Prevention of Pneumonia due to Ventilator in Critical Patients with U Shape Oral Hygiene Model: A Systematic Review

Pneumonia is a possible infectious complication in the hospital due to the installation of a ventilator. Ventilator-associated Pneumonia (VAP) is an infection that takes a place in the intensive care unit (ICU) in ventilated patients. Almost 90% of infections in hospitals 48 hours after ventilator installation are caused by VAP. Therefore, it has been a significant problem, with increasing ventilator use, and increases duration of stay in the ICU [1]. In America, VAP is the second major source of hospital-acquired infection (HAI) and triggers 25% of infections in the ICU [2]. Meanwhile, in Europe, VAP is a frequent nosocomial infection, ranking second after urinary tract infections [3]. In 76% of cases of VAP, bacteria that accumulate in the oral cavity and lungs are similar [4]. Scannapieco found that streptococcus aureus and pseudomonas aeruginosa were the potential pathogens causing VAP in the oral cavity of ICU patients [5].

There are several ways to prevent VAP infection in ICU patients, such as subglottic suction, toothbrushing, chlorhexidine mouthwash, and herbal mouthwash. Several studies have evaluated the effectiveness of oral decontamination to prevent nosocomial pneumonia. The policy is to prevent VAP through oral hygiene techniques such as subglottic suctioning, cleaning dental plaque, and mechanical interventions such as brushing teeth and rinsing the oral cavity. Besides that, there are also pharmacological interventions, such as antimicrobial agents. The most effective procedure to prevent VAP is to reduce the total of microorganisms in the oral cavity. In a clinical study, Yao et al. found that brushing with clean water two times a day for seven days significantly lowered the cumulative VAP level in the treatment group compared to the control group. They suggest that brushing the teeth twice a day can decrease the risk of VAP infection [6].

Previous research has underlined that oral hygiene methods can reduce VAP risk. The methods included brushing teeth using 0.12% chlorhexidine, swabs to clean the surface of the teeth and gingiva, mouthwash, suction, and combination therapy [6]. This study purposed to critically review the effectiveness of toothbrushing in reducing VAP incidence.

To achieve the aim of the research, the reviewers consider a question: Can toothbrushing reduce ventilator-associated pneumonia (VAP) incidence in ventilated critically ill patients?

This review was created in compliance with the standards for particular items for reporting in systematic reviews. The authors searched PubMed, EBSCO, Science Direct, and ProQuest for randomised controlled trials, observational studies, and meta-analyses published in English from 2011 to 2021. Search terms were oral care, oral hygiene, toothbrushing, and VAP, with a prospecting limit of 10 years for publications, clinical trials, observational studies, and meta-analysis. Two researchers worked independently to find and screen titles and abstracts. A consistent data extraction methodology was utilised to analyse RCTs, observational studies, and meta-analyses according to the full text.

This review aimed to verify whether the use of toothbrushing reduced VAP in critically ill patients. VAP is a serious complication of ventilation. This study has the potential to suggest that oral care in ICU patients affects the improvement of health quality. Eight intervention studies explored the effects of chlorohexidine and toothbrushing, either combined or alone. Studies by Nasiriani et al., Grap et al., Tuon et al., Conley et al., Cutler & Suman, de Lacerda Vidal et al., and Ory et al. were successful in reducing VAP using chlorohexidine and toothbrushing [9, 11, 13–16, 19].

Because the assumptions are based on repeated comparisons, these results should be interpreted cautiously. Our research presents further intriguing indications that could be valuable for future research on the subject. A toothbrush is a tool that can be used to reduce VAP because a toothbrush serves to reduce plaque, bacteria, and mucus in the mouth area. This is in line with the findings of Singh et al., which are in agreement that toothbrushing along with oral care can be an advantage in preventing VAP in patients on mechanical ventilation [21]. To prevent microorganisms from colonising the oral cavity of ventilated critically ill patients in the ICU, oral hygiene should be performed according to proper methods. To avoid the occurrence of VAP, it is necessary to practice good oral hygiene. We identify three studies that mentioned toothbrushing can reduce VAP. According to Ory et al., oral health improved significantly after day 3 of oral treatment when a toothbrush was used in the second period [19]. The risk of VAP was reduced considerably between the two time periods. According to the NMA outcome by Sankaran and Sonis, brushing alone or in combination with a robust antiseptic mouthwash, povidone-iodine, was linked with the highest response rate in critically ill patients in preventing VAP, followed by furacilin and chlorhexidine, serially (0.2%) [10]. It was also shown that brushing with distilled water twice daily can minimise the prevalence of VAP in ICU patients [9]. Singh et al. agree and state that toothbrushing along with oral care can reduce the number of VAP patients, the length of ICU stays, and the ventilator time [21]. Thus, the use of toothbrushing with oral care can reduce mortality in ICU patients. The solution for implementing oral care for mechanically ventilated patients is divided into two sections: mouthwash and moisturiser. The mouthwash solution with chlorhexidine is the most commonly recommended. Chlorhexidine is a bacteriostatic antiseptic and disinfectant that is bacteriostatic against both gram-positive and gram-negative bacteria. Chlorhexidine is an excellent anti-plaque formation agent with a broad spectrum. According to de Lacerda Vidal et al., brushing with 0.12% chlorhexidine gluconate gel decreased VAP prevalence compared to the control group, though the result was not statistically meaningful [16]. Even the Singh et al. results compare patients getting toothbrushing with chlorhexidine mouthwash 0.2% combined with lubrication and getting only the mouthwash reduced VAP in a mechanically ventilated patients [21]. In another opinion, oral hygiene with chlorhexidine reduces the microorganisms in the oral cavity of ICU patients [22]. Patients with critical illness deserve special attention, although this requires extended hospitalisation and more frequent multiple contacts with healthcare providers [23]. Therefore, the use of 0.12% chlorhexidine solution can be a strategy to reduce hospital costs. But the systematic review from Buckley et al. showed mixed results, and the majority failed to demonstrate a significant reduction in the incidence of nosocomial pneumonia with the use of chlorhexidine. However, the cardiothoracic surgery ICU patient population may benefit from its use [24]. While chlorhexidine is safe, it does prompt mucosal irritation and desquamation, and perhaps dry mouth.

