Incidence, risk factors, and outcome of ventilator-associated pneumonia

Improving Outcomes in Nosocomial Pneumonia: Recent Evidence and More Challenges

Nosocomial pneumonia (NP) represents a leading nosocomial infection and results in substantial morbidity and cost. Over the last several years, the evidence has evolved which directs our approach to NP. Specifically, the definition of NP and classification of its various subtypes has expanded to capture nuances among various phenotypes of this syndrome. For example, segregating those with hospital-acquired pneumonia (HAP) based on whether they subsequently require mechanical ventilation has been shown to be important. Likewise, newer data indicate the true economic cost of NP and underscore the diverse range of pathogens that can cause NP. Moreover, multidrug-resistant (MDR) bacteria have become a major threat in NP. Fortunately, newer simple preventive strategies have been tested and found to be effective at reducing the incidence of NP. Should prevention fail, a range of new antibiotics have been formally studied in NP and found to be effective. Some of these novel agents have relatively broad ranges of activity and are in vitro active against select MDR organisms. Others, however, are narrower in spectrum and directed against specific problem bacteria. In short, the literature in the field of NP has progressed rapidly, and clinicians require a clear appreciation of these changes so as to improve patient outcomes.

Harnessing of Artificial Intelligence for the Diagnosis and Prevention of Hospital-Acquired Infections: A Systematic Review

Healthcare-associated infections (HAIs) are the most common adverse events in healthcare and constitute a major global public health concern. Surveillance represents the foundation for the effective prevention and control of HAIs, yet conventional surveillance is costly and labor intensive. Artificial intelligence (AI) and machine learning (ML) have the potential to support the development of HAI surveillance algorithms for the understanding of HAI risk factors, the improvement of patient risk stratification as well as the prediction and timely detection and prevention of infections. AI-supported systems have so far been explored for clinical laboratory testing and imaging diagnosis, antimicrobial resistance profiling, antibiotic discovery and prediction-based clinical decision support tools in terms of HAIs. This review aims to provide a comprehensive summary of the current literature on AI applications in the field of HAIs and discuss the future potentials of this emerging technology in infection practice. Following the PRISMA guidelines, this study examined the articles in databases including PubMed and Scopus until November 2023, which were screened based on the inclusion and exclusion criteria, resulting in 162 included articles. By elucidating the advancements in the field, we aim to highlight the potential applications of AI in the field, report related issues and shortcomings and discuss the future directions.

Causative bacteria of ventilator-associated pneumonia in intensive care unit in Bahrain: Prevalence and antibiotics susceptibility pattern

BACKGROUND

Ventilator-associated pneumonia (VAP) is defined as pneumonia that occurs two calendar days following endotracheal intubation or after that. It is the most common infection encountered among intubated patients. VAP incidence showed wide variability between countries.

AIM

To define the VAP incidence in the intensive care unit (ICU) in the central government hospital in Bahrain and review the risk factors and the predominant bacterial pathogens with their antimicrobial susceptibility pattern.

METHODS

The research was a prospective cross-sectional observational study over six months from November 2019 to June 2020. It included adult and adolescent patients (> 14 years old) admitted to the ICU and required intubation and mechanical ventilation. VAP was diagnosed when it occurred after 48 h after endotracheal intubation using the clinical pulmonary infection score, which considers the clinical, laboratory, microbiological, and radiographic evidence.

RESULTS

The total number of adult patients admitted to the ICU who required intubation and mechanical ventilation during the study period was 155. Forty-six patients developed VAP during their ICU stay (29.7%). The calculated VAP rate was 22.14 events per 1000 ventilator days during the study period, with a mean age of 52 years ± 20. Most VAP cases had late-onset VAP with a mean number of ICU days before the development of VAP of 9.96 ± 6.55. Gram-negative contributed to most VAP cases in our unit, with multidrug-resistant Acinetobacter being the most identified pathogen.

CONCLUSION

The reported VAP rate in our ICU was relatively high compared to the international benchmark, which should trigger a vital action plan for reinforcing the implementation of the VAP prevention bundle.

Antimicrobial materials for endotracheal tubes: A review on the last two decades of technological progress

Ventilator-associated pneumonia (VAP) is an unresolved problem in nosocomial settings, remaining consistently associated with a lack of treatment, high mortality, and prolonged hospital stay. The endotracheal tube (ETT) is the major culprit for VAP development owing to its early surface microbial colonization and biofilm formation by multiple pathogens, both critical events for VAP pathogenesis and relapses. To combat this matter, gradual research on antimicrobial ETT surface coating/modification approaches has been made. This review provides an overview of the relevance and implications of the ETT bioburden for VAP pathogenesis and how technological research on antimicrobial materials for ETTs has evolved. Firstly, certain main VAP attributes (definition/categorization; outcomes; economic impact) were outlined, highlighting the issues in defining/diagnosing VAP that often difficult VAP early- and late-onset differentiation, and that generate misinterpretations in VAP surveillance and discrepant outcomes. The central role of the ETT microbial colonization and subsequent biofilm formation as fundamental contributors to VAP pathogenesis was then underscored, in parallel with the uncovering of the polymicrobial ecosystem of VAP-related infections. Secondly, the latest technological developments (reported since 2002) on materials able to endow the ETT surface with active antimicrobial and/or passive antifouling properties were annotated, being further subject to critical scrutiny concerning their potentialities and/or constraints in reducing ETT bioburden and the risk of VAP while retaining/improving the safety of use. Taking those gaps/challenges into consideration, we discussed potential avenues that may assist upcoming advances in the field to tackle VAP rampant rates and improve patient care. STATEMENT OF SIGNIFICANCE: The use of the endotracheal tube (ETT) in patients requiring mechanical ventilation is associated with the development of ventilator-associated pneumonia (VAP). Its rapid surface colonization and biofilm formation are critical events for VAP pathogenesis and relapses. This review provides a comprehensive overview on the relevance/implications of the ETT biofilm in VAP, and on how research on antimicrobial ETT surface coating/modification technology has evolved over the last two decades. Despite significant technological advances, the limited number of gathered reports (46), highlights difficulty in overcoming certain hurdles associated with VAP (e.g., persistent colonization/biofilm formation; mechanical ventilation duration; hospital length of stay; VAP occurrence), which makes this an evolving, complex, and challenging matter. Challenges and opportunities in the field are discussed.

The impact of inspiratory pressure level on prevention of ventilator-associated pneumonia: A double-blind, randomized clinical trial

BACKGROUND

Atelectasis and pneumonia are highly prevalent in patients under mechanical ventilation. Studies indicate that using ventilation with an open lung concept improves recovery, decreases ventilator-related pneumonia, decreases mortality and leads to faster weaning from the ventilator. Therefore, this study investigated the effect of higher airway pressure on ventilator-associated pneumonia.

METHODS

This randomized clinical trial was conducted on 120 patients under mechanical ventilation. The patients were divided into two groups based on ventilator pressure: the control group (pressure level 20) and the intervention group (pressure level 30). Demographic data, disease severity, the incidence of ventilator-associated pneumonia, organ damage, days connected to the ventilator, length of hospitalization in ICU, and mortality were compared between the two groups.

RESULTS

There was no significant difference in demographic data and disease severity between the two groups. The average Clinical Pulmonary Infection Score in the intervention group was significantly lower than the control group (P = 0.02). The intervention group's average Sequential Organ Failure Assessment score was significantly lower than the control group (p = 0.016).

