Impact of diagnostic criteria on the incidence of ventilator-associated pneumonia

[Epidemiology, diagnosis and treatment of adult patients with nosocomial pneumonia]

BACKGROUND

 Nosocomial pneumonia, encompassing hospital-acquired (HAP) and ventilator-associated pneumonia (VAP), remains a major cause of morbidity and mortality in hospitalized adults. In response to evolving pathogen profiles and emerging resistance patterns, this updated S3 guideline (AWMF Register No. 020-013) provides an evidence-based framework to enhance the diagnosis, risk stratification, and treatment of nosocomial pneumonia.

METHODS

 The guideline update was developed by a multidisciplinary panel representing key German professional societies. A systematic literature review was conducted with subsequent critical appraisal using the GRADE methodology. Structured consensus conferences and external reviews ensured that the recommendations were clinically relevant, methodologically sound, and aligned with current antimicrobial stewardship principles.

RESULTS

 For the management of nosocomial pneumonia patients should be divided in those with and without risk factors for multidrug-resistant pathogens and/or Pseudomonas aeruginosa. Bacterial multiplex-polymerase chain reaction (PCR) should not be used routinely. Bronchoscopic diagnosis is not considered superior to non-bronchoscopic sampling in terms of main outcomes. Combination antibiotic therapy is now reserved for patients in septic shock and high risk for multidrug-resistant pathogens, while select patients may be managed with monotherapy (e. g., meropenem). In clinically stabilized patients, antibiotic therapy should be de-escalated and focused, as well as duration shortened to 7-8 days. In critically ill patients, prolonged application of suitable beta-lactam antibiotics should be preferred. Patients on the intensive care unit (ICU) are at risk for invasive pulmonary aspergillosis (IPA). Diagnostics for Aspergillus should be performed with an antigen test from bronchial lavage fluid.

CONCLUSION

 This updated S3 guideline offers a comprehensive, multidisciplinary approach to the management of nosocomial pneumonia in adults. By integrating novel diagnostic modalities and refined therapeutic strategies, it aims to standardize care, improve patient outcomes, and enhance antimicrobial stewardship to curb the emergence of resistant pathogens.

Diagnostic Stewardship of Endotracheal Aspirate Cultures in Hospitalized Children With Artificial Airways: Expert Consensus Statements From the BrighT STAR (Testing STewardship for Antibiotic Reduction) Respiratory Collaborative

OBJECTIVE

To develop consensus statements that clinicians can apply to standardize and optimize endotracheal aspirate culture (EAC) practices in hospitalized children with artificial airways who are being evaluated for a bacterial lower respiratory tract infection (LRTI).

DESIGN

A modified Delphi consensus process with expert panelists. Panelists conducted a "pre-survey" to itemize respiratory signs of bacterial LRTI. Round 1 included a literature summary and electronic survey of 50 potential statements sent to all panelists. We surveyed panelist opinions using a 5-point Likert scale. We grouped the responses "agree" and "strongly agree" as agreement. Consensus was defined as statements reaching greater than 75% agreement. Round 2 was moderated by an independent expert in consensus methodology. Panelists convened in person in November 2023, discussed any statements not reaching consensus or statements with disagreement, were resurveyed, and finalized statements in real time.

SETTING

Electronic surveys and in-person meetings in Baltimore, MD.

SUBJECTS

The BrighT STAR (Testing STewardship for Antibiotic Reduction) collaborative along with U.S.-based pediatric experts in critical care, cardiac critical care, infectious diseases, hospital medicine, otolaryngology, pulmonology, and clinical microbiology.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Thirty-eight of 40 invited panelists completed round 1. Of 50 initial statements, 28 reached greater than 90% agreement, 16 had 75-89% agreement, and 6 had less than 75% agreement. Twenty-eight statements were finalized. Round 2 involved 37 panelists: 23 statements were discussed, of which 17 reached an agreement and 6 did not reach consensus. We concluded with 30 statements and 15 sub-statements, 37 of which had greater than 90% agreement. Final statements informed a clinical decision support algorithm.

CONCLUSIONS

The BrighT STAR collaborative group achieved consensus for 45 clinical practice statements that can standardize EAC practices, including indications to consider for testing, reasons to defer, optimal specimen collection, and result interpretation. These statements offer a starting point for clinical decision support tools and diagnostic stewardship programs for EAC practices in patients with artificial airways.

Analysis of Bacterial Metabolites in Breath Gas of Critically Ill Patients for Diagnosis of Ventilator-Associated Pneumonia-A Proof of Concept Study

Bacterial infection of the lower respiratory tract frequently occurs in mechanically ventilated patients and may develop into life-threatening conditions. Yet, existing diagnostic methods have moderate sensitivity and specificity, which results in the overuse of broad-spectrum antibiotics administered prophylactically. This study aims to evaluate the suitability of volatile bacterial metabolites for the breath-based test, which is used for diagnosing Ventilator-Associated Pneumonia (VAP). The in vitro experiments with pathogenic bacteria most prevalent in VAP etiology (i.e., Acinetobacter baumannii, Escherichia coli, Klebsiella pneumoniae, and Pseudomonas aeruginosa) were performed to identify bacteria-derived metabolites using a specially designed cultivation system enabling headspace sampling for GC-MS analysis. Thirty-nine compounds were found to be significantly metabolized by tested species and, therefore, selected for monitoring in the exhaled breath of critically ill, mechanically ventilated (MV) patients. The emission of volatiles from medical respiratory devices was investigated to estimate the risk of spoiling breath results with exogenous pollutants. Bacterial metabolites were then evaluated to differentiate VAP patients from non-infected MV controls using Receiver Operating Characteristic (ROC) analysis, with AUC, sensitivity, and specificity calculated. Nine bacterial metabolites that passed verification through a non-parametric ANOVA test for significance and LASSO penalization were identified as key discriminators between VAP and non-VAP patients. The diagnostic model achieved an AUC of 0.893, with sensitivity and specificity values of 87% and 82.4%, respectively, being competitive with traditional methods. Further validation could solidify its clinical utility in critical care settings.

Duration of Antimicrobial Treatment in Adult Patients with Pneumonia: A Narrative Review

Pneumonia remains a major global health concern, causing significant morbidity and mortality among adults. This narrative review assesses the optimal duration of antimicrobial treatment in adults with community-acquired pneumonia (CAP), hospital-acquired pneumonia (HAP), and ventilator-associated pneumonia (VAP). Current evidence about the impact of treatment duration on clinical outcomes demonstrates that shorter antibiotic courses are non-inferior, regarding safety and efficacy, compared to longer courses, particularly in patients with mild to moderate CAP, which is in line with the recommendations of international guidelines. Data are limited regarding the optimal antimicrobial duration in HAP patients, and it should be individually tailored to each patient, taking into account the causative pathogen and the clinical response. Shorter courses are found to be as effective as longer courses in the management of VAP, except for pneumonia caused by non-fermenting Gram-negative bacteria; however, duration should be balanced between the possibility of higher recurrence rates and the documented benefits with shorter courses. Additionally, the validation of reliable biomarkers or clinical predictors that identify patients who would benefit from shorter therapy is crucial. Insights from this review may lead to future research on personalized antimicrobial therapies in pneumonia, in order to improve patient outcomes.

The preventive effect of inhaled antibiotic against ventilator-associated pneumonia: A systematic review and meta-analysis

BACKGROUND

Ventilator-associated pneumonia (VAP) constitutes a considerable challenge for patients in intensive care units (ICUs) and necessitates the development of effective preventive strategies. This study aimed to evaluate the clinical efficacy of inhaled antibiotics for preventing VAP.

METHODS

PubMed, Embase, and ClinicalTrials.gov were searched until 21 January 2024. Randomized controlled trials investigating the clinical efficacy of inhaled antibiotics for VAP prevention were included.

RESULTS

Seven randomized controlled trials, involving 1465 patients, of whom 734 were classified as the study group receiving inhaled antibiotics and 731 as the control group receiving placebo were included in this meta-analysis. Overall, the occurrence of VAP was significantly lower in the study group than in the control group (risk ratio, 0.69; 95% confidence interval [CI], 0.51-0.92). However, there were no significant differences in mortality (risk ratio, 0.90; 95% CI, 0.74-1.09), length of stay in ICU (mean difference [MD], 0.10 d; 95% CI, -0.91 to 1.1), and hospital (MD, 0.30 d; 95% CI, -1.82 to 2.43), and mechanical ventilation duration (MD, 0.45 d; 95% CI, -0.45 to 1.35) between groups.

