Association between lactate dehydrogenase and ventilator-associated pneumonia risk: an analysis of the MIMIC database 2001-2019

BACKGROUND

Serum lactate dehydrogenase (LDH) is a nonspecific inflammatory biomarker and has been reported to be associated with pneumonia prognosis. This study aimed to evaluate the relationship between LDH levels and ventilator-associated pneumonia (VAP) risk in intensive care unit (ICU) patients.

METHODS

This retrospective cohort study used data from the Multiparameter Intelligent Monitoring in Intensive Care database from 2001 to 2019. ICU patients aged ≥ 18 years and receiving mechanical ventilation were included. LDH levels were analyzed as continuous and categorical variables (< 210, 210-279, 279-390, > 390 IU/L), respectively. Restricted cubic spline (RCS) curves and quartiles were used to categorize LDH levels. Logistic regression and linear regression were utilized to assess the relationship of LDH levels with VAP risk and duration of mechanical ventilation, respectively.

RESULTS

A total of 9,164 patients were enrolled, of which 646 (7.05%) patients developed VAP. High levels of LDH increased the risk of VAP [odds ratio (OR) = 1.15, 95% confidence interval (CI): 1.06-1.24] and LDH levels were positively correlated with the duration of mechanical ventilation [β = 4.49, 95%CI: (3.42, 5.56)]. Moreover, patients with LDH levels of 279-390 IU/L (OR = 1.38, 95%CI: 1.08-1.76) and > 390 IU/L (OR = 1.50, 95%CI: 1.18-1.90) had a higher risk of VAP than patients with LDH levels < 210 IU/L. Patients with LDH levels of 279-390 IU/L [β = 3.84, 95%CI: (0.86, 6.82)] and > 390 IU/L [β = 11.22, 95%CI: (8.21, 14.22)] (vs. <210 IU/L) had a longer duration of mechanical ventilation.

CONCLUSION

Elevated serum LDH levels were related to a higher risk of VAP and longer duration of mechanical ventilation and may be useful for monitoring VAP risk.

Is Zero Ventilator-Associated Pneumonia Achievable? Updated Practical Approaches to Ventilator-Associated Pneumonia Prevention

Ventilator-associated pneumonia (VAP) remains a significant clinical entity with reported incidence rates of 7% to 15%. Given the considerable adverse consequences associated with this infection, VAP prevention became a core measure required in most US hospitals. Many institutions took pride in implementing effective VAP prevention bundles that combined at least head of bed elevation, hand hygiene, chlorhexidine oral care, and subglottic drainage. Spontaneous breathing and awakening trials have also consistently been shown to shorten the duration of mechanical ventilation and secondarily reduce the occurrence of VAP.

The Use of Antibiotics for Ventilator-Associated Pneumonia in the MIMIC-IV Database

Purpose: By analyzing the clinical characteristics, etiological characteristics and commonly used antibiotics of patients with ventilator-associated pneumonia (VAP) in intensive care units (ICUs) in the intensive care database. This study aims to provide guidance information for the clinical rational use of drugs for patients with VAP.

Method: Patients with VAP information were collected from the Medical Information Mart for Intensive Care IV (MIMIC-IV) database, including their sociodemographic characteristics, vital signs, laboratory measurements, complications, microbiology, and antibiotic use. After data processing, the characteristics of the medications used by patients with VAP in ICUs were described using statistical graphs and tables, and experiences were summarized and the reasons were analyzed.

Results: This study included 2,068 patients with VAP. Forty-eight patient characteristics, including demographic indicators, vital signs, biochemical indicators, scores, and comorbidities, were compared between the survival and death groups of VAP patients. Cephalosporins and vancomycin were the most commonly used. Among them, fourth-generation cephalosporin (ForGC) combined with vancomycin was used the most, by 540 patients. First-generati49n cephalosporin (FirGC) combined with vancomycin was associated with the highest survival rate (86.7%). More than 55% of patients were infected with Gram-negative bacteria. However, patients with VAP had fewer resistant strains (&lt;25%). FirGC or ForGC combined with vancomycin had many inflammation-related features that differed significantly from those in patients who did not receive medication.

Conclusion: Understanding antibiotic use, pathogenic bacteria compositions, and the drug resistance rates of patients with VAP can help prevent the occurrence of diseases, contain infections as soon as possible, and promote the recovery of patients.

