Does ventilator-associated event surveillance detect ventilator-associated pneumonia in intensive care units? A systematic review and meta-analysis

Outcomes associated with ventilator-associated events (VAE), respiratory infections (VARI), pneumonia (VAP) and tracheobronchitis (VAT) in ventilated pediatric ICU patients: A multicentre prospective cohort study

OBJECTIVES

An objective categorization of respiratory infections based on outcomes is an unmet clinical need. Ventilator-associated pneumonia and tracheobronchitis remain used in clinical practice, whereas ventilator-associated events (VAE) are limited to surveillance purposes.

RESEARCH METHODOLOGY/DESIGN

This was a secondary analysis from a multicentre observational prospective cohort study. VAE were defined as a sustained increase in minimum Oxygen inspired fraction (FiO2) and/or Positive end-expiratory pressures (PEEP) of ≥ 0.2/2 cm H2O respectively, or an increase of 0.15 FiO2 + 1 cm H20 positive end-expiratory pressures for ≥ 1 calendar-day.

SETTING

15 Paediatric Intensive Care Units.

MAIN OUTCOME MEASURES

Mechanical ventilation duration, intensive care and hospital length of stay; (LOS) and mortality.

RESULTS

A cohort of 391 ventilated children with an age (median, [Interquartile Ranges]) of 1 year[0.2-5.3] and 7 days[5-10] of mechanical ventilation were included. Intensive care and hospital stays were 11 [7-19] and 21 [14-39] days, respectively. Mortality was 5.9 %. Fifty-eight ventilator-associated respiratory infections were documented among 57 patients: Seventeen (29.3 %) qualified as ventilator-associated pneumonia (VAP) and 41 (70.7 %) as ventilator-associated tracheobronchitis (VAT). Eight pneumonias and 16 tracheobronchitis (47 % vs 39 %,P = 0.571) required positive end-expiratory pressure or oxygen increases consistent with ventilator-associated criteria. Pneumonias did not significantly impact on outcomes when compared to tracheobronchitis. In contrast, infections (pneumonia or tracheobronchitis) following VAEs criteria were associated with > 6, 8 and 15 extra-days of ventilation (16 vs 9.5, P = 0.001), intensive care stay (23.5 vs 15; P = 0.004) and hospital stay (39 vs 24; P = 0.015), respectively.

CONCLUSION

When assessing ventilated children with respiratory infections, VAE apparently is associated with higher ventilator-dependency and LOS compared with pneumonia or tracheobronchitis.

IMPLICATIONS FOR PRACTICE

Incorporating the modification of ventilatory settings for further categorization of the respiratory infections may facilitate therapeutic management among ventilated patients.

Relationship between microaspiration and ventilator-associated events: A post-hoc analysis of a randomized controlled trial

OBJECTIVE

The relationship between ventilator-associated events (VAE) and microaspiration in intubated patients has not be studied. The objective of this study was to evaluate the relationship between abundant microaspiration of oropharyngeal secretions or gastric contents and the incidence of VAE.

PATIENTS AND METHODS

This was a post hoc analysis of the BESTCUFF study, which was a multicenter, cluster randomized, cross-over, controlled, open-label trial in adult patients ventilated for over 48 h. All tracheal aspirates were sampled for 48 h following enrollment, with quantitative measurement of pepsin and alpha-amylase. VAE were identified using National Healthcare Safety Network criteria, based on PEEP or FiO2 variations compared to stable parameters in previous days. The primary objective was to assess the relationship between abundant global microaspiration and the incidence of VAE, adjusted for pre-specified confounding factors (sex, SAPS II score and Glasgow coma scale).

RESULTS

261 patients were included, of which 31 (11.9%) developed VAE, with an overall median age of 65 (interquartile range 52-74), a majority of male patients (164, 62.8%), a median SAPS II score of 50 [40-61], a median SOFA score of 8 [5-11], and acute respiratory failure as main reason for ICU admission (117, 44.8%).The incidence of VAE was not significantly associated with abundant global microaspiration (adjusted cause-specific hazard ratio (cHR): 1.55 [0.46-5.17), abundant gastric microaspiration (adjusted cHR: 1.24 [0.61-2.53), or with abundant oropharyngeal microaspiration (adjusted HR: 1.07 [0.47-2.42]).

CONCLUSIONS

Our results suggest no significant association between abundant global, gastric or oropharyngeal microaspiration and the incidence of VAE.

IMPLICATIONS FOR CLINICAL PRACTICE

This study underscores that measuring microaspiration in intubated critically ill patients might not be useful to predict the diagnosis of VAE or to evaluate interventions aiming at preventing these complications.

Ventilator-Associated Pneumonia, Ventilator-Associated Events, and Nosocomial Respiratory Viral Infections on the Leeside of the Pandemic

The COVID-19 pandemic has had an unprecedented impact on population health and hospital operations. Over 7 million patients have been hospitalized for COVID-19 thus far in the United States alone. Mortality rates for hospitalized patients during the first wave of the pandemic were > 30%, but as we enter the fifth year of the pandemic hospitalizations have fallen and mortality rates for hospitalized patients with COVID-19 have plummeted to 5% or less. These gains reflect lessons learned about how to optimize respiratory support for different kinds of patients, targeted use of therapeutics for patients with different manifestations of COVID-19 including immunosuppressants and antivirals as appropriate, and high levels of population immunity acquired through vaccines and natural infections. At the same time, the pandemic has helped highlight some longstanding sources of harm for hospitalized patients including hospital-acquired pneumonia, ventilator-associated events (VAEs), and hospital-acquired respiratory viral infections. We are, thankfully, on the leeside of the pandemic at present; but the large increases in ventilator-associated pneumonia (VAP), VAEs, bacterial superinfections, and nosocomial respiratory viral infections associated with the pandemic beg the question of how best to prevent these complications moving forward. This paper reviews the burden of hospitalization for COVID-19, the intersection between COVID-19 and both VAP and VAEs, the frequency and impact of hospital-acquired respiratory viral infections, new recommendations on how best to prevent VAP and VAEs, and current insights into effective strategies to prevent nosocomial spread of respiratory viruses.

