(54) Air in Maxillofacial Infections Predicts Worse Patient Outcomes

Abstract: When localized odontogenic infections disseminate into the fascial spaces of the head and neck, these infections are categorized as severe odontogenic infections and require incision and drainage in the operating room setting.¹ The presence of air inclusions or gas bubbles within an infection on imaging is often thought to be a strong indicator of a serious infection.² This sign is also known as infection-related subcutaneous emphysema and is caused by bacteria that produce gas as a byproduct. Currently, no studies investigate the meaning and implications of this phenomenon for odontogenic infections. The purpose of this study was to correlate the presence of air within an odontogenic infection on computed tomography (CT) with patient outcomes.

A retrospective study was designed to compare patients admitted with odontogenic abscesses with and without air present within their infection on their CT scan at initial presentation to the emergency department. Subjects included in the dataset had presented to the University of Illinois Hospital between the years 2005 and 2024 with a confirmed odontogenic infection that required incision and drainage in the operating room. The primary objective was to determine if the presence of air on CT was correlated with higher severity of head and neck infections, measured as total length of stay. Secondary outcomes evaluated were intensive care unit admission, need for secondary incision and drainage procedures, need for intubation, and intubation duration. The data were analyzed using the χ2 and t test, with statistical significance set at P < .05.

After application of inclusion and exclusion criteria, 321 subjects were included in this study. The final dataset included 176 (55%) males and 145 (45%) females, with mean age of 41.1 ± 18.6 (range 6-89). Of the 321 subjects, 86 (26.8%) had air present within the infection on imaging. The mean length of stay for subjects with air was 5.9 ± 7.8 days compared to 3.3 ± 3.1 days for those without air (P < .0001). There was a higher rate of ICU admission among subjects with air, 16.3%, compared to 10.6% of the cohort without air (P = 0.167). The need for multiple incision and drainage procedures was also higher in the air cohort, 16.3% needing re-drainage, compared to only 8.1% (P = .033). The need for perioperative intubation was equivalent in the two groups, 9.3% of patients with air, with mean days of intubation of 2.6 ± 2.4 days, compared to 8.1% in the no air group, with 2.3 ± 1.7 mean days of intubation (P = 0.214).

In conclusion, infections with air present on CT were more severe in regards to length of hospital stay and need for additional incision and drainage procedures.


References:
[1] Neal, T. W., & Schlieve, T. (2022). Complications of Severe Odontogenic Infections: A Review. Biology, 11(12), 1784. https://doi.org/10.3390/biology11121784
[2] Richards C, Walker TW, Girgis S, et al ‘Bubble sign’: gas-forming bacteria from an odontogenic infectionBMJ Case Reports CP 2020;13:e233946. https://casereports.bmj.com/content/13/6/e233946.long