Ventilator-Associated Pneumonia (VAP)

Causes and Prevalence of VAP

Ventilator Associated Pneumonia (VAP) refers to pneumonia that a patient develops after being subjected to mechanical ventilation through intubation. Ventilator-acquired pneumonia is associated with the increased cost of treatment, high mortality rates, poor patient outcomes, and an extended stay in the hospital. About 27% of critically sick patients have pneumonia, making it the most prevalent nosocomial infection (170). Nosocomial pneumonias that are linked to mechanical ventilation account for 86 percent of all cases. In the United States alone, between 250,000 and 300,000 cases happening every year, with an prevalence rate of about 5 to 10 cases per 1,000 hospitalizations (134, 170). There have been reports of VAP-related deaths ranging from 0% to 50%. Ventilator-associated pneumonia (VAP) is the most common cause of death and serious illness in hospitals when patients are using mechanical ventilators. According to several studies, the prevalence of VAP ranges from 7 percent to 70 percent, with fatality rates ranging from 20 percent to 75 percent. (de Lacerda Vidal et al., 2017). VAP represents a massive problem of mechanical ventilation, accounting for a 10% mortality rate and can surge the number of days a patient spends in  the hospital by about 7–9 days  (Wainer, 2020).

Although a serious complication, recent studies on the predisposing factors of VAP outline that oral health plays a pivotal part in the development or prevention of ventilator-acquired pneumonia (Wainer, 2020). If the nurses fail to adhere to proper hygienic conditions, the patient is likely to develop VAP through inhalation of contaminated air to the lungs causing pneumonia. Thus, the effective oral hygiene should be encouraged among the primary caregivers and other healthcare providers.

VAP can cause colonization of the oropharynx thus there is greater need for nurses to intervene and stop the development of VAP among ventilated patients. The nurses should ensure that oral hygiene is not compromised. Researchers have recommended sanitation methods to clean the tubes or other devices used in the mechanical ventilation (Schiefer, 2021).

The evidence-based practice (EBP) question being investigated through the PICOT
format is: Among hospitalized patients on ventilators, what is the impact of the oral chlorhexidine use on l the rate of ventilator associated pneumonia occurrences, within the initial 30 days of admission? The patient population used (P) are patients on ventilators in long term units and intensive care units. Interventions being looked into (I) is the use of chlorhexidine for oral care and hygiene. The comparison (C) is not needed for this research. The outcomes being assessed (O) is occurrence of ventilator associated pneumonia, and time (T) is over a 30-day period.

In order to search for information regarding the EBP question as stated above three, databases were used. The first one was the Cumulative Index to Nursing & Allied Health Literature (CINAHL) Plus Full Text, the second one from the Ovid Health star and the last one PubMed (see Appendix A). Originally keywords from the EBP question were used to find adequate information from the databased searches. The search of CINAHL database began using “ventilated associated pneumonia prevention or VAP or ventilator acquired pneumonia prevention” as keyword/phrase, 4,508 results were retrieved. After adding and inclusion criteria such as “peer review”, “evidenced based” and “published dates 2017-2022” the result narrowed to 129, in which there was an article found useful. The inclusion and exclusion criteria helped narrow down to the article that was closely related to the desired keywords or phrases. Then the search in the same CINHAL database was repeated with keywords “chlorhexidine” and “ventilator associated pneumonia prevention”, with an inclusion criterion of “published dates 2017-2022” and received 67 results with 12 articles that were useful.

Importance of Oral Hygiene in VAP Prevention

The second database used, Ovid Healthstar, was promising as well. Searching in this database with keywords “chlorhexidine uses for VAP prevention” And “Pneumonia, Ventilator-Associated” yielded over 6,958 searches. When included the inclusion criteria “past five years “and “journal article” the results now narrowed down to 75 which 12 articles were found useful.

The third database used was PubMed. Key words used in this search was “Ventilator-associated pneumonia prevention” which yielded 53 searches and two articles were found useful. In all three searches the inclusion criteria were “publish dates” that where within the last 5 years, “evidence based “and “peer review”. The exclusion criteria used for all three searches where “pediatric or natal”.

