Impact of ventilator-associated pneumonia on outcome in patients with COPD

Rebound Inverts the Staphylococcus aureus Bacteremia Prevention Effect of Antibiotic Based Decontamination Interventions in ICU Cohorts with Prolonged Length of Stay

Could rebound explain the paradoxical lack of prevention effect against Staphylococcus aureus blood stream infections (BSIs) with antibiotic-based decontamination intervention (BDI) methods among studies of ICU patients within the literature? Two meta-regression models were applied, each versus the group mean length of stay (LOS). Firstly, the prevention effects against S. aureus BSI [and S. aureus VAP] among 136 studies of antibiotic-BDI versus other interventions were analyzed. Secondly, the S. aureus BSI [and S. aureus VAP] incidence in 268 control and intervention cohorts from studies of antibiotic-BDI versus that among 165 observational cohorts as a benchmark was modelled. In model one, the meta-regression line versus group mean LOS crossed the null, with the antibiotic-BDI prevention effect against S. aureus BSI at mean LOS day 7 (OR 0.45; 0.30 to 0.68) inverted at mean LOS day 20 (OR 1.7; 1.1 to 2.6). In model two, the meta-regression line versus group mean LOS crossed the benchmark line, and the predicted S. aureus BSI incidence for antibiotic-BDI groups was 0.47; 0.09-0.84 percentage points below versus 3.0; 0.12-5.9 above the benchmark in studies with 7 versus 20 days mean LOS, respectively. Rebound within the intervention groups attenuated and inverted the prevention effect of antibiotic-BDI against S. aureus VAP and BSI, respectively. This explains the paradoxical findings.

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.

Relationship between ventilator-associated pneumonia and mortality in COVID-19 patients: a planned ancillary analysis of the coVAPid cohort

Background

Patients with SARS-CoV-2 infection are at higher risk for ventilator-associated pneumonia (VAP). No study has evaluated the relationship between VAP and mortality in this population, or compared this relationship between SARS-CoV-2 patients and other populations. The main objective of our study was to determine the relationship between VAP and mortality in SARS-CoV-2 patients.

Methods

Planned ancillary analysis of a multicenter retrospective European cohort. VAP was diagnosed using clinical, radiological and quantitative microbiological criteria. Univariable and multivariable marginal Cox’s regression models, with cause-specific hazard for duration of mechanical ventilation and ICU stay, were used to compare outcomes between study groups. Extubation, and ICU discharge alive were considered as events of interest, and mortality as competing event.

Findings

Of 1576 included patients, 568 were SARS-CoV-2 pneumonia, 482 influenza pneumonia, and 526 no evidence of viral infection at ICU admission. VAP was associated with significantly higher risk for 28-day mortality in SARS-CoV-2 group (adjusted HR 1.65 (95% CI 1.11–2.46), p = 0.013), but not in influenza (1.74 (0.99–3.06), p = 0.052), or no viral infection groups (1.13 (0.68–1.86), p = 0.63). VAP was associated with significantly longer duration of mechanical ventilation in the SARS-CoV-2 group, but not in the influenza or no viral infection groups. VAP was associated with significantly longer duration of ICU stay in the 3 study groups. No significant difference was found in heterogeneity of outcomes related to VAP between the 3 groups, suggesting that the impact of VAP on mortality was not different between study groups.

Interpretation

VAP was associated with significantly increased 28-day mortality rate in SARS-CoV-2 patients. However, SARS-CoV-2 pneumonia, as compared to influenza pneumonia or no viral infection, did not significantly modify the relationship between VAP and 28-day mortality.

Clinical trial registration

The study was registered at ClinicalTrials.gov, number NCT04359693.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13054-021-03588-4.

Protocol for an international, multicentre, prospective, observational study of nosocomial pneumonia in intensive care units: the PneumoINSPIRE study

Background: Nosocomial pneumonia in the critical care setting is associated with increased morbidity, significant crude mortality rates and high health care costs. Ventilator-associated pneumonia represents about 80% of nosocomial pneumonia cases in intensive care units (ICUs). Wide variance in incidence of nosocomial pneumonia and diagnostic techniques used has been reported, while successful treatment remains complex and a matter of debate. Objective: To describe the epidemiology, diagnostic strategies and treatment modalities for nosocomial pneumonia in contemporary ICU settings across multiple countries around the world. Design, setting and patients: PneumoINSPIRE is a large, multinational, prospective cohort study of adult ICU patients diagnosed with nosocomial pneumonia. Participating ICUs from at least 20 countries will collect data on 10 or more consecutive ICU patients with nosocomial pneumonia. Site-specific information, including hospital policies on antibiotic therapy, will be recorded along with patient-specific data. Variables that will be explored include: aetiology and antimicrobial resistance patterns, treatment-related parameters (including time to initiation of antibiotic therapy, and empirical antibiotic choice, dose and escalation or de-escalation), pneumonia resolution, ICU and hospital mortality, and risk factors for unfavourable outcomes. The concordance of ventilator-associated pneumonia diagnosis with accepted definitions will also be assessed. Results and conclusions: PneumoINSPIRE will provide valuable information on current diagnostic and management practices relating to ICU nosocomial pneumonia, and identify research priorities in the field. Trial registration:ClinicalTrials.gov identifier NCT02793141.

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.

