Pre-anaesthetic medication

An overview

Pre-anaesthetic medication is often included in anaesthetic protocols for larger species. The advantages of this are:

• Administering sedatives or tranquillisers can reduce aggression and fear or apprehension and aid stress-free induction of anaesthesia.
• Use of analgesics can reduce pain, especially in the immediate post-operative period, and may provide more effective pain relief through ‘pre-emptive analgesia’.
• Atropine or glycopyrrolate can be given to reduce bronchial and salivary secretions and to protect the heart from vagal inhibition caused by some procedures (e.g. endotracheal intubation, manipulation of the viscera during surgery). It is advisable to use glycopyrrolate in rabbits, as atropine is often relatively ineffective in this species.
• Use of sedatives, tranquillisers and analgesics can reduce the amount of anaesthetic needed to produce the desired level of anaesthesia. These agents also provide smoother induction of anaesthesia and a smoother recovery.