Risk factors for delayed oral dietary intake in patients with deep neck infections including descending necrotizing mediastinitis

Although clinical outcomes of descending necrotizing mediastinitis (DNM) and/or deep neck infection (DNI) have been extensively reported, no study has addressed delay in recovering oral ingestion after surgical interventions other than sporadic case reports. We herein compared clinical features of DNM and DNI cases over the same period, and clarified precipitating factors of delay in recovering oral ingestion by logistic regression analysis. We reviewed records of patients with DNI and DNM at our institution from August 2005 to July 2015. We extracted data on patient age, sex, complication with diabetes mellitus, gas gangrene, extension of infections, operative procedure, tracheotomy, bacterial results, and duration of empirical antibiotic therapy. Patients were categorized into three groups according to vertical spread of infection: 60 DNI patients without extension below the hyoid bone (group-A), 48 DNI patients with extension below the hyoid bone without DNM (group-B), and 10 DNM patients (group-C). Age, diabetes mellitus, and gas gangrene were significantly different among the groups. Concerning surgical intervention, tracheotomy was significantly less frequently performed in group-A (25%) than the other groups (74%) (p < 0.001). Logistic regression analyses revealed that extension of infections below the hyoid bone and tracheotomy were significantly associated with delayed oral dietary intake [odds ratios (95% confidence intervals) 2.96 (1.06-8.28) and 10.69 (3.59-31.88), respectively]. Along with DNM patients, patients who undergo tracheotomy for infections that extend below the hyoid bone should receive postoperative care with careful attention to avoid delay in recovering oral ingestion.