A new classification of descending necrotizing mediastinitis and surgical strategies

BACKGROUND: Descending necrotizing mediastinitis (DNM) is an inflammation occurring in the oropharynx and descending to the deep cervical space and mediastinum, which is a serious infectious disease. The investigation of a new classification system and treatment methods for DNM is still necessary. METHODS: A total of 139 patients with DNM caused by odontogenic or pharyngeal infection were retrospectively analyzed in last 20 years in the Ninth People’s Hospital Affiliated to Shanghai Jiao Tong University School of Medicine. The patients were divided into the traditional treatment Group T (Group T: 43 patients) and the new classification Group N (Group N: 96 patients). A new DNM classification was developed based on the progression of mediastinal infection as follows: type Ia: infection in the anterosuperior mediastinum; type I: infection in the anterior mediastinum; type II: infection in the posterior mediastinum; and type III: infection of the whole mediastinum. RESULTS: There were 49, 8, 10, and 29 patients classified as type Ia, I, II, and III, respectively in the Group N. The type Ia DNM patients were managed with transcervical mediastinal drainage, and the patients with types I and II DNM underwent open (thoracoscopic) surgery, 1 patient within types I died. The 29 patients with type III were managed with unilateral or bilateral open (thoracoscopic) surgery, among them, 8 patients died. The mortality rate for patients with type III DNM was 27.6%. The overall mortality rate in Group N was 9.4%. The mortality rate for patients in the Group T was 25.6%. The mortality rate of Group N was significantly lower than that of Group T (P<0.05). CONCLUSIONS: We have carried out a new clinical classification of DNM, and selected the appropriate treatment method according to the classification, and achieved a better effect than the traditional treatment method.