CONCLUSIONS

Inhaled antibiotics hold promise for mitigating the risk of VAP among critically ill patients. However, their impact on mortality, length of stay in ICU and hospital, and mechanical ventilation duration was not statistically significant.

Surveillance of ventilator associated pneumonia in a network of indian hospitals using modified definitions: a pilot study

Background

Ventilator-associated pneumonia (VAP) is a major cause of morbidity and mortality in patients receiving mechanical ventilation in India. Surveillance of VAP is essential to implement data-based preventive measures. Implementation of ventilator-associated events (VAE) criteria for surveillance has major constraints for low resource settings, which can lead to significant underreporting. Surveillance of VAP using common protocols in a large network of hospitals would give meaningful estimates of the burden of VAP in low resource settings. This study leverages a previously established healthcare-associated infections (HAI) surveillance network to develop and test a modified VAP definition adjusted for Indian settings.

Methods

In this observational pilot study, thirteen hospitals from the existing HAI surveillance network were selected for developing and testing a modified VAP definition between February 2021 and April 2023. The criteria used for diagnosing VAP were adapted from the CDC's Pediatric VAP definition and modified to cater to the needs of Indian hospitals. Designated nurses recorded each VAP event in a case report form (CRF) and also collected denominator data. The data was entered into an indigenously developed database for validation and analysis. At the time of data analysis, a questionnaire was sent to sites to get feedback on the performance of the modified VAP definitions.

Findings

Out of 133,445 patient days and 40,533 ventilator days, 261 VAP events were recorded, with an overall VAP rate of 6.4 per 1000 ventilator days and a device utilization ratio (DUR) of 0.3. A total of 344 organisms were reported from the VAP events. Of these, Acinetobacter spp (29.6%, 102) was the most frequent, followed by Klebsiella spp (26.7%, 92). Isolates of Acinetobacter spp (98%) and Enterobacterales (85.5%) showed very high resistance against Carbapenem. Colistin resistance was observed in 6% of Enterobacterales and 3.2% of Acinetobacter spp.

Interpretation

Data from this pilot study needs to validated in the larger Indian HAI surveillance network so that it can help in wider implementation of this protocol in order to assess its applicability p VAP across India.

Funding

This work was supported by a grant received from the Indian Council of Medical Research (code I-1203).

Ventilator-associated pneumonia: pathobiological heterogeneity and diagnostic challenges

Ventilator-associated pneumonia (VAP) affects up to 20% of critically ill patients and induces significant antibiotic prescription pressure, accounting for half of all antibiotic use in the ICU. VAP significantly increases hospital length of stay and healthcare costs yet is also associated with long-term morbidity and mortality. The diagnosis of VAP continues to present challenges and pitfalls for the currently available clinical, radiological and microbiological diagnostic armamentarium. Biomarkers and artificial intelligence offer an innovative potential direction for ongoing future research. In this Review, we summarise the pathobiological heterogeneity and diagnostic challenges associated with VAP.

The Clinical Pulmonary Infection Score Combined with Procalcitonin and Lung Ultrasound (CPIS-PLUS), a Good Tool for Ventilator Associated Pneumonia Early Diagnosis in Pediatrics

Ventilator-associated pneumonia (VAP) is common in Pediatric Intensive Care Units. Although early detection is crucial, current diagnostic methods are not definitive. This study aimed to identify lung ultrasound (LUS) findings and procalcitonin (PCT) values in pediatric patients with VAP to create a new early diagnosis score combined with the Clinical Pulmonary Infection Score (CPIS), the CPIS-PLUS score. Prospective longitudinal and interventional study. Pediatric patients with suspected VAP were included and classified into VAP or non-VAP groups, based on Centers of Disease Control (CDC) criteria for the final diagnosis. A chest-X-ray (CXR), LUS, and blood test were performed within the first 12 h of admission. CPIS score was calculated. A total of 108 patients with VAP suspicion were included, and VAP was finally diagnosed in 51 (47%) patients. CPIS-PLUS showed high accuracy in VAP diagnosis with a sensitivity (Sn) of 80% (95% CI 65-89%) and specificity (Sp) of 73% (95% CI 54-86%). The area under the curve (AUC) resulted in 0.86 for CPIS-PLUS vs. 0.61 for CPIS. In conclusion, this pilot study showed that CPIS-PLUS could be a potential and reliable tool for VAP early diagnosis in pediatric patients. Internal and external validations are needed to confirm the potential value of this score to facilitate VAP diagnosis in pediatric patients.

Assessing Respiratory Tract Infections' Prevalence and Microbial Profiles in Mechanically Ventilated Patients: Insights From Broncho Alveolar Lavage Examination

Introduction Chest infections represent a significant challenge in mechanically ventilated patients, often leading to adverse outcomes despite advancements in critical care. This prospective study was conducted in the intensive care unit of tertiary referral care, with objectives to assess chest infection prevalence, microbial profiles, and outcomes in mechanically ventilated patients through broncho-alveolar lavage (BAL) examination. Methodology This prospective study involved 38 patients aged 15 to 65 years who were receiving mechanical ventilation and underwent BAL. The procedure of BAL was followed as per the guidelines and recommendations outlined by the American Thoracic Society for Bronchoscopic Lavage. Microbial analysis involves the use of microscopic examination and quantitative culture methods. Different staining techniques were utilized to identify bacteria, fungi, and mycobacteria. Complications and adverse events were monitored and recorded. Results Out of the 38 patients who underwent BAL, the majority, 30 (78.94%), were found to have chest infections, with gram-negative bacteria, including Escherichia coli, Klebsiella pneumoniae, and Acinetobacter baumannii, being the causative agents. The antibiotic sensitivity profiles indicated that the organisms were susceptible to carbapenems and broad-spectrum β-lactam/β-lactamase inhibitor combinations while showing resistance to fluoroquinolones. Despite adequate treatment, mortality remained significant in 12 (31.57%) patients. Conclusion Study findings underscore the importance of proactive surveillance, early diagnosis, and targeted management strategies to mitigate the burden of respiratory infections in critical care settings.

Graphene as a Sensor for Lung Cancer: Insights into Adsorption of VOCs Using vdW DFT

The adsorption mechanism of individual volatile organic compounds (VOCs) on the surface of graphene is investigated using nonempirical van der Waals (vdW) density functional theory. The VOCs chosen as adsorbates are ethanol, benzene, and toluene, which are found in the exhaled breath of lung cancer patients. The most energetically favorable configurations of the adsorbed systems, adsorption energy profiles, charge transfer, and work function are calculated. The fundamental insight into the interactions between the considered VOC molecules and graphene through molecular doping, i.e., charge transfer, is estimated. It is found that the adsorption energy is highly sensitive to the vdW functionals. Adsorption energies calculated by revPBE-vdW are in good agreement with the available experimental data, and the revPBE-vdW functional can cover well the physical phenomena behind the adsorption of these VOCs on graphene. Bader charge analysis shows that 0.064, 0.042, and 0.061e of charge were transferred from the graphene surface to ethanol, benzene, and toluene, respectively. All of the considered VOCs act as electron acceptors from graphene. By analyzing the electronic structure of the adsorption systems, we found that the energy level of the highest occupied molecular orbitals of these considered VOCs is shifted backward toward the Fermi level. The interaction of the VOCs with the π and π* states of the C atoms in graphene breaks the symmetry of graphene, leading to the opening of a band gap at the Fermi level. The adsorption of these considered VOCs onto the pristine graphene produces a band gap of 5-12 meV.

Inhaled Amikacin to Prevent Ventilator-Associated Pneumonia

BACKGROUND

Whether preventive inhaled antibiotics may reduce the incidence of ventilator-associated pneumonia is unclear.

METHODS

In this investigator-initiated, multicenter, double-blind, randomized, controlled, superiority trial, we assigned critically ill adults who had been undergoing invasive mechanical ventilation for at least 72 hours to receive inhaled amikacin at a dose of 20 mg per kilogram of ideal body weight once daily or to receive placebo for 3 days. The primary outcome was a first episode of ventilator-associated pneumonia during 28 days of follow-up. Safety was assessed.