CONCLUSIONS

High-pressure levels can decrease ventilator-associated pneumonia and organ failure. It is recommended that the study be repeated with a larger, more diverse population.

Epidemiology, risk factors and prognosis of ventilator-associated pneumonia during severe COVID-19: Multicenter observational study across 149 European Intensive Care Units

BACKGROUND

COVID-19 patients requiring mechanical ventilation are particularly at risk of developing ventilator-associated pneumonia (VAP). Risk factors and the prognostic impact of developing VAP during critical COVID-19 have not been fully documented.

METHODS

Patients invasively ventilated for at least 48 h from the prospective multicentre COVID-ICU database were included in the analyses. Cause-specific Cox regression models were used to determine factors associated with the occurrence of VAP. Cox-regression multivariable models were used to determine VAP prognosis. Risk factors and the prognostic impact of early vs. late VAP, and Pseudomonas-related vs. non-Pseudomonas-related VAP were also determined.

MAIN FINDINGS

3388 patients were analysed (63 [55-70] years, 75.8% males). VAP occurred in 1523/3388 (45.5%) patients after 7 [5-9] days of ventilation. Identified bacteria were mainly Enterobacteriaceae followed by Staphylococcus aureus and Pseudomonas aeruginosa. VAP risk factors were male gender (Hazard Ratio (HR) 1.26, 95% Confidence Interval [1.09-1.46]), concomitant bacterial pneumonia at ICU admission (HR 1.36 [1.10-1.67]), PaO₂/FiO₂ ratio at intubation (HR 0.99 [0.98-0.99] per 10 mmHg increase), neuromuscular-blocking agents (HR 0.89 [0.76-0.998]), and corticosteroids (HR 1.27 [1.09-1.47]). VAP was associated with 90-mortality (HR 1.34 [1.16-1.55]), predominantly due to late VAP (HR 1.51 [1.26-1.81]). The impact of Pseudomonas-related and non-Pseudomonas-related VAP on mortality was similar.

CONCLUSION

VAP affected almost half of mechanically ventilated COVID-19 patients. Several risk factors have been identified, among which modifiable risk factors deserve further investigation. VAP had a specific negative impact on 90-day mortality, particularly when it occurred between the end of the first week and the third week of ventilation.

Incidence and Predictors of Ventilator-Associated Pneumonia Among Adult Intubated Patients in Bahir Dar Specialized Hospitals, 2021: A Retrospective Follow-Up Study

INTRODUCTION

Ventilator-associated pneumonia refers to pneumonia that happens at least 48 hours after endotracheal intubation. It is associated with high economic costs, longer attributable lengths of stay in the hospital, and high mortality. Therefore, this study aims to determine the incidence and predictors of ventilator-associated pneumonia among adult intensive care unit admitted patients at Bahir Dar Specialized Hospitals.

METHODS

A retrospective follow-up study was conducted among 312 adult intensive care unit admitted patients. A data extraction checklist was used to collect the data. The collected data were coded, cleaned, and entered into EpiData version 3.1 and exported to SPSS version 22 and STATA version 14 for analysis. Descriptive analysis was done by using tables, text and percentages. Bivariable and multivariable log binomial analyses were conducted to identify predictors of ventilator-associated pneumonia. Variables having p-value <0.05 were considered statistically significant.

RESULTS

The study found that 27.9% (95% CI: 23%-33%) of patients developed ventilator-associated pneumonia and the incidence rate of VAP was 45.7 per 1000 ventilator days. Patient's stay more than or equal to 14 days (ARR: 13, 95% CI: 9.3-31) and 7-13 days on MV (ARR: 7.2, 95% CI: 6.2-11), blood transfusion (ARR: 2.8, 95% CI: 1.1-6.9), low GCS (ARR: 2.5, 95% CI: 1.3-5.1), use of corticosteroid (ARR: 2.1, 95% CI: 1.1-4.1), and supine head position (ARR: 8.1, 95% CI: 1.7-40) were identified as independent predictors of ventilator associated pneumonia.

CONCLUSION

Nearly one-fourth of the participants developed ventilator-associated pneumonia. Duration of ventilation, blood transfusion, corticosteroid use, supine head position, and low Glasgow coma scale were significant predictors of ventilator-associated pneumonia.

RISK score for developing ventilator-associated pneumonia in children: The RISVAP study

OBJECTIVES

Ventilator-associated pneumonia (VAP) is the second most common healthcare-associated infection in children. The aim of this study was to determine the risk factors for VAP in children and to create a risk score for developing VAP (RISVAP score).

STUDY DESIGN

It was a prospective observational study, including children who required mechanical ventilation (MV), registered in the multicentre ENVIN-HELICS database from 2014 to 2019. The regression coefficients of each independent risk factor for VAP were used to create the RISVAP score. Each factor scored 0 if it was absent, or, if it was present, an assigned value from 1 to 7, according to the regression coefficient.

RESULTS

A total of 3798 patients were included, 97(2.5%) developing VAP. The independent risk factors for VAP were: female (odds ratio [OR]: 1.642, p = 0.024), MV > 4 days (OR: 26.79, p < 0.001), length in pediatric intensive care unit > 7 days (OR: 11.74, p < 0.001), and previous colonisation (OR: 4.18, p < 0.001). The RISVAP was calculated for each patient as the sum of all the independent risk factors. Three risk groups were obtained: low (0-5 points), intermediate (6-12 points), and high risk for VAP (13-16 points). The area under the curve for the final score was 0.905 (95%confidence interval: 0.888-0.923, p < 0.001).

CONCLUSIONS

The RISVAP is the first risk score for VAP in pediatric populations. Using this predictive score, might be helpful to detect vulnerable patients and therefore implement preventative strategies.

Early prediction of ventilator-associated pneumonia in critical care patients: a machine learning model

Background

This study was performed to develop and validate machine learning models for early detection of ventilator-associated pneumonia (VAP) 24 h before diagnosis, so that VAP patients can receive early intervention and reduce the occurrence of complications.

Patients and methods

This study was based on the MIMIC-III dataset, which was a retrospective cohort. The random forest algorithm was applied to construct a base classifier, and the area under the receiver operating characteristic curve (AUC), sensitivity and specificity of the prediction model were evaluated. Furthermore, We also compare the performance of Clinical Pulmonary Infection Score (CPIS)-based model (threshold value ≥ 3) using the same training and test data sets.

Results

In total, 38,515 ventilation sessions occurred in 61,532 ICU admissions. VAP occurred in 212 of these sessions. We incorporated 42 VAP risk factors at admission and routinely measured the vital characteristics and laboratory results. Five-fold cross-validation was performed to evaluate the model performance, and the model achieved an AUC of 84% in the validation, 74% sensitivity and 71% specificity 24 h after intubation. The AUC of our VAP machine learning model is nearly 25% higher than the CPIS model, and the sensitivity and specificity were also improved by almost 14% and 15%, respectively.

Conclusions

We developed and internally validated an automated model for VAP prediction using the MIMIC-III cohort. The VAP prediction model achieved high performance based on its AUC, sensitivity and specificity, and its performance was superior to that of the CPIS model. External validation and prospective interventional or outcome studies using this prediction model are envisioned as future work.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12890-022-02031-w.

