How Can We Prevent Postoperative Pneumonia

Caparelli et al.1 drew attention to postoperative pneumonia in their article titled “Prevention of postoperative pneumonia in noncardiac surgical patients: Prospective study using the NSQIP.” We congratulate the authors for this very illuminating article. However, it will provide a better understanding of the study if the authors clarify some points in the article. First of all, although it is written as a prospective study in the title, it is stated in the Material Methods section that the study is a retrospective study. So, we are confused about the method used in the study. Postoperative pneumonia increases morbidity and mortality, especially after major surgery.2 There are several causes of postoperative pneumonia. Therefore, prevention of postoperative pneumonia requires a special effort. In this article, as stated by the authors, oral hygiene of the patients to prevent pneumonia is very important, but is not enough. Long-term intubation and mechanical ventilation, use of a nasogastric catheter, pre-existing infection, COPD, diabetes mellitus, immune-suppressive conditions, oncological surgery, inadequate postoperative pain treatment, inability to perform intraoperative pulmonary protective mechanical ventilation, and malnutrition in the early postoperative period may enhance the development of postoperative pneumonia due to atelectasis.3 The authors reported that the incidence of pneumonia decreased by using chlorhexidine gluconate for preoperative and postoperative oral hygiene in 1610 patients. Authors do not give information about the extubation process, where extubation took place (operating room or ICU), Acute Physiology and Chronic Health Evaluation II, sequential organ failure assessment scores (SOFA scores) of patients, microbiological examination results, and the day on which postoperative pneumonia developed. In addition, although the study patients were reported to have respiratory physiotherapy; there are no data about the patients who have developed atelectasis and pleural effusion. Another important issue is that the primary aim of the study is not clear. Is the primary aim of determining the effect of preand postoperative use of chlorhexidine on postoperative pneumonia prevention or the success of “quality improved program database” to demonstrate the incidence of pneumonia? The readers are confused about this subject. Another issue is that there are studies showing the effect of mechanical oral cleaning is sufficient to prevent postoperative pneumonia just like brushing teeth.47 Because there is no control group in this study, we cannot make any comparison on this issue. As a result, we are confused about the primary purpose of the study. We cannot understand what are the primary and secondary objectives. No matter how good the data loading and analysis programs are, the results will always be controversial if there is no standardization of the data loaded.