What exactly an anaesthetist does depends on what area they specialise. In general, will see and assess pre op patients for suitability for anaesthetics and consider which drugs to use if special considerations need to be made. Administer and monitor patient during op, manitain optimum conditions (fluid balance, BP, temp), keep them paralysed (if required) pain free and unaware. Insert lines for during and post op period, intubate or privide airway. Post op pain relief. Some do chronic pain, some acute management, regional and general anaesthesia. Sub specialty generally ITU/ICU anaesthetics, in which case everything in a critically ill patient, monitoring and treating all physiological systems. Not good for pateint communication as most are sedated/unconscious, but challenging as no patient report of whats going on, and lots of interaction with family.