Airway Devices and Adjuncts Flashcards
What are the main types of airway devices?
Airway adjuncts - Guedel, NPG tube
Supraglottic airways - LMA, I-gel
Endotracheal tubes
What is the function of an oropharyngeal (Guedel) airway?
To restore airway patency in upper airway obstruction caused by a decreased level or consciousness in a patient.
What are the downsides to an oropharyngeal (Guedel) airway?
Can induce gag reflex or laryngospasm (if consious or semi-conscious)
No protection against aspiration
No appropriate in some facial injuries
Most common caused of damage to teeth in anaesthetised patients - when biting down.
How is a guedel airway measured?
9 sizes
From the patient’s incisors to the angle of the mandible
How is a guedel airway inserted?
How does this differ in infants?
Insert upside down and rotate 180 degrees.
In infants insert right way round using a tongue depression, minimising the risk of trauma to the oropharyngeal mucosa.
What is a nasopharyngeal airway (NPA) and when is it used?
Soft plastic tube, left-facing bevel.
Better tolerated in semi-conscious and awake patients - won’t cause laryngospasm
Useful in patients with limited mouth opening
How is a nasopharyngeal (NPA) airway sized and inserted?
Lubricated and instered gently into either nare (too much force can create false passage)
Sized approximately the same length as the patients little finger (usually female 6 and male 7)
When is a nasopharyngeal (NPA) airway contrindicated?
Base of skull fracures and bleeding disorders.
What can an incorrectly sized NPA cause?
Airway too large can result in necrosis of mucosa.
What are the types of supraglottic airway devices (SADs)?
Laryngeal mask airway
I-gel
When are supraglottic airways devices (LMAs and i-gel) commonly used?
Routine anaesthsia
Emergency airway management (resus trolleys)
In what ways are endotracheal tubes more protective than SADs?
Supraglottic airway devices offer little/less protection against aspiration of gastric contents
In what patients are supraglottic airways devices (SADs) contraidicated in?
Patients with full stomaches or those prone to reflux
Offer no protection against gastric contects aspiration
Will cause airway reflexes so require topical or general anaesthetsia.
What are the features of the laryngeal mask airway?
First generation SAD
Cuff at distal end to be inflated
Different sizes
Low cost and disposable
When might the LMA be used?
Role as aid in difficult intubation
May not protect against aspiration in the event of regurgitation
What features does the I-gel have - how does it differ to the LMA?
2nd Generation SAD
Single use, cuffless, size guided
Two separate ventilation and gastric channels to reduce the risk of aspiration of gastric contents - can pass gastric tube or direct suction.
What is the use of an I-gel?
Role as an aid in difficult intubation - where ET airway not possible.
Not intended to be used for more than 4 hours
Some reduced gastric risk but not 100% and not for long operations.
What are the features and use of an endotracheal tube?
Secures airway, allowing spontaneous and controlled ventilation
Radio-opaque line for visualisation on x-ray (bronchial siting)
May have cuff at tracheal end.
How is an ETT sized?
Avarage male - 8
Avarage female -7
Paediatric - (Age in years/4) + 4
Paediatric length - (Age in years/2) + 12cm
Can be cut to length - if too long can be kinking and blocking.
What should be between the two black intubation markers on an ETT?
The volcal cords (a guide in most patients)
What is a stylet?
Rigid device which can be used to adject the curvature of a tracheal tube to help direct it through the vocal cords.
What is a bougie?
An adjunt for difficult intubation
Inserted into the trachea through the vocal cords, is then held in place whilst the ETT tube is threaded over it into the trachea