Assessing the Impact of Gender and COPD on the Incidence and Mortality of Hospital-Acquired Pneumonia. A Retrospective Cohort Study Using the Spanish National Discharge Database (2016-2019)

BACKGROUND

We aim to analyze incidence and outcomes of patients hospitalized with hospital-acquired pneumonia (HAP) according to chronic obstructive pulmonary disease (COPD) status and sex in Spain (2016-2019).

METHODS

We conducted a retrospective cohort study using national hospital discharge data of patients ≥40 years with a primary diagnosis of HAP, using the specific diagnostics of non-ventilator (NV)-HAP and ventilator-associated pneumonia (VAP).

RESULTS

We identified 37,029 patients with HAP ((NV)-HAP 87.28%, VAP 12.72%), 13.40% with COPD. HAP incidence increased over time, but only in subjects without COPD (p < 0.001). In women, incidence of HAP and (NV)-HAP was similar regardless of COPD status, but VAP incidence was lower in COPD women (p = 0.007). In men, the incidence of (NV)-HAP was significantly higher in those with COPD, while VAP incidence was lower in COPD men (p < 0.001). The in-hospital mortality (IHM) was similar in men and women with and without COPD. The risk of dying in hospital increased with age, congestive heart failure, cancer, and dialysis among men and women with COPD. Men that underwent surgery had a lower risk of IHM. VAP increased 2.58-times the probability of dying in men and women. Finally, sex was not associated with IHM among COPD patients.

CONCLUSIONS

Incidence of HAP was significantly higher in COPD patients than in those without COPD, at the expense of (NV)-HAP but not of VAP. When stratifying by sex, we found that the difference was caused by men. IHM was similar in COPD and non-COPD patients, with no significant change overtime. In addition, sex was not associated with IHM.

Secondary pneumonias in critically ill patients with COVID-19: risk factors and outcomes

PURPOSE OF REVIEW

The aim of this review is to provide an overview of the current evidence of secondary pneumonias in COVID-19 patients, its incidence, risk factors and impact outcomes.

RECENT FINDINGS

Early studies reported low incidence of hospital-acquired infections in COVID-19 patients. More recent large studies clearly showed that the incidence of secondary pneumonias was markedly high in patients under mechanical ventilation. Duration of mechanical ventilation, acute respiratory distress syndrome, prone position and male sex were identified as risk factors. The adjunctive therapy with steroids and immunomodulators were associated with a higher risk of pneumonia and invasive pulmonary Aspergillosis. Although secondary pneumonias seemed to be associated with poor outcomes, namely mortality, in comparison with influenza, no difference was found in heterogeneity of outcomes. Immunosuppressive therapy has been studied in several observational and randomized trials with conflicting results and the true impact on superinfections, namely secondary pneumonias, has not been properly assessed.

SUMMARY

According to the current evidence, COVID-19 patients are at an increased risk of secondary pneumonias. The impact of immunosuppressive therapies on superinfections is yet to be determined. Further studies are needed to assess the true risk of secondary infections associated with immunosuppressive therapies and to identify preventive strategies.

Systematic review of studies investigating ventilator associated pneumonia diagnostics in intensive care

Background

Ventilator-associated pneumonia (VAP) is an important diagnosis in critical care. VAP research is complicated by the lack of agreed diagnostic criteria and reference standard test criteria. Our aim was to review which reference standard tests are used to evaluate novel index tests for suspected VAP.

Methods

We conducted a comprehensive search using electronic databases and hand reference checks. The Cochrane Library, MEDLINE, CINHAL, EMBASE, and web of science were searched from 2008 until November 2018. All terms related to VAP diagnostics in the intensive treatment unit were used to conduct the search. We adopted a checklist from the critical appraisal skills programme checklist for diagnostic studies to assess the quality of the included studies.

Results

We identified 2441 records, of which 178 were selected for full-text review. Following methodological examination and quality assessment, 44 studies were included in narrative data synthesis. Thirty-two (72.7%) studies utilised a sole microbiological reference standard; the remaining 12 studies utilised a composite reference standard, nine of which included a mandatory microbiological criterion. Histopathological criteria were optional in four studies but mandatory in none.

Conclusions

Nearly all reference standards for VAP used in diagnostic test research required some microbiological confirmation of infection, with BAL culture being the most common reference standard used.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12890-021-01560-0.

Comparative Evaluation of the Role of Nonbronchoscopic and Bronchoscopic Techniques of Distal Airway Sampling for the Diagnosis of Ventilator-Associated Pneumonia

Background:

The diagnosis of ventilator-associated pneumonia (VAP) remains a challenge, with clinicians mainly relying on clinical, radiological, and bacteriologic strategies to manage patients with VAP.

Aims:

To compare the results of non-bronchoscopic and bronchoscopic techniques of distal airway sampling for the diagnosis of VAP.

Settings and Design:

This was a single-center prospective diagnostic accuracy study done in the 14-bedded intensive care unit of a tertiary care referral hospital.

Materials and Methods:

Patients aged ≥18 years, on mechanical ventilation for ≥48 h, and with clinical suspicion of VAP (fever, leukocytosis, and increased tracheal secretions) either on admission or during their stay were included. Every patient underwent both procedures for sample collection, first non-bronchoscopic protected bronchoalveolar lavage (NP-BAL) and then bronchoscopic BAL (B-BAL). Clinical Pulmonary Infection Score (CPIS) was calculated for each patient and the collected samples were evaluated in laboratory using standard microbiological techniques.

Statistical Analysis Used:

The sensitivity, specificity, positive predictive value, and negative predictive value of NP-BAL and B-BAL for the diagnosis of VAP were calculated taking CPIS score of >6 as index test for the diagnosis of VAP.

Results:

Sixty patients were included in the study. Both NP-BAL and B-BAL had concordance with the CPIS at 69.1%. The concordance between NP-BAL and B-BAL was better at 67.6% with a kappa coefficient of 0.064 (P = −0.593). The yield and sensitivity of NP-BAL were comparable to that of B-BAL.

Conclusions:

The blind NP-BAL is an equally effective method of airway sampling and could be a better alternative to replace more invasive B-BAL for microbiologic diagnosis of VAP.

Is COPD associated with increased risk for microaspiration in intubated critically ill patients?

Background

Although COPD patients are at higher risk for aspiration when breathing spontaneously, no information is available on the risk for microaspiration in invasively ventilated COPD patients. The aim of our study was to determine the relationship between COPD and abundant microaspiration in intubated critically ill patients.

Methods

This was a retrospective analysis of prospectively collected data, provided by 3 randomized controlled trials on microaspiration in critically ill patients receiving invasive mechanical ventilation for more than 48 h. Abundant microaspiration was defined as the presence of pepsin and or alpha-amylase at significant levels in tracheal aspirates. In all study patients, pepsin and alpha-amylase were quantitatively measured in all tracheal aspirates collected during a 48-h period. COPD was defined using spirometry criteria.

Results

Among the 515 included patients, 70 (14%) had proven COPD. Pepsin and alpha-amylase were quantitatively measured in 3873 and 3764 tracheal aspirates, respectively. No significant difference was found in abundant microaspiration rate between COPD and non-COPD patients (62 of 70 patients (89%) vs 366 of 445 (82%) patients, p = 0.25). Similarly, no significant difference was found in abundant microaspiration of gastric contents (53% vs 45%, p = 0.28), oropharyngeal secretions (71% vs 71%, p = 0.99), or VAP (19% vs 22%, p = 0.65) rates between the two groups. No significant difference was found between COPD and non-COPD patients in duration of mechanical ventilation, ICU length of stay, or ICU mortality.

