How could anesthesia come up as cocaine in a drug test and what types of anesthesia?

Cocaine is used: as a topical anesthetic in anesthesia for example in an awake nasal intubation because it provides both analgesia and vasoconstriction and decreased bleeding in a very vascular area

Nasal surgery: Ear, nose & throat surgeons (otolaryngologists) often use Cocaine to numb the nose before surgery. Examples: surgery for deviated septum or turbinate resection. Cocaine is used as a local anesthetic to numb the area and to constrict blood vessels in order to reduce bleeding.