Plus-Hex CLINICAL of GOR during anaesthesia in kittens [ 8 ] . This increase in the risk of GOR has also been documented in human anaesthesia when using LMAs [ 8 ] . There is a 12 Fr gastric channel in the dog v-gel , which allows decompression and the removal of gastric fluid . An oesophageal temperature probe or a stethoscope can also be passed down this channel . endobronchial intubation ( where the tip of the ETT moves past the carina and into one bronchus ). It is easiest if this is done before intubation , by measuring the length of the ETT from the patient ' s thoracic inlet to the incisors , as shown in Figure 9 .
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Intubation aids
Intubation aids are used at the time of intubation and include laryngoscopes , bougies and stylets , which are explained in Table 2 ( previous page ). If you are anticipating a difficult airway in a patient , it is worthwhile having these ready alongside the intubation equipment .
Transcutaneous placement of a catheter or large-bore needle directly into the trachea to deliver oxygen can also be performed in some cases of airway obstruction , if a urinary catheter cannot be passed when a bougie is not available . A urinary catheter with a 3 ml syringe and a 7 mm ETT connector attached can be passed through the larynx to provide oxygen . The catheter can be cut at the connector and used as a stylet ( Figure 8 ).
Figure 9 . Measuring an ETT against a brachycephalic patient .
Before insertion , visually inspect the ETT for any cracks or splits in the tube and ensure there are no dried airway secretions present within the lumen .
The cuff should be inflated and left to sit for 10 minutes to identify any slow leaks . If there is a leak in the ETT cuff , it needs to be repaired or replaced . The cuff should also inflate uniformly ; if it does not , as shown in Figure 10 , it should be disposed of .
Figure 8 . A urinary catheter can be cut at the connector and used as a stylet .
Preparing airway equipment
It is common practice to prepare three different ETT sizes for intubation . Until the larynx is seen at the time of intubation , the required ETT size will not be known , but it can often be estimated by experienced users . The width of the nasal septum can be used to estimate ETT size with 21 % accuracy , while tracheal palpation has 46 % accuracy [ 2 ] . Pre-anaesthesia ultrasonography of the trachea to determine its size has also been reported [ 9 ] .
Additional ETT sizes may be required for breeds in which patients ' airways may vary in size and conformation ( e . g . French bulldogs ). In patients with brachycephalic conformation , the ETT should be cut shorter to reduce the amount of dead space and prevent accidental
Figure 10 . A red rubber ETT that does not inflate uniformly could cause damage to the trachea .
A water-soluble lubricant can be applied evenly around an inflated cuff before placement , but ensure the bevel or Murphy eye is not occluded . Lubrication helps to create a better airway seal by filling in the wrinkles of a cuff that may not be fully inflated [ 10 ] .
When preparing the laryngoscope , ensure the blades sit correctly and the bulb is working . The selected breathing system should be tested before use to ensure it is functioning correctly , without any cracks or leaks .
Volume 38 ( 3 ) • June 2023
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