Conclusions

Our results suggest that COPD is not associated with increased risk for abundant microaspiration in intubated critically ill patients.

Detection of Carbapenemase and CTX-M Encoding Genes Directly from Bronchoalveolar Lavage Using the CRE and ESBL ELITe MGB Assays: Toward Early and Optimal Antibiotic Therapy Management of Critically Ill Patients with Pneumonia

The detection of carbapenemase extended-spectrum β-lactamase (ESBL)-producing Enterobacterales (EB) has become a major issue among critically ill patients, especially due to their impact on appropriate antimicrobial therapy. This study aimed at evaluating the potential contribution of molecular assays to early optimization of empirical antibiotic therapy among critically ill patients with carbapenemase- and/or CTX-M-producing EB pneumonia. The CRE and ESBL ELITe MGB^® assays were evaluated directly on 197 bronchoalveolar lavage (BAL) samples obtained from 120 patients. Molecular results were then compared to routine culture-based diagnostic results, and a retrospective analysis of the therapeutic antimicrobial management was performed. Among the 197 clinical specimens, bla_KPC-like and bla_CTX-M-like were detected in 20 (10.2%) and 12 (6.1%) specimens belonging to 15 and 11 patients, respectively. Positive predictive value (PPV) and negative predictive value (NPV) of the CRE ELITe MGB Kit were 85% [95% confidence interval [CI]: 64.9-94.6] and 100%, respectively. PPV and NPV of the ESBL ELITe MGB Kit were 75% [95% CI: 49.4-90.2] and 100%, respectively. Retrospective analysis of the therapeutic antimicrobial management at the time of BAL collection showed that in ∼50% of patients with carbapenemase- and CTX-M-producing EB pneumonia empirical antibiotic therapy could have been optimized at least 48-72 hr earlier if positive molecular data had been used. The CRE and ESBL ELITe MGB assays might be an interesting tool for expediting optimization of empirical antibiotic therapy in critically ill patients with pneumonia, depending on local epidemiology of antibiotic resistance, patient risk stratification for EB infection, and availability of an antimicrobial stewardship team.

Ventilator-associated pneumonia surveillance using two methods

BACKGROUND

Ventilator-associated pneumonia surveillance is used as a quality indicator due to concerns that some cases may be preventable and may contribute to mortality. Various surveillance criteria exist for the purposes of national reporting, but a large-scale direct comparison has not been conducted.

METHODS

A prospective cohort study applied two routinely used surveillance criteria for ventilator-associated pneumonia from the European Centre for Disease Control and the American Centers for Disease Control to all patients admitted to two large general intensive care units. Diagnostic rates and concordance amongst diagnostic events were compared.

FINDINGS

A total of 713 at-risk patients were identified during the study period. The European surveillance algorithm returned a rate of 4.6 cases of ventilator-associated pneumonia per 1000 ventilation days (95% confidence interval 3.1-6.6) and the American surveillance system a rate of 5.4 (3.8-7.5). The concordance between diagnostic events was poor (Cohen's Kappa 0.127 (-0.003 to 0.256)).

CONCLUSIONS

The algorithms yield similar rates, but the lack of event concordance reveals the absence of inter-algorithm agreement for diagnosing ventilator-associated pneumonia, potentially undermining surveillance as an indicator of care quality.

Impact of Chronic Obstructive Pulmonary Disease on Incidence, Microbiology and Outcome of Ventilator-Associated Lower Respiratory Tract Infections

Objectives: To determine the impact of chronic obstructive pulmonary disease (COPD) on incidence, microbiology, and outcomes of ventilator-associated lower respiratory tract infections (VA-LRTI). Methods: Planned ancillary analysis of TAVeM study, including 2960 consecutive adult patients who received invasive mechanical ventilation (MV) > 48 h. COPD patients (n = 494) were compared to non-COPD patients (n = 2466). The diagnosis of ventilator-associated tracheobronchitis (VAT) and ventilator-associated pneumonia (VAP) was based on clinical, radiological and quantitative microbiological criteria. Results: No significant difference was found in VAP (12% versus 13%, p = 0.931), or VAT incidence (13% versus 10%, p = 0.093) between COPD and non-COPD patients. Among patients with VA-LRTI, Escherichia coli and Stenotrophomonas maltophilia were significantly more frequent in COPD patients as compared with non-COPD patients. However, COPD had no significant impact on multidrug-resistant bacteria incidence. Appropriate antibiotic treatment was not significantly associated with progression from VAT to VAP among COPD patients who developed VAT, unlike non-COPD patients. Among COPD patients, patients who developed VAT or VAP had significantly longer MV duration (17 days (9–30) or 15 (8–27) versus 7 (4–12), p < 0.001) and intensive care unit (ICU) length of stay (24 (17–39) or 21 (14–40) versus 12 (8–19), p < 0.001) than patients without VA-LRTI. ICU mortality was also higher in COPD patients who developed VAP (44%), but not VAT(38%), as compared to no VA-LRTI (26%, p = 0.006). These worse outcomes associated with VA-LRTI were similar among non-COPD patients. Conclusions: COPD had no significant impact on incidence or outcomes of patients who developed VAP or VAT.

A new scoring system for early diagnosis of ventilator-associated pneumonia: LUPPIS

INTRODUCTION

The Clinical Pulmonary Infection Score (CPIS) based on chest X-ray has been developed to facilitate clinical diagnosis of ventilator-associated pneumonia (VAP); however, this scoring system has a low diagnostic performance. We developed the Lung Ultrasound and Pentraxin-3 Pulmonary Infection Score (LUPPIS) for early diagnosis of VAP and evaluated the performance of this new scoring system.

MATERIAL AND METHODS

In a prospective study of 78 patients with suspected VAP, we assessed the detection accuracy of LUPPIS for pneumonia in adult patients. We also evaluated the diagnostic performance of pentraxin-3 (PTX-3) findings of infection. On the day of the study, lung ultrasound was performed, PTX-3 levels were determined, and an endotracheal aspirate was obtained for Gram staining and culture.

RESULTS

No significant differences were found between groups with respect to age, mechanical ventilation time, APACHE II score, or SOFA score (p > 0.05). Procalcitonin and PTX-3 levels were significantly higher in the VAP (+) group (p < 0.001 and p < 0.001, respectively). The threshold for LUPPIS in differentiating VAP (+) patients from VAP (-) patients was > 7. In predicting VAP, LUPPIS > 7 (sensitivity of 84%, specificity of 87.7%) was superior to CPIS > 6 (sensitivity of 40.1%, specificity of 84.5%).

CONCLUSIONS

LUPPIS appears to provide better results in the prediction of VAP compared to CPIS, and the importance of lung ultrasound and PTX-3 is emphasized, which is a distinctive property of LUPPIS.

