INTRODUCTIONMediastinitis is one of the most feared complications for thoracic surgeons, being a significant factor in morbidity and mortality in thoracic surgery.OBJECTIVETo find a new alternative in order to prevent mediastinitis, reducing the morbidity and mortality.METHODSA retrospective study including 1020 patients operated between February 2002 and October 2005. Patients underwent bypass surgery and vancomycin paste was used rather than bone wax in all cases.RESULTSPatients were followed-up for 45 months; there were only five (0.49%) cases of mediastinitis; no deaths were observed.CONCLUSIONThe use of Vancomycin paste to replace bone wax proved to be a great allied to prevent mediastinitis after thoracic surgery.