Pathogenesis-Targeted Preventive Strategies for Multidrug Resistant Ventilator-Associated Pneumonia: A Narrative Review

Ventilator-associated pneumonia (VAP) is the most common hospital-acquired infection in the intensive care unit (ICU), accounting for relevant morbidity and mortality among critically ill patients, especially when caused by multidrug resistant (MDR) organisms. The rising problem of MDR etiologies, which has led to a reduction in treatment options, have increased clinician’s attention to the employment of effective prevention strategies. In this narrative review we summarized the evidence resulting from 27 original articles that were identified through a systematic database search of the last 15 years, focusing on several pathogenesis-targeted strategies which could help preventing MDR-VAP. Oral hygiene with Chlorhexidine (CHX), CHX body washing, selective oral decontamination (SOD) and/or digestive decontamination (SDD), multiple decontamination regimens, probiotics, subglottic secretions drainage (SSD), special cuff material and shape, silver-coated endotracheal tubes (ETTs), universal use of gloves and contact isolation, alcohol-based hand gel, vaporized hydrogen peroxide, and bundles of care have been addressed. The most convincing evidence came from interventions directly addressed against the key factors of MDR-VAP pathogenesis, especially when they are jointly implemented into bundles. Further research, however, is warranted to identify the most effective combination.

A clinical trial of silver-coated and tapered cuff plus supraglottic suctioning endotracheal tubes in preventing ventilator-associated pneumonia

PURPOSE

Novel designs of the endotracheal tube (ETT) are emerged to reduce the risk of ventilator-associated pneumonia (VAP). We evaluated the effect of two different types, namely silver-coated (Bactiguard) and subglottic suctioning (Taperguard) ETTs, on the incidence of VAP in critically-ill patients.

METHODS

A total of 90 patients, mechanically ventilated for >72 h, were randomly assigned to Bactiguard and Taperguard groups. They otherwise received routine care, including VAP prevention measures during their intensive care unit (ICU) stay. Subglottic suctioning was performed in Taperguard group. Statistical analyses were performed using SPSS 25 for iMacs.

RESULTS

Both groups had similar demographics and did not differ in the prevalence of comorbidities and the severity of underlying illness. There was no difference in the frequency of reintubation (P = .565), the duration of ventilation, ICU and total hospital length of stay. VAP developed in 31% of the Bactiguard group and 20% of the Taperguard group (P = .227). Nearly twice the number of patients died in the Bactiguard group compared to the Taperguard group. This difference was not significant either (P = .352).

CONCLUSIONS

The use of Bactiguard or Taperguard ETTs was not associated with any difference in the incidence of VAP or ICU mortality.

Is Zero Ventilator-Associated Pneumonia Achievable?: Practical Approaches to Ventilator-Associated Pneumonia Prevention

Ventilator-associated pneumonia (VAP) remains a significant clinical entity with reported incidence rates of 7% to 15%. Given the considerable adverse consequences associated with this infection, VAP prevention became a core measure required in most US hospitals. Many institutions implemented effective VAP prevention bundles that combined head of bed elevation, hand hygiene, chlorhexidine oral care, and subglottic drainage. More recently, spontaneous breathing and awakening trials have consistently been shown to shorten the duration of mechanical ventilation and secondarily reduce the occurrence of VAP. More recent data question the overall positive impact of prevention bundles, including some of their core component interventions.

Description of Clinical Characteristics of VAP Patients in MIMIC Database

Background: Ventilator-associated pneumonia (VAP) is a common and serious nosocomial infection of intensive-care units (ICUs). Accurate, timely diagnosis enables early VAP patients to receive appropriate therapies and reduce the occurrence of complication. However, so far clinical datas regarding the epidemiology and mortality of VAP are still limited. Medical Information Mart for Intensive Care (MIMIC) database is a free, open and public resource about ICU research database. MIMIC database is a free, open, public database that collects information on more than 40,000 ICU patients who are predominantly white people. Therefore, the purpose of the present study is to observe and describe the clinical characteristics of VAP patients in ICU from the MIMIC database.

Method: A total of 418 patients were enrolled in the study. General information, ventilator use information, microbiology information, antibiotic use information, and some nursing-related information were extracted to describe and analyze the clinical features of VAP patients.

Results: The results of the study showed that patients with one or three pathogens were the most. The main pathogens were YEAST (16.71%), STAPH AUREUS COAG+ (11.63%), Staphylococcus, COAGULASE NEGATIVE (8.68%), GRAM NEGATIVE ROD (S) (6.14%), and Pseudomonas aeruginosa (5.73%). Patients using 4 antibiotics were the most. The top five antibiotics in the largest proportion were synthetic antibacterials (24.66%), peptides (20.13%), cephalosporins (19.60%), penicillins (13.54%), and aminoglycosides (5.27%).