Ventilator-associated events in adults: A secondary analysis assessing the impact of monitoring ventilator settings on outcomes

BACKGROUND

Ventilator-associated events (VAE) is a tier implemented for surveillance by the CDC in the USA. Implementation usefulness for clinical decisions is unknown.

METHODS

We conducted a secondary analysis from a prospective, multicentre, international study, to assess the impact on outcomes of using tiers with shorter follow-up (VAE24), lower oxygenation requirements (light-VAE) or both (light VAE24).

RESULTS

A cohort of 261 adults with 2706 ventilator-days were included. The median (IQR) duration of mechanical ventilation (MV) was 9 days (5-21), and the median (IQR) length of stay in the intensive care unit (ICU) was 14 days (8-26). A VAE tier was associated with a trend to increase from 32% to 44% in the ICU mortality rates. VAE Incidence was 24 per 1,000 ventilator-days, being increased when reduced the oxygenation settings requirement (35 per 1,000 ventilator-days), follow-up (41 per 1,000 ventilator-days) or both (55 per 1,000 ventilator-days). A VAE tier was associated with 13 extra (21 vs. 8) days of ventilation, 11 (23 vs. 12) ICU days and 7 (31 vs. 14) hospitalization days, outperforming the modified tiers' performance.

CONCLUSIONS

The modification of ventilator settings (consistent with ventilator-associated events) was associated with worse outcomes among adults with prolonged mechanical ventilation. Monitoring ventilator-associated events at the bedside represents a new tool for quality improvement.

Early prediction of ventilator-associated pneumonia with machine learning models: A systematic review and meta-analysis of prediction model performance✰

BACKGROUND

Machine learning-based prediction models can catalog, classify, and correlate large amounts of multimodal data to aid clinicians at diagnostic, prognostic, and therapeutic levels. Early prediction of ventilator-associated pneumonia (VAP) may accelerate the diagnosis and guide preventive interventions. The performance of a variety of machine learning-based prediction models were analyzed among adults undergoing invasive mechanical ventilation.

METHODS

This systematic review and meta-analysis was conducted in accordance with the Cochrane Collaboration. Machine learning-based prediction models were identified from a search of nine multi-disciplinary databases. Two authors independently selected and extracted data using predefined criteria and data extraction forms. The predictive performance, the interpretability, the technological readiness level, and the risk of bias of the included studies were evaluated.

RESULTS

Final analysis included 10 static prediction models using supervised learning. The pooled area under the receiver operating characteristics curve, sensitivity, and specificity for VAP were 0.88 (95 % CI 0.82-0.94, I2 98.4 %), 0.72 (95 % CI 0.45-0.98, I2 97.4 %) and 0.90 (95 % CI 0.85-0.94, I2 97.9 %), respectively. All included studies had either a high or unclear risk of bias without significant improvements in applicability. The care-related risk factors for the best performing models were the duration of mechanical ventilation, the length of ICU stay, blood transfusion, nutrition strategy, and the presence of antibiotics.

CONCLUSION

A variety of the prediction models, prediction intervals, and prediction windows were identified to facilitate timely diagnosis. In addition, care-related risk factors susceptible for preventive interventions were identified. In future, there is a need for dynamic machine learning models using time-depended predictors in conjunction with feature importance of the models to predict real-time risk of VAP and related outcomes to optimize bundled care.

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

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

Prevalence of ventilator-associated events and antibiogram of bacterial isolates of ventilator-associated pneumonia in a tertiary care hospital of Uttarakhand

Background and Objectives

Despite progress in diagnosing and managing ventilator-associated pneumonia (VAP), ongoing monitoring of ventilator-associated events (VAE) is crucial due to VAP's persistent prominence as the primary cause of Hospital-Acquired Infection (HAI) among Intensive Care unit patients. This study was done to illuminate the prevalence of VAE and antibiogram of bacterial isolates of VAP in a tertiary care hospital of Uttarakhand.

Materials and Methods

This cross-sectional study focused on ICU patients. Adult patients ventilated for > 2 days were monitored daily, with VAE data analyzed using Center of Disease Control & Prevention (CDC) criteria. Specimens were sent to the Microbiology Department and cultured on Blood agar and MacConkey agar. Identification and antimicrobial profiles of isolates were determined using Vitek-2 Compact.

Results

1220 ventilated individuals were assessed in total. VAE was diagnosed in 6.4% (78/1220) of the patients, the same later developed ventilator associated condition (VAC), 74 developed the infection-related VAC (IVAC), and 60 developed the possible/probable VAP (PVAP) among the 78 VAE cases. Klebsiella pneumoniae (35%), Acinetobacter baumannii (33%), and Pseudomonas aeruginosa (16%) were the most common isolated organisms. Colistin (57%) was the most effective against Klebsiella pneumoniae, followed by amikacin (28.5%) and trimethoprim+sulfamethoxazole (24%). Pseudomonas aeruginosa was most susceptible to imipenem (70%), meropenem, cefoperazone+sulbactam, and colistin (60%). Acinetobacter baumannii was most susceptible to colistin (85%), tigecycline (65%), and trimethoprim+sulfamethoxazole (25%).

