What are the three different ways of administering anesthesia?
1) General anesthesia, Regional anesthesia, Local anesthesia
2) Intravenous anesthesia, Inhalation anesthesia, Topical anesthesia
3) Spinal anesthesia, Epidural anesthesia, Nerve block anesthesia
4) Sedation anesthesia, Dissociative anesthesia, Neuroleptic anesthesia