Extradural anaesthesia using lidocaine, ropivacaine, hyperbaric lidocaine and a combination of lidocaine and ropivacaine in mares

Gynaecological surgery and obstetric manipulations in horses are usually performed under extradural anaesthesia. Lidocaine provides effective short duration anaesthesia, but may produce ataxia or recumbency. Ropivacaine has a longer duration of action and produces less motor block, in humans and dogs, when compared to lidocaine. This study investigated the speed of onset and duration of anaesthesia, and the degree of muscle relaxation, produced by various local anaesthetics used for extradural anaesthesia in mares.