Effect of chronic obstructive pulmonary disease combined with ventilator-associated pneumonia on patient outcomes: A systematic review and meta-analysis

The purpose of the present systematic review and meta-analysis was to uncover whether chronic obstructive pulmonary disease (COPD) as a co-morbidity influences outcomes of patients with ventilator-associated pneumonia (VAP) compared to VAP alone and whether the development of VAP in patients with COPD is associated with poor outcome in comparison to COPD alone. An electronic search of the PubMed, Embase, Scopus, BioMed Central, CENTRAL and Google scholar databases for all types of studies assessing the influence of COPD on outcomes of patients with VAP and vice versa was performed. A total of 7 studies were included. Of these, 3 studies assessed the impact of COPD on outcomes of patients with VAP. Meta-analysis indicated that the presence of COPD significantly increased the mortality of patients with VAP [risk ratio (RR): 1.37, 95% CI: 1.14-1.65, I²=3%, P=0.007]. The analysis failed to demonstrate any significant effect of COPD on the duration of mechanical ventilation in patients with VAP [mean difference (MD): 2.37, 95% CI: -5.77 to 10.50, I²=38%, P=0.57]. However, the duration of the intensive care unit (ICU) stay was significantly longer in patients with COPD and VAP as compared with that of patients with VAP without COPD (MD: 5.53, 95% CI: 0.73-10.33, I²=0%, P=0.02). A total of 4 studies assessed the impact of VAP on outcomes of patients with COPD. Meta-analysis indicated that the presence of VAP significantly increased mortality of patients with COPD (RR: 1.52, 95% CI: 1.08-2.12, I²=71%, P=0.02). Pooled analysis indicated that the presence of VAP in patients with COPD significantly increased the duration of mechanical ventilation (MD: 13.73, 95% CI: 7.86-19.61, I²=92%, P<0.00001) and the duration of the ICU stay as compared to patients with COPD but without VAP (MD: 17.36, 95% CI: 9.55-25.17, I²=90%, P<0.0001). To conclude, within the limitations of the study, the present results indicated that the combination of COPD and VAP significantly increased patient mortality and the duration of ICU stay. The development of VAP in patients with COPD also significantly increased the duration of mechanical ventilation. Further case-matched studies are required to assess the influence of the severity of COPD in combination with VAP on patient outcomes.

Hospital admissions for community-acquired, ventilator-associated and nonventilator hospital-acquired pneumonia in COPD patients in Spain (2016-2017)

BACKGROUND

To examine the incidence, characteristics and outcomes of community-acquired pneumonia (CAP), ventilator-associated pneumonia (VAP) and nonventilator hospital-acquired pneumonia (NV-HAP) in patients with or without COPD; compare in-hospital outcomes; and identify factors associated with in-hospital mortality (IHM) for pneumonia.

METHODS

We carried out a retrospective observational study using the hospital discharge records from 2016-17 of the Spanish National Health System. Propensity score matching was used for data analysis.

RESULTS

We found 245,905 patients (≥40 years) with pneumonia; we identified CAP in 228,139 patients (19.85% with COPD), VAP in 2,771 patients (8.55% with COPD) and NV-HAP in 14,995 patients (14.17% with COPD). The incidence for the three types of pneumonia was higher in COPD patients (CAP: incidence rate ratio (IRR) 2.23, 95% CI 2.21-2.26; VAP: IRR 1.25, 95% CI 1.08-1.42; and NV-HAP: IRR 1.55, 95% CI 1.48-1.63). The IHM for CAP was 10.35% in COPD patients and 12.91% in the controls (p<0.001). In patients with VAP and NV-HAP, IHM was not significantly different between those with and without COPD (43.88% vs. 41.77%;p=0.643 and 29.21% vs. 30.57%;p=0.331, respectively). Factors associated with IHM for all types of pneumonia analyzed in COPD patients were older age and receiving dialysis.

CONCLUSIONS

The incidence of hospitalizations for all types of pneumonia was significantly higher in COPD patients than in the non-COPD population. In contrast, IHM was significantly lower among COPD patients with CAP than among matched non-COPD patients. Higher mortality rates in COPD patients with any pneumonia type were associated with increasing age and receiving dialysis.

Epigenetic Modifications and Therapy in Chronic Obstructive Pulmonary Disease (COPD): An Update Review

Chronic obstructive pulmonary disease (COPD) that is one of the most prevalent chronic adult diseases and the third leading cause of fatality until 2020. Elastase/anti-elastase hypothesis, chronic inflammation, apoptosis, oxidant-antioxidant balance and infective repair cause pathogenesis of COPD are among the factors at play. Epigenetic changes are post-translational modifications in histone proteins and DNA such as methylation and acetylation as well as dysregulation of miRNAs expression. In this update review, we have examined recent studies on the upregulation or downregulation of methylation in different genes associated with COPD. Dysregulation of HDAC activity which is caused by some factors and miRNAs plays a key role in the suppression and reduction of COPD development. Also, some therapeutic approaches are proposed against COPD by targeting HDAC2 and miRNAs, which have therapeutic effects.

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.

Predictors and microbiology of ventilator-associated pneumonia among patients with exacerbation of chronic obstructive pulmonary disease

BACKGROUND

Understanding the risk factors and microbiology of ventilator-associated pneumonia (VAP) among patients with chronic obstructive pulmonary disease (COPD) is important for the application of preventive and therapeutic interventions. Therefore, this study was planned to assess the clinical predictors and microbiological features of VAP among COPD patients.

MATERIALS AND METHODS

This prospective study involved patients with exacerbation of COPD who required mechanical ventilation and admitted in respiratory intensive care unit at a tertiary care teaching hospital. Various baseline demographic and clinical features were compared between patients with VAP and without VAP. Univariate and multivariable analyses were done to assess the impact of demographic and clinical features on the development of VAP.