RESULTS

A total of 850 patients underwent randomization, and 847 were included in the analyses (417 assigned to the amikacin group and 430 to the placebo group). All three daily nebulizations were received by 337 patients (81%) in the amikacin group and 355 patients (83%) in the placebo group. At 28 days, ventilator-associated pneumonia had developed in 62 patients (15%) in the amikacin group and in 95 patients (22%) in the placebo group (difference in restricted mean survival time to ventilator-associated pneumonia, 1.5 days; 95% confidence interval [CI], 0.6 to 2.5; P = 0.004). An infection-related ventilator-associated complication occurred in 74 patients (18%) in the amikacin group and in 111 patients (26%) in the placebo group (hazard ratio, 0.66; 95% CI, 0.50 to 0.89). Trial-related serious adverse effects were seen in 7 patients (1.7%) in the amikacin group and in 4 patients (0.9%) in the placebo group.

CONCLUSIONS

Among patients who had undergone mechanical ventilation for at least 3 days, a subsequent 3-day course of inhaled amikacin reduced the burden of ventilator-associated pneumonia during 28 days of follow-up. (Funded by the French Ministry of Health; AMIKINHAL ClinicalTrials.gov number, NCT03149640; EUDRA Clinical Trials number, 2016-001054-17.).

Incidence, microbiological and immunological characteristics of ventilator-associated pneumonia assessed by bronchoalveolar lavage and endotracheal aspirate in a prospective cohort of COVID-19 patients: CoV-AP study

BACKGROUND

No univocal recommendation exists for microbiological diagnosis of ventilator-associated pneumonia (VAP). Sampling of either proximal or distal respiratory tract likely impacts on the broad range of VAP incidence between cohorts. Immune biomarkers to rule-in/rule-out VAP diagnosis, although promising, have not yet been validated. COVID-19-induced ARDS made VAP recognition even more challenging, often leading to overdiagnosis and overtreatment. We evaluated the impact of different respiratory samples and laboratory techniques on VAP incidence and microbiological findings in COVID-19 patients.

METHODS

Prospective single-centre cohort study conducted among COVID-19 mechanically ventilated patients in Policlinico Hospital (Milan, Italy) from January 2021 to May 2022. Microbiological confirmation of suspected VAP (sVAP) was based on concomitant endotracheal aspirates (ETA) and bronchoalveolar lavage (BAL). Conventional and fast microbiology (FILMARRAY® Pneumonia Panel plus, BALFAPPP) as well as immunological markers (immune cells and inflammatory cytokines) was analysed.

RESULTS

Seventy-nine patients were included. Exposure to antibiotics and steroid therapy before ICU admission occurred in 51/79 (64.6%) and 60/79 (65.9%) patients, respectively. Median duration of MV at VAP suspicion was 6 (5-9) days. Incidence rate of microbiologically confirmed VAP was 33.1 (95% CI 22.1-44.0) and 20.1 (95% CI 12.5-27.7) according to ETA and BAL, respectively. Concordance between ETA and BAL was observed in 35/49 (71.4%) cases, concordance between BALFAPPP and BAL in 39/49 (79.6%) cases. With BAL as reference standard, ETA showed 88.9% (95% CI 70.8-97.7) sensitivity and 50.0% (95% CI 28.2-71.8) specificity (Cohen's Kappa 0.40, 95% CI 0.16-0.65). BALFAPPP showed 95.0% (95% CI 75.1-99.9) sensitivity and 69% (95% CI 49.2-84.7) specificity (Cohen's Kappa 0.60, 95% CI 0.39-0.81). BAL IL-1β differed significantly between VAP (135 (IQR 11-450) pg/ml) and no-VAP (10 (IQR 2.9-105) pg/ml) patients (P = 0.03).

CONCLUSIONS

In COVID-19 ICU patients, differences in microbial sampling at VAP suspicion could lead to high variability in VAP incidence and microbiological findings. Concordance between ETA and BAL was mainly limited by over 20% of ETA positive and BAL negative samples, while BALFAPPP showed high sensitivity but limited specificity when evaluating in-panel targets only. These factors should be considered when comparing results of cohorts with different sampling. BAL IL-1β showed potential in discriminating microbiologically confirmed VAP.

CLINICAL TRIAL REGISTRATION

NCT04766983, registered on February 23, 2021.

Definitions, rates and associated mortality of ICU-acquired pneumonia: A multicenter cohort study

INTRODUCTION

We aimed to analyze intensive care unit (ICU)-acquired pneumonia according to 7 definitions, estimating associated hospital mortality.

METHODS

This cohort study was nested within an international randomized trial, evaluating the effect of probiotics on ICU-acquired pneumonia in 2650 mechanically ventilated adults. Each clinically suspected pneumonia was adjudicated by two physicians blinded to allocation and center. The primary outcome was ventilator-associated pneumonia (VAP) informed by ventilation for ≥2 days, new, progressive or persistent infiltrate plus 2 of: temperature > 38 °C or < 36 °C; leukopenia (<3 × 10(Fernando et al., 2020⁶⁾/L) or leukocytosis (>10 × 10(Fernando et al., 2020⁶⁾/L); and purulent sputum. We also used 6 other definitions estimating the risk of hospital mortality.

RESULTS

The frequency of ICU-acquired pneumonia varied by definition: the trial primary outcome VAP (21.6%), Clinical Pulmonary Infection Score (CPIS) (24.9%), American College Chest Physicians (ACCP) (25.0%), International Sepsis Forum (ISF) (24.4%), Reducing Oxidative Stress Study (REDOXS) (17.6%), Centers for Disease Control (CDC) (7.8%), and invasively microbiologically confirmed (1.9%). The trial primary outcome VAP (HR 1.31 [1.08, 1.60]), ISF (HR 1.32 [1.09,1.60]), CPIS (HR 1.30 [1.08,1.58]) and ACCP definitions (HR 1.22 [1.00,1.47]) were associated with hospital mortality.

CONCLUSIONS

Rates of ICU-acquired pneumonia vary by definition and are associated with differential increased risk of death.

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.

Impact of early enteral nutrition on ventilator associated pneumonia in intubated severe trauma patients: A propensity score-matched study

Background

Early enteral nutrition (EN) is recommended for critically ill patients. However, the impact of early EN on intubated severe trauma patients remains unclear.

Methods

Severely traumatized adult patients who received invasive mechanical ventilation (MV) for more than 48 h during intensive care unit (ICU) stay at our institution between 2017 and 2022 were retrospectively included. Early EN was defined as EN initiation ≤48 h from ICU admission and late EN >48 h. Propensity score matching (PSM) analysis was used to compare outcomes between the groups. The primary endpoint was the incidence of ventilator-associated pneumonia (VAP). Multivariable logistic regression analysis was performed to identify independent predictors of delayed EN.

Results

For final analysis, 337 intubated severe trauma patients were available, including 204 (60.5%) in the early EN group and 133 (39.5%) in the late EN group. After PSM, early EN patients had a lower incidence of VAP (12.9 vs. 25.8%, p = 0.026) and a shorter length of hospital stay (21 vs. 24 days, p = 0.015) compared to late EN patients. There was no demonstrable difference in mortality between the two groups. Abdominal trauma, massive blood transfusion, and serum albumin were identified as independent risk factors for delayed EN.

Conclusion

Early EN decreased the VAP rate and reduced the length of hospital stay in invasively ventilated patients with severe trauma. Abdominal injury, massive blood transfusion and low albumin were associated with delayed EN.

Ventilator-Associated Pneumonia, Multidrug-Resistant Bacteremia and Infection Control Interventions in an Intensive Care Unit: Analysis of Six-Year Time-Series Data

Ventilator-associated pneumonia (VAP) occurs more than 48h after mechanical ventilation and is associated with a high mortality rate. The current hospital-based study aims to investigate the association between VAP rate, incidence of bacteremia from multidrug-resistant (MDR) pathogens, and infection control interventions in a single case mix ICU from 2013 to 2018. Methods: The following monthly indices were analyzed: (1) VAP rate; (2) use of hand hygiene disinfectants; (3) isolation rate of patients with MDR bacteria; and (4) incidence of bacteremia/1000 patient-days (total cases, total carbapenem-resistant cases, and carbapenem-resistant Acinetobacter baumannii, Pseudomonas aeruginosa, and Klebsiella pneumoniae cases separately). Results: Time trends of infection control interventions showed increased rates in isolation of patients with MDR pathogens (p <0.001) and consumption of hand disinfectant solutions (p =0.001). The last four years of the study an annual decrease of VAP rate by 35.12% (95% CI: −53.52 to −9.41; p =0.01) was recorded, which significantly correlated not only with reduced trauma and cardiothoracic surgery patients (IRR:2.49; 95% CI: 2.09−2.96; p <0.001), but also with increased isolation rate of patients with MDR pathogens (IRR: 0.52; 95% CI: 0.27−0.99; p = 0.048), and hand disinfectants use (IRR: 0.40; 95% CI: 0.18−0.89; p =0.024). Conclusions: Infection control interventions significantly contributed to the decrease of VAP rate. Constant infection control stewardship has a stable time-effect and guides evidence-based decisions.