Three articles were selected out of the 19 potential articles derived for review and
analysis (see Appendix B). These three articles are chosen according to their ability to answer the EBP question as stated earlier. All these studies are related to oral hygiene and chlorhexidine effectiveness in preventing Ventilator-Acquired Pneumonia. One article was chosen from each of the search database CINAHL, Ovid Healthstar, and PubMed. Each article has its own rank in level of evidence according to The University at Buffalo School of Nursing (UBSON, 2020). The 1st article is a randomized controlled study, which is equivalent of a Level II. The 2nd article is a systematic review which is at an evidence Level 1, with the 3rd article being a qualitative review which is at an evidence level IV. 

The study conducted by Kes, Yildirim, Kuru, Pazarlioglu, Ciftci & Ozdemir, (2021) has three objectives that it intended to achieve. The first one was to compare the effects of the use of 0.12% chlorhexidine (CHX) gluconate in oral care for the prevention of ventilator-associated pneumonia (VAP) and ventilator-associated tracheobronchitis (VAT). The second objective of the study is aimed at comparing a placebo and CHX to determine which had a greater impact on oral health and prevention of colonization with oral microbes (Kes, 2021). It used random sampling to divide 76 participants into the CHX and the placebo group. The third objective was to assess the impact of the solution in oral microbial colonization. Finally, the study focused on assessing the solution’s effect on oral care on general oral health. 

The design employed for the study was a potential, single-blinded, randomized control trial. The design flows from the proposed research problem that required comparing the effectiveness of CHX on oral care. Observational data collection was used in which the researchers collected patient secretions and endotracheal tube aspirate samples on day 0 and day 3 for comparison.

The intervention used in this study was a 0.12 % chlorhexidine for oral care in patients with ventilator-associated respiratory contaminations. The intervention was tested against a placebo made up of sodium bicarbonate.

Chlorhexidine Use for VAP Prevention

The study concluded that CHX gluconate 0.12% used for oral care three times a day is an important intrusion for preventing VAP. CHX effectively reduces microbial colonization in mechanically ventilated patients and could be used to enhance oral health (Kes, 2021). Recommendations made by the author require that nurses should integrate the use of CHX solution into oral care protocols in patients in the ICU.

The strength of the findings was assessed by determining the strengths and the
limitations. VAT and VAP conditions could be diagnosed clinically and microbiologically, which was a major strength of the study (Kes, 2021). However, the study had limitations that hindered the generalizability.

The study falls into level II quality rating of evidence because it randomized control trial. The study demonstrated that using the solution CHX gluconate for oral care three times a day is an efficient intervention for the inhibition of VAP for patients in ICU.

Guler and Turk (2018), conducted a systematic review to evaluate different concentration and frequency of oral chlorhexidine effects on ventilator-associated pneumonia (VAP) and microbial colonization among mechanically ventilated patients. Ten research works were included in the review and had varied sample sizes. On aggregate, the total reviewed sample size was N=916, N=16 being the least and N=260 being the most sample size used on the reviewed studies (Guler & Turk, 2018). Predominantly, two independent reviewers were used to evaluate the quality of the 10 studies through the Cochrane Collaboration’s Risk of Bias (CCRB) Tool (Guler & Turk, 2018). The evaluation was was carried out following the six evaluation domains of the CCRB tool. Resulting differences or disharmony were resolved by means of consensus adjudication

All included studies were random control trials (RCTs) that involved participants with a minimum age of 18 years (Guler & Turk, 2018). All participants were intubated at the time of study and were expected to require intubation for at least between 12 hours to 72 hours. However, the author did not indicate the type of randomization techniques employed on the different reviewed study but noted that most studies demonstrated methodological flaws. The sample sizes used were ideal for the reviewed individual studies based on the study setting and the intervention applied (Guler & Turk, 2018).