Conclusion

The most common cause of HAI is VAP. The purpose of this study is to determine the importance of starting suitable antibiotics early for prognosis and the difficulty of diagnosing VAP.

VAP risk index: Early prediction and hospital phenotyping of ventilator-associated pneumonia using machine learning

BACKGROUND

Ventilator-associated pneumonia (VAP) is a leading cause of morbidity and mortality in intensive care units (ICUs). Early identification of patients at risk of VAP enables early intervention, which in turn improves patient outcomes. We developed a predictive model for individualized risk assessment utilizing machine learning to identify patients at risk of developing VAP.

METHODS

The Philips eRI dataset, a multi-institution electronic medical record (EMR), was used for model development. For adult (≥18y) patients, we propose a set of criteria using indications of the start of a new antibiotic treatment temporally contiguous to a microbiological test to mark suspected infection events, of which those with a positive culture are labeled as presumed VAP if 1) the event occurs at least 48 h after intubation, and 2) there are no indications of community-acquired pneumonia (CAP) or other hospital-acquired infections (HAI) in the patient charts. The resulting VAP and no-VAP (control) cases were then used to build an ensemble of decision trees to predict the risk of VAP in the next 24 h using data on patients' demographics, vitals, labs, and ventilator settings.

RESULTS

The resulting model predicts the development of VAP 24 h in advance with an AUC of 76 % and AUPRC of 75 %. Additionally, we group hospitals that are similar in healthcare processes into distinct clusters and characterize VAP prediction for the identified hospital clusters. We show inter-hospital (teaching status and healthcare processes) and cohort-specific (age groups, gender, early vs late VAP, ICU mortality status) differences in VAP prediction and associated symptomologies.

CONCLUSIONS

Our proposed VAP criteria use clinical actions to mark incidences of presumed VAP infection, which enables the development of models for early detection of these events. We curated a patient cohort using these criteria and used it to build a model for predicting impending VAP events prior to clinical suspicions. We present a clustering approach for tailoring the VAP prediction model for different hospital types based on their EMR data characteristics. The model provides an instantaneous risk score that allows early interventions and confirmatory diagnostic actions.

Evaluation of ICUs and weight of quality control indicators: an exploratory study based on Chinese ICU quality data from 2015 to 2020

This study aimed to explore key quality control factors that affected the prognosis of intensive care unit (ICU) patients in Chinese mainland over six years (2015-2020). The data for this study were from 31 provincial and municipal hospitals (3425 hospital ICUs) and included 2 110 685 ICU patients, for a total of 27 607 376 ICU hospitalization days. We found that 15 initially established quality control indicators were good predictors of patient prognosis, including percentage of ICU patients out of all inpatients (%), percentage of ICU bed occupancy of total inpatient bed occupancy (%), percentage of all ICU inpatients with an APACHE II score ⩾15 (%), three-hour (surviving sepsis campaign) SSC bundle compliance (%), six-hour SSC bundle compliance (%), rate of microbe detection before antibiotics (%), percentage of drug deep venous thrombosis (DVT) prophylaxis (%), percentage of unplanned endotracheal extubations (%), percentage of patients reintubated within 48 hours (%), unplanned transfers to the ICU (%), 48-h ICU readmission rate (%), ventilator associated pneumonia (VAP) (per 1000 ventilator days), catheter related blood stream infection (CRBSI) (per 1000 catheter days), catheter-associated urinary tract infections (CAUTI) (per 1000 catheter days), in-hospital mortality (%). When exploratory factor analysis was applied, the 15 indicators were divided into 6 core elements that varied in weight regarding quality evaluation: nosocomial infection management (21.35%), compliance with the Surviving Sepsis Campaign guidelines (17.97%), ICU resources (17.46%), airway management (15.53%), prevention of deep-vein thrombosis (14.07%), and severity of patient condition (13.61%). Based on the different weights of the core elements associated with the 15 indicators, we developed an integrated quality scoring system defined as F score=21.35%xnosocomial infection management + 17.97%xcompliance with SSC guidelines + 17.46%×ICU resources + 15.53%×airway management + 14.07%×DVT prevention + 13.61%×severity of patient condition. This evidence-based quality scoring system will help in assessing the key elements of quality management and establish a foundation for further optimization of the quality control indicator system.

Narrative Review of the Epidemiology of Hospital-Acquired Pneumonia and Ventilator-Associated Pneumonia in Gulf Cooperation Council Countries

Hospital-acquired pneumonia (HAP) and ventilator-associated pneumonia (VAP) are the most common healthcare-associated infections, with rates varying between countries. Antimicrobial resistance (AMR) among common HAP/VAP pathogens has been reported, and multidrug resistance (MDR) is of further concern across Middle Eastern countries. This narrative review summarizes the incidence and pathogens associated with HAP/VAP in hospitals across Gulf Cooperation Council (GCC) countries. A PubMed literature search was limited to available data on HAP or VAP in patients of any age published within the past 10 years. Reviews, non-English language articles, and studies not reporting HAP/VAP data specific to a GCC country were excluded. Overall, 41 articles, a majority of which focused on VAP, were selected for inclusion after full-text screening. Studies conducted over multiple years showed a general reduction in VAP rates over time, with Gram-negative bacteria the most commonly reported pathogens. Gram-negative isolates reported across GCC countries included Acinetobacter baumannii, Pseudomonas aeruginosa, and Klebsiella pneumoniae. Rates of AMR varied widely among studies, and MDR among A. baumannii, K. pneumoniae, Escherichia coli, P. aeruginosa, and Staphylococcus aureus isolates was commonly reported. In Saudi Arabia, between 2015 and 2019, rates of carbapenem resistance among Gram-negative bacteria were 19-25%; another study (2004-2009) reported antimicrobial resistance rates in Acinetobacter species (60-89%), P. aeruginosa (13-31%), and Klebsiella species (100% ampicillin, 0-13% other antimicrobials). Although limited genotype data were reported, OXA-48 was found in ≥ 68% of patients in Saudi Arabia with carbapenem-resistant Enterobacteriaceae infections. Ventilator utilization ratios varied across studies, with rates up to 0.9 reported in patients admitted to adult medical/surgical intensive care units in both Kuwait and Saudi Arabia. VAP remains a burden across GCC countries albeit with decreases in rates over time. Evaluation of prevention and treatment measures and implementation of a surveillance program could be useful for the management of HAP and VAP.