Conclusion: This study summarizes the common pathogens of VAP and the antibiotics commonly used in the treatment of VAP by describing the clinical information of 418 patients with VAP in the MIMIC database. In clinical treatment, we should pay attention to aseptic operation, develop appropriate antibacterial measures, closely monitor the pathogens of VAP infection, and use antibiotics in a timely manner to control the occurrence and development of VAP.

Management of ventilator-associated pneumonia in intensive care units: a mixed methods study assessing barriers and facilitators to guideline adherence

Background

Guidelines from the Infectious Diseases Society of America/The American Thoracic Society (IDSA/ATS) provide recommendations for diagnosis and treatment of ventilator-associated pneumonia (VAP). However, the mere presence of guidelines is rarely sufficient to promote widespread adoption and uptake. Using the Systems Engineering Initiative for Patient Safety (SEIPS) model framework, we undertook a study to understand barriers and facilitators to the adoption of the IDSA/ATS guidelines.

Methods

We conducted surveys and focus group discussions of different health care providers involved in the management of VAP. The setting was medical-surgical ICUs at a tertiary academic hospital and a large multispecialty rural hospital in Wisconsin, USA.

Results

Overall, we found that 55 % of participants indicated that they were aware of the IDSA/ATS guideline. The top ranked barriers to VAP management included: 1) having multiple physician groups managing VAP, 2) variation in VAP management by differing ICU services, 3) physicians and level of training, and 4) renal failure complicating doses of antibiotics.

Facilitators to VAP management included presence of multidisciplinary rounds that include nurses, pharmacist and respiratory therapists, and awareness of the IDSA/ATS guideline. This awareness was associated with receiving effective training on management of VAP, keeping up to date on nosocomial infection literature, and belief that performing a bronchoscopy to diagnose VAP would help with expeditious diagnosis of VAP.

Conclusions

Findings from our study complement existing studies by identifying perceptions of the many different types of healthcare workers in ICU settings. These findings have implications for antibiotic stewardship teams, clinicians, and organizational leaders.

Silver-coated endotracheal tubes for prevention of ventilator-associated pneumonia in critically ill patients

BACKGROUND

Ventilator-associated pneumonia (VAP) is one of the most common nosocomial infections in intubated and mechanically ventilated patients. Endotracheal tubes (ETTs) appear to be an independent risk factor for VAP. Silver-coated ETTs slowly release silver cations. It is these silver ions that appear to have a strong antimicrobial effect. Because of this antimicrobial effect of silver, silver-coated ETTs could be an effective intervention to prevent VAP in people who require mechanical ventilation for 24 hours or longer.

OBJECTIVES

Our primary objective was to investigate whether silver-coated ETTs are effective in reducing the risk of VAP and hospital mortality in comparison with standard non-coated ETTs in people who require mechanical ventilation for 24 hours or longer. Our secondary objective was to ascertain whether silver-coated ETTs are effective in reducing the following clinical outcomes: device-related adverse events, duration of intubation, length of hospital and intensive care unit (ICU) stay, costs, and time to VAP onset.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL; 2014 Issue 10, MEDLINE, EMBASE, EBSCO CINAHL, and reference lists of trials. We contacted corresponding authors for additional information and unpublished studies. We did not impose any restrictions on the basis of date of publication or language. The date of the last search was October 2014.

SELECTION CRITERIA

We included all randomized controlled trials (RCTs) and quasi-randomized trials that evaluated the effects of silver-coated ETTs or a combination of silver with any antimicrobial-coated ETTs with standard non-coated ETTs or with other antimicrobial-coated ETTs in critically ill people who required mechanical ventilation for 24 hours or longer. We also included studies that evaluated the cost-effectiveness of silver-coated ETTs or a combination of silver with any antimicrobial-coated ETTs.

DATA COLLECTION AND ANALYSIS

Two review authors (GT, HV) independently extracted the data and summarized study details from all included studies using the specially designed data extraction form. We used standard methodological procedures expected by The Cochrane Collaboration. We performed meta-analysis for outcomes when possible.