Strategies to prevent ventilator-associated pneumonia, ventilator-associated events, and nonventilator hospital-acquired pneumonia in acute-care hospitals: 2022 Update

The purpose of this document is to highlight practical recommendations to assist acute care hospitals to prioritize and implement strategies to prevent ventilator-associated pneumonia (VAP), ventilator-associated events (VAE), and non-ventilator hospital-acquired pneumonia (NV-HAP) in adults, children, and neonates. This document updates the Strategies to Prevent Ventilator-Associated Pneumonia in Acute Care Hospitals published in 2014. This expert guidance document is sponsored by the Society for Healthcare Epidemiology (SHEA), and is the product of a collaborative effort led by SHEA, the Infectious Diseases Society of America, the American Hospital Association, the Association for Professionals in Infection Control and Epidemiology, and The Joint Commission, with major contributions from representatives of a number of organizations and societies with content expertise.

Risk factors and outcomes associated with ventilator associated pneumonia amongst intubated trauma patients admitted to the general intensive care unit of a major trauma centre

Background

Despite the use of care bundles, ventilator associated pneumonia (VAP) remains a frequently occurring health care-associated infection, increasing costs, length of stay (LOS) and mortality. The incidence is higher amongst trauma patients, although due to variable definitions and study populations risk factors for developing VAP are disputed, with few reports from the UK.

Methods

This 6-year review of intubated trauma patients admitted to the general Intensive Care Unit (ICU) of a UK major trauma centre, collected data on suspected risk factors for VAP, as well as demographic information, outcomes and microbiology. Ninety-nine patients who developed VAP within the first 7 days of admission were compared with 191 patient who did not, with multivariable logistic regression used to control for confounding variables.

Results

Univariable analysis suggested that injury severity score (ISS) (34 v 29), head injury (66.7% v 50.8%), polytrauma (79.8% v 68.1%) and ventilator days (10 v 5) were associated with increased risk of VAP, but after adjustment only ventilator days remained significant (OR 1.04, 95% CI 1.01–1.06). Antibiotics within 24 h of admission were associated with reduced odds of developing VAP, whether this was for pulmonary prophylaxis (OR 0.43, 95% CI 0.22–0.83, p = 0.013) or non-pulmonary reasons (OR 0.27, 95% CI 0.15–0.51, p < 0.001).

Conclusions

Only increasing ventilator days was associated with increased odds of developing VAP. The use of early antimicrobials was associated strongly with a reduction in the odds of developing VAP; this could be explained by unmeasured confounding or a prophylactic effect against aspiration.

Probiotics in Critically Ill Patients: An Umbrella Review

Objectives

Data sources

Study selection

Data extraction

Data synthesis

Conclusion

How to cite this article

Poor Sensorium at the Time of Intubation Predicts Polymicrobial Ventilator Associated Pneumonia

Background

Ventilator-associated pneumonia (VAP) is the most common nosocomial infection in the intensive care unit and is associated with a high mortality rate.

Aim

The study was conducted to estimate the frequency, outcomes, and predictors of polymicrobial VAP.

Methods

A prospective observational study was conducted in mechanically ventilated adult patients in the medical intensive care unit in a tertiary care hospital in India from July 2016 to July 2018 with a 30-day follow-up period. The patients were grouped into monomicrobial and polymicrobial VAP. We compared the 30-day outcome parameters such as discharge from hospital, in-hospital stay, death, and complications such as catheter associated urinary tract infection (CAUTI), central line associated blood stream infection (CRBSI), bacteremia and collapse of lung. The predictors of polymicrobial VAP were identified by multiple logistic regression.

Results

Out of 301 patients clinically diagnosed with VAP, 151 patients were excluded, and the remaining 150 developed 186 episodes of VAP during the study period. The incidence of polymicrobial VAP was 62.9%. Out of 150 patients, 51 patients had monomicrobial VAP, and 99 had polymicrobial VAP. On univariate analysis, diabetes mellitus and poor sensorium (Glasgow Coma Scale [GCS] score <8) during endotracheal intubation; 30-day outcome, mean days of mechanical ventilation after VAP diagnosis and days in ICU; and CAUTI were significantly associated with polymicrobial VAP. On multivariable logistic regression, poor sensorium (GCS score <8) at the time of endotracheal intubation was an independent predictor of polymicrobial VAP.

Conclusion

The incidence of polymicrobial VAP is high in the medical ICU and is associated with increased duration of mechanical ventilation, hospital stay, and incidence of CAUTI. Poor GCS score was the single independent predictor of polymicrobial VAP.

Automatic Continuous Control of Cuff Pressure and Subglottic Secretion Suction Used Together to Prevent Pneumonia in Ventilated Patients-A Retrospective and Prospective Cohort Study

The ventilator bundle consists of multiple methods to reduce ventilator-associated pneumonia (VAP) rates in Intensive Care Units (ICU). The aim of the study was to evaluate how the continuous automatic pressure control in tapered cuffs of endotracheal/tracheostomy tubes applied along with continuous automatic subglottic secretion suction affect the incidence of VAP. In the prospective cohort (n = 198), the standard VAP bundle was modified by continuous automatic pressure control in taper-shaped cuff of endotracheal/tracheostomy tubes and subglottic secretion suction. VAP incidence, time to VAP onset, invasive mechanical ventilation days/free days, length of ICU stay, ICU mortality, and multidrug-resistant bacteria were assessed and compared to the retrospective cohort (n = 173) with the standard bundle (intermittent cuff pressure of standard cuff, lack of subglottic secretion suction). A smaller incidence of VAP (9.6% vs. 19.1%) and early onset VAP (1.5% vs. 8.1%) was found in the prospective compared to the retrospective cohort (p < 0.01). Patients in the prospective cohort were less likely to develop VAP (RR = 0.50; 95% CI: 0.29 to 0.85) and early-onset VAP (RR = 0.19; 95% CI: 0.05 to 0.64) and had longer time to onset VAP (median 9 vs. 5 days; p = 0.03). There was no significant difference (p > 0.05) between both cohorts in terms of invasive mechanical ventilation days/free days, length of ICU stay, ICU mortality and multidrug-resistant bacteria. Modification of the bundle for prevention of VAP can reduce early-onset VAP and total incidence of VAP and delay the time of VAP occurrence.

Incidence, Outcomes and Sex-Related Disparities in Pneumonia: A Matched-Pair Analysis with Data from Spanish Hospitals (2016-2019)

(1) Background: the purpose of this study is to analyze the incidence and in-hospital mortality (IHM) of community-acquired pneumonia (CAP) needing hospital admission and hospital-acquired pneumonia (HAP) in Spain (2016–2019). (2) Methods: using the Spanish Register of Specialized Care-Basic Minimum Database, we estimated the incidence of CAP and HAP. We matched each woman with a man with an identical age, according to comorbidities. (3) Results: we analyzed 518,838 cases of CAP and 38,705 cases of HAP, and 5192 ventilator-associated HAPs (13.4%). The incidence of CAP increased over time in both men (from 384.5 to 449.8 cases/105 population) and women (from 244.9 to 301.2 cases/105 population). Men showed a 47% higher adjusted incidence of CAP than women. The incidence of HAP increased over time in both men (from 302.3 to 342.2 cases/105 population) and women (from 139.2 to 167.6 cases/105 population). Men showed a 98% higher adjusted incidence of HAP than women. IHM was higher in men admitted for CAP than in women (12.9% vs. 12.2%; p < 0.001), but not in men who developed HAP (28.9% vs. 28.0%; p = 0.107). Men admitted for CAP (OR: 1.13; 95% CI: 1.10–1.15) and men who developed HAP (OR: 1.05; 95% CI: 1.01–1.10) had higher IHM than women. (4) Conclusions: men had higher incidence rates of CAP and HAP than women. Men admitted for CAP and men who developed HAP had higher IHM than women.

