or radiography ) the volatile anaesthetic gas should be turned off and the breathing system disconnected and reconnected , to prevent tracheal rupture by the tube twisting within the trachea ; this is especially important in cats ( Hughes , 2016 ).
Extubation is usually performed with the cuff deflated and when the patient ’ s gag / cough / swallow reflex has returned . In cats , it is ideal to remove the tube just prior to this , to prevent laryngeal over-stimulation . The animal must be able to swallow any potential vomit or regurgitation , should it occur , to minimise the risk of aspiration pneumonia , and it is essential to be confident that it is able to manage with an unprotected airway . If there is particular concern that there is fluid , blood or other debris close to the larynx , for example , in cases of brachycephalic obstructive airway syndrome ( BOAS ), then the ETT may be removed with a partially inflated cuff or , in rare cases , with a fully inflated cuff . This is done to bring any debris sitting proximal to the cuff up along the trachea and to stimulate the cough reflex , thus protecting the airway . Animals should also be positioned in sternal recumbency with their head raised . Careful monitoring during the recovery period is essential ( Dugdale et al ., 2020 ).
Figure 7 . Using a brush to clean the inside of an ETT
Figure 7 demonstrates the removal of the mucus from inside the ETT .
Figure 8 shows a narrow ETT with dried and hardened mucus causing an almost complete blockage . This tube was found with the ready-to-use ETTs . If used , this could have caused potentially serious complications .
Once the tube is removed , it is common for it to be left on the floor , in a sink or on the side . It is vital that the veterinary nurse takes responsibility for the aftercare of the tube and understands the procedure for cleaning .
Figures 6 to 9b demonstrate prior improper cleaning of a number of ETTs . They were found when the pre-use checks were being made during preparation for anaesthesia .
Figure 6 shows some mucus inside an ETT . The tube had not been properly cleaned and an ETT brush was not used to remove the big bits of debris inside .
Figure 8 . ETT blocked by dried mucus .
Figure 9a depicts an ETT with an uninflated cuff selected for use . Figure 9b ( overleaf ) shows the dry debris found on inflating the cuff to perform a leak check . This is most likely due to the cuff not being inflated during the cleaning process , allowing debris to remain in the folds of the uninflated cuff .
Figure 6 . Mucus left in an ETT following improper cleaning .
Figure 9a . Uninflated cuff of a cleaned ETT .
Volume 37 ( 5 ) • November 2022
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