MAIN RESULTS

We found three eligible randomized controlled trials, with a total of 2081 participants. One of the three included studies did not mention the amount of participants and presented no outcome data. The 'Risk of bias' assessment indicated that there was a high risk of detection bias owing to lack of blinding of outcomes assessors, but we assessed all other domains to be at low risk of bias. Trial design and conduct were generally adequate, with the most common areas of weakness in blinding. The majority of participants were included in centres across North America. The mean age of participants ranged from 61 to 64 years, and the mean duration of intubation was between 3.2 and 7.7 days. One trial comparing silver-coated ETTs versus non-coated ETTs showed a statistically significant decrease in VAP in favour of the silver-coated ETT (1 RCT, 1509 participants; 4.8% versus 7.5%, risk ratio (RR) 0.64, 95% confidence interval (CI) 0.43 to 0.96; number needed to treat for an additional beneficial outcome (NNTB) = 37; low-quality evidence). The risk of VAP within 10 days of intubation was significantly lower with the silver-coated ETTs compared with non-coated ETTs (1 RCT, 1509 participants; 3.5% versus 6.7%, RR 0.51, 95% CI 0.31 to 0.82; NNTB = 32; low-quality evidence). Silver-coated ETT was associated with delayed time to VAP occurrence compared with non-coated ETT (1 RCT, 1509 participants; hazard ratio 0.55, 95% CI 0.37 to 0.84). The confidence intervals for the results of the following outcomes did not exclude potentially important differences with either treatment. There were no statistically significant differences between groups in hospital mortality (1 RCT, 1509 participants; 30.4% versus 26.6%, RR 1.09, 95% CI 0.93 to 1.29; low-quality evidence); device-related adverse events (2 RCTs, 2081 participants; RR 0.65, 95% CI 0.37 to 1.16; low-quality evidence); duration of intubation; and length of hospital and ICU stay. We found no clinical studies evaluating the cost-effectiveness of silver-coated ETTs.

AUTHORS' CONCLUSIONS

This review provides limited evidence that silver-coated ETT reduces the risk of VAP, especially during the first 10 days of mechanical ventilation.

Prevention of ventilator-associated pneumonia

Invasive mechanical ventilation (IMV) represents a risk factor for the development of ventilator-associated pneumonia (VAP), which develops at least 48h after admission in patients ventilated through tracheostomy or endotracheal intubation. VAP is the most frequent intensive-care-unit (ICU)-acquired infection among patients receiving IMV. It contributes to an increase in hospital mortality, duration of MV and ICU and length of hospital stay. Therefore, it worsens the condition of the critical patient and increases the total cost of hospitalization. The introduction of preventive measures has become imperative, to ensure control and to reduce the incidence of VAP. Preventive measures focus on modifiable risk factors, mediated by non-pharmacological and pharmacological evidence based strategies recommended by guidelines. These measures are intended to reduce the risk associated with endotracheal intubation and to prevent microaspiration of pathogens to the lower airways.

Ventilator-Associated Pneumonia: When to hold the breath?

Ventilator-associated pneumonia (VAP) is the most common infection in mechanically ventilated patients, and carries the highest mortality. An early diagnosis and definitive management not only reduces the overall mortality, but also brings down the burden of health care to the patient by reducing the cost, length of Intensive Care Unit (ICU) stay, duration of mechanical ventilation, and so on. Out of the various scoring systems, the Clinical Pulmonary Infection Score (CPIS) calculation for VAP has a good sensitivity (72%) and specificity (85%) and the targeted antibiotic therapy in the appropriate dosage is found to be more beneficial than empirical treatment. Although controversies persist on several issues, preventive strategies like head elevation by 30 degrees, cuff pressure monitoring, avoidance of sedatives and muscle relaxants, and so on, have been found to reduce the occurrence of VAP.

Management and prevention of ventilator-associated pneumonia caused by multidrug-resistant pathogens

Ventilator-associated pneumonia (VAP) due to multidrug-resistant (MDR) pathogens is a leading healthcare-associated infection in mechanically ventilated patients. The incidence of VAP due to MDR pathogens has increased significantly in the last decade. Risk factors for VAP due to MDR organisms include advanced age, immunosuppression, broad-spectrum antibiotic exposure, increased severity of illness, previous hospitalization or residence in a chronic care facility and prolonged duration of invasive mechanical ventilation. Methicillin-resistant Staphylococcus aureus and several different species of Gram-negative bacteria can cause MDR VAP. Especially difficult Gram-negative bacteria include Pseudomonas aeruginosa, Acinetobacter baumannii, carbapenemase-producing Enterobacteraciae and extended-spectrum β-lactamase producing bacteria. Proper management includes selecting appropriate antibiotics, optimizing dosing and using timely de-escalation based on antiimicrobial sensitivity data. Evidence-based strategies to prevent VAP that incorporate multidisciplinary staff education and collaboration are essential to reduce the burden of this disease and associated healthcare costs.