Epidemiology and outcomes of ventilator-associated events in critically ill children: Evaluation of three different definitions

OBJECTIVE

Ventilator-associated pneumonia (VAP) is one of the most common healthcare-associated infections in pediatric intensive care units (PICUs), but its definite diagnosis remains controversial. The CDC Ventilator-Associated Event (VAE) module (validated in adults) constitutes a new approach for VAP surveillance.

DESIGN

We described epidemiological characteristics of PICU VAE cases, investigated possible risk factors, and evaluated 3 different sets of diagnostic VAE criteria.

SETTING

This study was conducted in a PICU in a tertiary-care general hospital in northern Greece during 2017-2019.

PATIENTS

The study included patients aged 35 days-16 years who received mechanical ventilation.

METHODS

From medical records, we retrieved epidemiological data, clinical data, and laboratory characteristics as well as ventilator settings for our analysis. We assessed "oxygen deterioration" for the tier 1 CDC VAE module using 3 sets of diagnostic criteria: (1) CDC adult VAE criteria [increase of daily minimum fraction of inspired oxygen (FiO2) ≥ 0.2 or positive end expiratory pressure (PEEP) ≥ 3 cmH2O for 2 days], (2) the US pediatric VAE criteria [increase of FiO2 ≥ 0.25 or mean airway pressure (MAP) ≥ 4 cmH2O for 2 days], and (3) the European pediatric VAE criteria (increase of FiO2 ≥ 0.2 or PEEP ≥ 2 cmH2O for 1 day or increase of FiO2 ≥ 0.15 and PEEP ≥ 1 cm H2O for 1 day).

RESULTS

Among 326 children admitted to the PICU, 301 received mechanical ventilation. The incidence rate according to the CDC adult VAE criteria was 4.7 per 1,000 ventilator days. For the US pediatric VAE criteria the incidence rate was 6 per 1,000 ventilator days. For the European pediatric VAE criteria the incidence rate was 9.7 per 1,000 ventilator days. These results revealed statistically significant correlation of all 3 algorithms with adverse outcomes, including mortality.

CONCLUSIONS

All VAE algorithms were associated with higher mortality rates. Our findings highlight the need for a unified pediatric VAE definition to improve preventive strategies.

Recommendations for change in infection prevention programs and practice

Fifty years of evolution in infection prevention and control programs have involved significant accomplishments related to clinical practices, methodologies, and technology. However, regulatory mandates, and resource and research limitations, coupled with emerging infection threats such as the COVID-19 pandemic, present considerable challenges for infection preventionists. This article provides guidance and recommendations in 14 key areas. These interventions should be considered for implementation by United States health care facilities in the near future.

APACHE scoring system and pressure injury risk for intensive care patients: A systematic review and meta-analysis

The present study was designed to determine the association between Acute Physiology and Chronic Health Evaluation (APACHE) scale and elevated pressure injure (PI) risk in intensive care units (ICU) and also evaluate the predictive value of APACHE score in PI patients. Comprehensive strategies were used to search studies from PubMed, Web of Science, and Ovid Embase electronic databases for observational studies that provided data about APACHE scores related to PI in ICU. Eligible studies were selected based on inclusion and exclusion criteria. The pooled SMD with 95% confidence intervals were calculated. A summary ROC curve was plotted to calculate area under curve (AUC) for APACHE-II (15-20). Twenty-one studies involving 11,102 patients who met selection criteria were included. The 11.0% of patients (1229/11102) in ICU developed PIs. Overall, the PI group had a higher score compared with the non-PI group in the APACHE II (22.1 ± 8.0 vs. 14.5 ± 7.4, mean ± SD). The APACHE-III of PI patients was significantly more than that in the non-PI group (79.9 ± 25.6 vs. 59.9 ± 30.4, mean ± SD). The pooled SMD was 0.82 (95% CI: 0.58-1.06, I²  = 91.7%, p-value < 0.001). The subgroup analysis revealed that the risk of PIs did not vary with the type of APACHE score (II, III, IV) and the type of study design (case-control, cross-sectional, cohort, longitudinal study). Proportion of males (I²  = 91.68%, p value = 0.090), publish year (I²  = 91.96%, p value = 0.187) and mean age of patients (I²  = 91.96%, p value = 0.937) were not the sources of heterogeneity. APACHE-II (15-20) achieves the best predictive performance in PI, and the prediction accuracy was balanced with equal sensitivity and specificity (Sen: 0.72, 0.62-0.80; Spec: 1.72, 1.25-2.38). In conclusion, higher APACHE scores are frequently accompanied by a higher incidence of PI among critical-care patients. APACHE-II scores (15-20) satisfactorily predicted PI, and strategies to prevent PI should be aggressively implemented.