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.

Continuous Endotracheal Tube Cuff Pressure Control Decreases Incidence of Ventilator-Associated Pneumonia in Patients with Traumatic Brain Injury

BACKGROUND

Ventilator-associated pneumonia (VAP) is a common cause of morbidity and mortality in intensive care unit (ICU), and among the several preventative strategies described to reduce the incidence of VAP, the most important is the endotracheal tube cuff (ETC) pressure. The present study was conducted on 60 patients who required mechanical ventilation (MV) in the ICU with traumatic brain injury (TBI).

METHODS

The patients were randomized into two groups of 30, in which ETC pressure was regulated using a smart cuff manager (SCM) (Group II), or manual measurement approach (MMA) (Group I). Demographic data, MV duration, length of ICU stay and mortality rates were recorded. The clinical pulmonary infection scores (CPISs), C-reactive protein (CRP) values, and the fraction of inspired oxygen (FiO2) and positive end-expiratory pressure (PEEP) values of the groups were compared at baseline, and at hours 48, 72 and 96.

RESULTS

In Group I, CPIS values significantly higher than Group II in 48th, 72nd and 96th hours (p < 0.05). In Group I, PEEP values and deep tracheal aspirate (DTA) culture growth rates significantly higher than Group II in 72nd and 96th hours (p < 0.05).

CONCLUSION

The continuous maintenance of ETC pressure using SCM reduced the incidence of VAP.

Topical antibiotic prophylaxis to reduce respiratory tract infections and mortality in adults receiving mechanical ventilation

BACKGROUND

Patients treated with mechanical ventilation in intensive care units (ICUs) have a high risk of developing respiratory tract infections (RTIs). Ventilator-associated pneumonia (VAP) has been estimated to affect 5% to 40% of patients treated with mechanical ventilation for at least 48 hours. The attributable mortality rate of VAP has been estimated at about 9%. Selective digestive decontamination (SDD), which consists of the topical application of non-absorbable antimicrobial agents to the oropharynx and gastroenteric tract during the whole period of mechanical ventilation, is often used to reduce the risk of VAP. A related treatment is selective oropharyngeal decontamination (SOD), in which topical antibiotics are applied to the oropharynx only. This is an update of a review first published in 1997 and updated in 2002, 2004, and 2009.

OBJECTIVES

To assess the effect of topical antibiotic regimens (SDD and SOD), given alone or in combination with systemic antibiotics, to prevent mortality and respiratory infections in patients receiving mechanical ventilation for at least 48 hours in ICUs.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), which contains the Cochrane Acute Respiratory Infections (ARI) Group's Specialised Register, PubMed, and Embase on 5 February 2020. We also searched the WHO ICTRP and ClinicalTrials.gov for ongoing and unpublished studies on 5 February 2020. All searches included non-English language literature. We handsearched references of topic-related systematic reviews and the included studies.

SELECTION CRITERIA

Randomised controlled trials (RCTs) and cluster-RCTs assessing the efficacy and safety of topical prophylactic antibiotic regimens in adults receiving intensive care and mechanical ventilation. The included studies compared topical plus systemic antibiotics versus placebo or no treatment; topical antibiotics versus no treatment; and topical plus systemic antibiotics versus systemic antibiotics.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane.

MAIN RESULTS

We included a total of 41 trials involving 11,004 participants (five new studies were added in this update). The minimum duration of mechanical ventilation ranged from 2 (19 studies) to 6 days (one study). Thirteen studies reported the mean length of ICU stay, ranging from 11 to 33 days. The percentage of immunocompromised patients ranged from 0% (10 studies) to 22% (1 study). The reporting quality of the majority of included studies was very poor, so we judged more than 40% of the studies as at unclear risk of selection bias. We judged all studies to be at low risk of performance bias, though 47.6% were open-label, because hospitals usually have standardised infection control programmes, and possible subjective decisions on who should be tested for the presence or absence of RTIs are unlikely in an ICU setting. Regarding detection bias, we judged all included studies as at low risk for the outcome mortality. For the outcome RTIs, we judged all double-blind studies as at low risk of detection bias. We judged five open-label studies as at high risk of detection bias, as the diagnosis of RTI was not based on microbiological exams; we judged the remaining open-label studies as at low risk of detection bias, as a standardised set of diagnostic criteria, including results of microbiological exams, were used. Topical plus systemic antibiotic prophylaxis reduces overall mortality compared with placebo or no treatment (risk ratio (RR) 0.84, 95% confidence interval (CI) 0.73 to 0.96; 18 studies; 5290 participants; high-certainty evidence). Based on an illustrative risk of 303 deaths in 1000 people this equates to 48 (95% CI 15 to 79) fewer deaths with topical plus systemic antibiotic prophylaxis. Topical plus systemic antibiotic prophylaxis probably reduces RTIs (RR 0.43, 95% CI 0.35 to 0.53; 17 studies; 2951 participants; moderate-certainty evidence). Based on an illustrative risk of 417 RTIs in 1000 people this equates to 238 (95% CI 196 to 271) fewer RTIs with topical plus systemic antibiotic prophylaxis. Topical antibiotic prophylaxis probably reduces overall mortality compared with no topical antibiotic prophylaxis (RR 0.96, 95% CI 0.87 to 1.05; 22 studies, 4213 participants; moderate-certainty evidence). Based on an illustrative risk of 290 deaths in 1000 people this equates to 19 (95% CI 37 fewer to 15 more) fewer deaths with topical antibiotic prophylaxis. Topical antibiotic prophylaxis may reduce RTIs (RR 0.57, 95% CI 0.44 to 0.74; 19 studies, 2698 participants; low-certainty evidence). Based on an illustrative risk of 318 RTIs in 1000 people this equates to 137 (95% CI 83 to 178) fewer RTIs with topical antibiotic prophylaxis. Sixteen studies reported adverse events and dropouts due to adverse events, which were poorly reported with sparse data. The certainty of the evidence ranged from low to very low.

AUTHORS' CONCLUSIONS

Treatments based on topical prophylaxis probably reduce respiratory infections, but not mortality, in adult patients receiving mechanical ventilation for at least 48 hours, whereas a combination of topical and systemic prophylactic antibiotics reduces both overall mortality and RTIs. However, we cannot rule out that the systemic component of the combined treatment provides a relevant contribution in the observed reduction of mortality. No conclusion can be drawn about adverse events as they were poorly reported with sparse data.

Efeitos da utilização do bundle na prevenção de pneumonia associada à ventilação mecânica: revisão integrativa

Introdução: A Pneumonia Associada à Ventilação Mecânica é uma infecção relacionada à assistência à saúde que predomina em unidades de terapia intensiva e que compromete a segurança do paciente. Objetivo: Identificar na literatura científica os efeitos do uso de Bundles na prevenção da Pneumonia Associada à Ventilação Mecânica em Unidade de Terapia Intensiva. Método: Revisão integrativa realizada com estudos disponibilizados nas bases dados online: Cumulative Index to Nursing and Allied Health Literature, Cocrhane, Literatura Latino-Americana e do Caribe em Ciências da Saúde, Medical Literature Analysis and Retrieval System Online, Scientific Electronic Library Online e Scopus. A busca dos estudos nas bases de dados se deu no período de dois de junho a 18 de julho de 2018, no idioma inglês ou português, sem limite de tempo de publicação, utilizando os termos dos DeCS e MeSH. O recrutamento foi realizado por dois pesquisadores independentes. Dos artigos selecionados, extraíram-se as informações: ano, país de origem, objetivo(s), grau de recomendação científica e tipo de estudo, intervenção, conformidade do uso do Bundle, principais resultados e conclusões. Resultados: Dentre as 20 publicações analisadas, 13 eram de diferentes países e a maioria dos estudos (n=18) constata que o uso de Blundes reduziu significativamente a taxa de Pneumonia Associada à Ventilação Mecânica, com impacto na redução da mortalidade, no tempo de internação e nos custos hospitalares. Os principais componentes de escolha para composição do pacote de cuidado foram à elevação da cabeceira e o protocolo de higiene oral. Conclusão: Apesar de existir espaço para estudos com maior grau de recomendação, o rol de evidências de muitos países indica que o uso de Bundles tem efeito positivo na prevenção da pneumonia associada a ventilação mecânica e também na melhoria de desempenho institucional, pela redução de custos hospitalares.

