Anesthesia is an anesthetic used to induce unconsciousness during surgery. The medicine is either inhaled through a breathing mask or tube, or given through an intravenous (IV) line. A breathing tube may be inserted into the windpipe to maintain proper breathing during surgery. This type of anesthesia is most often used in orthopedic procedures epidural anesthetic. The epidural anesthetic is similar to a spinal anesthetic and is commonly used for surgery.