RESULTS

The study included 100 intubated patients with age (mean ± standard deviation [SD]) of 62.45 ± 8.32 years, duration (median) of COPD of 6 years, and Acute Physiology, Age, and Chronic Health Evaluation score (mean ± SD) of 18.60 ± 4.30. In this cohort, 17 patients developed VAP. Multivariable analysis showed that Sequential Organ Failure Assessment (SOFA) score at admission, re-intubation, and history of previous hospitalization were independent predictors of VAP with odds ratio (95% confidence interval) of 2.70 (1.24, 5.63; P = 0.012), 66.96 (4.86, 922.72; P = 0.002), and 35.92 (2.84, 454.63; P = 0.006), respectively. Acinetobacter baumannii was the most frequent organism (n = 8; 47%), followed by Klebsiella pneumoniae (n = 5; 29%), Pseudomonas aeruginosa (n = 1; 6%), and Enterobacter spp. (n = 1; 6%). All organisms were multidrug resistant (MDR).

CONCLUSIONS

SOFA score at admission, re-intubation, and history of previous hospitalization were independent predictors of VAP. Antimicrobial therapy for VAP should cover MDR Gram-negative organisms.

Host-pathogen interaction during mechanical ventilation: systemic or compartmentalized response?

Patients admitted to the intensive care unit (ICU) often require invasive mechanical ventilation. Ventilator-associated lower respiratory tract infections (VA-LRTI), either ventilator-associated tracheobronchitis (VAT) or ventilator-associated pneumonia (VAP), are the most common complication among this patient cohort. VAT and VAP are currently diagnosed and treated as separate entities, viewed as binary disease elements despite an inherent subjectivity in distinguishing them clinically. This paper describes a new approach to pulmonary infections in critically ill patients. Our conjecture is that the host-pathogen interaction during mechanical ventilation determines a local compartmentalized or systemic de-compartmentalized response, based on host immunity and inflammation, and the pathogenic potential of the infecting organism. This compartmentalized or de-compartmentalized response establishes disease severity along a continuum of colonization, VAT or VAP. This change in approach is underpinned by the dissemination hypothesis, which acknowledges the role of immune and inflammatory systems in determining host response to pathogenic organisms in the lower respiratory tract. Those with intact immune and inflammatory pathways may limit infection to a compartmentalized VAT, while immunosuppressed mechanically ventilated patients are at greater risk of a de-compartmentalized VAP. Taking this model from the realm of theory to the bedside will require a greater understanding of inflammatory and immune pathways, and the development of novel disease-specific biomarkers and diagnostic techniques. Advances will lead to early initiation of optimal bespoke antimicrobial therapy, where the intensity and duration of therapy are tailored to clinical, immune and biomarker response. This approach will benefit towards a personalized treatment.

How Can We Distinguish Ventilator-Associated Tracheobronchitis from Pneumonia?

Ventilator-associated tracheobronchitis (VAT) might represent an intermediate process between lower respiratory tract colonization and ventilator-associated pneumonia (VAP), or even a less severe spectrum of VAP. There is an urgent need for new concepts in the arena of ventilator-associated lower respiratory tract infections. Ideally, the gold standard of care is based on prevention rather than treatment of respiratory infection. However, despite numerous and sometimes imaginative efforts to validate the benefit of these measures, most clinicians now accept that currently available measures have failed to eradicate VAP. Stopping the progression from VAT to VAP could improve patient outcomes.

Risk factors of ventilator-associated pneumonia in elderly patients receiving mechanical ventilation

Purpose: The aim of this study was to verify the potential risk factors of ventilator-associated pneumonia (VAP) in elderly Chinese patients receiving mechanical ventilation (MV). The secondary aim of this study was to present logistical regression prediction models of VAP occurrence in elderly Chinese patients receiving MV. Methods: Patients (aged 80 years or above) receiving MV for ≥48 h were enrolled from the Chinese People's Liberation Army (PLA) General Hospital from January 2011 to December 2015. A chi-squared test and Mann-Whitney U-test were used to compare the data between participants with VAP and without VAP. Univariate logistic regression models were performed to explore the relationship between risk factors and VAP. Results: A total of 901 patients were included in the study, of which 156 were diagnosed as VAP (17.3%). The incidence density of VAP was 4.25/1,000 ventilator days. Logistic regression analysis showed that the independent risk factors for elderly patients with VAP were COPD (OR =1.526, P < 0.05), intensive care unit (ICU) admission (OR=1.947, P < 0.01), the MV methods (P < 0.023), the number of antibiotics administered (OR=4.947, P < 0.01), the number of central venous catheters (OR=1.809, P < 0.05), the duration of indwelling urinary catheter (OR=1.805, P < 0.01) and the use of corticosteroids prior to MV (OR=1.618, P < 0.05). Logistic regression prediction model of VAP occurrence in the Chinese elderly patients with mechanical ventilation:L o g i t   P = - 6 . 468 + 0 . 423 X 1 + 0 . 666 X 2 + 0 . 871 X 3 + - 0 . 501 X 5 + 0 . 122 X 6 + 0 . 593 X 7 + 0 . 590 X 8 + 1 . 599 X 9 . Conclusion: VAP occurrence is associated with a variety of controllable factors including the MV methods and the number of antibiotics administered. A model was established to predict VAP occurrence so that high-risk patients could be identified as early as possible.