We found four studies that mentioned that chlorhexidine can reduce VAP. Chlorhexidine has been demonstrated to be effective in the minimisation of VAP, with 2% chlorhexidine being the most potent [12]. Snyders et al. also noted that there was no indication of a reduction in mortality when chlorhexidine was used [12]. Although 2% chlorhexidine may be the most beneficial in preventing VAP incidence. A study with 5 ml of chlorhexidine for oral care intervention can reduce Clinical Pulmonary Infection Score and VAP in ventilated patients [11]. Significant treatment effects were reported in CPIS for up to 48 hours and up to 72 hours after admission. Methicillin-resistant Staphylococcus aureus (MRSA) was less common in the chlorohexidine group than in the comparison group [13]. Cutler and Sluman revealed a meaningful difference in the incidence of VAP after an oral care change [15]. The enhanced oral care package, which included 1% chlorhexidine gluconate, was correlated to a considerable reduction in VAP.

Oral hygiene is a stand-alone nursing action that has a significant impact on the success of VAP prophylaxis in ventilated patients. Three papers showed that the risk of VAP is reduced when subjects use a toothbrush combined with chlorhexidine. According to Silva et al., a meta-analysis reported that the prevalence of VAP was decreased 24% more in participants who received chlorhexidine in combination with toothbrushing than in those who received only chlorhexidine [20]. De Lacerda Vidal et al. also stated that applying a toothbrush in combination with 0.12% chlorhexidine gel can minimise the prevalence of VAP during the performance period, notwithstanding the fact that the result was not statistically significant. The mean mechanical ventilation period was significantly reduced in the brushing group [16].

In contrast to the discussion above, one study mentioned that toothbrushing cannot decrease the risk of VAP. In the other research by Gu et al., oral care with brushing teeth vs without brushing teeth did not significantly minimise the prevalence of VAP and transform other prominent clinical results in ventilated patients [7]. Hayashida et al. also found that oral bacteria numbers were not reduced by toothbrushing or mucosal washing, but watering of the oral cavity and oropharynx greatly reduced it to 105 cfu/ml [8]. We found that a study conducted by Unahalekhaka et al. mentioned that toothbrushing transmitted possibly pathogenic and antibiotic-resistant bacteria [25]. This research found the mean bacterial population of a toothbrush head was around 10⁴–10⁵ CFU/toothbrush. This was comparable to the total bacteria growth of toothbrushes in healthy patients. They said that the growth of the bacteria did not change over a variety of toothbrush manufacturers [21]. Bacterial growth was also assessed in the grooves of the toothbrush handles that had rubber material. Butts et al. found that smooth grips had fewer bacterial transmissions than grooved grips [26]. According to Lorente et al., there were insignificant variations in baseline characteristics between the two patient groups. The prevalence of VAP did not differ statistically significantly between the groups [18]. Children in the treatment group using chlorohexidine with no possibility of pathogenic microflora in their oropharynx 24 hours after ventilation had lower rates of ventilator-associated pneumonia [17]. In a simple cohort of mechanically ventilated children, the administration of 0.12% chlorhexidine had an insignificant effect on the prevalence of VAP. The study’s use of minimal chlorhexidine, integrated with the children’s characteristics, as well as the presence of multi-resistant Gram-negative organisms, could have affected the outcome [17]. According to one paper, the utilisation of mouthwash cannot reduce VAP because day 4 showed no considerable distinction in the colonisation of dental plaque between the control and study groups. Ventilator-associated pneumonia was identified in 18 individuals. Comparing Listerine or sodium bicarbonate oral care to the comparison group, neither reduced dental plaque growth nor the prevalence of VAP [4].

The American Association of Critical Care Nurses and the Centers for Disease Control and Prevention recommend using chlorhexidine gluconate (0.12%) in oral treatment, and cleaning the patient’s teeth for 3 to 4 minutes to reduce the incidence of VAP [27]. Brushing is an important part of implementing dental care in intubated patients. Most experts recommend a paediatric toothbrush because it has soft bristles and is small enough to access the oral cavity of tracheal intubated patients. For mechanically ventilated patients, the frequency of dental care varies. De Lacerda Vidal et al. suggest that oral treatment be performed every 12 hours [16]. However, it must be done with caution to avoid dislocation of the ETT tube and bleeding. Chlorhexidine has been demonstrated to be healthy; however, it has adverse effects such as inflammation of the mucosal lining [16]. Oral treatment and brushing are important to reduce the incidence of VAP.

We also found that the use of U-shape toothbrush did not appear during the analysis of the study. Most of the studies did not mention the type of toothbrush.

In conclusion, the analysis indicated that among ventilated patients who received toothbrushing, there was a substantial decrease during mechanical ventilation, and also a potential to minimise the risk of VAP. We assumed with caution from a few studies that toothbrushing and chlorhexidine might reduce VAP, but the practice of toothbrushing care should be reconsidered in relation to maintaining it. We also found that the U-shape model was not used in the studies.