Using flexible methods to determine risk factors for ventilator-associated pneumonia in the Netherlands

Seven hospitals participated in the Dutch national surveillance for ventilator-associated pneumonia (VAP) and its risk factors. We analysed time-independent and time-dependent risk factors for VAP using the standard Cox regression and the flexible Weighted Cumulative Effects method (WCE) that evaluates both current and past exposures. The prospective surveillance of intensive care patients aged ≥16 years and ventilated ≥48 hours resulted in the inclusion of 940 primary ventilation periods, comprising 7872 ventilation days. The average VAP incidence density was 10.3/1000 ventilation days. Independent risk factors were age (16–40 years at increased risk: HR 2.42 95% confidence interval 1.07–5.50), COPD (HR 0.19 [0.04–0.78]), current sedation score (higher scores at increased risk), current selective oropharyngeal decontamination (HR 0.19 [0.04–0.91]), jet nebulizer (WCE, decreased risk), intravenous antibiotics for selective decontamination of the digestive tract (ivSDD, WCE, decreased risk), and intravenous antibiotics not for SDD (WCE, decreased risk). The protective effect of ivSDD was afforded for 24 days with a delay of 3 days. For some time-dependent variables, the WCE model was preferable over standard Cox proportional hazard regression. The WCE method can furthermore increase insight into the active time frame and possible delay herein of a time-dependent risk factor.

Risk Factors of Ventilator-Associated Pneumonia in Critically III Patients

Ventilator-associated pneumonia (VAP), a hospital acquired pneumonia that occurs more than 48 h after mechanical ventilation, is a common complication of mechanical ventilation with a high mortality rate. VAP can cause patients to have difficulty weaning off the ventilator and to stay in the hospital longer, which results in a huge financial burden to patients and a huge demand for medical resources. Several strategies, such as drugs including chlorhexidine, β-lactam antibiotics and probiotics, have been used to prevent VAP in clinic. The incidence and the mortality rate of VAP have been decreased with the development of preventative strategies in the past decades, but VAP remains one of the most common causes of nosocomial infections and death in the intensive care unit. Current challenges in the management of VAP involved the lack of a gold standard for diagnosis, the absence of effective preventative strategies, and the rise in antibiotic resistance. Therefore, in order to reduce the incidence of VAP and improve the outcome of patients with mechanical ventilation, it is necessary to clarify the risk factors of VAP for clinical prevention and control of VAP. This paper reviews the international risk factors of VAP occurrence reported in recent years, including patient characteristics, increased mechanical ventilation time and prolonged length of hospital stay, disorders of consciousness, burns, comorbidities, prior antibiotic therapy, invasive operations, gene polymorphisms, and mentions the corresponding preventive measures. Each factor is not only an independent risk factor of VAP, but also has an influence on each other. A better understanding of risk factors for VAP is helpful for predicting the occurrence of VAP, improving the prevention and control of VAP, and reducing the morbidity and mortality rates of patients with VAP.

The relationship between ventilator-associated pneumonia and chronic obstructive pulmonary disease: what is the current evidence?

Chronic obstructive pulmonary disease (COPD) affects approximately 65 million people from which > 25% will require intensive care unit (ICU) admission. Ventilator-associated pneumonia (VAP) is the commonest ICU infection and results in increased morbidity/mortality and costs. The literature on the interaction between COPD and VAP is scarce and controversial. The project aimed to search the literature in order to address the following: (i) Is COPD a risk factor for VAP development? (ii) Does COPD impact the outcome of patients with VAP? (iii) Does VAP development impact the outcome of COPD patients? (iv) Does COPD impact the aetiology of VAP? Current evidence on the topic is controversial. Regarding the impact of VAP on COPD patients, the majority of the existing limited number of studies suggests that VAP development results in higher mortality and longer duration of mechanical ventilation and ICU stay. Also, the majority of the studies exploring the impact of COPD on VAP outcomes suggest that COPD is independently associated with a decrease in survival, although the number of such studies is limited. Regarding the aetiology, Pseudomonas aeruginosa is the most frequent pathogen in VAP patients with COPD. Noteworthy, one study suggests that P. aeruginosa is higher in COPD patients even in the early-onset VAP subgroup. This manuscript provides a comprehensive overview of the available literature on the interaction between COPD and VAP, highlighting the differences and limitations that may have led to controversial results, and it may act as a platform for further research with important clinical implications.

The Value of Supine Chest X-Ray in the Diagnosis of Pneumonia in the Basal Lung Zones

RATIONALE AND OBJECTIVES

Basal lung opacities are frequently observed on supine chest x-ray (SCXR) of intensive care patients, causing insecurity among clinicians and radiologists. We sought to determine the diagnostic accuracy of SCXR for basal pneumonia.

MATERIALS AND METHODS

We identified 172 patients who received both SCXR and computed tomography within 1 hour. Two readers examined the SCXR and rated findings in both basal zones according to the following scale: 0 = "no pneumonia," 1 = "possible pneumonia," 2 = "highly suspected pneumonia." Computed tomography served as standard of reference. Sensitivity, specificity, and positive and negative predictive values (PPV/NPV) were calculated once pooling 0 and 1 as negative and once pooling 1 and 2 as positive finding.

RESULTS

When pooling 0 and 1 as negative, sensitivity was 0.45 (right)/0.38 (left), specificity was 0.94/0.97, PPV was 0.76/0.79, and NPV was 0.81/0.84. When pooling 1 and 2 as positive, sensitivity was 0.80/0.75, specificity was 0.62/0.58, PPV was 0.45/0.35, and NPV was 0.88/0.89. The most common findings in false-positive cases were combined pleural effusions and lower lobe atelectasis.

CONCLUSIONS

Interpreting only highly suspicious basal opacities as pneumonia considerably increases the PPV with almost constant NPV. Clinicians and radiologists should be aware of the limitations of SCXR regarding basal pneumonia.

Respiratory mechanics, ventilator-associated pneumonia and outcomes in intensive care unit

AIM

To evaluate the predictive capability of respiratory mechanics for the development of ventilator-associated pneumonia (VAP) and mortality in the intensive care unit (ICU) of a hospital in southern Brazil.

METHODS

A cohort study was conducted between, involving a sample of 120 individuals. Static measurements of compliance and resistance of the respiratory system in pressure-controlled ventilation (PCV) and volume-controlled ventilation (VCV) modes in the 1^st and 5^th days of hospitalization were performed to monitor respiratory mechanics. The severity of the patients’ illness was quantified by the Acute Physiology and Chronic Health Evaluation II (APACHE II). The diagnosis of VAP was made based on clinical, radiological and laboratory parameters.

RESULTS

The significant associations found for the development of VAP were APACHE II scores above the average (P = 0.016), duration of MV (P = 0.001) and ICU length of stay above the average (P = 0.003), male gender (P = 0.004), and worsening of respiratory resistance in PCV mode (P = 0.010). Age above the average (P < 0.001), low level of oxygenation on day 1 (P = 0.003) and day 5 (P = 0.004) and low lung compliance during VCV on day 1 (P = 0.032) were associated with death as the outcome.

CONCLUSION

The worsening of airway resistance in PCV mode indicated the possibility of early diagnosis of VAP. Low lung compliance during VCV and low oxygenation index were death-related prognostic indicators.

Use of Ventilator Bundle and Staff Education to Decrease Ventilator-Associated Pneumonia in Intensive Care Patients

BACKGROUND

Ventilator-associated pneumonia (VAP), one of the most common hospital-acquired infections, has a high mortality rate.

OBJECTIVES

To evaluate the incidence of VAP in a multidisciplinary intensive care unit and to examine the effects of the implementation of ventilator bundles and staff education on its incidence.

