Division of Zoological Medicine, Faculty of Veterinary Medicine, Utrecht University, Utrecht, Netherlands
In rabbits, anesthetic risks are significantly higher than in dogs and cats. During prolonged anesthesia, assuring a patent upper airway is vital to increase the chances of survival. Currently, the most common method to achieve this is endotracheal intubation. This method of intubation is complicated by the rabbit’s oropharyngeal anatomy and tendency to develop laryngospasm during intubation. In addition, post-intubational complications may occur, such as respiratory arrest, laryngeal/tracheal injury or edema, or development of tracheal strictures.
In 2009, the V-gel® supraglottic airway device (SGAD; DocsInnovent, UK) was developed with the use of rabbit cadavers. After refinement of the prototype, which was designed specifically to fit the rabbit’s oropharyngeal anatomy, clinical trials were performed to validate its use in clinical practice. Recent studies have demonstrated that the SGAD can be placed faster compared to an endotracheal tube ETT). The amount of attempts to place an ETT is also much higher compared to the SGAD. In addition, less mucosa trauma is seen when using the SGAD. When using positive pressure ventilation, leakage of anaesthetic pressure was seen 4 out of 9 rabbits at 6 cm H2O, while in the other 5 rabbits this leakage was only seen at pressures higher than 16 cm H2O. In another study, however, isoflurane leakage was comparable between rabbits in which an ETT or a SGAD was used. Other (minor) complications which have been seen include linguocyanosis, gastric inflation, insertion difficulties due to improper anesthetic depth or dental issues. Based on these findings the V-gel SGAD can be considered a safe and suitable alternative to ETT in rabbits.
References
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