One functional variant in the 3'-untranslated region of TLR4 is associated with the elevated risk of ventilator-associated pneumonia in the patients with chronic obstructive pulmonary disease

The aim of this study was to identify the association polymorphism (rs11536889) in the 3'-untranslated region (3'-UTR) of Toll-like receptors 4 (TLR4) and the risk for ventilator-associated pneumonia (VAP). miRNA database online and luciferase assays were used to validate TLR4 as the target gene of miR-1236. Enzyme-linked immunosorbent assay analysis and western blot were used to analyze the level of TLR4 in different genotype groups. In the present study, miR-1236 was predicted to bind to the rs11536889 G allele rather than the rs11536889 C allele, which was further confirmed by the luciferase activity suppressed by a fragment of 3'-UTR containing the rs11536889 G allele induced by lipopolysaccharide (LPS) and interleukin-6 (IL-6). Bronchial epithelial cells isolated from participants genotyped as GG, GC, and CC, with no remarkable difference in TLR4 messenger RNA (mRNA) levels were observed among these genotype groups. After stimulating by LPS, a TLR4 ligand, the CC-genotyped cells expressed higher levels of IL-8, IL-6, and tumor necrosis factor alpha (TNF-α) on their surfaces than cells with the other genotypes. Finally, the western blot analysis results showed that the expression level of IL-8, IL-6, and TNF-α protein was much higher in the CC group than the GC and GG groups subsequent to stimulation by LPS, and the IL-8, IL-6, and TNF-α protein levels in the GC were grouped much lower compared with the GG group. These findings indicated the regulatory association of miR-1236 with TLR4 and the abnormal expression of TLR4 caused by the presence of rs11536889 in the 3'-UTR of mRNA, which interfere with its interaction with the miR-1236, contributing to the risk of 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.

Relationship between digestive tract colonization and subsequent ventilator-associated pneumonia related to ESBL-producing Enterobacteriaceae

BACKGROUND

Ventilator-associated pneumonia (VAP) is the most common ICU-acquired infection. Recently, the incidence of extended-spectrum beta-lactamase producing Enterobacteriaceae (ESBLE) has substantially increased in critically ill patients. Identifying patients at risk for VAP related to ESBLE could be helpful to improve the rate of appropriate initial antibiotic treatment, and to reduce unnecessary exposure to carbapenems. The primary objective was to identify risk factors for VAP related to ESBLE. Secondary objective was to determine the impact of ESBLE on outcome in VAP patients.

METHODS

This retrospective study was conducted in a single mixed intensive care unit (ICU), during a 4-year period. All patients with confirmed VAP were included. VAP was defined using clinical, radiologic and quantitative microbiological data. VAP first episodes were prospectively identified using the continuous surveillance data. Exposure to different risk factors was taken into account until the diagnosis of ESBLE VAP or until ICU discharge, in patients with ESBLE VAP and VAP related to other bacteria, respectively. In all patients, routine screening for ESBLE (rectal swab) was performed at ICU admission and once a week. Patients with ESBLE VAP were compared with those with VAP related to other bacteria using univariate analysis. All significant factors were included in the multivariate logistic regression model.

RESULTS

Among the 410 patients with VAP, 43 (10.5%) had ESBLE VAP, 76 (19%) patients had polymicrobial VAP and 189 (46%) had VAP related to multidrug resistant bacteria. Multivariate analysis identified prior ESBLE colonization of the digestive tract as the only independent risk factor for ESBLE VAP (OR [95% CI] = 23 [10-55], p < 0.001). Whilst the positive predictive value of ESBLE digestive colonization was low (43.6%), its negative predictive value was excellent (97.3%) in predicting ESBLE VAP. Duration of mechanical ventilation (median [IQR], 28 [18,42] vs 23 [15,42] d, p = 0.4), length of ICU stay (31 [19,53] vs 29 [18,46] d, p = 0.6), and mortality rates (55.8% vs 50%, p = 0.48) were similar in ESBLE VAP, compared with VAP related to other bacteria.

CONCLUSION

Digestive tract colonization related to ESBLE is independently associated with ESBLE VAP. Its excellent negative predictive value suggests that patients without ESBLE colonization should not receive carbapenems as part of their initial empirical treatment to cover ESBLE.

World-Wide Variation in Incidence of Staphylococcus aureus Associated Ventilator-Associated Pneumonia: A Meta-Regression

Staphylococcus aureus (S. aureus) is a common Ventilator-Associated Pneumonia (VAP) isolate. The objective here is to define the extent and possible reasons for geographic variation in the incidences of S. aureus-associated VAP, MRSA-VAP and overall VAP. A meta-regression model of S. aureus-associated VAP incidence per 1000 Mechanical Ventilation Days (MVD) was undertaken using random effects methods among publications obtained from a search of the English language literature. This model incorporated group level factors such as admission to a trauma ICU, year of publication and use of bronchoscopic sampling towards VAP diagnosis. The search identified 133 publications from seven worldwide regions published over three decades. The summary S. aureus-associated VAP incidence was 4.5 (3.9–5.3) per 1000 MVD. The highest S. aureus-associated VAP incidence is amongst reports from the Mediterranean (mean; 95% confidence interval; 6.1; 4.1–8.5) versus that from Asian ICUs (2.1; 1.5–3.0). The incidence of S. aureus-associated VAP varies by up to three-fold (for the lowest versus highest incidence) among seven geographic regions worldwide, whereas the incidence of VAP varies by less than two-fold. Admission to a trauma unit is the most important group level correlate for S. aureus-associated VAP.

Unusually High Incidences of Staphylococcus aureus Infection within Studies of Ventilator Associated Pneumonia Prevention Using Topical Antibiotics: Benchmarking the Evidence Base

Selective digestive decontamination (SDD, topical antibiotic regimens applied to the respiratory tract) appears effective for preventing ventilator associated pneumonia (VAP) in intensive care unit (ICU) patients. However, potential contextual effects of SDD on Staphylococcus aureus infections in the ICU remain unclear. The S. aureus ventilator associated pneumonia (S. aureus VAP), VAP overall and S. aureus bacteremia incidences within component (control and intervention) groups within 27 SDD studies were benchmarked against 115 observational groups. Component groups from 66 studies of various interventions other than SDD provided additional points of reference. In 27 SDD study control groups, the mean S. aureus VAP incidence is 9.6% (95% CI; 6.9–13.2) versus a benchmark derived from 115 observational groups being 4.8% (95% CI; 4.2–5.6). In nine SDD study control groups the mean S. aureus bacteremia incidence is 3.8% (95% CI; 2.1–5.7) versus a benchmark derived from 10 observational groups being 2.1% (95% CI; 1.1–4.1). The incidences of S. aureus VAP and S. aureus bacteremia within the control groups of SDD studies are each higher than literature derived benchmarks. Paradoxically, within the SDD intervention groups, the incidences of both S. aureus VAP and VAP overall are more similar to the benchmarks.

