Factors affecting patients with concurrent deep neck infection and aspiration pneumonia

Background: Deep neck infection (DNI) is a life-threatening condition of the deep neck spaces with potential to obstruct the airway. Aspiration pneumonia (AP), which results from aspiration of colonized oropharyngeal or upper gastrointestinal contents, is a respiratory infection that affects the lungs, wherein the air sacs are filled with purulent fluid. The cooccurrence of these two diseases can cause severe damage to the respiratory system, leading to morbidity and mortality. However, the risk factors for concurrent DNI and AP have not yet been investigated. This study aimed to address this issue. Methods: A total of 561 DNI patients were enrolled in this study between June 2016 and December 2021. Among these patients, 26 had concurrent DNI and AP at the time of diagnosis. Relevant clinical variables were assessed. Results: In the univariate analysis, age > 60 years (OR = 3.593, 95% CI: 1.534-8.414, p = 0.002), C-reactive protein (OR = 1.005, 95% CI: 1.001-1.008, p = 0.003), involvement of >= 3 spaces (OR = 4.969, 95% CI: 2.051-12.03, p < 0.001), and retropharyngeal space involvement (OR = 4.546, 95% CI: 1.878-11.00, p < 0.001) were significant risk factors for concurrent DNI and AP. In the multivariate analysis, age > 60 years (OR = 2.766, 95% CI: 1.142-6.696, p = 0.024) and retropharyngeal space involvement (OR = 3.006, 95% CI: 1.175-7.693, p = 0.021) were independent risk factors for concurrent DNI and AP. The group with concurrent DNI and AP had longer hospital stays (p < 0.001) and lower rates of incision and drainage (I&D) open surgery (p = 0.020) than the group with DNI alone. There were no significant differences in pathogens (p > 0.05) between the groups. Conclusions: Both DNI and AP can independently compromise the airway, and the concurrence of these two conditions makes airway protection more difficult. Age > 60 years and retropharyngeal space involvement were independent risk factors for the concurrence of DNI and AP. The group with concurrent DNI and AP had longer hospital stays and lower rates of I&D open surgery than the group with DNI alone. There were no differences in DNI pathogens according to concurrent AP status.