Relationship between the pathogens of postoperative pneumonia after an esophagectomy for thoracic esophageal cancer and the aggregate length of preoperative hospital stay

Background. Oral care, respiratory physiotherapy, and rehabilitation for swallowing disorders are thought to be useful preventative measures for postoperative pneumonia in major surgeries. Despite these measures, postoperative pneumonia after an esophagectomy remains frequent and severe. However, few reports have documented the pathogens associated with postoperative pneumonia following surgery for esophageal cancer. Methods. Oral care, respiratory physiotherapy, and rehabilitation for swallowing disorders were introduced into the clinical path for transthoracic esophagectomies for esophageal cancer, and we retrospectively analyzed 191 patients who underwent an esophagectomy between September 2002 and December 2008. In 80 of 191 patients, sputum was harvested using routine bronchoscopy on the first or second postoperative day, and the pathogens were evaluated. The data were analyzed retrospectively. By reviewing the hospital records of all patients involved, information was obtained on demographic characteristics, preoperative pulmonary status, postoperative course, and aggregate length of preoperative hospital stay. The incidence of postoperative pneumonia was investigated, and the correlation between the aggregate length of preoperative hospital stay and infection by pathogens was analyzed. Results. Postoperative pneumonia was diagnosed in 21 of 191 patients (11.0%). Univariate analyses of the relationships between postoperative pneumonia and all potential risk factors, including the length of preoperative hospital stay, showed no significant difference. Thirteen of 80 cases who underwent routine bronchoscopy contracted postoperative pneumonia. In 7 of 80 cases in which sputum was harvested by bronchoscopy, Pseudomonas aeruginosa was detected. The aggregate length of preoperative hospital stay was 5 days or more in all 7 cases. The positive rate for Pseudomonas aeruginosa in the postoperative pneumonia cases was 23.1% (3 of 13). Conclusions. The rate of postoperative pneumonia was about 10% despite preventative efforts including oral care, respiratory rehabilitation, and rehabilitation for swallowing disorders. In cases of postoperative pneumonia after a thoracic esophagectomy for esophageal cancer among patients with preoperative hospital stays of 5 days or more, it may be advisable to select empiric therapy covering multidrug-resistant gram-negative pathogens, especially Pseudomonas aeruginosa.