Background Ventilator-associated pneumonia (VAP) is defined as pneumonia developing in persons who have received mechanical ventilation for at least 48 hours. VAP is a potentially serious complication in these patients who are already critically ill. Oral hygiene care (OHC), using either a mouthrinse, gel, toothbrush, or combination, together with aspiration of secretions may reduce the risk of VAP in these patients. Objectives To assess the effects of OHC on the incidence of VAP in critically ill patients receiving mechanical ventilation in intensive care units (ICUs) in hospitals. Search methods We searched the Cochrane Oral Health Group's Trials Register (to 14 January 2013), CENTRAL (The Cochrane Library 2012, Issue 12), MEDLINE (OVID) (1946 to 14 January 2013), EMBASE (OVID) (1980 to 14 January 2013), LILACS (BIREME) (1982 to 14 January 2013), CINAHL (EBSCO) (1980 to 14 January 2013), Chinese Biomedical Literature Database (1978 to 14 January 2013), China National Knowledge Infrastructure (1994 to 14 January 2013), Wan Fang Database (January 1984 to 14 January 2013), OpenGrey and ClinicalTrials.gov (to 14 January 2013). There were no restrictions regarding language or date of publication. Selection criteria We included randomised controlled trials (RCTs) evaluating the effects of OHC (mouthrinse, swab, toothbrush or combination) in critically ill patients receiving mechanical ventilation. Data collection and analysis Two review authors independently assessed all search results, extracted data and undertook risk of bias. We contacted study authors for additional information. Trials with similar interventions and outcomes were pooled reporting odds ratios (OR) for dichotomous outcomes and mean differences (MD) for continuous outcomes using random-effects models unless there were fewer than four studies. Main results Thirty-five RCTs (5374 participants) were included. Five trials (14%) were assessed at low risk of bias, 17 studies (49%) were at high risk of bias, and 13 studies (37%) were assessed at unclear risk of bias in at least one domain. There were four main comparisons: chlorhexidine (CHX mouthrinse or gel) versus placebo/usual care, toothbrushing versus no toothbrushing, powered versus manual toothbrushing and comparisons of oral care solutions. There is moderate quality evidence from 17 RCTs (2402 participants, two at high, 11 at unclear and four at low risk of bias) that CHX mouthrinse or gel, as part of OHC, compared to placebo or usual care is associated with a reduction in VAP (OR 0.60, 95% confidence intervals (CI) 0.47 to 0.77, P < 0.001, I-2 = 21%). This is equivalent to a number needed to treat (NNT) of 15 (95% CI 10 to 34) indicating that for every 15 ventilated patients in intensive care receiving OHC including chlorhexidine, one outcome of VAP will be prevented. There is no evidence of a difference between CHX and placebo/usual care in the outcomes of mortality (OR 1.10, 95% CI 0.87 to 1.38, P = 0.44, I-2 = 2%, 15 RCTs, moderate quality evidence), duration of mechanical ventilation (MD 0.09, 95% CI -0.84 to 1.01 days, P = 0.85, I-2 = 24%, six RCTs, moderate quality evidence), or duration of ICU stay (MD -0.21, 95% CI -1.48 to 1.89 days, P = 0.81, I-2 = 9%, six RCTs, moderate quality evidence). There was insufficient evidence to determine whether there is a difference between CHX and placebo/usual care in the outcomes of duration of use of systemic antibiotics, oral health indices, microbiological cultures, caregivers preferences or cost. Only three studies reported any adverse effects, and these were mild with similar frequency in CHX and control groups. From three trials of children aged from 0 to 15 years (342 participants, moderate quality evidence) there is no evidence of a difference between OHC with CHX and placebo for the outcomes of VAP (OR 1.07, 95% CI 0.65 to 1.77, P = 0.79, I-2 = 0%), or mortality (OR 0.73, 95% CI 0.41 to 1.30, P = 0.28, I-2 = 0%), and insufficient evidence to determine the effect on the outcomes of duration of ventilation, duration of ICU stay, use of systemic antibiotics, plaque index, microbiological cultures or adverse effects, in children. Based on four RCTs (828 participants, low quality evidence) there is no evidence of a difference betweenOHC including toothbrushing (+/- CHX) compared to OHC without toothbrushing (+/- CHX) for the outcome of VAP (OR 0.69, 95% CI 0.36 to 1.29, P = 0.24, I-2 = 64%) and no evidence of a difference for mortality (OR 0.85, 95% CI 0.62 to 1.16, P = 0.31, I-2 = 0%, four RCTs, moderate quality evidence). There is insufficient evidence to determine whether there is a difference due to toothbrushing for the outcomes of duration of mechanical ventilation, duration of ICU stay, use of systemic antibiotics, oral health indices, microbiological cultures, adverse effects, caregivers preferences or cost. Only one trial compared use of a powered toothbrush with amanual toothbrush providing insufficient evidence to determine the effect on any of the outcomes of this review. A range of other oral care solutions were compared. There is some weak evidence that povidone iodine mouthrinse is more effective than saline in reducing VAP (OR 0.35, 95% CI 0.19 to 0.65, P = 0.0009, I-2 = 53%) (two studies, 206 participants, high risk of bias). Due to the variation in comparisons and outcomes among the trials in this group there is insufficient evidence concerning the effects of other oral care solutions on the outcomes of this review. Authors' conclusions Effective OHC is important for ventilated patients in intensive care. OHC that includes either chlorhexidine mouthwash or gel is associated with a 40% reduction in the odds of developing ventilator-associated pneumonia in critically ill adults. However, there is no evidence of a difference in the outcomes of mortality, duration of mechanical ventilation or duration of ICU stay. There is no evidence that OHC including both CHX and toothbrushing is different from OHC with CHX alone, and some weak evidence to suggest that povidone iodine mouthrinse is more effective than saline in reducing VAP. There is insufficient evidence to determine whether powered toothbrushing or other oral care solutions are effective in reducing VAP.