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.

Ventilator-associated events in children: A multicentre prospective cohort study

BACKGROUND

The Centres for Disease Control and Prevention (CDC) broadened the focus of surveillance from ventilator-associated pneumonia to ventilator-associated event (VAE) for quality purposes. No paediatric definition of VAE (PaedVAE) has been accurately validated. We aimed to analyse the incidence and impact on patient outcomes resulting from the application of the adult and two paediatric VAE (PaedVAE) criteria.

SECONDARY OBJECTIVE

to evaluate VAE/PaedVAE as factors associated with increased duration of mechanical ventilation (MV) and Paediatric Intensive Care Unit (PICU) stay.

METHODS

Multicentre observational prospective cohort study in 15 PICUs in Spain. VAEs were assessed using the 2013/2015 CDC classification. PaedVAE were assessed using the CDC definition based on mean airway pressure (MAP-PaedVAE) versus a paediatric definition based on positive end-expiratory pressure (PEEP-PaedVAE). Children who underwent MV ≥ 48 h were included.

RESULTS

A total of 3626 ventilator-days in 391 patients were analysed. The incidence of VAE, MAP-PaedVAE and PEEP-PaedVAE was 8.55, 5.24 and 20.96 per 1000 ventilator-days, respectively. The median time [IQR] for VAE, MAP-PaedVAE and PEEP-PaedVAE development from the MV onset was 4 [3-12.5], 4 [3-14], and 5 [3-7.75] days, respectively. Among survivors, all three were associated with increased MV duration (> 7 days) and PICU stay (> 10 days) at univariate analysis. Multivariate analysis showed that PEEP-PaedVAE was the only definition independently associated with MV above 7 days [OR = 4.86, 95% CI (2.41-10.11)] and PICU stay [OR = 3.49, 95% CI (1.68-7.80)] above ten days, respectively.

CONCLUSIONS

A VAE definition based on slight PEEP increases should be preferred for VAE surveillance in children.

Ventilator-associated Events Surveillance in a Trauma Intensive Care Unit: A Prospective Study of Incidence, Predictive Values, Sensitivity, Specificity, Accuracy, and Concordance with Ventilator-associated Pneumonia

Introduction

The Centres for Disease Control and Prevention (CDC) introduced a new definition of ventilator-associated events (VAEs) in 2013 in place of longstanding ventilator-associated pneumonia (VAP) definition. Three entities under VAE, ventilator-associated condition (VAC), infection-related ventilator-associated complication (IVAC), and possible ventilator-associated pneumonia (PVAP), were introduced.

Objectives

To assess the incidence of all VAEs in a tertiary care trauma ICU and to find the predictive value of VAE and sensitivity of VAE definitions for VAP.

Design

Cohort prospective study at trauma intensive care unit (ICU) of PGIMER, Chandigarh, from July 2018 till June 2019.

Materials and methods

Patients admitted in trauma ICU were checked for VAP and VAE criteria defined by CDC.

Results

Four hundred and sixty five patients were observed. Around 378 patients were included in the study with 4046 patient days and 3031 mechanical ventilation (MV) days. Incidence rate of PVAP, IVAC, VAC, and VAP was 2.97, 6.60, 10.23, and 9.24 per 1000 ventilator days, respectively. Sensitivity, specificity, positive predictive value, and negative predictive value (NPV) of diagnosing VAP were 0.61, 0.97, 0.68, and 0.97 for VAC; 0.80, 0.97, 0.57, and 0.99 for IVAC; and 0.78, 0.94, 0.25, and 0.9 for PVAP, respectively. Kendall's W test showed that there was very poor concordance between VAP and VAE.

How to cite this article

Kaur K, Jain K, Biswal M, Dayal SK. Ventilator-associated Events Surveillance in a Trauma Intensive Care Unit: A Prospective Study of Incidence, Predictive Values, Sensitivity, Specificity, Accuracy, and Concordance with Ventilator-associated Pneumonia. Indian J Crit Care Med 2022;26(5):584–590.

Risk Factors and Nursing Countermeasures of Ventilator-Associated Pneumonia in Children in the Intensive Care Unit

Objective

This study discussed and analyzed the risk factors and nursing countermeasures of ventilator-associated pneumonia (VAP) in the children intensive care unit (ICU).

Methods

In this study, 155 children with mechanical ventilation in the pediatric intensive care unit from Oct. 2018 to Oct. 2020 were chosen as research objects. We retrospectively analyzed the clinical data of children and divided them into VAP groups and non-VAP groups according to the occurrence of VAP. Subsequently, we adopted a univariate and multivariate logistic regression model to analyze and clarify the risk factors of VAP and formulated the corresponding nursing countermeasures.

Results

49 cases of total research objects had occurred VAP, with an infection rate of 31.62%. The primary pathogenic bacteria were Gram-negative bacteria (43/70, 61.43%). According to multivariate logistic regression analysis, the duration of mechanical ventilation, invasive procedures, and application of hormones and antacids are all independent risk factors for VAP in pediatric ICU. The VPA group had longer hospital stay than the non-VAP group, and the difference was statistically significant ((20.92 ± 4.16)d, (15.24 ± 3.77)d, t = 8.4383, P ≤ 0.001). The hospitalization cost of the VPA group was substantially higher than that of the non-VAP Group ((45.8 ± 10.4) thousand Yuan, (33.2 ± 4.3) thousand Yuan, t = 10.6822, P ≤ 0.001).

