VALVE
How to do extubation
- Prepare by untying gauze and syringe ready to deflate cuff
- Deflate cuff
- Remove when:
- Dogs –> Swallowing reflex returns
- Cats –>Ear twitches in response to stimulus
- When signs of impending arousal are present (voluntary limb, tail, or head movements)
- Remove the tube in one slow, steady motion
Complications of intubation
- Vagus nerve stimulation
- Brachycephalic dogs or other breed deformities
- Overzealous intubation efforts
- Over inflation of cuff
- Obstructed endotracheal tube
- Waiting too long to remove the tube
- Improper cleaning and sanitizing between uses
- Tracheal and/or laryngeal irritation leading to postsurgical cough
- Very common!
Supraglottic airway device
V-gels®; these are species specific
◦ Rabbit and cat
◦ Working on canine
Trauma-free high quality pressure seal around the airway and oesophageal structures.
V-gel® is shaped to mirror the pharyngeal airway anatomical structures for each species of animal.
Benefits of V-gel
Fast, easy, safe, and stress-free device insertions.
No post-operative coughing or gagging.
Low airway breathing resistance due to the large airway channel within the device.
High quality pressure seal restricting leakage of volatile anaesthetic agents
◦ Improving health and safety in anaesthesia and overcoming patient sensitivity to smell – a common problem in rabbits.
Super soft contoured tip for a highly effective upper oesophagus seal.
◦ Prevents potential aspiration of reflux fluid.
Integral gas sampling port to reduce re-breathing dead-space.
◦ Makes high quality monitoring easier.
Integral bite block to stop patient damaging device and occluding the airway.
Materials safe for autoclave sterilization.
