Oral care for critically ill ventilated patients

Critically ill patients need mechanical ventilation if their ability to breath unassisted is compromised. Ventilator-associated pneumonia (VAP) is defined as pneumonia developing in a patient who has received mechanical ventilation for at least 48 hours and is reported to develop in 6-52% of ventilated patients and be associated with an attributable mortality of 10%.

The aim of this Cochrane review was to assess the effects of oral hygiene care (OHC) on incidence of ventilator-associated pneumonia in critically ill patients receiving mechanical ventilation in hospital intensive care units (ICUs).

Methods

Searches were carried out in the Cochrane Oral Health’s Trials Register (to 17 December 2015), the Cochrane Central Register of Controlled Trials (CENTRAL) Medline, Embase, LILACS, CINHAL,Chinese Biomedical Literature Database,China National Knowledge Infrastructure Wan Fang Database, VIP Database, ClinicalTrials.gov and the World Health Organization International Clinical Trials Registry Platform databases with no restrictions.

Randomised controlled trials (RCTs) evaluating the effects of OHC (mouthrinse, swab, toothbrush or combination) in critically ill patients receiving mechanical ventilation for at least 48 hours were considered. Two reviewers independently selected studies, abstracted data and assessed risk of bias. Standard Cochrane approaches were used for analysis with risk ratios(RR) being used for dichotomous outcomes and mean difference (MD) for continuous outcomes

Results

38 RCTs involving a total of 6016 patients were included.
The risk of bias was low in 5 trials, unclear in 7 and high in 26.
There were 4 main comparisons
Chlorhexidine (CHX) mouthrinse or gel versus placebo/ usual care;
- High quality evidence (18 RCTs; 2451 participants, 86% adults) that CHX mouthrinse or gel, as part of OHC, reduces the risk of VAP compared to placebo or usual care from 25% to about 19% RR= 0.74 (95%CI; 0.61 – 0.89, P = 0.002, I²= 31%). NNT =17 (95%CI 10 to 33)
- There is no evidence of a difference between CHX and placebo/usual care for:-
- Mortality RR=1.09 (95%CI 0.96 -1.23, P = 0.18, I²= 0%) 15 RCTs, 2163 participants, moderate quality evidence.
- Duration of mechanical ventilation, Mean Difference (MD)= -0.09 days (95%CI; -1.73 to 1.55 days, P = 0.91, I²= 36%) five RCTs, 800 participants, low quality evidence),
- Duration of intensive care unit (ICU) stay MD= 0.21 days (95%CI; -1.48 to 1.89 days, P = 0.81, I²= 9%) six RCTs, 833 participants, moderate quality evidence.
- There is insufficient evidence to determine the effect of CHX on duration of systemic antibiotics, oral health indices, caregivers’ preferences or cost.
- Only two studies reported any adverse effects, and these were mild with similar frequency in CHX and control groups.
toothbrushing versus no toothbrushing;
- The effects of toothbrushing (± antiseptics) on the outcomes of VAP are uncertain RR= 0.69 (95%CI; 0.44 to 1.09, P = 0.11, I 2 = 64%) five RCTs, 889 participants, very low quality evidence.
- Mortality RR= 0.87 (95%CI; 0.70 to 1.09, P = 0.24, I2 = 0%) five RCTs, 889 participants, low quality evidence
- There is insufficient evidence to determine whether toothbrushing affects duration of mechanical ventilation, duration of ICU stay, use of systemic antibiotics, oral health indices, adverse effects, caregivers’ preferences or cost.

powered versus manual toothbrushing; Only one trial (78 participants) compared use of a powered toothbrush with a manual toothbrush, providing insufficient evidence to determine the effect on any of the outcomes of this review.
15 trials compared various other oral care solutions. There is very weak evidence that povidone iodine mouthrinse is more effective than saline/placebo (RR 0.69, 95% CI 0.50 to 0.95, P = 0.02, I2 = 74%, three studies, 356 participants, high risk of bias), and that saline rinse is more effective than saline swab (RR 0.47, 95% CI 0.37 to 0.62, P < 0.001, I2 = 84%, four studies, 488 participants, high risk of bias) in reducing VAP. Due to variation in comparisons and outcomes among trials, there is insufficient evidence concerning the effects of other oral care solutions.

Conclusions

The authors concluded:-

OHC including chlorhexidine mouthwash or gel reduces the risk of developing ventilator-associated pneumonia in critically ill patients from 25% to about 19%. 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 antiseptics and toothbrushing is different from OHC with antiseptics alone, and some weak evidence to suggest that povidone iodine mouthrinse is more effective than saline/placebo, and saline rinse is more effective than saline swab in reducing VAP. There is insufficient evidence to determine whether powered toothbrushing or other oral care solutions are effective in reducing VAP. There is also insufficient evidence to determine whether any of the interventions evaluated in the studies are associated with adverse effects.

Comments

This Cochrane review update now includes 38 RCTs and demonstrates an improvement in the quality of the evidence supporting the use of chlorhexidine mouthwash or gel in reducing the risk of VAP. The number needed to treat for an additional beneficial outcome (NNTB) was 17 (95% CI;10-33) suggesting that for every 17 ventilated patients in intensive care receiving oral care including chlorhexidine one case of VAP would be prevented. As the authors note in their discussion the estimated cost of an episode of VAP is between $10-40,000 compared with a chlorhexidine cost of $3.15 per patient. While the review clearly demonstrated reduction in the risk of VAP there was no evidence of an effect on mortality, duration of mechanical ventilation, or duration of ICU stay.

Links

Primary paper

Hua F, Xie H, Worthington HV, Furness S, Zhang Q, Li C. Oral hygiene care for critically ill patients to prevent ventilator-associated pneumonia. Cochrane Database of Systematic Reviews 2016, Issue 10. Art. No.: CD008367. DOI: 10.1002/14651858.CD008367.pub3.