Risk factors for ventilator-associated pneumonia among patients undergoing major oncological surgery for head and neck cancer

Patients undergoing major oncological surgery for head and neck cancer (SHNC) have a particularly high risk of nosocomial infections. We aimed to identify risk factors for ventilator-associated pneumonia (VAP) in patients undergoing SHNC. The study included 465 patients who underwent SHNC between June 2011 and June 2014. The rate of VAP, risk factors for VAP, and biological aspects of VAP were retrospectively evaluated. The incidence of VAP was 19.6% (n = 95) in patients who required more than 48 h of mechanical ventilation. Staphylococcus (37.7%), Enterobacteriaceae (32.1%), Pseudomonas (20.8%), and Haemophilus (16.9%) were the major bacterial species that caused VAP. The independent risk factors for VAP were advanced age, current smoking status, chronic obstructive pulmonary disease, and a higher simplified acute physiology score system II upon admission. Tracheostomy was an independent protective factor for VAP. The median length of stay in the ICU for patients who did or did not develop VAP was 8.0 and 6.5 days, respectively (P = 0.006). Mortality among patients who did or did not develop VAP was 16.8% and 8.4%, respectively (P < 0.001). The potential economic impact of VAP was high because of the significantly extended duration of ventilation. A predictive regression model was developed with a sensitivity of 95.3% and a specificity of 69.4%. VAP is common in patients who are undergoing SHNC and who require more than 48 h of mechanical ventilation. Therefore, innovative preventive measures should be developed and applied in this high-risk population.

Five-year mortality in patients treated for severe community-acquired pneumonia - a retrospective study

BACKGROUND

The mortality rate in patients with severe community-acquired pneumonia (SCAP) is high. We investigated the 5-year mortality rate and causes of death in a patient population treated for SCAP in our intensive care unit (ICU), and compared the mortality rate in patients with or without chronic obstructive pulmonary disease (COPD) as comorbidity.

METHODS

This retrospective study, which covers a period of 10 years, included patients aged > 18 years admitted to our ICU with SCAP as primary diagnosis and in need of mechanical ventilation for more than 24 h. Data were collected from the ICU internal database and the patients' medical records. The times of death were collected from the Norwegian National Registry, and the causes of death from the Norwegian Cause of Death Registry.

RESULTS

Hundred and seventy three patients were included in the study. The 5-year mortality rate for the total study population was 57.2%. There were no significant differences in the mortality rate between the group with COPD and the group without COPD (61.2% vs. 54.7%, P = 0.43). There was a wide range of comorbidities. The most common were COPD, myocardial infarction and diabetes mellitus. The two main causes of death after discharge were COPD (17 deaths) and cardiovascular diseases (seven deaths).

CONCLUSIONS

The 5-year mortality rate of the study population was high (57.2%). COPD did not seem to be a risk factor for mortality compared to non-COPD patients. The most common causes of death after discharge were COPD and cardiovascular diseases.

World-wide variation in incidence of Acinetobacter associated ventilator associated pneumonia: a meta-regression

Background

Acinetobacter species such as Acinetobacter baumanii are of increasing concern in association with ventilator associated pneumonia (VAP). In the ICU, Acinetobacter infections are known to be subject to seasonal variation but the extent of geographic variation is unclear. The objective here is to define the extent and possible reasons for geographic variation for Acinetobacter associated VAP whether or not these isolates are reported as Acinetobacter baumanii.

Methods

A meta-regression model of VAP associated Acinetobacter incidence within the published literature was undertaken using random effects methods. This model incorporated group level factors such as proportion of trauma admissions, year of publication and reporting practices for Acinetobacter infection.

Results

The search identified 117 studies from seven worldwide regions over 29 years. There is significant variation in Acinetobacter species associated VAP incidence among seven world-wide regions. The highest incidence is amongst reports from the Middle East (mean; 95 % confidence interval; 8.8; 6 · 2–12 · 7 per 1000 mechanical ventilation days) versus that from North American ICU’s (1 · 2; 0 · 8–2 · 1). There is a similar geographic related disparity in incidence among studies reporting specifically as Acinetobacter baumanii. The incidence in ICU’s with a majority of admission being for trauma is >2.5 times that of other ICU’s.

Conclusion

There is greater than fivefold variation in Acinetobacter associated VAP among reports from various geographic regions worldwide. This variation is not explainable by variations in rates of VAP overall, admissions for trauma, publication year or Acinetobacter reporting practices as group level variables.

Electronic supplementary material

The online version of this article (doi:10.1186/s12879-016-1921-4) contains supplementary material, which is available to authorized users.

Current Applications for the Use of Extracorporeal Carbon Dioxide Removal in Critically Ill Patients

Mechanical ventilation in patients with respiratory failure has been associated with secondary lung injury, termed ventilator-induced lung injury. Extracorporeal venovenous carbon dioxide removal (ECCO₂R) appears to be a feasible means to facilitate more protective mechanical ventilation or potentially avoid mechanical ventilation in select patient groups. With this expanding role of ECCO₂R, we aim to describe the technology and the main indications of ECCO₂R.

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.