Reduced adhesion of Staphylococcus aureus to ZnO/PVC nanocomposites

In hospitals and clinics worldwide, medical device surfaces have become a rapidly growing source of nosocomial infections. In particular, patients requiring mechanical ventilation (and, thus, intubation with an endotracheal tube) for extended lengths of time are faced with a high probability of contracting ventilator-associated pneumonia. Once inserted into the body, the endotracheal tube provides a surface to which bacteria can adhere and form a biofilm (a robust, sticky matrix that provides protection against the host immune system and antibiotic treatment). Adding to the severity of this problem is the spread of bacterial genetic tolerance to antibiotics, in part demonstrated by the recent and significant increase in the prevalence of methicillin-resistant Staphylococcus aureus. To combat these trends, different techniques in biomaterial design must be explored. Recent research has shown that nanomaterials (materials with at least one dimension less than 100 nm) may have the potential to prevent or disrupt bacterial processes that lead to infections. In this study, polyvinyl chloride (PVC) taken from a conventional endotracheal tube was embedded with varying concentrations of zinc oxide (ZnO) nanoparticles. S. aureus biofilms were then grown on these nanocomposite surfaces during a 24-hour culture. Following this, biofilms were removed from the surfaces and the number of colony forming units present was assessed. Bacterial proliferation on the samples embedded with the highest concentration of ZnO nanoparticles was 87% less when compared to the control, indicating that this technique is effective at reducing biofilm formation on PVC surfaces without the use of antibiotics.

Selective decontamination of the digestive tract and selective oropharyngeal decontamination in intensive care unit patients: a cost-effectiveness analysis

OBJECTIVE

To determine costs and effects of selective digestive tract decontamination (SDD) and selective oropharyngeal decontamination (SOD) as compared with standard care (ie, no SDD/SOD (SC)) from a healthcare perspective in Dutch Intensive Care Units (ICUs).

DESIGN

A post hoc analysis of a previously performed cluster-randomised trial (NEJM 2009;360:20).

SETTING

13 Dutch ICUs.

PARTICIPANTS

Patients with ICU-stay of >48 h that received SDD (n=2045), SOD (n=1904) or SC (n=1990).

INTERVENTIONS

SDD or SOD.

PRIMARY AND SECONDARY OUTCOME MEASURES

Effects were based on hospital survival, expressed as crude Life Years Gained (cLYG). The incremental cost-effectiveness ratio (ICER) was calculated, with corresponding cost acceptability curves. Sensitivity analyses were performed for discount rates, costs of SDD, SOD and mechanical ventilation.

RESULTS

Total costs per patient were €41 941 for SC (95% CI €40 184 to €43 698), €40 433 for SOD (95% CI €38 838 to €42 029) and €41 183 for SOD (95% CI €39 408 to €42 958). SOD and SDD resulted in crude LYG of +0.04 and +0.25, respectively, as compared with SC, implying that both SDD and SOD are dominant (ie, cheaper and more beneficial) over SC. In cost-effectiveness acceptability curves probabilities for cost-effectiveness, compared with standard care, ranged from 89% to 93% for SOD and from 63% to 72% for SDD, for acceptable costs for 1 LYG ranging from €0 to €20 000. Sensitivity analysis for mechanical ventilation and discount rates did not change interpretation. Yet, if costs of the topical component of SDD and SOD would increase 40-fold to €400/day and €40/day (maximum values based on free market prices in 2012), the estimated ICER as compared with SC for SDD would be €21 590 per LYG. SOD would remain cost-saving.

CONCLUSIONS

SDD and SOD were both effective and cost-saving in Dutch ICUs.

Use of silver in the prevention and treatment of infections: silver review

BACKGROUND

The use of silver for the treatment of various maladies or to prevent the transmission of infection dates back to at least 4000 b.c.e. Medical applications are documented in the literature throughout the 17th and 18th centuries. The bactericidal activity of silver is well established. Silver nitrate was used topically throughout the 1800 s for the treatment of burns, ulcerations, and infected wounds, and although its use declined after World War II and the advent of antibiotics, Fox revitalized its use in the form of silver sulfadiazine in 1968.

METHOD

Review of the pertinent English-language literature.

RESULTS

Since Fox's work, the use of topical silver to reduce bacterial burden and promote healing has been investigated in the setting of chronic wounds and ulcers, post-operative incision dressings, blood and urinary catheter designs, endotracheal tubes, orthopedic devices, vascular prostheses, and the sewing ring of prosthetic heart valves. The beneficial effects of silver in reducing or preventing infection have been seen in the topical treatment of burns and chronic wounds and in its use as a coating for many medical devices. However, silver has been unsuccessful in certain applications, such as the Silzone heart valve. In other settings, such as orthopedic hardware coatings, its benefit remains unproved.

CONCLUSION

Silver remains a reasonable addition to the armamentarium against infection and has relatively few side effects. However, one should weigh the benefits of silver-containing products against the known side effects and the other options available for the intended purpose when selecting the most appropriate therapy.