METHODS

A 24-month-long before/after study was conducted, divided into baseline, intervention, and postintervention periods. VAP incidence and rate, the microbiological profile, duration of mechanical ventilation, and length of stay in the intensive care unit were recorded and compared between the periods.

RESULTS

Of 1097 patients evaluated, 362 met the inclusion criteria. The baseline VAP rate was 21.6 per 1000 ventilator days. During the postintervention period, it decreased to 11.6 per 1000 ventilator days (P = .01). Length of stay in the intensive care unit decreased from 36 to 27 days (P = .04), and duration of mechanical ventilation decreased from 26 to 21 days (P = .06).

CONCLUSIONS

VAP incidence was high in a general intensive care unit in a Greek hospital. However, implementation of a ventilator bundle and staff education has decreased both VAP incidence and length of stay in the unit.

Procalcitonin testing to guide antibiotic therapy for the treatment of sepsis in intensive care settings and for suspected bacterial infection in emergency department settings: a systematic review and cost-effectiveness analysis

BACKGROUND

Determination of the presence or absence of bacterial infection is important to guide appropriate therapy and reduce antibiotic exposure. Procalcitonin (PCT) is an inflammatory marker that has been suggested as a marker for bacterial infection.

OBJECTIVES

To assess the clinical effectiveness and cost-effectiveness of adding PCT testing to the information used to guide antibiotic therapy in adults and children (1) with confirmed or highly suspected sepsis in intensive care and (2) presenting to the emergency department (ED) with suspected bacterial infection.

METHODS

Twelve databases were searched to June 2014. Randomised controlled trials were assessed for quality using the Cochrane Risk of Bias tool. Summary relative risks (RRs) and weighted mean differences (WMDs) were estimated using random-effects models. Heterogeneity was assessed visually using forest plots and statistically using the I (2) and Q statistics and investigated through subgroup analysis. The cost-effectiveness of PCT testing in addition to current clinical practice was compared with current clinical practice using a decision tree with a 6 months' time horizon.

RESULTS

Eighteen studies (36 reports) were included in the systematic review. PCT algorithms were associated with reduced antibiotic duration [WMD -3.19 days, 95% confidence interval (CI) -5.44 to -0.95 days, I (2) = 95.2%; four studies], hospital stay (WMD -3.85 days, 95% CI -6.78 to -0.92 days, I (2) = 75.2%; four studies) and a trend towards reduced intensive care unit (ICU) stay (WMD -2.03 days, 95% CI -4.19 to 0.13 days, I (2) = 81.0%; four studies). There were no differences for adverse clinical outcomes. PCT algorithms were associated with a reduction in the proportion of adults (RR 0.77, 95% CI 0.68 to 0.87; seven studies) and children (RR 0.86, 95% CI 0.80 to 0.93) receiving antibiotics, reduced antibiotic duration (two studies). There were no differences for adverse clinical outcomes. All but one of the studies in the ED were conducted in people presenting with respiratory symptoms. Cost-effectiveness: the base-case analyses indicated that PCT testing was cost-saving for (1) adults with confirmed or highly suspected sepsis in an ICU setting; (2) adults with suspected bacterial infection presenting to the ED; and (3) children with suspected bacterial infection presenting to the ED. Cost-savings ranged from £368 to £3268. Moreover, PCT-guided treatment resulted in a small quality-adjusted life-year (QALY) gain (ranging between < 0.001 and 0.005). Cost-effectiveness acceptability curves showed that PCT-guided treatment has a probability of ≥ 84% of being cost-effective for all settings and populations considered (at willingness-to-pay thresholds of £20,000 and £30,000 per QALY).

CONCLUSIONS

The limited available data suggest that PCT testing may be effective and cost-effective when used to guide discontinuation of antibiotics in adults being treated for suspected or confirmed sepsis in ICU settings and initiation of antibiotics in adults presenting to the ED with respiratory symptoms and suspected bacterial infection. However, it is not clear that observed costs and effects are directly attributable to PCT testing, are generalisable outside people presenting with respiratory symptoms (for the ED setting) and would be reproducible in the UK NHS. Further studies are needed to assess the effectiveness of adding PCT algorithms to the information used to guide antibiotic treatment in children with suspected or confirmed sepsis in ICU settings. Additional research is needed to examine whether the outcomes presented in this report are fully generalisable to the UK.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42014010822.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

A labelled-ubiquicidin antimicrobial peptide for immediate in situ optical detection of live bacteria in human alveolar lung tissue

The in situ immediate detection of the presence of bacteria in the distal human lung is of significant clinical utility. Herein we describe the development and optimization of a bacterial binding fragment (UBI29-41) of the antimicrobial peptide, ubiquicidin (UBI), conjugated to an environmentally sensitive fluorophore to enable rapid live bacterial imaging within human lung tissue. UBI29-41 was modified for stability in the presence of human lung bronchoalveolar lavage fluid, for affinity to bacterial membranes and functionality in human lung tissue. The optimized cyclic structure yields an optical molecular Smartprobe for bacterial detection in human lung tissue.

COPD patients with ventilator-associated pneumonia: implications for management

Data on the occurrence and outcome of patients with chronic obstructive pulmonary disease (COPD) and ventilator-associated pneumonia (VAP) are quite limited. The aim of this study was to determine if COPD intensive care unit (ICU) patients have a higher rate of VAP development, different microbiological aetiology or have worse outcomes than other patients without VAP. A secondary analysis of a large prospective, observational study conducted in 27 European ICUs was carried out. Trauma patients were excluded. Of 2082 intubated patients included in the study, 397 (19.1%) had COPD; 79 (19.9%) patients with COPD and 332 (19.7%) patients without COPD developed VAP. ICU mortality increased by 17% (p < 0.05) when COPD patients developed VAP, remaining an independent predictor of mortality [odds ratio (OR) 2.28; 95% confidence interval (CI) 1.35-3.87]. The development of VAP in COPD patients was associated with a median increase of 12 days in the duration of mechanical ventilation and >13 days in ICU stay (p < 0.05). Pseudomonas aeruginosa was more common in VAP when COPD was present (29.1% vs. 18.7%, p = 0.04) and was the most frequent isolate in COPD patients with early-onset VAP, with a frequency 2.5 times higher than in patients without early-onset VAP (33.3% vs. 13.3%, p = 0.03). COPD patients are not more predisposed to VAP than other ICU patients, but if COPD patients develop VAP, they have a worse outcome. Antibiotic coverage for non-fermenters needs to be included in the empiric therapy of all COPD patients, even in early-onset VAP.

Impact of COPD in the outcome of ICU-acquired pneumonia with and without previous intubation

BACKGROUND

COPD seems related to poor outcome in patients with ventilator-associated pneumonia (VAP). However, many patients in the ICU with COPD do not require intubation but can also develop pneumonia in the ICU. We, therefore, compared the characteristics and outcomes of patients with ICU-acquired pneumonia (ICUAP) with and without underlying COPD.

METHODS

We prospectively assessed the characteristics, microbiology, systemic inflammatory response, and survival of 279 consecutive patients with ICUAP clustered according to underlying COPD or not. The primary end point was 90-day survival.