A novel anti-PcrV antibody providing enhanced protection against Pseudomonas aeruginosa in multiple animal infection models

Pseudomonas aeruginosa is a major cause of hospital-acquired infections, particularly in mechanically ventilated patients, and it is the leading cause of death in cystic fibrosis patients. A key virulence factor associated with disease severity is the P. aeruginosa type III secretion system (T3SS), which injects bacterial toxins directly into the cytoplasm of host cells. The PcrV protein, located at the tip of the T3SS injectisome complex, is required for T3SS function and is a well-validated target in animal models of immunoprophylactic strategies targeting P. aeruginosa. In an effort to identify a highly potent and protective monoclonal antibody (MAb) that inhibits the T3SS, we generated and characterized a panel of novel anti-PcrV MAbs. Interestingly, some MAbs exhibiting potent inhibition of T3SS in vitro failed to provide protection in a mouse model of P. aeruginosa infection, suggesting that effective in vivo inhibition of T3SS with anti-PcrV MAbs is epitope dependent. V2L2MD, while not the most potent MAb as assessed by in vitro cytotoxicity inhibition assays, provided strong prophylactic protection in several murine infection models and a postinfection therapeutic model. V2L2MD mediated significantly (P < 0.0001) better in vivo protection than that provided by a comparator antibody, MAb166, a well-characterized anti-PcrV MAb and the progenitor of a clinical candidate, KB001-A. The results described here support further development of a V2L2MD-containing immunotherapeutic and may suggest even greater potential than was previously recognized for the prevention and treatment of P. aeruginosa infections in high-risk populations.

Impact of ventilator associated pneumonia on outcome in patients with chronic obstructive pulmonary disease exacerbation

Background and Objective:

There are sparse data regarding the impact of ventilator-associated pneumonia (VAP) on outcome among patients with chronic obstructive pulmonary disease (COPD) exacerbation.

Materials and Methods:

This retrospective study included patients with COPD exacerbation requiring endotracheal intubation for more than 48 h admitted in a single respiratory unit from January 2008 to December 2009. Records of these patients were checked for the occurrence of VAP.

Results:

One hundred and fifty-three patients required endotracheal intubation for COPD exacerbation during this period. The mean age of this cohort was 61.46 ± 11.3 years. The median duration of COPD was 6 years (range: 1-40). A total of 35 (22.8%) patients developed VAP (early: 9 and late: 26). The risk of mortality was comparable between two groups, that is, patients with and without VAP [odd's ratio (OR)−1.125; 95% confidence interval (CI), 0.622-2.035]. The duration of mechanical ventilation and hospital stay (median ± standard error, 95% CI) was 32 ± 10 (95% CI, 13-51) versus 10 ± 2 (95% CI, 6-14) days; P ≤ 0.001 and 53 ± 26 (95% CI, 3-103) versus 18 ± 7 (95% CI, 5-31) days; P = 0.031, respectively was higher among patients with VAP.

Conclusions:

Our study has shown that VAP leads to increased duration of mechanical ventilation and hospital stay; however, the mortality is not affected.

Assessment of severity of ICU-acquired pneumonia and association with etiology

OBJECTIVES

We evaluated the association between severity of illness and microbial etiology of ICU-acquired pneumonia to define if severity should be used to guide empiric antibiotic choices.

DESIGN

Prospective observational study.

SETTING

ICUs of a university hospital.

PATIENTS

Three hundredy forty-three consecutive patients with ICU-acquired pneumonia clustered, according to the presence of multidrug resistant pathogens.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Two hundred eight patients had ventilator-associated pneumonia and 135 had nonventilator ICU-acquired pneumonia. We determined etiology in 217 patients (63%). The most frequent pathogens were Pseudomonas aeruginosa, Enterobacteriaceae, and methicillin-sensitive and methicillin-resistant Staphylococcus aureus. Fifty-eight patients (17%) had a multidrug-resistant causative agent. Except for a longer ICU stay and a higher rate of microbial persistence at the end of the treatment in the multidrug-resistant group, no differences were found in clinical and inflammatory characteristics, severity criteria, and mortality or survival between patients with and without multidrug-resistant pathogens, even after adjusting for potential confounders. Patients with higher severity scores (Acute Physiology and Chronic Health Evaluation II and Sepsis-related Organ Failure Assessment) and septic shock at onset of pneumonia had significantly lower 28- and 90-day survival and higher systemic inflammatory response. The results were similar when only patients with microbial diagnosis were considered, as well as when stratified into ventilator-associated pneumonia and nonventilator ICU-acquired pneumonia.

CONCLUSIONS

In patients with ICU-acquired pneumonia, severity of illness seems not to affect etiology. Risk factors for multidrug resistant, but not severity of illness, should be taken into account in selecting empiric antimicrobial treatment.

Impact of chronic liver disease in intensive care unit acquired pneumonia: a prospective study

PURPOSE

To assess the impact of chronic liver disease (CLD) on ICU-acquired pneumonia.

METHODS

This was a prospective, observational study of the characteristics, microbiology, and outcomes of 343 consecutive patients with ICU-acquired pneumonia clustered according to the presence of CLD.

