Abstract & Commentary

To Brush 'Em or Not: Does Tooth Brushing Prevent Ventilator-Associated Pneumonia?

By Linda L. Chlan, RN, PhD, School of Nursing, University of Minnesota, is Associate Editor for Critical Care Alert.

Dr. Chlan reports that she receives grant/research support from the National Institutes of Health.

Synopsis: The evidence to date reviewed in this paper does not strongly support tooth brushing in all critically ill patients to prevent ventilator-associated pneumonia and further high-quality research is needed to address the weaknesses in this body of literature.

Source: Ames NJ. Evidence to support tooth brushing in critically ill patients. Am J Crit Care 2011;20:242-250.

The purpose of this review paper was to summarize the evidence on the effect of tooth brushing to prevent ventilator-associated pneumonia (VAP) in critically ill adults and children receiving mechanical ventilatory support. The basic premise is that oral-cavity bacteria can cause VAP and that regular tooth brushing removes bacteria from the mouth that cause VAP. The author notes that the main issue with regular oral care, including tooth brushing in mechanically ventilated patients, is the potential for oral-cavity bacteria to enter the bloodstream from the breakdown of mucosal and gingival tissue in those patients with poor dental health. If this occurs, the patient is at risk for bacteremia and hypotension, particularly in those patients who are immunologically compromised. The question remains as to whether regular tooth brushing consistently prevents VAP such that the intervention outweighs the risk for bacteremia.

A total of eight published articles investigating tooth brushing on VAP prevention were reviewed. Of these papers, three were randomized controlled trials (RCTs), one was case-control, and four had observational designs. Only one paper enrolled critically ill children, including nine who were intubated for less than 24 hours. It was noted that this study was the first-ever publication to describe the oral microbiome in children. Five studies measured VAP rates retrospectively and not all designs used a control or usual-care group for comparison. A variety of methods were used to confirm VAP, including the clinical pulmonary infection score (CPIS), cultures, or bacterial composition of the oral microbiome. In addition to VAP rates, other outcomes included length of time mechanically ventilated, length of ICU stay, mortality, and antibiotic-free days. Five of the eight studies had positive findings for the prevention of VAP with regular tooth brushing. The remaining three studies had non-significant findings for VAP reduction or prevention. There were, however, inconsistent diagnoses of VAP reported across studies using either the CPIS or cultures; not all VAP rates were documented microbiologically or prior to intervention. Further, there was inconsistent adherence to the oral care protocols in some studies. Lastly, there was inconsistency among studies in the reporting and implementation of the oral care regimens, the agent(s) used, and the frequency at which oral care was performed.

The author suggested several areas for improving the rigor and science related to this topic, including the microbiological definition of VAP; determination of the baseline VAP rates prior to the intervention; methods to ensure adherence and integrity of the intervention protocol; and the need for prospective studies including an emphasis on patient safety to include hypotension and bacteremia rates. The author concluded that while tooth brushing may be an important intervention, the importance of tooth brushing in the prevention of VAP cannot be determined from the current evidence. Regardless, it was recommended that every ICU have an oral care procedure that includes oral assessments, suctioning, providing lip and oral mucosa moisture, and taking an oral health history.

COMMENTARY

While not an exhaustive systematic review, this article provides the critical care clinician an overview of the currently available evidence on the effectiveness of tooth brushing for the prevention of VAP in mechanically ventilated patients. This paper did not review VAP prevention care bundles. Based on the evidence, regular tooth brushing requires further scrutiny, particularly for those patients with poor dental health. While twice daily tooth brushing in healthy individuals is a "best practice," critical care clinicians are wise to evaluate the evidence given the limitations and inconsistencies in the literature and the potential for increased patient risk.

As with many literature reviews, individual studies describe varying protocols, definitions, and use different outcome measurements. This makes it difficult to pool results for a meta-analysis. There is a clear need for prospective studies that are adequately powered to detect significant findings. Careful assessment and monitoring of the ICU environment during the conduct of VAP prevention studies should be included in order to determine the impact of any practice changes on the variables of interest. Toward this end, the author provides many excellent areas in which the science can be improved. The suggestions for future research could easily be used as the basis for a research agenda to determine best practices for oral care, which should include the input of dentists. While oral assessment and oral care continue to be important practices in the care of mechanically ventilated patients, the evidence to support wide-spread tooth brushing is not apparent at this time given the inconsistent findings.