PROPHETIC: Prospective Identification of Pneumonia in Hospitalized Patients in the ICU

BACKGROUND

Pneumonia is the leading infection-related cause of death. The use of simple clinical criteria and contemporary epidemiology to identify patients at high risk of nosocomial pneumonia should enhance prevention efforts and facilitate development of new treatments in clinical trials.

RESEARCH QUESTION

What are the clinical criteria and contemporary epidemiology trends that are helpful in the identification of patients at high risk of nosocomial pneumonia?

STUDY DESIGN AND METHODS

Within the ICUs of 28 US hospitals, we conducted a prospective cohort study among adults who had been hospitalized >48 hours and were considered high risk for pneumonia (defined as treatment with invasive or noninvasive ventilatory support or high levels of supplemental oxygen). We estimated the proportion of high-risk patients who experienced the development of nosocomial pneumonia. Using multivariable logistic regression, we identified patient characteristics and treatment exposures that are associated with increased risk of pneumonia development during the ICU admission.

RESULTS

Between February 6, 2016, and October 7, 2016, 4,613 high-risk patients were enrolled. Among 1,464 high-risk patients (32%) who were treated for possible nosocomial pneumonia, 537 (37%) met the study pneumonia definition. Among high-risk patients, a multivariable logistic model was developed to identify key patient characteristics and treatment exposures that are associated with increased risk of nosocomial pneumonia development (c-statistic, 0.709; 95% CI, 0.686-0.731). Key factors associated with increased odds of nosocomial pneumonia included an admission diagnosis of trauma or cerebrovascular accident, receipt of enteral nutrition, documented aspiration risk, and receipt of systemic antibacterials within the preceding 90 days.

INTERPRETATION

Treatment for nosocomial pneumonia is common among patients in the ICU who are receiving high levels of respiratory support, yet more than one-half of patients who are treated do not fulfill standard diagnostic criteria for pneumonia. Application of simple clinical criteria may improve the feasibility of clinical trials of pneumonia prevention and treatment by facilitating prospective identification of patients at highest risk.

The impact of Candida spp airway colonization on clinical outcomes in patients with ventilator-associated pneumonia: A systematic review and meta-analysis

BACKGROUND

Previous studies have drawn different conclusions about the impact of Candida airway colonization on clinical outcomes in patients with ventilator-associated pneumonia (VAP).

METHODS

We searched PubMed, the Cochrane Library, Embase (via OVID), and Web of Science database. We included both retrospective and prospective observational studies. The mean difference (MD) or risk ratio (RR) with 95% confidence intervals (CI) were applied to assess the association between Candida colonization and clinical outcomes.

RESULTS

A total of 8 studies with 1,661 patients were pooled in our final studies. Compared with patients with VAP without Candida colonization, patients with Candida colonization had significantly longer durations of mechanical ventilation (MD, 1.93; 95% CI, 0.53-3.33). The intensive care unit (ICU) length of stay seems to be longer among Candida colonized patients than noncolonized patients, although the results were not so significant (MD, 1.15; 95% CI, -1.04 to 3.34). Patients with colonization had higher 28-day mortality and ICU mortality than those without colonization (28-day mortality: RR, 1.64; 95% CI, 1.27-2.12; ICU mortality: RR, 1.57; 95% CI, 1.26-1.94).

CONCLUSIONS

The presence of Candida spp airway colonization is associated with longer durations of mechanical ventilation, higher 28-day mortality, higher ICU mortality, and probably longer ICU length of stay compared with the absence of colonization in patients with VAP.

Diagnosis of ventilator-associated pneumonia in critically ill adult patients-a systematic review and meta-analysis

The accuracy of the signs and tests that clinicians use to diagnose ventilator-associated pneumonia (VAP) and initiate antibiotic treatment has not been well characterized. We sought to characterize and compare the accuracy of physical examination, chest radiography, endotracheal aspirate (ETA), bronchoscopic sampling cultures (protected specimen brush [PSB] and bronchoalveolar lavage [BAL]), and CPIS > 6 to diagnose VAP. We searched six databases from inception through September 2019 and selected English-language studies investigating accuracy of any of the above tests for VAP diagnosis. Reference standard was histopathological analysis. Two reviewers independently extracted data and assessed study quality. We included 25 studies (1639 patients). The pooled sensitivity and specificity of physical examination findings for VAP were poor: fever (66.4% [95% confidence interval [CI]: 40.7-85.0], 53.9% [95% CI 34.5-72.2]) and purulent secretions (77.0% [95% CI 64.7-85.9], 39.0% [95% CI 25.8-54.0]). Any infiltrate on chest radiography had a sensitivity of 88.9% (95% CI 73.9-95.8) and specificity of 26.1% (95% CI 15.1-41.4). ETA had a sensitivity of 75.7% (95% CI 51.5-90.1) and specificity of 67.9% (95% CI 40.5-86.8). Among bronchoscopic sampling methods, PSB had a sensitivity of 61.4% [95% CI 43.7-76.5] and specificity of 76.5% [95% CI 64.2-85.6]; while BAL had a sensitivity of 71.1% [95% CI 49.9-85.9] and specificity of 79.6% [95% CI 66.2-85.9]. CPIS > 6 had a sensitivity of 73.8% (95% CI 50.6-88.5) and specificity of 66.4% (95% CI 43.9-83.3). Classic clinical indicators had poor accuracy for diagnosis of VAP. Reliance upon these indicators in isolation may result in misdiagnosis and potentially unnecessary antimicrobial use.

Ventilator-associated pneumonia in adults: a narrative review

Ventilator-associated pneumonia (VAP) is one of the most frequent ICU-acquired infections. Reported incidences vary widely from 5 to 40% depending on the setting and diagnostic criteria. VAP is associated with prolonged duration of mechanical ventilation and ICU stay. The estimated attributable mortality of VAP is around 10%, with higher mortality rates in surgical ICU patients and in patients with mid-range severity scores at admission. Microbiological confirmation of infection is strongly encouraged. Which sampling method to use is still a matter of controversy. Emerging microbiological tools will likely modify our routine approach to diagnosing and treating VAP in the next future. Prevention of VAP is based on minimizing the exposure to mechanical ventilation and encouraging early liberation. Bundles that combine multiple prevention strategies may improve outcomes, but large randomized trials are needed to confirm this. Treatment should be limited to 7 days in the vast majority of the cases. Patients should be reassessed daily to confirm ongoing suspicion of disease, antibiotics should be narrowed as soon as antibiotic susceptibility results are available, and clinicians should consider stopping antibiotics if cultures are negative.

Emergence of Alveolar Consolidations in Serial Lung Ultrasound and Diagnosis of Ventilator-Associated Pneumonia

BACKGROUND

Lung ultrasound (LUS) has been reported as a promising diagnostic tool for ventilator-associated pneumonia (VAP), but patients with previous lung parenchyma commitment have been not studied.

PURPOSE

To evaluate whether the emergence of sonographic consolidations, rather than their presence, can improve the VAP diagnosis in a sample including patients with previous lung parenchyma diseases.

METHODS

Patients who completed 48 hours of mechanical ventilation were prospectively studied with daily LUS examinations. We checked the emergence of different consolidation types on the eve and on the day of a clinical suspicion of VAP. We elaborated an algorithm considering, sequentially, the emergence of (1) subpleural consolidations in anterior lung regions on the eve of suspicion; (2) lobar/sublobar consolidation in anterior lung regions on the day of suspicion; (3) lobar/sublobar consolidation with dynamic air bronchograms on the day of suspicion; and (4) any other lobar/sublobar consolidation on the day of suspicion in association with a positive Gram smear of endotracheal aspirate.

RESULTS

Of the 188 included patients, 60 were suspected and 33 confirmed VAP. The presence of sonographic consolidations at the clinical suspicion had no diagnostic value for VAP. The emergence of subpleural consolidations in anterior lung regions on the eve of suspicion had specificity of 95% (95% confidence interval [CI], 79%-99%). The emergence of lobar/sublobar consolidations in anterior lung regions on the day of suspicion had specificity of 100% (95% CI, 87%-100%). The emergence of lobar/sublobar consolidations with dynamic air bronchograms on the day of suspicion had specificity of 96% (95% CI, 81%-99%). Finally, the proposed algorithm had sensitivity of 63% (95% CI, 46%-77%) and specificity of 85% (95% CI, 67%-94%) for VAP.

