Preventive Effect on Post-Operative Pneumonia of Oral Health Care among Patients Who Undergo Esophageal Resection: A Multi-Center Retrospective Study

Background: Post-operative pneumonia is a frequent and possibly fatal complication of esophagectomy and is likely caused by aspiration of oropharyngeal fluid that contains pathogenic micro-organisms. We conducted a multi-center retrospective study to investigate the preventive effect of oral health care on post-operative pneumonia among patients with esophageal cancer who underwent esophagectomy. Methods: A total of 280 patients underwent esophagectomy at three university hospitals. These patients were divided retrospectively into those who received pre-operative oral care from dentists and dental hygienists (oral care group; n = 173) and those who did not receive such care (control group; n = 107). We evaluated the correlations between the occurrence of post-operative pneumonia and 18 predictive variables (patient factors, tumor factors, treatment factors, and pre-operative oral care) using the χ2 test and logistic regression analysis. The differences of mean hospital days and mortality rate in both groups were analyzed by the Student t-test. Results: Age, post-operative dysphagia, and absence of pre-operative oral care were correlated significantly with post-operative pneumonia in the univariable analysis. Multivariable analysis revealed that diabetes mellitus, post-operative dysphagia, and the absence of pre-operative oral care were independent risk factors for post-operative pneumonia. The mean hospital stay and mortality rate did not differ between the oral care and control groups. Conclusion: Pre-operative oral care may be an effective and easy method to prevent post-operative pneumonia in patients who are undergoing esophagectomy.