Airway Devices and Adjuncts

Question 1

What are the main types of airway devices?

Answer 1

Airway adjuncts - Guedel, NPG tube

Supraglottic airways - LMA, I-gel

Endotracheal tubes

Question 2

What is the function of an oropharyngeal (Guedel) airway?

Answer 2

To restore airway patency in upper airway obstruction caused by a decreased level or consciousness in a patient.

Question 3

What are the downsides to an oropharyngeal (Guedel) airway?

Answer 3

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.

Question 4

How is a guedel airway measured?

Answer 4

9 sizes

From the patient’s incisors to the angle of the mandible

Question 5

How is a guedel airway inserted?

How does this differ in infants?

Answer 5

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.

Question 6

What is a nasopharyngeal airway (NPA) and when is it used?

Answer 6

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

Question 7

How is a nasopharyngeal (NPA) airway sized and inserted?

Answer 7

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)

Question 8

When is a nasopharyngeal (NPA) airway contrindicated?

Answer 8

Base of skull fracures and bleeding disorders.

Question 9

What can an incorrectly sized NPA cause?

Answer 9

Airway too large can result in necrosis of mucosa.

Question 10

What are the types of supraglottic airway devices (SADs)?

Answer 10

Laryngeal mask airway

I-gel

Question 11

When are supraglottic airways devices (LMAs and i-gel) commonly used?

Answer 11

Routine anaesthsia

Emergency airway management (resus trolleys)

Question 12

In what ways are endotracheal tubes more protective than SADs?

Answer 12

Supraglottic airway devices offer little/less protection against aspiration of gastric contents

Question 13

In what patients are supraglottic airways devices (SADs) contraidicated in?

Answer 13

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.

Question 14

What are the features of the laryngeal mask airway?

Answer 14

First generation SAD

Cuff at distal end to be inflated

Different sizes

Low cost and disposable

Question 15

When might the LMA be used?

Answer 15

Role as aid in difficult intubation

May not protect against aspiration in the event of regurgitation

Question 16

What features does the I-gel have - how does it differ to the LMA?

Answer 16

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.

Question 17

What is the use of an I-gel?

Answer 17

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.

Question 18

What are the features and use of an endotracheal tube?

Answer 18

Secures airway, allowing spontaneous and controlled ventilation

Radio-opaque line for visualisation on x-ray (bronchial siting)

May have cuff at tracheal end.

Question 19

How is an ETT sized?

Answer 19

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.

Question 20

What should be between the two black intubation markers on an ETT?

Answer 20

The volcal cords (a guide in most patients)

Question 21

What is a stylet?

Answer 21

Rigid device which can be used to adject the curvature of a tracheal tube to help direct it through the vocal cords.

Question 22

What is a bougie?

Answer 22

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