CONCLUSIONS

The presence of sonographic consolidations was not accurate for VAP when patients with previous lung parenchyma commitment were included. However, serial LUS examinations detected the emergence of specific signs of VAP.

The prevalence of suspected ventilator-associated pneumonia in Scottish intensive care units

Ventilator-associated pneumonia is the most common healthcare-associated infection in mechanically ventilated patients. Despite this, accurate diagnosis of ventilator-associated pneumonia is difficult owing to the variety of criteria that exist. In this prospective national audit, we aim to quantify the existence of patients with suspected ventilator-associated pneumonia that would not be detected by our standard healthcare-associated infection screening process. Furthermore, we aim to assess the impact of tracheostomy insertion, subglottic drainage endotracheal tubes and chlorhexidine gel on ventilator-associated pneumonia rate. Of the 227 patients recruited, suspected ventilator-associated pneumonia occurred in 32 of these patients. Using the HELICS definition, 13/32 (40.6%) patients were diagnosed with ventilator-associated pneumonia (H-posVAP). Suspected ventilator-associated pneumonia rate was increased in our tracheostomy population, decreased in the subglottic drainage endotracheal tube group and unchanged in the chlorhexidine group. The diagnosis of ventilator-associated pneumonia remains a contentious issue. The formalisation of the HELICS criteria by the European CDC should allow standardised data collection throughout Europe, which will enable more consistent data collection and meaningful data comparison in the future. Our data add weight to the argument against routine oral chlorhexidine. The use of subglottic drainage endotracheal tubes in preventing ventilator-associated pneumonia is interesting and requires further investigation.

Clinical Trials Focusing on Drug Control and Prevention of Ventilator-Associated Pneumonia: A Comprehensive Analysis of Trials Registered on ClinicalTrials.gov

Objective: Clinical trials have emerged as the main force in driving the development of medicine. However, little is known about the current status of clinical trials regarding drug control and prevention of ventilator-associated pneumonia (VAP). This study aimed at providing a comprehensive landscape of these trials on the basis of ClinicalTrials.gov.

Methods: A cross-sectional, descriptive study of clinical trials on drug control and prevention of VAP which have been registered on the ClinicalTrials.gov up to 25^th August 2018 was conducted.

Results: A total of 109 eligible trials were identified. Trials were started from 1998 to 2018, and most trials focused on adult patients. More than half trials were completed, while only 11.9% trials had results available. Sample sizes were relatively large, with a median enrollment of 146. Universities were listed as the primary sponsor for 36.7% trials, industry for 28.4% trials and hospitals for 19.3% trials. Of the 109 VAP trials, 37 trials were from in Europe, 36 in North America and 27 in Asia. Among the 97 interventional trials, 32 were phase 3 trials, 21 were phase 4 trials, and 16 were phase 2 trials. Most interventional trials were randomized trials with a parallel assignment, and 57.7% trials were blinded. Of the 12 observational trials, 9 were cohort studies, and 10 trials were prosepctive studies. Drugs about oral care, preemptive antibiotics and probiotics were most investigated for prevention. A total of 61 trials investigated drugs for the treatment of VAP, mainly focused on antibiotics. A total of 36 kinds of antibiotics were investigated for monotherapy or combination therapy. Beta-lactams were most studied, followed by aminoglycosides and polypeptides.

Conclusion: Most clinical trials registered on ClinicalTrials.gov about drugs for VAP were interventional trials with the purpose for treatment. A high proportion of interventional trials were randomized, parallel assigned and masked. Our analysis highlights the need for improvement in completeness of study results on the ClinicalTrials.gov.

Preventing ventilator-associated pneumonia-a mixed-method study to find behavioral leverage for better protocol adherence

OBJECTIVE

Preventing ventilator-associated pneumonia (VAP) is an important goal for intensive care units (ICUs). We aimed to identify the optimal behavior leverage to improve VAP prevention protocol adherence.

DESIGN

Mixed-method study using adherence measurements to assess 4 VAP prevention measures and qualitative analysis of semi-structured focus group interviews with frontline healthcare practitioners (HCPs).

SETTING

The 6 ICUs in the 900-bed University Hospital Zurich in Zurich, Switzerland.Patients and participantsAdherence to VAP prevention measures were assessed in patients with a device for invasive ventilation (ie, endotracheal tube, tracheostomy tube). Participants in focus group interviews included a convenience samples of ICU nurses and physicians.

RESULTS

Between February 2015 and July 2017, we measured adherence to 4 protocols: bed elevation showed adherence at 27% (95% confidence intervals [CI], 23%-31%); oral care at 41% (95% CI, 36%-45%); sedation interruption at 81% (95% CI, 74%-85%); and subglottic suctioning at 88% (95% CI, 83%-92%). Interviews were analyzed first inductively according a grounded theory approach then deductively against the behavior change wheel (BCW) framework. Main behavioral facilitators belonged to the BCW component 'reflective motivation' (ie, perceived seriousness of VAP and self-efficacy to prevent VAP). The main barriers belonged to 'physical capability' (ie, lack of equipment and staffing and side-effects of prevention measures). Furthermore, 2 primarily technical approaches (ie, 'restructuring environment' and 'enabling HCP') emerged as means to overcome these barriers.

CONCLUSIONS

Our findings suggest that technical, rather than education-based, solutions should be promoted to improve VAP prevention. This theory-informed mixed-method approach is an effective means of guiding infection prevention efforts.

Update on ventilator-associated pneumonia

Ventilator-associated pneumonia (VAP) is the most frequent life-threatening nosocomial infection in intensive care units. The diagnostic is difficult because radiological and clinical signs are inaccurate and could be associated with various respiratory diseases. The concept of infection-related ventilator-associated complication has been proposed as a surrogate of VAP to be used as a benchmark indicator of quality of care. Indeed, bundles of prevention measures are effective in decreasing the VAP rate. In case of VAP suspicion, respiratory secretions must be collected for bacteriological secretions before any new antimicrobials. Quantitative distal bacteriological exams may be preferable for a more reliable diagnosis and therefore a more appropriate use antimicrobials. To improve the prognosis, the treatment should be adequate as soon as possible but should avoid unnecessary broad-spectrum antimicrobials to limit antibiotic selection pressure. For empiric treatments, the selection of antimicrobials should consider the local prevalence of microorganisms along with their associated susceptibility profiles. Critically ill patients require high dosages of antimicrobials and more specifically continuous or prolonged infusions for beta-lactams. After patient stabilization, antimicrobials should be maintained for 7-8 days. The evaluation of VAP treatment based on 28-day mortality is being challenged by regulatory agencies, which are working on alternative surrogate endpoints and on trial design optimization.

Relationship between hyperoxemia and ventilator associated pneumonia

Previous studies suggest a relationship between hyperoxemia and ventilator-associated pneumonia (VAP). Hyperoxemia is responsible for denitrogenation phenomena, and inhibition of surfactant production, promoting atelectasis in mechanically ventilated patients. Further, hyperoxemia impairs the efficacy of alveolar macrophages to migrate, phagocyte and kill bacteria. Oxygen can also cause pulmonary-specific toxic effect called hyperoxic acute lung injury leading to longer duration of mechanical ventilation. All these hyperoxic effects are well-known risk factors for VAP. A recent retrospective large single center study identified hyperoxemia as an independent risk factor for VAP. However, two recent randomized controlled trials evaluated the impact of conservative oxygen strategy versus a liberal strategy, but did not confirm the role of hyperoxemia in lower respiratory tract infection occurrence. In this review, we discuss animal and human studies suggesting a relationship between these two common conditions in mechanically ventilated patients and potential interventions that should be evaluated. Further large prospective studies in carefully selected groups of patients are required to confirm the potential role of hyperoxemia in VAP pathogenesis and to evaluate the impact of a conservative oxygen strategy vs. a conventional strategy on the incidence of VAP.

