If these occur while you are waking up, they may be related to the length of your operation, the different drugs used for your anaesthetic and/or how sensitive you are to the drugs used. Your anaesthetist uses their training and experience to 'tailor' the drugs and doses for your operation to minimize these effects. Sometimes, however, e.g. after major operations, the anaesthetist will make you a bit drowsy on purpose by using strong pain-killers to make you more comfortable.
For more information please refer to www.allaboutanaesthesia.com.au