Conclusion

Children admitted to the pediatric ICU have a high VAP incidence. The primary pathogenic bacteria are Gram-negative bacteria. As the occurrence of VAP is closely related to a variety of factors, we should take targeted nursing countermeasures to reduce the duration of mechanical ventilation and the frequency of invasive operations and use the hormone and antacids rationally to reduce the risk of VAP and improve the prognosis.

"HAP and VAP after Guidelines"

Nosocomial pneumonia is associated with worsened prognosis when diagnosed in intensive care unit (ICU), ranging from 12 to 48% mortality. The incidence rate of ventilation-acquired pneumonia tends to decrease below 15/1,000 intubation-day. Still, international guidelines are heterogeneous about diagnostic criteria because of inaccuracy of available methods. New entities have thus emerged concerning lower respiratory tract infection, namely ventilation-acquired tracheobronchitis (VAT), or ICU-acquired pneumonia (ICUAP), eventually requiring invasive ventilation (v-ICUAP), according to the type of ventilation support. The potential discrepancy with non-invasive methods could finally lead to underdiagnosis in almost two-thirds of non-intubated patients. Delayed diagnostic could explain in part the 2-fold increase in mortality of penumonia when invasive ventilation is initiated. Here we discuss the rationale underlying this new classification.Many situations can lead to misdiagnosis, even more when the invasive mechanical ventilation is initiated. The chest radiography lacks sntivity and specificity for diagnosing pneumonia. The place of chest computed tomography and lung ultrasonography for routine diagnostic of new plumonary infiltrate remain to be evaluated.Microbiological methods used to confirm the diagnostic can be heterogeneous. The development of molecular diagnostic tools may improve the adequacy of antimicrobial therapies of ventilated patients with pneumonia, but we need to further assess its impact in non-ventilated pneumonia.In this review we introduce distinction between hospital-acquired pneumonia according to the localization in the hospital and the oxygenation/ventilation mode. A clarification of definition is the first step to develop more accurate diagnostic strategies and to improve the patients' prognosis.

Device-Associated Hospital-Acquired Infections: Does Active Surveillance With Bundle Care Offer a Pathway to Minimize Them?

Background and objective

The prevalence of hospital-acquired infections (HAIs) is underreported in developing nations due to a lack of systematic active surveillance. This study reports the burden of device-associated HAIs (DA-HAIs) based on two years of active surveillance with in situ bundle care in closed intensive care units (ICUs) of a tertiary care hospital.

Materials and methods

A prospective surveillance study was carried out in 140-bedded ICUs (2,100-bed hospital) of a tertiary care private medical college hospital. Daily active surveillance for catheter-associated urinary tract infection (CAUTI), ventilator-associated event (VAE), and central line-associated bloodstream infection (CLABSI) was done by trained infection control nurses (ICNs) along with quality champion nurses with HAI surveillance forms with bundle care auditing, which was attached to the case sheets of all patients on devices. The surveillance definitions of DA-HAIs were adapted from the Centers for Disease Control and Prevention (CDC)’s National Healthcare Safety Network (CDC-NHSN) 2017 surveillance criteria. Data were analyzed at the end of every month to generate the cumulative device-associated infection (DAI) rates and device utilization ratio (DUR). These data were compared with NHSN and International Nosocomial Infection Control Consortium (INICC) - India HAI rates and communicated to corresponding ICUs and also presented at the hospital infection control committee (HICC) meeting.

Results

The surveillance data were reported over 71,877 patient days during the study period. The DUR of urinary catheters, ventilator, and central line were 0.53, 0.16, and 0.22, respectively. CAUTI, VAE, and CLABSI rates were 0.97, 10.5, and 0.43 per 1,000 device days, respectively. Among 166 DA-HAIs reported, 182 pathogens were identified. Klebsiella pneumoniae was the most common organism isolated, accounting for 37.4% of all DA-HAI cases, followed by Acinetobacter baumanii (30.8%). Most of the Gram-negative organisms were carbapenem-resistant (153/175; 87.4%). Vancomycin resistance rate in Enterococcus was 28.5% (2/7).

Conclusion

DUR and CAUTI, VAE, CLABSI rates were less/on par with the benchmarks of INICC and CDC-NHSN in almost all ICUs of our tertiary care unit. Gram-negative pathogen with 87.4% carbapenem resistance worsened the scenario. Proper active surveillance with bundle care and training by ICNs made a significant difference in all DA-HAI rates, especially VAE, which decreased to 10.5 from 23.6 per 1,000 ventilator days. Sustained active surveillance of HAI and bundle care auditing by a trained infection prevention team with a stringent antibiotic policy are the need of the hour to combat DAIs.

Ventilator-Associated Events: Epidemiology, Risk Factors, and Prevention

The Centers for Disease Control and Prevention shifted the focus of safety surveillance in mechanically ventilated patients from ventilator-associated pneumonia to ventilator-associated events in 2013 to increase the objectivity and reproducibility of surveillance and to encourage quality improvement programs to focus on preventing a broader array of complications. Ventilator-associated events are associated with a doubling of the risk of dying. Prospective studies have found that minimizing sedation, increasing spontaneous awakening and breathing trials, and conservative fluid management can decrease event rates and the duration of ventilation. Multifaceted interventions to enhance these practices can decrease ventilator-associated event rates.

Healthcare professional views on barriers to implementation of evidence-based practice in prevention of ventilator-associated events: A qualitative descriptive study

OBJECTIVE

To explore health professional views of barriers to the use of evidence-based practice to prevent ventilator-associated events in intensive care units.

DESIGN

A qualitative descriptive study was conducted with nurses and doctors with more than six months experience caring for mechanically ventilated patients.