Accuracy and Applications of Lung Ultrasound to Diagnose Ventilator-Associated Pneumonia: A Systematic Review

BACKGROUND

Lung ultrasound (LUS) is an accurate tool to diagnose community-acquired pneumonia. However, it is not yet an established tool to diagnose ventilator-associated pneumonia (VAP).

PURPOSE

To assess the evidence about LUS in the diagnosis of VAP, we conducted a systematic review of the literature.

METHODS

We searched PubMed, Embase, Scopus, Web of Science, and LILACS. Two researchers independently selected the studies that met the inclusion criteria. Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tool was used to assess the quality of the studies. In a qualitative synthesis, 3 questions guided the review: Q1. What are the sonographic signs of VAP? Q2. How can LUS be combined with others tests or signs of VAP? Q3. What is the role of LUS in VAP screening?

MAIN RESULTS

Three studies (n = 377 patients) with different designs were included. In terms of Q1, the 3 studies assessed the accuracy of sonographic consolidations. In patients suspected for VAP, lobar or hemilobar consolidation alone was not sufficient to diagnose VAP but seems useful to exclude it. The most useful signs were small subpleural consolidations (sensitivity: 81%; specificity: 41%) and dynamic air bronchograms (sensitivity: 44%; specificity: 81%). Two studies were assessed for Q2, when the 2 signs above were included in a clinical score (Ventilator-associated Pneumonia Lung Ultrasound Score associated with quantitative culture of endotracheal aspirate-VPLUS-EAquant), the accuracy was amplified (sensitivity: 48% and specificity: 97% for score ≥4; sensitivity: 78% and specificity: 77% for score ≥3 points). Finally, regarding Q3, no studies have assessed the use of LUS in screening of VAP.

CONCLUSION

Small subpleural consolidations and dynamic air bronchograms were the most useful sonographic signs to diagnose VAP in suspected patients. Clinical scores including LUS had better diagnosis accuracy than LUS alone. There are no data on LUS for VAP screening.

Incidence, temporal trend and factors associated with ventilator-associated pneumonia in mainland China: a systematic review and meta-analysis

Background

Data to date is far from sufficient to describe the recent epidemiology of ventilator-associated pneumonia (VAP) in mainland China. This study aimed to estimate the overall incidence of VAP, with a special focus on its temporal trend and associated factors.

Methods

Meta-analyses of 195 studies published from 2010 to 2015 were conducted, followed by subgroup analyses by methodological quality, pre-defined setting characteristics and attributes of populations.

Results

The overall cumulative VAP incidence in mainland China was 23.8% (95% confidence interval (CI) 20.6–27.2%), with the results showing high heterogeneity. The pooled incidence densities were 24.14 (95% CI 21.19–27.51) episodes and 22.83 (95% CI 19.88–26.23) patients per 1000 ventilator-days. A decline in the cumulative incidence was observed from 2006 (49.5%, 95% CI 40.0–59.0%) to 2014 (19.6%, 95% CI 10.4–31.0%); differences in the incidence rates were also documented according to Chinese provinces and diagnostic criteria (p < 0.001). Older age (≥60 years), coma, re-intubation, tracheotomy and prolonged ventilation were the factors significantly associated with the occurrence of VAP.

Conclusions

The incidence of VAP remains high in mainland China but has decreased since 2006. The reported rates vary considerably across individual studies, probably due to variations in diagnosis and geographical region. More studies using standard definitions and cut-off points are needed to better clarify the epidemiology of VAP across the country.

Electronic supplementary material

The online version of this article (doi:10.1186/s12879-017-2566-7) contains supplementary material, which is available to authorized users.

Ventilator-Associated Pneumonia: The Role of Emerging Diagnostic Technologies

Antibiotic resistance has emerged as a key determinant of outcome in patients with serious infections along with the virulence of the underlying pathogen. Within the intensive care unit (ICU) setting, ventilator-associated pneumonia (VAP) is a common nosocomial infection that is frequently caused by multidrug-resistant bacteria. Antimicrobial resistance is a growing challenge in the care of critically ill patients. Escalating rates of antibiotic resistance add substantially to the morbidity, mortality, and cost related to infection in the ICU. Both gram-positive organisms, such as methicillin-resistant Staphylococcus aureus and vancomycin-intermediate S. aureus, and gram-negative bacteria, including Pseudomonas aeruginosa, Acinetobacter species, carbapenem-resistant Enterobacteriaceae, such as the Klebsiella pneumoniae carbapenemase-producing bacteria, and extended spectrum β-lactamase organisms, have contributed to the escalating rates of resistance seen in VAP and other nosocomial infections. The rising rates of antimicrobial resistance have led to the routine empiric administration of broad-spectrum antibiotics even when bacterial infection is not documented. Moreover, there are several new broader-spectrum antibiotics that have recently become available and others scheduled for approval in the near future. The challenge to ICU clinicians is how to most effectively utilize these agents to maximize patient benefits while minimizing further emergence of resistance. Use of rapid diagnostics may hold the key for achieving this important balance. There is an urgent need for integrating the administration of new and existing antibiotics with the emerging rapid diagnostic technologies in a way that is both cost-effective and sustainable for the long run.

Incidence and Characteristics of Ventilator-Associated Events Reported to the National Healthcare Safety Network in 2014

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Objective:

Ventilator-associated event surveillance was introduced in the National Healthcare Safety Network in 2013, replacing surveillance for ventilator-associated pneumonia in adult inpatient locations. We determined incidence rates and characteristics of ventilator-associated events reported to the National Healthcare Safety Network.

Design, Setting, and Patients:

We analyzed data reported from U.S. healthcare facilities for ventilator-associated events that occurred in 2014, the first year during which ventilator-associated event surveillance definitions were stable. We used negative binomial regression modeling to identify healthcare facility and inpatient location characteristics associated with ventilator-associated events. We calculated ventilator-associated event incidence rates, rate distributions, and ventilator utilization ratios in critical care and noncritical care locations and described event characteristics.

Measurements and Main Results:

A total of 1,824 healthcare facilities reported 32,772 location months of ventilator-associated event surveillance data to the National Healthcare Safety Network in 2014. Critical care unit pooled mean ventilator-associated event incidence rates ranged from 2.00 to 11.79 per 1,000 ventilator days, whereas noncritical care unit rates ranged from 0 to 14.86 per 1,000 ventilator days. The pooled mean proportion of ventilator-associated events defined as infection-related varied from 15.38% to 47.62% in critical care units. Pooled mean ventilator utilization ratios in critical care units ranged from 0.24 to 0.47.

Conclusions:

We found substantial variability in ventilator-associated event incidence, proportions of ventilator-associated events characterized as infection-related, and ventilator utilization within and among location types. More work is needed to understand the preventable fraction of ventilator-associated events and identify patient care strategies that reduce ventilator-associated events.

Improving the quality of the intensive care follow-up of ventilated patients during a national registration program

OBJECTIVES

The Belgian Public Health Organization is concerned with rates of hospital-acquired infections like ventilator-associated pneumonia (VAP). Implementing best practice guidelines for these nosocomial infections has variable success in the literature. This retrospective study was undertaken to see whether implementation of the evidence-based practices as a bundle was feasible, would influence compliance, and could reduce the rates of VAP.

STUDY DESIGN

We utilized easily collectable data about regular care to rapidly assess whether interventions already in place were effectively successfully applied. This avoided cumbersome data collection and review.

METHODS

Retrospective compliance rates and VAP ratios were compared using z tests with P-values < 0.05 considered statistically significant. This data review attempted to examine the impact of education campaigns, staff meetings, in-services, physician checklist, nurse checklist, charge nurse checklist implementation, systematic VAP bundle application, and systematic protocols for oral care and sedation protocols. Additionally, VAP ratio could be registered by the participating centers.

RESULTS

A total of 10,211 intensive care unit (ICU) patients were included in the study which represents 66,817 ICU days under artificial ventilation with an endotracheal tube. The general compliance for VAP bundle raised from VAP was 61% in February 2012 and 74.16% in December 2012 (P < 0.001). The incidence rate of VAP went from 8.34 occurrences/1000 vent days in 2009 to 4.78 occurrences/1000 vent days in 2012 (P < 0.001-Pearson test).

CONCLUSIONS

Efforts to improve physician and staff education, and checklist implementation resulted in an increase in compliance for VAP bundle and a decrease in VAP ratio. This study confirms the applicability of best practice guidelines about regular care but results on VAP incidence have to be confirmed.