RESULTS

Sixty-seven (20%) patients had CLD (67% had liver cirrhosis, LC), MELD score 26 ± 9, 20% Child-Pugh class C). They presented higher severity scores than patients without CLD both on admission to the ICU (APACHE II, LC 19 ± 6 vs. other CLD 18 ± 6 vs. no CLD 16 ± 6; p < 0.001; SOFA, 10 ± 3 vs. 8 ± 4 vs. 7 ± 3; p < 0.001) and at onset of pneumonia (APACHE II, 19 ± 6 vs. 17 ± 6 vs. 16 ± 5; p = 0.001; SOFA, 11 ± 4 vs. 9 ± 4 vs. 7 ± 3; p < 0.001). Levels of CRP were lower in patients with LC than in the other two groups (day 1, 6.5 [2.5-11.5] vs. 13 [6-23] vs. 15.5 [8-24], p < 0.001, day 3, 6 [3-12] vs. 16 [9-21] vs. 11 [5-20], p = 0.001); all the other biomarkers were higher in LC and other CLD patients. LC patients had higher 28- and 90-day mortality (63 vs. 28%, p < 0.001; 72 vs. 38%, p < 0.001, respectively) than non-CLD patients. Presence of LC was independently associated with decreased 28- and 90-day survival (95% confidence interval [CI], 1.982-17.250; p = 0.001; 95% confidence interval [CI], 2.915-20.699, p = 0.001, respectively).

CONCLUSIONS

In critically ill patients with ICU-acquired pneumonia, CLD is associated with a more severe clinical presentation and poor clinical outcomes. Moreover, LC is independently associated with 28- and 90-day mortality. The results of this study are important for future trials focused on mortality.

Assessment of intraoperative microaspiration: does a modified cuff shape improve sealing?

BACKGROUND

Intra-operative aspiration of oropharyngeal secretions is associated with post-operative pneumonia. The use of endotracheal tubes (ETTs) with a modified cuff shape could be one preventive action. In this clinical, prospective, randomised controlled trial, we hypothesised that altering the cuff shape to a tapered shape could reduce the aspiration incidence. The primary outcome was aspiration of dye solution into the trachea.

METHODS

Patients scheduled for lumbar surgery were intubated with either an ETT with a barrel-shaped polyvinylchloride cuff (control group, n = 30) or tapered-shaped polyvinylchloride cuff (intervention group, n = 30). Subsequently, instillation with methylthioninium chloride was performed. At 10, 30, 60, 90, and 120 min after intubation, bronchoscopy was performed assessing the degree of dye descent along the cuff and digitally stored. Single blind review of the videoclips provided data on incidence of dye aspiration and depth of penetration along the cuff.

RESULTS

The traditional cuff showed descent of dye into the trachea in 20% of the patients. Although a tapered-shaped polyvinylchloride cuff leaked up to the second third of the cuff, no dye leakage into the trachea was observed. The use of a tapered-shaped cuff had a protective role against aspiration (T30: OR 3.0, CI 1.57-5.75; P = 0.001).

CONCLUSIONS

Short-term use of tapered-shaped polyvinylchloride cuffs in surgical patients results in more effective sealing of the tracheal lumen in comparison with a traditional barrel-shaped polyvinylchloride cuffs. Further evaluation is needed to determine whether a reduction in post-operative pneumonia can be demonstrated when these cuffs are used.

Removing extra CO2 in COPD patients

For patients experiencing acute respiratory failure due to a severe exacerbation of chronic obstructive pulmonary disease (COPD), noninvasive positive pressure ventilation has been shown to significantly reduce mortality and hospital length of stay compared to respiratory support with invasive mechanical ventilation. Despite continued improvements in the administration of noninvasive ventilation (NIV), refractory hypercapnia and hypercapnic acidosis continue to prevent its successful use in many patients. Recent advances in extracorporeal gas exchange technology have led to the development of systems designed to be safer and simpler by focusing on the clinical benefits of partial extracorporeal carbon dioxide removal (ECCO2R), as opposed to full cardiopulmonary support. While the use of ECCO2R has been studied in the treatment of acute respiratory distress syndrome (ARDS), its use for acute hypercapnic respiratory during COPD exacerbations has not been evaluated until recently. This review will focus on literature published over the last year on the use of ECCO2R for removing extra CO2 in patients experiencing an acute exacerbation of COPD.

Association between systemic corticosteroids and outcomes of intensive care unit-acquired pneumonia

OBJECTIVE

The use of corticosteroids is frequent in critically-ill patients. However, little information is available on their effects in patients with intensive care unit-acquired pneumonia. We assessed patients' characteristics, microbial etiology, inflammatory response, and outcomes of previous corticosteroid use in patients with intensive care unit-acquired pneumonia.

DESIGN

Prospective observational study.

SETTING

Intensive care units of a university teaching hospital.

PATIENTS

Three hundred sixteen patients with intensive care unit-acquired pneumonia. Patients were divided according to previous systemic steroid use at onset of pneumonia.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Survival at 28 days was analyzed using Cox regression, with adjustment for the propensity for receiving steroid therapy. One hundred twenty-five (40%) patients were receiving steroids at onset of pneumonia. Despite similar baseline clinical severity, steroid treatment was associated with decreased 28-day survival (adjusted hazard ratio for propensity score and mortality predictors 2.503; 95% confidence interval 1.176-5.330; p = .017) and decreased systemic inflammatory response. In post hoc analyses, steroid treatment had an impact on survival in patients with nonventilator intensive care unit-acquired pneumonia, those with lower baseline severity and organ dysfunction, and those without etiologic diagnosis or bacteremia. The cumulative dosage of corticosteroids had no significant effect on the risk of death, but bacterial burden upon diagnosis was higher in patients receiving steroid therapy.

CONCLUSIONS

In critically-ill patients, systemic corticosteroids should be used very cautiously because this treatment is strongly associated with increased risk of death in patients with intensive care unit-acquired pneumonia, particularly in the absence of established indications and in patients with lower baseline severity. Decreased inflammatory response may result in delayed clinical suspicion of intensive care unit-acquired pneumonia and higher bacterial count.

