Aspiration Pneumonia and Perioperative Antibiotic Use in Transoral Robotic and Laser Microsurgery

INTRODUCTION: Aspiration pneumonia can follow transoral surgery for head and neck cancer due to abnormal swallowing function. While prophylactic post-operative antibiotics may decrease the incidence of this complication, excessive use can be costly, and lead to adverse reactions or antibiotic resistance. The objectives of this study are to 1) determine if the use post-op antibiotics prevent aspiration pneumonia. 2) Identify any complications related to the use of antibiotics. METHODS: A retrospective review of 155 patients who underwent transoral surgery for squamous cell carcinoma (SCCA) between May 2008 and June 2014 was conducted and demographic data was collected. The MD Anderson dysphagia inventory (MDADI) was used to assess swallowing function. RESULTS: Sixteen of 122 patients that received postoperative antibiotics (13.1%) developed pneumonia, compared to 4/32(12.5%) patients who did not receive antibiotics (p=0.925). Average antibiotic course was 39.2 days (median=23). Average time to infection was 290 days (median=217, range=11-979). Univariate analysis did not show a correlation between patients that developed pneumonia and antibiotic use (p=1.00), location (p=.1642), overall stage (p=.1599), comorbidity status (p=.5327), tobacco use (p=.6328), alcohol use (p=.351), and gastrostomy tube dependence (p=.254). Univariate analysis did show a correlation between pneumonia and tracheostomy placement (p=.0316), T stage (p=.0357), and days post-op of PEG placement (p=.0297). Multivariate analysis showed correlation with tracheostomy placement (p=.0236). No patients contracted C. difficile infection. No trend was observed in post-operative MDADI score. DISCUSSION: Routine use of post-operative prophylactic antibiotic does not correlate with a decreased rate of pneumonia or improved functional outcomes. Given that tracheostomies are performed mainly for pulmonary toilet, and a larger T stage results in larger resections, the significant correlation was expected. PEG placement in pneumonia patients was significantly later than patients with no pneumonia. This, and the fact that pneumonia generally developed outside of the 30-day perioperative period, supports the idea that aspiration pneumonia development reflects a chronic worsening swallowing dysfunction. Therefore, dysphagia immediately after surgery is probably not a significant risk factor for developing aspiration pneumonia and routine post-operative antibiotic use for pneumonia prevention is not indicated after transoral surgery.