The study adopted a systematic review design and followed an organized prescribed flow throughout the article. The study performed an electronic search to identify studies used in the systematic review. Four studies evaluated the effects of 0.2% chlorhexidine, three used 2% chlorhexidine, and two studies used 0.12% chlorhexidine. Only one study used both 0.2% and 2% chlorhexidine for comparison. The rest compared chlorhexidine effects either to; normal saline, placebo dental gel, herbal mouth wash, mouth washing using 0.9% NaCl solution, placebo dental gel or no intervention. The chlorhexidine intervention was applied once a day in one study, twice daily in two studies and four times a day in two studies. The intervention frequency was not mentioned in five studies.

Evidence-Based Practice Question

Results of the systematic review indicate that in two studies, 0.2% chlorhexidine showed increased effectiveness VAP prevention in contrast to normal saline or placebo dental gel. VAP development rate in 0.12% chlorhexidine was found to be less compared to normal saline or oral care without chlorhexidine (Guler & Turk, 2018). Furthermore, the number of applications of chlorhexidine, specifically, twice and four times, showed greater effectiveness VAP prevention (Guler & Turk, 2018). There was not a significant variation in the duration of VAP occurrence in the treatment and control group (Guler & Turk, 2018).

Conclusively, chlorhexidine was observed to have a favourable effect in VAP management among mechanically ventilated patients (Guler & Turk, 2018). Up to 0.2% chlorhexidine concentration showed more effectiveness in the prevention and treatment of VAP, whereas 2% concentration showed more effectiveness in the reduction of microbial colonization at twice daily application. Reviewers suggest further research for a definite conclusion on the frequency and concentration of chlorhexidine.

The review uses a level I evidence level and a high quality of evidence. The article presented a strong systematic review with an organized flow and use of high-quality evidence.

Atashi, Yousefi, Mahjobipoor, & Yazdannik, (2018), conducted a qualitative study to better understand factor(s) that hinder the prevention of ventilator-associated pneumonia in critical care setting. The design follows the hypothesis and literature review because it facilitates the collection of subjective data on the factors that nurses believe hamper the prevention of ventilator-associated pneumonia. The research was carried out in a mixed ICU facility in an Iranian teaching hospital. The authors purposively identified and recruited 23 critical care nurses to participate in the study. The sampling method was appropriate because only nurses who worked in critical care could provide valid responses. The inclusion conditions were willingness to take part in the research and sharing experiences related to ventilator-associated pneumonia. The participants were aged between 20 and 50 years. Four had less years' experience in the critical care setting while 14 and 5 had less than 5 and more than 5 years experiences in a similar setting, respectively. Moreover, 1 was a head nurse and 3 acted as supervisors.

The study focused is on ventilator- associated pneumonia as one of the major risks of patients requiring mechanical breathing support. outstudy findings include that the prevention of ventilator-associated pneumonia is hampered by: Nurses' limited professional knowledge, Inadequate professional responsibility about their conduct, poor job motivation, unfavourable working environment including staff heavy workload and inadequate equipment in the critical care setting (Atashi et al, 2018).

A major strength of the article is that it presents complex data on the factors that affect the prevention of ventilator-associated pneumonia in a simplified way. the authors group the factors into three groups namely minimal professional capacity, unfavourable environmental settings, and unreceptive human resource factors. The article also includes data drawn from nurses working in the critical care environment who have first-hand information on the hindrances to ventilator-associated pneumonia prevention.

Strategy Search Matrix

Before the data was analysed, the authors performed a credibility evaluation through an established audit trial. They sent a sample of the interview questions, responses, and coding to external researchers who verified the entire process (Atashi et al, 2018). The action was imperative in eliminating bias in the study and enhancing the validity of the results.

The study also avoided representation bias by including nurses form different gender and age-groups. Notably, practitioners in the critical care setting may have different experiences due to entrenched age and gender characteristics (Atashi et al, 2018). The inclusion facilitated the collection of highly representative data.

Additionally, since the study assumed a qualitative design, it enabled the researchers to focus of on subjective data before sorting and coding it to derive refined results making this level VI evidence.