SETTING

The study was conducted in two intensive care units, in large metropolitan health services in Victoria, Australia.

METHODS

Individual semi-structured interviews were undertaken with 20 participants (16 nurses and 4 doctors) in 2019. Purposive sampling method was used until data saturation was reached. The interviews were held at the hospital in a private room away from their place of employment. The interview data were analysed using thematic analysis.

FINDINGS

Four major themes were inductively identified from nine subthemes: i) prioritising specific situations, ii) inadequate use of evidence to underpin practice, iii) perception of inadequate staffing and equipment and, iv) inadequate training and knowledge of evidence-based guidelines.

CONCLUSIONS

These themes helped to explain previously reported deficits in nurses' knowledge of and adherence to evidence-based practice in intensive care. Findings suggest the need for a well-established policy to underpin practice. The barriers faced by nurses and doctors in preventing ventilator associated events need to be addressed to optimise quality of patient care in intensive care units.

A functional polymorphism at the miR‑491‑5p binding site in the 3'‑untranslated region of the MMP‑9 gene increases the risk of developing ventilator‑associated pneumonia

Matrix metalloproteinase (MMP)‑9 is associated with the severity of ventilator‑associated pneumonia (VAP), while an rs1056629 SNP located in the 3'‑untranslated region (UTR) of MMP‑9 affects the microRNA (miRNA/miR)‑491‑mediated regulation of MMP‑9 expression. In the present study, the effect of rs1056629 on the development of VAP in patients with chronic obstructive pulmonary disease (COPD) was investigated. Patients with COPD were enrolled in the study and their genotypes of rs1056629 (CC, CA or AA) were determined. ELISA was used to analyze the levels of TNF‑α and IL‑6 in the monocytes of patients with COPD carrying differential genotypes of rs1056629. Reverse transcription‑quantitative PCR was carried out to evaluate the expression of miR‑491 and MMP‑9 mRNA in the different groups of patients with COPD. Luciferase assay was used to confirm the inhibitory role of miR‑491 in MMP‑9 expression. Western blot analysis was carried out to assess the expression of MMP‑9 protein in A549 and H1299 cells transfected with miR‑491 mimics. The risk and severity of VAP were significantly elevated in patients with COPD carrying the CC and AC genotypes of rs1056629. Although there was no difference in the expression of miR‑491 in patients carrying different genotypes of rs1056629, the expression levels of TNF‑α, IL‑6 and MMP‑9 were increased in patients with COPD carrying the CC and AC genotypes of rs1056629. The results of luciferase assay revealed that miR‑491 inhibited the expression of MMP‑9 through direct binding to the 3'UTR of MMP‑9. Transfection of miR‑491 mimics into A549 and H1299 cells markedly suppressed the expression of MMP‑9 in a concentration‑dependent manner. On the whole, the findings of the present study confirm that the CC and AC genotypes of rs1056629 increase the risk of developing VAP in patients with COPD by increasing the expression of MMP‑9.

Diagnostic and prognostic prediction models in ventilator-associated pneumonia: Systematic review and meta-analysis of prediction modelling studies

PURPOSE

Existing expert systems have not improved the diagnostic accuracy of ventilator-associated pneumonia (VAP). The aim of this systematic literature review was to review and summarize state-of-the-art prediction models detecting or predicting VAP from exhaled breath, patient reports and demographic and clinical characteristics.

METHODS

Both diagnostic and prognostic prediction models were searched from a representative list of multidisciplinary databases. An extensive list of validated search terms was added to the search to cover papers failing to mention predictive research in their title or abstract. Two authors independently selected studies, while three authors extracted data using predefined criteria and data extraction forms. The Prediction Model Risk of Bias Assessment Tool was used to assess both the risk of bias and the applicability of the prediction modelling studies. Technology readiness was also assessed.

RESULTS

Out of 2052 identified studies, 20 were included. Fourteen (70%) studies reported the predictive performance of diagnostic models to detect VAP from exhaled human breath with a high degree of sensitivity and a moderate specificity. In addition, the majority of them were validated on a realistic dataset. The rest of the studies reported the predictive performance of diagnostic and prognostic prediction models to detect VAP from unstructured narratives [2 (10%)] as well as baseline demographics and clinical characteristics [4 (20%)]. All studies, however, had either a high or unclear risk of bias without significant improvements in applicability.

CONCLUSIONS

The development and deployment of prediction modelling studies are limited in VAP and related outcomes. More computational, translational, and clinical research is needed to bring these tools from the bench to the bedside.

REGISTRATION

PROSPERO CRD42020180218, registered on 05-07-2020.

Diagnostic accuracy of electronic surveillance tool for catheter-associated urinary tract infections in tertiary care hospitals: A meta-analysis

BACKGROUND

Automated systems have been developed to reduce labor-intensive manual recordings during nosocomial infection surveillance. The diagnostic accuracies of these systems have differed in various settings.

METHODS

We designed this meta-analysis to evaluate the diagnostic accuracy of an electronic surveillance tool for catheter-associated urinary tract infections (CAUTIs) in tertiary care hospitals. We systematically searched databases such as Medline, Scopus, Cochrane library and Embase (from inception until November 2019) for relevant studies. We assessed the quality of trials using the diagnostic accuracy studies-2 tool, and performed a meta-analysis to obtain a pooled sensitivity and specificity for electronic surveillance. We included 6 studies with 16,492 patients in the analysis.