Ventilator-associated complications, including infection-related complications: the way forward

Acute respiratory failure represents the most common condition requiring admission to an adult intensive care unit. Ventilator-associated pneumonia (VAP) has been used as a marker of quality for patients with respiratory failure. Hospital-based process-improvement initiatives to prevent VAP have been successfully used. The use of ventilator-associated complications (VACs) has been proposed as an objective marker to assess the quality of care for this patient population. The use of evidence-based bundles targeting the reduction of VACs, as well as the conduct of prospective studies showing that VACs are preventable complications, are reasonable first-steps in addressing this important clinical problem.

Technologic advances in endotracheal tubes for prevention of ventilator-associated pneumonia

Ventilator-associated pneumonia (VAP) is associated with high morbidity, mortality, and costs. Interventions to prevent VAP are a high priority in the care of critically ill patients requiring mechanical ventilation (MV). Multiple interventions are recommended by evidence-based practice guidelines to prevent VAP, but there is a growing interest in those related to the endotracheal tube (ETT) as the main target linked to VAP. Microaspiration and biofilm formation are the two most important mechanisms implicated in the colonization of the tracheal bronchial tree and the development of VAP. Microaspiration occurs when there is distal migration of microorganisms present in the secretions accumulated above the ETT cuff. Biofilm formation has been described as the development of a network of secretions and attached microorganisms that migrate along the ETT cuff polymer and inside the lumen, facilitating the transfer to the sterile bronchial tree. Therefore, our objective was to review the literature related to recent advances in ETT technologies regarding their impact on the control of microaspiration and biofilm formation in patients on MV, and the subsequent impact on VAP.

The value of critical care

The primary focus of this review is on the cost-effectiveness of critical care. The rapid growth in health care expenditures has engendered careful scrutiny of the practice of medicine with regard not only to effectiveness but also to efficiency. This shift necessitates that physicians understand the effectiveness of their interventions and the cost at which this effectiveness is obtained. Cost-effectiveness and cost-utility analyses have become crucial evaluative tools in medicine. Explicit articulation of comparative cost-effectiveness facilitates the allocation of limited resources. Physicians and policy-makers must evaluate such studies with caution, skepticism, and attention to the methods used.

Measures to prevent nosocomial infections during mechanical ventilation

PURPOSE OF REVIEW

Endotracheal intubation and mechanical ventilation are lifesaving measures in critically ill patients. However, these interventions increase the risk of respiratory infections, particularly ventilator-associated pneumonia (VAP). VAP constitutes a serious burden for the healthcare system and worsens the patient's outcomes; thus, several preventive strategies have been implemented. This communication reviews the current knowledge on VAP pathogenesis and the latest preventive measures.

RECENT FINDINGS

Pathogen-laden oropharyngeal secretions leak across the endotracheal tube (ETT) cuff; thus, a continuous control of the internal cuff pressure and cuffs made of polyurethane improve sealing effectiveness and associated risks of infections. Subglottic secretions aspiration prevents VAP, and the latest evidence demonstrated a reduction in the incidence of late-onset VAP. The role of ETT biofilm in the pathogenesis of VAP is not fully elucidated. Nevertheless, antimicrobial-coated ETTs have showed beneficial effects in VAP incidence. Recent experimental evidence has challenged the benefits associated with the use of the semirecumbent position; yet, these findings need to be corroborated in clinical trials. The latest results from trials testing the effects of selective digestive decontamination (SDD) showed beneficial effects on patients' outcomes, but concerns remain regarding the emergence of bacterial resistance, specifically upon digestive tract re-colonization. The use of oropharyngeal decontamination with antiseptics and the use of probiotics are potential alternatives to SDD.

SUMMARY

There is consistent evidence that strategies affecting the primary mechanisms of VAP pathogenesis efficiently reduce the occurrence of the disease. Preventive measures should be implemented grouped into bundles to improve overall efficacy.

Economic aspects of preventing health care-associated infections in the intensive care unit

Infection prevention is critical to providing a high standard of care in the intensive care unit (ICU). Recent focus on eliminating health care–associated infections (HAIs) has met with variable results. Although evidence-based as far as their components, policy-driven bundled HAI prevention interventions have been evaluated in a limited and potentially biased fashion for their effectiveness, and analyses of their cost-effectiveness are lacking. We use ventilator-associated pneumonia as the case study to illustrate the pitfalls and challenges of arriving at the optimal HAI preventive strategies in the ICU.

