P-239DISSEMINATION PATHWAY OF ODONTOGENIC DESCENDING NECROTIC MEDIASTINITIS INFLUENCES SURVIVAL AND AGGRESSIVENESS OF SURGICAL APPROACH

Abstract

Objectives: Descending necrotic mediastinitis (DNM) is the most dangerous and difficult to treat complication of neck and odontogenic infections and has a high mortality rate, mainly due to bacterial polymorphism and delayed diagnosis. Our objective was to evaluate the efficiency of surgical treatment related to the dissemination path. Methods: Twenty-six cases with odontogenic DNM treated between 2000 and 2016 were studied retrospectively. In all cases the diagnosis was established clinically and by CT scan. Other causes for mediastinitis were excluded from the study. We analysed outcome and complications by neck dissemination path, as shown on CT: group A (14 cases) posterior plane dissemination and group B (12 cases) anterior disseminations. All patients underwent urgent cervicotomy and mediastinal drainage and repeated debridement and daily lavage. Eight patients in group A benefited from immediate thoracotomy and mediastinotomy, 2 had delayed thoracotomy after 2 days. No thoracotomy was performed in group B. Pleural drainage was performed in all cases in group A, and in 7 cases in group B. Results: For group A we recorded complications in 86% cases (ARDS, MSOF, haemorhage, empyema, purulent pericarditis, extended chest wall cellulitis, tracheal fistulas, cutaneous defects, vasculitis). Recorded mortality was 7 cases. Hospital stay was 4.7 weeks. For group B complication rate was 62%, 1 death by aspiration was recorded, thus unrelated to mediastinal infection. Hospital stay was similar. In group A mortality was higher in patients with late or no thoracotomy, even for cases with less apparent dissemination and aggressive antibiotherapy. Conclusions: Acute DNM with posterior dissemination is more aggressive and complications occur faster. Emergent thoracotomy and extended mediastinal drainage +/-pericardotomy associated with cervicotomy is mandatory to improve survival. Antibiotic therapy and cervicotomy alone are not sufficient.