Tracheal-innominate artery fistula may have increased with the use of mechanical ventilation. Four cases were seen in 3½ years in a 400-bed hospital. Low tracheostomy seemed to be a cause, and one occurred after cervical resection of tracheal stenosis. Operation for this complication failed in two cases. In the third case, axilloaxillary bypass was done first and the innominate artery ligated intrapericardially and in the supraclavicular fossa. The patient died of his primary disease six weeks later, but the tracheostomy had healed and the graft functioned until his death. Bypass is believed safe if dissection in the contaminated area is avoided and remote ligation of the artery carried out. The nature of the hemorrhage was not realized in the fourth case and the patient died. A plan for diagnosis and treatment is necessary.