RESULTS

Seventy-one patients (25%) had COPD. The proportion of VAP was less frequent in patients with COPD: 30 (42%) compared with 126 (61%) in patients without COPD (P = .011). Patients with COPD were older; were more frequently men, smokers, and alcohol abusers; and more frequently had previous use of noninvasive ventilation. The rate of microbiologic diagnosis was similar between groups, with a higher rate of Aspergillus species and a lower rate of Enterobacteriaceae in patients with COPD. We found lower levels of IL-6 and IL-8 in patients with COPD without previous intubation. The 90-day mortality was higher in patients with COPD (40 [57%] vs 74 [37%] in patients without COPD, P = .003). Among others, COPD was independently associated with decreased 90-day survival in the overall population (adjusted hazard ratio, 1.94; 95% CI, 1.11-3.40; P = .020); this association was observed only in patients with VAP but not in those without previous intubation.

CONCLUSIONS

COPD was independently associated with decreased 90-day survival in patients with VAP but not in those without previous intubation.

Characteristics of airborne micro-organisms in a neurological intensive care unit: Results from China

OBJECTIVE

To describe the characteristics of airborne micro-organisms in the environment in a Chinese neurological intensive care unit (NICU).

METHODS

This prospective study monitored the air environment in two wards (large and small) of an NICU in a tertiary hospital in China for 12 months, using an LWC-1 centrifugal air sampler. Airborne micro-organisms were identified using standard microbiology techniques.

RESULTS

The mean ± SD number of airborne bacteria was significantly higher in the large ward than in the small ward (200 ± 51 colony-forming units [CFU]/m(3) versus 110 ± 40 CFU/m(3), respectively). In the large ward only, the mean number of airborne bacteria in the autumn was significantly higher than in any of the other three seasons. A total of 279 airborne micro-organisms were identified (large ward: 195; small ward: 84). There was no significant difference in the type and distribution of airborne micro-organisms between the large and small wards. The majority of airborne micro-organisms were Gram-positive cocci in both wards.

CONCLUSION

These findings suggest that the number of airborne micro-organisms was related to the number of patients on the NICU ward.

Diagnosis of ventilator-associated pneumonia: a pilot, exploratory analysis of a new score based on procalcitonin and chest echography

BACKGROUND

To facilitate the clinical diagnosis of ventilator-associated pneumonia (VAP) in the ICU, the Clinical Pulmonary Infection Score (CPIS) has been proposed but has shown a low diagnostic performance in subsequent studies. We propose a new score based on procalcitonin level and chest echography with the aim of improving VAP diagnosis: the Chest Echography and Procalcitonin Pulmonary Infection Score (CEPPIS).

METHODS

This retrospective pilot study recruited patients admitted to the Intensive Care Unit of the Emergency Department, Careggi University Hospital (Florence, Italy), from January 2009 to December 2011. Patients were retrospectively divided into a microbiologically confirmed VAP group or a control group based on diagnosis of VAP and positive tracheal aspirate culture.

RESULTS

A total of 221 patients were included, with 113 in the microbiologically confirmed VAP group and 108 in the control group. A CEPPIS > 5 retrospectively fixed was significantly better in predicting VAP (OR, 23.78; sensitivity, 80.5%; specificity, 85.2%) than a CPIS > 6 (OR, 3.309; sensitivity, 39.8%; specificity, 83.3%). The receiver operating characteristic area under the curve analysis also showed a significantly higher diagnostic value for CEPPIS > 5 than CPIS > 6 (0.829 vs 0.616, respectively; P < .0001).

CONCLUSIONS

In this pilot, exploratory analysis, CEPPIS is effective in predicting VAP. Prospective validation is needed to confirm the potential value of this score to facilitate VAP diagnosis.

Prognostic factors associated with mortality of drug-resistant Acinetobacter baumannii ventilator-associated pneumonia

Background

Ventilator-associated pneumonia (VAP) caused by drug-resistant Acinetobacter baumannii is associated with high mortality in critically ill patients. We identified the prognostic factors of 30-day mortality in patients with VAP caused by drug-resistant A. baumannii and compared survival outcomes among multidrug-resistant (MDR), extensively drug-resistant (XDR) and pandrug-resistant (PDR) A. baumannii VAP.

Methods

A retrospective cohort study was conducted in the Medical Intensive Care Unit at Chiang Mai University Hospital, Thailand. All adult patients diagnosed with A. baumannii VAP between 2005 and 2011 were eligible. Univariable and multivariable Cox’s proportional hazards regression were performed to identify the prognostic factors of 30-day mortality.

Results

A total of 337 patients with microbiologically confirmed A. baumannii VAP were included. The proportion of drug-sensitive (DS), MDR, XDR, and PDR A. baumannii were 9.8%, 21.4%, 65.3%, and 3.6%, respectively. The 30-day mortality rates were 21.2%, 31.9%, 56.8%, and 66.7%, respectively. The independent prognostic factors were SOFA score >5 (hazard ratio (HR) = 3.33, 95% confidence interval (CI) 1.94–5.72, P < 0.001), presence of septic shock (HR = 2.66, 95% CI 1.71–4.12, P < 0.001), Simplified Acute Physiology Score (SAPS) II >45 (HR = 1.58, 95% CI 1.01–2.46, P = 0.045), and inappropriate initial antibiotic treatment (HR = 1.53, 95% CI 1.08–2.20, P = 0.016).

Conclusions

Drug-resistant A. baumannii, particularly XDR and PDR, was associated with a high mortality rate. Septic shock, high SAPS II, high SOFA score, and inappropriate initial antibiotic treatment were independent prognostic factors for 30-day mortality.

Comparing the APACHE II score and IBM-10 score for predicting mortality in patients with ventilator-associated pneumonia

Background:

VAP is defined as pneumonia in patients who use ventilators. The acute physiology and chronic health evaluation (APACHE II) scoring system was originally developed for predicting mortality in patients who were admitted to the intensive care unit. Due to the complexity, a simpler score called IBMP-10 was developed. We designed the study to confirm and further investigate these two methods.

Materials and Methods:

This cross-sectional and analysis-descriptive study was done at the moment of VAP diagnosis on 60 patients in intensive care units. APACHE II and the IBMP-10 scores were calculated. ROC curves were generated to compare the new prediction rule with the APACHE II score. Results were reported as adjusted odds ratios with 95% confidence intervals (CIs). Analyses were performed using SPSS, version 20 and P values of 0.05 were considered to be statistically significant.

Results:

APACHE II Score means (P < 0.001) and IBMP-10 score (P < 0.001) means had significant increase in Non-survivor patient than in patients who survived. APACHE II can be used as a good prediction measure for mortality rate. In IBMP-10 method, specificity and PPV were greater than APACHE II, but in mc-nemar test, there was no significant difference between the two methods (P = 0.55). Both prediction rules had high NPV. In our study, survivors’ prediction value in APACHE II was 46.7%, and in IBMP-10, it was 46.7%.

Conclusion:

IBMP-10, compared to APACHE II, has greater sensitivity, specificity, and AUC to predict mortality. So the consequence of the use of IBMP-10 was better than APACHE II.