Impact of clinical severity index, infective pathogens, and initial empiric antibiotic use on hospital mortality in patients with ventilator-associated pneumonia

BACKGROUND

The prompt initial use of appropriate antibiotics should improve mortality rates in adults with ventilator-associated pneumonia (VAP). However, the incidence of multidrug-resistant (MDR) pathogen infections is on the rise, and the choice of the initial empiric antibiotic may be challenging. We investigated whether appropriate initial antibiotic therapy, infective pathogens, and the clinical severity index influence hospital mortality in patients with VAP and determined independent risk factors for the same.

METHODS

This study evaluated 163 adult patients (aged ≥ 18 years) at Chang Gung Memorial Hospital, Kaohsiung, Taiwan, from January 1, 2007, to January 31, 2008. Eligibility was evaluated based on criteria for VAP. Sequential Organ Failure Assessment (SOFA) scores, Acute Physiological Assessment and Chronic Health Evaluation II (APACHE II) scores, oxygenation index, underlying comorbidities, septic shock status, previous tracheostomy status, and factors related to pneumonia were collected for analysis.

RESULTS

Ninety-two patients survived from a total 163 patients with VAP during the course of their confinement in the intensive care unit. Multivariable logistic regression analysis identified that a pre-existing Charlson Comorbidity Index score (P = .011), initial oxygenation index (P = .025), SOFA score (P = .043), VAP caused by Acinetobacter baumanii (P = .030), and infection with MDR pathogens (P = .003) were independent risk factors for hospital mortality in patients with VAP.

CONCLUSION

High Charlson Comorbidity Index score, high initial oxygenation index, high SOFA score, and infection with Acinetobacter baumannii or MDR pathogens significantly affect hospital mortality in patients with VAP.

Ventilator-Associated Pneumonia: Depends on Your Definition

Reduction of hospital-acquired infections is a patient safety goal and regularly monitored by Performance Improvement committees. There is discordance between the ventilator-associated pneumonia (VAP) rate reported by the Infection Control Committee (ICC) and that observed by our Trauma Service. To investigate this difference, a retrospective evaluation of cases of VAP diagnosed on a single service was undertaken. A prospectively collected database was queried for VAP in intensive care unit patients between January 2010 and June 2011. This was compared with the list of mechanically ventilated patients provided by the ICC. Comparison for criteria used to diagnose pneumonia, ventilator day of the diagnosis, was recorded. The ICC identified two VAPs from 136 potential patients compared with the Trauma Service identifying 36 VAPs. A difference in diagnostic criteria between the ICC and the Trauma Service focused on use of the National Nosocomial Infection Survey (NNIS) algorithm versus quantitative microbiology from bronchoalveolar lavage specimens. Thirty-five of 36 Trauma Service VAPs were not identified as VAPs by the NNIS algorithm as a result of the chest radiographs. Application of differing definitions of VAP results in markedly different VAP rates. The difference has significant implications as infection rates are increasingly reported as a quality metric.

Ventilator-associated pneumonia: a comprehensive review

Ventilator-associated pneumonia (VAP) is the most frequent and severe infection acquired in the intensive care unit, leading to prolonged mechanical ventilation and excess mortality. This article reviews the different aspects of VAP, such as risk factors, causative agents, and approaches to diagnosis, treatment, and prevention. Several aspects of VAP are still considered controversial.

Diagnosis of ventilator-associated respiratory infections (VARI): microbiologic clues for tracheobronchitis (VAT) and pneumonia (VAP)

Intubated patients are at risk of bacterial colonization and ventilator-associated respiratory infection (VARI). VARI includes tracheobronchitis (VAT) or pneumonia (VAP). VAT and VAP caused by multidrug-resistant (MDR) pathogens are increasing in the United States and Europe. In patients with risk factors for MDR pathogens, empiric antibiotics are often initiated for 48 to 72 hours pending the availability of pathogen identification and antibiotic sensitivity data. Extensive data indicate that early, appropriate antibiotic therapy improves outcomes for patients with VAP. Recognizing and treating VARI may allow earlier appropriate therapy and improved patient outcomes.

Incidence and clinical implication of nosocomial infections associated with implantable biomaterials - catheters, ventilator-associated pneumonia, urinary tract infections

Health care associated infections, the fourth leading cause of disease in industrialised countries, are a major health issue. One part of this condition is based on the increasing insertion and implantation of prosthetic medical devices, since presence of a foreign body significantly reduces the number of bacteria required to produce infection. The most significant hospital-acquired infections, based on frequency and potential severity, are those related to procedures e.g. surgical site infections and medical devices, including urinary tract infection in catheterized patients, pneumonia in patients intubated on a ventilator and bacteraemia related to intravascular catheter use. At least half of all cases of nosocomial infections are associated with medical devices.Modern medical and surgical practices have increasingly utilized implantable medical devices of various kinds. Such devices may be utilized only short-time or intermittently, for months, years or permanently. They improve the therapeutic outcome, save human lives and greatly enhance the quality of life of these patients. However, plastic devices are easily colonized with bacteria and fungi, able to be colonized by microorganisms at a rate of 0.5 cm per hour. A thick biofilm is formed within 24 hours on the entire surface of these plastic devices once inoculated even with a small initial number of bacteria.The aim of the present work is to review the current literature on causes, frequency and preventive measures against infections associated with intravascular devices, catheter-related urinary tract infection, ventilator-associated infection, and infections of other implantable medical devices. Raising awareness for infection associated with implanted medical devices, teaching and training skills of staff, and establishment of surveillance systems monitoring device-related infection seem to be the principal strategies used to achieve reduction and prevention of such infections. The intelligent use of suitable antiseptics in combination with medical devices may further support reduction and prevention of such infections. In addition to reducing the adverse clinical outcomes related with these infections, such reduction may substantially decrease the economic burden caused by device-related infection for health care systems.