Do not tell the children: toothbrushing does not make a difference (in your ventilator-associated pneumonia rates).

www.ccmjournal. org 691 Ventilator-associated pneumonia (VAP) is an important cause of morbidity and mortality in ventilated critically ill patients (1), and its control is pivotal in ICUs worldwide. “Aspiration of oropharyngeal pathogens, or leakage of secretions containing bacteria around the endotracheal tube cuff” are cited as the primary routes of bacterial entry into the lower respiratory tract (2). Indeed, several measures have been developed to prevent VAP by reducing the risk of aspiration, such as suction of subglottic secretions, semirecumbent position and enteral feeding, and by modulating oral colonization using oral antiseptic or selective digestive decontamination protocols (2). The development and implementation of a comprehensive oral hygiene program was early proposed by guidelines from the American Thoracic Society and the Infectious Diseases Society of America (2), despite this recommendation was based on the results of a single randomized controlled trial performed in patients undergoing coronary artery bypass surgery (3). After this study, a number of trials advocated oral hygiene to reduce the colonization of dental plaque as a strategy critical in the prevention of VAP, and a recent meta-analysis summarized this evidence demonstrating a beneficial effect of oropharyngeal care using chlorhexidine compared to standard hygiene. Povidoneiodine was evaluated only in two studies, and the efficacy remained unclear (4). Currently, guidelines recommend oral care as a first line strategy to reduce VAP rates (5, 6). Recently, there has also been a dramatic success in improving the quality of patient care by focusing on the implementation of a group or “bundle” of evidence-based preventive practices to achieve a better outcome than when implemented individually. This approach has been already successfully applied to the management of VAP in the critical care setting (7, 8), and most of bundles include oral care with chlorhexidine among other measures. Whereas oral hygiene is recognized of primary importance in VAP prevention, the best strategy to achieve it is still an open question. The evidence is limited by the small number of randomized controlled studies and the heterogeneity of oral hygiene solutions, tools, and techniques (9). Recently, a consensus based clinical guideline for oral hygiene in critically ill patients from the Australian NSW Health Intensive Care Coordination and Monitoring Unit concluded that there is no evidence, at the moment, to support the use of one oral rinse over another in mouth care with the exception of the use of chlorhexidine gluconate 0.12% in the cardiac surgical patient population (10). The same guidelines extensively evaluated the role of toothbrushing, assessing that if brushing is the best method for plaque removal from the tooth surfaces and can assist in reducing microbial colonization, large and high-quality studies are advocated to verify the impact of such method on VAP (10). In this issue of Critical Care Medicine, Alhazzani et al (11) present the results of a systematic review and meta-analysis investigating the effect of oral care with toothbrushing on the prevention of VAP in adult critically ill patients receiving mechanical ventilation. The study does not reveal any significant positive effect of toothbrushing on VAP rates, mortality, and length of hospital stay. The study has several strength aspects including an extensive search strategy, inclusion of randomized controlled trials only, and quality appraisal based on Cochrane Collaboration tools. However, only one study was judged to be at low risk of bias (12), and it is the unique where chlorexidine is not included among baseline strategy of both arms. Subgroup analysis by exclusion of this single trial showed two major results. First, the high statistical heterogeneity early obtained combining all studies dropped from 62% (I value) to 0%, which means that combining studies including and not including chlorexidine as part of the oral care strategy partly explained the source of heterogeneity between studies. Second, the subgroup analyses showed no effect of toothbrushing in VAP rates, whereas the excluded study (12) is the single trial that showed a significant impact of toothbrushing on VAP. We can therefore conclude that, as soon as oral care with chlorexidine is used, the best strategy has likely been applied already, irrespectively of the use of toothbrushes or toothettes. To conclude, in the current perspective of difficult financing for a number of hospital worldwide which implies scarce human and material resources, we feel the need to focus on Do Not Tell the Children: Toothbrushing Does Not Make a Difference (in Your Ventilator-Associated Pneumonia Rates)*