title: Identification of the epidural space: is loss to air a safe technique?
authors.forename: J A
authors.initials: JA
authors.lastname: Aldrete
mesh_terms: D000767:Anesthesia, Epidural / Q000009:adverse effects / Q000379:methods; D002404:Catheterization; D006261:Headache / Q000209:etiology; D006801:Humans