Strategies for prevention of ventilator-associated pneumonia: bundles, devices, and medications for improved patient outcomes

Ventilator-associated pneumonia is associated with significant patient morbidity, mortality, and increased health care costs. In the current economic climate, it is crucial to implement cost-effective prevention strategies that have proven efficacy. Multiple prevention measures have been proposed by various expert panels. Global strategies have focused on infection control, and reduction of lower airway colonization with bacterial pathogens, intubation, duration of mechanical ventilation, and length of stay in the intensive care unit. Routine use of the Institute for Healthcare Improvement ventilator care bundle is widespread, and has been clearly demonstrated to be an effective method for reducing the incidence of ventilator-associated pneumonia. In this article, we examine specific aspects of the Institute for Healthcare Improvement bundle, better-designed endotracheal tubes, use of antibiotics and probiotics, and treatment of ventilator-associated tracheobronchitis to prevent ventilator-associated pneumonia.

Silver-coated endotracheal tube versus non-coated endotracheal tube for preventing ventilator-associated pneumonia among adults: a systematic review of randomized controlled trials

OBJECTIVE

To compare the effects of using silver-coated endotracheal tube (ETT) versus non-coated ETT on the incidence of ventilator-associated pneumonia (VAP) and mortality in adult patients.

METHOD

We searched MEDLINE, the Cochrane Library, EMBASE, and the Chinese Biomedical Literature Database from inception to June 30, 2011. We also retrieved the reference lists of included studies and reviews. Randomized controlled trials (RCTs) comparing silver-coated ETTs versus non-coated ETTs were included. We pooled the results using a random-effect model and conducted subgroup analyses and sensitivity analyses to address the heterogeneity between studies.

RESULTS

We identified two eligible RCTs with a total of 1630 participants. The studies were of high quality according to Cochrane Collaboration's tool for assessing risk of bias. Compared with non-coated ETTs, silver-coated ETTs resulted in lower incidence of VAP (RR=0.64, 95% CI 0.43 to 0.96), device-related adverse events (RR=0.53, 95% CI 0.32 to 0.88), and microbiologic burden (≥10,000 CFU/mL: 0.64, 0.48 to 0.86; ≥100,000 CFU/mL: 0.62, 0.43 to 0.89). However, there was no significant difference in total mortality (RR=1.14, 95% CI 0.99 to 1.30).

CONCLUSION

The limited evidence from meta-analysis of two RCTs showed that using silver-coated ETTs reduced the incidence of VAP, microbiologic burden, and device-related adverse events among adult patients. Additional rigorous randomized trials are needed to confirm these findings.

Ventilator-associated pneumonia as a model for approaching cost-effectiveness and infection prevention in the ICU

PURPOSE OF REVIEW

Nosocomial infection is a major cause of morbidity and mortality. In the ICU, ventilator-associated pneumonia (VAP) represents the most prevalent and visible hospital-acquired infection (HAI). Although some evidence-based strategies reduce the incidence of VAP, despite a recent policy drive toward zero VAP rates, no evidence supports feasibility of VAP eradication. Furthermore, in the era of resource constraints, cost-effectiveness of various strategies is critical to consider.

RECENT FINDINGS

Recent approaches to VAP prevention conglomerate single maneuvers into bundles. Although the cost-effectiveness of some VAP-preventive interventions, such as continuous subglottic suctioning and silver-coated endotracheal tube, has been evaluated singly, less is known about the investments needed to implement the recommended bundled approaches in the context of their ability to prevent VAP and such important downstream implications as the use of antibiotics and other hospital resources. A well designed model from Australia examining the cost-effectiveness of a catheter-related blood stream infection bundle can serve as robust scaffolding for building a credible value proposition for the VAP bundles.

SUMMARY

Cost-effectiveness of VAP prevention bundles is not known. This is a critical piece of information, particularly as it relates to such important downstream outcomes of VAP prevention as the use of antibiotics and hospital length of stay. Understanding the incremental cost-effectiveness of VAP bundles can help prioritize efforts to minimize the associated morbidity.

The tracheal tube: gateway to ventilator-associated pneumonia

Ventilator-associated pneumonia (VAP) is a major healthcare-associated complication with considerable attributable morbidity, mortality and cost. Inherent design flaws in the standard high-volume low-pressure cuffed tracheal tubes form a major part of the pathogenic mechanism causing VAP. The formation of folds in the inflated cuff leads to microaspiration of pooled oropharyngeal secretions into the trachea, and biofilm formation on the inner surface of the tracheal tube helps to maintain bacterial colonization of the lower airways. Improved design of tracheal tubes with new cuff material and shape have reduced the size and number of these folds, which together with the addition of suction ports above the cuff to drain pooled subglottic secretions leads to reduced aspiration of oropharyngeal secretions. Furthermore, coating tracheal tubes with antibacterial agents reduces biofilm formation and the incidence of VAP. In this Viewpoint article we explore the published data supporting the new tracheal tubes and their potential contribution to VAP prevention strategies. We also propose that it may now be against good medical practice to continue to use a 'standard cuffed tube' given what is already known, and the weight of evidence supporting the use of newer tube designs.