Ventilator-associated pneumonia: epidemiology and prognostic indicators of 30-day mortality

We conducted a retrospective cohort study in the medical intensive care unit of Chaing Mai University Hospital to describe the epidemiology of ventilator-associated pneumonia (VAP) and identify prognostic indicators of 30-day VAP mortality. A total of 621 patients diagnosed with VAP between January 2005 and December 2011 were included. The overall 30-day mortality rate was 44.4%. The major causative pathogens were Acinetobacter baumannii (54.3%), Pseudomonas aeruginosa (35.2%), and methicillin-resistant Staphylococcus aureus (15.1%). Most A. baumannii (90.2%) comprised drug-resistant strains. Identified prognostic indicators were co-morbid malignancy (hazard ratio [HR] = 1.60; 95% confidence interval [CI] 1.02-2.42; P = 0.040), septic shock (HR = 2.51; 95% CI, 1.60-4.00; P < 0.001), Simplified Acute Physiology Score II >45 (HR = 1.62; 95% CI, 1.03-2.56; P = 0.041), Sequential Organ Failure Assessment score >5 (HR = 3.40; 95% CI 2.00-5.81; P < 0.001), and delayed inappropriate empirical antibiotic treatment (HR = 2.23; 95% CI, 1.12-4.45; P = 0.022). VAP was associated with high mortality. The major causative pathogen was drug-resistant A. baumannii. Therefore, early detection of VAP by surveillance in mechanically ventilated patients leading to earlier treatment may improve patient outcomes. Guidelines for prescribing appropriate empirical antibiotics to cover drug-resistant bacteria could be established using local epidemiological data.

Global prospective epidemiologic and surveillance study of ventilator-associated pneumonia due to Pseudomonas aeruginosa

OBJECTIVE

To estimate the prevalence of ventilator-associated pneumonia caused by Pseudomonas aeruginosa in patients at risk for ventilator-associated pneumonia and to describe risk factors for P. aeruginosa ventilator-associated pneumonia.

DESIGN

Prospective, observational study.

SETTING

ICUs at 56 sites in 11 countries across four regions: the United States (n = 502 patients), Europe (n = 495), Latin America (n = 500), and Asia Pacific (n = 376).

PATIENTS

Adults intubated and mechanically ventilated for 48 hours to 7 days, inclusive.

INTERVENTIONS

None (local standard of care).

MEASUREMENTS AND MAIN RESULTS

Ventilator-associated pneumonia prevalence as defined by local investigators were 15.6% (293/1,873) globally, 13.5% in the United States, 19.4% in Europe, 13.8% in Latin America, and 16.0% in Asia Pacific (p = 0.04). Corresponding P. aeruginosa ventilator-associated pneumonia prevalences were 4.1%, 3.4%, 4.8%, 4.6%, and 3.2% (p = 0.49). Of 50 patients with P. aeruginosa ventilator-associated pneumonia who underwent surveillance testing, 19 (38%) had prior P. aeruginosa colonization and 31 (62%) did not (odds ratio, 7.99; 95% CI, 4.31-14.71). Of predefined risk factors for multidrug resistance (hereafter, risk factors), the most frequent in all patients were antimicrobial therapy within 90 days (51.9% of enrolled patients) and current hospitalization of more than or equal to 5 days (45.3%). None of these risk factors were significantly associated with P. aeruginosa ventilator-associated pneumonia by multivariate logistic regression. Risk factors associated with prior P. aeruginosa colonization were antimicrobial therapy within 90 days (odds ratio, 0.46; 95% CI, 0.29-0.73) and high proportion of antibiotic resistance in the community or hospital unit (odds ratio, 1.79; 95% CI, 1.14-2.82).

CONCLUSIONS

Our findings suggest that ventilator-associated pneumonia remains a common ICU infection and that P. aeruginosa is one of the most common causative pathogens. The odds of developing P. aeruginosa ventilator-associated pneumonia were eight times higher in patients with prior P. aeruginosa colonization than in uncolonized patients, which in turn was associated with local resistance.

Pulmonary infections in ICU patients without underlying disease on ventilators

BACKGROUND

At present, the use of ventilator support is an important part of treatment in ICU patients. However, aside from its well-known advantages, the use of these devices is also associated with complications, the most important of which is pulmonary infection (PI). PI has a high rate of morbidity and mortality.

OBJECTIVES

This study aimed to evaluate the prevalence of PI in mechanically-ventilated patients and the role that factors, such as age, sex, and duration of intubation, play in this regard.

MATERIALS AND METHODS

This descriptive cross-sectional study evaluated the prevalence of PI in mechanically ventilated patients, with no underlying condition which could compromise their immune system. Age, sex, and duration of intubation were assessed. Data were analyzed using SPSS (version 16) software.

RESULTS

A total of 37 ICU patients on ventilators were evaluated, including 21 males (56.8%) and 16 females (43.2%). The mean age of the patients was 54 ± 19 years (range 19 to 86 years), with a mean age of 52 ± 20 years in men, and 56 ± 18 years in women (P = 0.52). The mean duration of ventilation was 6 ± 4 days (range 2 to 20 days). The mean duration of ventilation was 5 ± 2 days in men, and 6 ± 5 days in women (P = 0.42). A total of 16 patients (43.2%) developed ventilator-associated pneumonia (VAP); of whom, 50% were male and 50% female (P = 0.46). Patients who developed a pulmonary infection had a significantly longer duration of ventilation. The mean duration of ventilation was 8 ± 4 days in patients who had developed VAP, while this duration was 4 ± 2 days in the non-affected patients (P = 0.005). Overall, 17 patients died, and 7 of these deaths were attributed to VAP.

CONCLUSIONS

The prevalence of VAP in this study was approximately 43%, which is relatively high. In total, the percentage of deaths due to VAP among the patients was 18.91%. Duration of ventilator support was significantly correlated with the prevalence of PI.

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.

The epidemiology of ventilator-associated pneumonia in a network of community hospitals: a prospective multicenter study

OBJECTIVE

To describe the epidemiology of ventilator-associated pneumonia (VAP) in community hospitals.

DESIGN AND SETTING

Prospective study in 31 community hospitals from 2007 to 2011.

METHODS

VAP surveillance was performed by infection preventionists using the National Healthcare Safety Network protocol. VAP incidence was reported as number of events per 1,000 ventilator-days. We categorized hospitals into small (<30,000 patient-days/year), medium (30,000-60,000 patient-days/year), and large (>60,000 patient-days/year) groups and compared VAP incidence by hospital size.

RESULTS

he median VAP incidence was 1.4 (interquartile range, 0.4-2.4), and ventilator utilization ratio (VUR) was 0.33 (0.25-0.47). VAP incidence was higher in small hospitals (2.1) than medium (0.85) or large (0.69) hospitals ([Formula: see text]) despite a lower VUR in small hospitals (0.29 vs 0.31 vs 0.44, respectively; [Formula: see text]). The median age of 247 VAP cases was 64 (53-73); 136 (55.1%) were female; 142 (57.5%) were Caucasian; 170 (68.8%) were admitted from home. The length of stay and duration of ventilation were 26 (14-42) and 12 (4-21) days, respectively. The pre- and postinfection hospital stays were 8 (3-13) days and 14 (8-30) days, respectively. Data on outcomes were available in 214 cases (86.6%), and 75 (35.0%) cases died during hospitalization. The top 3 pathogens were methicillin-resistant Staphylococcus aureus (MRSA; [Formula: see text], 27.9%), Pseudomonas species ([Formula: see text], 16.3%), and Klebsiella species ([Formula: see text], 13.3%).

CONCLUSIONS

VAP incidence was inversely associated with size of hospital. VAP in community hospitals was frequently caused by MRSA. Importantly, predictors of VAP incidence in tertiary care hospitals such as VUR may not be predictive in community hospitals with few ventilated patients.