9
EN
7.3.1. Placement Technique
Provided that access to the patient’s head from above is feasible, the Pencil Insertion Technique provides better
positioning than other insertion techniques. The airway tube is held like a fl ute, with three fi ngers placed above the
junction of the cuff and the tube (Figure 4) and the thumb on the vertical line on the airway tube, which is oriented
anteriorly toward the patient’s nose. Your other hand should be placed under the patient’s head.
See fi gure
f
. Positioning the Ambu AuraOnce using the Pencil Insertion Technique
Insert the tip of the cuff pressing upwards against the hard palate and fl atten the cuff against it. Look carefully into the
mouth to verify that the tip of the cuff is correctly fl attened against the palate before proceeding – push the jaw gently
downwards with your middle fi nger to open the mouth further.
See fi gure
g
. Positioning the Ambu AuraOnce using the Pencil Insertion Technique
As the tip of the cuff is placed correctly in the mouth opening, continue the movement by swinging the mask
inward with a circular motion, pressing the contours of the hard and soft palate. Then advance the Ambu AuraOnce
into the hypopharynx until a defi nite resistance is felt (Figure 5). The motion of the placement should be smooth.
Do not use force. The Ambu AuraOnce should now be correctly located with its tip resting against the upper
esophageal sphincter.
7.4. Insertion Problems
Coughing and breathholding during Ambu AuraOnce insertion indicates inadequate depth of anaesthesia –
immediately deepen anaesthesia with inhalational or intravenous agents, and initiate manual ventilation.
If you cannot open the patient’s mouth suffi ciently to insert the mask, check that the patient is adequately
anesthetized. Ask an assistant to pull the jaw downwards thus making it easier to see into the mouth and verify
the position of the mask.
Diffi culty in manoeuvring the angle at the back of the tongue is one of the most common problems encountered
when inserting the Ambu AuraOnce. The tip must be pressed against the palate throughout or else the tip may fold
on itself or meet an irregularity in the posterior pharynx, e.g. hypertrophied tonsils. Should the cuff fail to fl atten
or begin to curl over as it is inserted, withdraw the mask and reinsert it. In case of tonsillar obstruction, a diagonal
movement of the mask is recommended.
WARNING
Force should never be used during insertion.
7.5. Infl ation
After insertion, the vertical line on the airway tube should be oriented anteriorly towards the patient’s nose. The
typical range of intended depth insertion is marked by the two horizontal lines on the airway tube (see fi gure
d
,
item 5). The Ambu AuraOnce is inserted correctly when the patient’s incisors are between these markings.
Reposition the mask if the patient’s incisors are outside this range. Without holding the tube, infl ate the cuff with
just enough air to obtain a seal, equivalent to intracuff pressures of approximately 60 cm H
2
O. In many cases, only
half of the maximum volume is suffi cient to achieve a seal – please refer to Table 3 for maximum volumes. Check
the cuff pressure continuously during the surgical procedure, either with a cuff pressure gauge or by feeling the
tension in the pilot balloon. This is especially important when N
2
O gases are used.
See fi gure
h
. Infl ation of Ambu AuraOnce.