The three articles selected to address this EB project involved a randomized control trial, a systematic review and a qualitative descriptive design. They are used to generate highest levels of evidence. The objective of the systematic review was to establish the impact of chlorhexidine at varying frequency and concentration on ventilator-associated pneumonia and microbial colonization in patients who are ventilated mechanically. The objective of the qualitative descriptive design was to establish the viewpoints of Iranian critical care nurses on the hindrances towards the prevention of ventilator-associated pneumonia in intensive care units. The randomized control trial study focused on comparing the impact of the use of 0.12% CHX for oral care in preventing VAT and VAP with the placebo group. It also intended to compare its impact on oral health and oral microbial colonization prevention with the placebo group. The articles had distinct objectives that were all focused on understanding the the impact of the oral chlorhexidine use on the rate of ventilator associated pneumonia occurrences. Considering that there are a lot of past studies focusing on chlorhexidine and ventilator associated pneumonia and thus exclusion criteria was used to determine the most desirable articles.

The findings from the three articles indicated almost similar outcomes with regards to the impact of the oral chlorhexidine use on the rate of ventilator associated pneumonia occurrences. The first article found that CHX effectively reduces microbial colonization in patients ventilated mechanically. The research concluded that CHX gluconate 0.12% used for oral care three times each day is an important prevention intervention. It also emerged that the adoption of 0.12% CHX for oral care can be appropriate for the prevention of VAP and lowering microbial colonization in the patients. The second article established that 0.2% chlorhexidine concentration has increased effectiveness in VAP prevention and treatment, whereas 2% chlorhexidine is highly appropriate in lowering microbial colonization. Application of CHX two times a day seems to be efficient in VAP management and lowering microbial colonization. The review used high quality evidence. A inclusive and detailed search strategy and the assessment of the operational quality of the research works involved was the systematic review strengths. The third article found that a lot of wide differences of hindrances to ventilator associated pneumonia prevention in intensive care units, most of it being related to Nurses limited professional competence. 

Evidence Matrix

Ventilator-associated pneumonia (VAP) prevention was hindered by three key factors: insufficient nursing expertise, unpleasant working circumstances, and ineffective human resource management. Intensive care units face a extensive range of interconnected environmental, personal, and institutional challenges to the control of ventilator-associated pneumonia. As a result of this research, we now know more about the obstacles to preventing ventilator-associated pneumonia. It also emphasized the significance of adequate resources, a sufficient level of staffing, and evidence-based guidelines that are applicable to the environment for preventing effective ventilator-associated pneumonia.

In my opinion, there is a lot of evidence to support the use of chlorhexidine at varying frequency and concentration on ventilator-associated pneumonia and microbial colonization in patients who are ventilated mechanically. The studies have also established the impact and overall effectiveness of using chlorhexidine on ventilator-associated pneumonia and microbial colonization. More evidence also evolves around the possible hindrances to the of ventilator-associated pneumonia prevention. It highlighted the important role that medical practitioners and nurses have in the prevention of ventilator-associated pneumonia.

Conclusion

Ventilator-associated pneumonia (VAP) is a common complication for severely ill individuals. As a result of this nosocomial infection, both morbidity and mortality are anticipated to rise. Mortality and morbidity in patients who spend a long time in the hospital are exacerbated by nosocomial infections, which have a substantial effect on critically sick individuals. Nosocomial infections continue to be common despite numerous preventative strategies. VAP is the most prevalent infection in people who have been intubated.

An open and dry mouth, position of body, endotracheal tube, and probable inhalation of contaminated discharges from the gastrointestinal or oropharynx system are all connected to VAP. Different research has looked at the link between dental health and lung infections. There are a number of different approaches of preventing VAP. Personal protective equipment, hand hygiene, cleaning of the environment and equipment, bed positioning to reduce supineness, subglottic secretion drainage, and dental care are all part of the VAP bundle. All the guidelines agree that dental health is a significant risk factor to regulate towards VAP prevention. Since antimicrobial solution concentrations vary, there is no universally accepted method for applying, frequency, or antimicrobial concentration (0.12 percent up to 2 percent). As a result of a systematic review, chlorhexidine appears to be helpful in reducing the occurrence of nosocomial contaminations and postoperative pneumonia.

References

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