Ventilator-associated pneumonia: update on etiology, prevention, and management

Ventilator-associated pneumonia (VAP) remains one of the most important nosocomial infections in the intensive care unit and has been the focus of much recent research. New evidence on VAP preventive measures includes evidence for the efficacy of changes in endotracheal tube cuff design and materials, drainage of subglottic secretions, saline instillation prior to tracheal suctioning, patient positioning, oral decontamination, aerosolized antibiotics, and probiotic use. In the absence of a clinical reference standard, the diagnosis of VAP remains problematic. Although extensive research on invasive sampling techniques for microbiological confirmation has been conducted, current evidence suggests that endotracheal aspirates are equivalent. Promising new diagnostic methods include non-culture-based microbiological techniques and biomarkers. The treatment of VAP continues to evolve. Shorter antibiotic treatment duration is effective. As well, novel methods of antimicrobial delivery to maximize antibiotic effectiveness and the use of inflammatory biomarkers to guide duration of antibiotic therapy show promise.

Strategies in the prevention of ventilator-associated pneumonia

Ventilator-associated pneumonia (VAP) remains a significant problem in the hospital setting, with very high morbidity, mortality, and cost. We performed an evidence-based review of the literature focusing on clinically relevant pharmacological and nonpharmacological interventions to prevent VAP. Owing to the importance of this condition the implementation of preventive measures is paramount in the care of mechanically ventilated patients. There is evidence that these measures decrease the incidence of VAP and improve outcomes in the intensive care unit. A multidisciplinary approach, continued education, and ventilator protocols ensure the implementation of these measures. Future research will continue to investigate cost/benefit relationships, antibiotic resistance, as well as newer technologies to prevent contamination and aspiration in mechanically ventilated patients.

Do we know how much the evidence-based intervention cost?

In this department, Dr Newhouse highlights hot topics in nursing outcomes, research, and evidence-based practice relevant to the nurse administrator. The goal is to discuss the practical implications for nurse leaders in diverse healthcare settings. Content includes evidence-based projects and decision making, locating measurement tools for quality improvement and safety projects, using outcome measures to evaluate quality, practice implications of administrative research, and exemplars of projects that demonstrate innovative approaches to organizational problems. In this article, the author discusses the importance of measuring evidence-based practice intervention costs, introduces common approaches to measuring cost, and interviews a healthcare economist, Dr Kevin Frick.

New issues and controversies in the prevention of ventilator-associated pneumonia

In the past 2 years, American, Canadian, and European scientific societies have published their new evidence-based guidelines for ventilator-associated pneumonia (VAP) prevention. However, these guidelines did not review some potentially useful strategies, such as the use of an endotracheal tube with an ultrathin cuff membrane, an endotracheal tube with a low-volume/low-pressure cuff, a device for continuous monitoring of the endotracheal tube cuff pressure, a device to remove biofilm from the inner site of the endotracheal tube, and saline instillation before tracheal suctioning. Only a few guidelines analyze the time of tracheostomy, and so no firm recommendations can be made regarding its importance. In addition, the guidelines diverge on the use of heat and moisture exchangers or heated humidifiers and on the use of an endotracheal tube coated with antimicrobial agents. The current review focuses on measures of VAP prevention for which there is no clear recommendation, or the use of which is controversial. A review of the literature suggests that the use of an endotracheal tube with an ultrathin and tapered-shape cuff membrane and coated in antimicrobial agents may reduce the risk of VAP. These features offer an attractive way to optimize the VAP prevention capacity of endotracheal tubes with a lumen for subglottic secretion drainage. We believe that early tracheostomy should be considered, based on the length reduction of mechanical ventilation and intensive care unit stay, reduction of mortality, and on patient comfort, although early tracheostomy has not yet been shown to favorably impact the incidence of VAP. We believed that heat and moisture exchangers should be considered based on the benefits in terms of cost savings. More research is necessary to clarify the role of continuous cuff pressure monitoring, removal of biofilm formation in the endotracheal tubes, and routine saline instillation before tracheal suctioning.

Prevention of ventilator-associated pneumonia in adults

Ventilator-associated pneumonia, broadly defined as pneumonia that develops after 48 hours of intubation, is a common mechanical ventilation complication that causes significant morbidity and mortality in critically ill patients. Prevention strategies are continually evolving to decrease the impact of this serious and costly disease.