Page 1091 - The Veterinary Care of the Horse

Maintenance of anaesthesia. Once the horse is lying down an endotracheal tube – a long

hollow tube – is passed through the mouth, via the larynx (i.e. throat) and down into the
VetBooks.ir windpipe. A cuff is blown up around the tube so that the horse only breathes the gases
supplied via the anaesthetic machine. This is a mixture of oxygen and the anaesthetic gas that

keeps the horse ‘asleep’. Sometimes cocktails of intravenous anaesthetic drips are used
instead of the horse breathing in anaesthetic gases.

An overhead hoist may be used to move the horse from the padded box into the theatre –
some patients weigh up to 1,000kg (Figure 24.19). The horse is then carefully positioned on

the operating table, either on its side or back depending on the surgery to be performed.
Positioning is very important, especially for operations lasting several hours. Every attempt is

made to avoid a complication known as post-anaesthetic myopathy, where horse’s muscles
become swollen and painful as a result of poor blood supply caused by them being

compressed by the horse’s weight during the operation. For some horses, this can be a serious
and distressing problem.

Figure 24.19 An overhead hoist is used to carefully manoeuvre the horse into position

During any operation the horse is constantly monitored so that the depth of the