RESULTS

We found a pooled sensitivity of electronic diagnostic surveillance for CAUTIs of 97.5% (95% confidence interval [CI], 67.6-99.9%) and a pooled specificity of 92.6% (95% CI, 55.2-99.2%). The diagnostic odds ratio was 494 (95% CI, 89-2747). The positive likelihood ratio was 13.1 (95% CI, 1.63-105.8) and the negative likelihood ratio 0.02 (95% CI, 0.001-0.40). A bivariate box plot indicated the possibility of heterogeneity between the included studies.

CONCLUSION

Our review suggests that electronic surveillance is useful for diagnosing CAUTIs among hospitalized patients in tertiary care hospitals due to its high sensitivity and specificity.

Subglottic suction frequency and adverse ventilator-associated events during critical illness

OBJECTIVE

Tracheal intubation and mechanical ventilation provide essential support for patients with respiratory failure, but the course of mechanical ventilation may be complicated by adverse ventilator-associated events (VAEs), which may or may not be associated with infection. We sought to understand how the frequency of subglottic suction, an indicator of the quantity of sputum produced by ventilated patients, relates to the onset of all VAEs and infection-associated VAEs.

DESIGN

We performed a case-crossover study including 87 patients with VAEs, and we evaluated 848 days in the pre-VAE period at risk for a VAE.

SETTING AND PARTICIPANTS

Critically ill patients were recruited from the medical intensive care unit of an academic medical center.

METHODS

We used the number of as-needed subglottic suctioning events performed per calendar day to quantify sputum production, and we compared the immediate pre-VAE period to the preceding period. We used CDC surveillance definitions for VAE and to categorize whether events were infection associated or not.

RESULTS

Sputum quantity measured by subglottic suction frequency is greater in the period immediately prior to VAE than in the preceding period. However, it does not discriminate well between infection-associated VAEs and VAEs without associated infection.

CONCLUSIONS

Subglottic suction frequency may serve as a valuable marker of sputum quantity, and it is associated with risk of a VAE. However, our results require validation in a broader population of mechanically ventilated patients and intensive care settings.

Short-Acting Sedative-Analgesic Drugs Protect Against Development of Ventilator-Associated Events in Children: Secondary Analysis of the EUVAE Study

BACKGROUND

The U.S. Centers for Disease Control and Prevention proposed a shift in its surveillance paradigm from ventilator-associated pneumonia to ventilator-associated events (VAE) to broaden the focus of prevention and achieve a greater impact on outcomes. The main objective of the present study was to identify factors associated with pediatric VAEs in children undergoing mechanical ventilation ≥ 48 h.

METHODS

This was a secondary analysis of a pediatric cohort of a multicenter prospective study. Children who underwent mechanical ventilation ≥ 48 h were included. Exclusion criteria were previous ventilation, extracorporeal life support, and right-to-left shunt or pulmonary hypertension. In the subjects with multiple episodes of mechanical ventilation, only the first episode was considered. Remifentanil and propofol are classified as short-acting sedative and analgesic agents. Pediatric VAE is defined as an "increase in PEEP ≥ 2 cm of H₂O, an increase in [Formula: see text] of 0.20, or an increase in [Formula: see text] of 0.15 plus an increase in PEEP ≥ 1 cm of H₂O sustained for ≥1 d. Associations with pediatric VAE were estimated through multivariate Cox proportional hazards analysis. Hazard ratios and 95% CI were computed.

RESULTS

In a cohort of 90 children, 24 pediatric VAEs were documented in 906 ventilator-days. Pediatric VAEs developed after a median of 4.5 (interquartile range, 4-7.25) d. Surgical admissions, spontaneous breathing trials, early mobility, vasopressors, red blood cell units transfusion, type of sedation (continuous vs intermittent), benzodiazepine use for >3 d, and pharmacologic paralysis were not associated with pediatric VAE, whereas the use of continuous short-acting sedative-analgesic agents was identified as a strong protective factor against pediatric VAE (hazard ratio 0.06 [95% CI 0.007-0.5]).

CONCLUSIONS

Treatment with short-acting sedative-analgesic agents should be preferred for sedation of mechanically ventilated children in intensive care.

The epidemiology and clinical outcomes of ventilator-associated events among 20,769 mechanically ventilated patients at intensive care units: an observational study

Background

Ventilator-associated pneumonia (VAP) is the most common hospital-acquired infection (HAI) in intensive care units (ICUs). Ventilator-associated event (VAE), a more objective definition, has replaced traditional VAP surveillance and is now widely used in the USA. However, the adoption outside the USA is limited. This study aims to describe the epidemiology and clinical outcomes of VAEs in China, based on a prospectively maintained registry.

Methods

An observational study was conducted using an ICU-HAI registry in west China. Patients that were admitted to ICUs and underwent mechanical ventilation (MV) between April 1, 2015, and December 31, 2018, were included. The characteristics and outcomes were compared between patients with and without VAEs. The rates of all VAEs dependent on different ICUs were calculated, and the pathogen distribution of patients with possible VAP (PVAP) was described.

Results

A total of 20,769 ICU patients received MV, accounting for 21,723 episodes of mechanical ventilators and 112,697 ventilator-days. In all, we identified 1882 episodes of ventilator-associated condition (VAC) events (16.7 per 1000 ventilator-days), 721 episodes of infection-related ventilator-associated complications (IVAC) events (6.4 per 1000 ventilator-days), and 185 episodes of PVAP events (1.64 per 1000 ventilator-days). The rates of VAC varied across ICUs with the highest incidence in surgical ICUs (23.72 per 1000 ventilator-days). The median time from the start of ventilation to the onset of the first VAC, IVAC, and PVAP was 5 (3–8), 5 (3–9), and 6 (4–13) days, respectively. The median length of hospital stays was 28.00 (17.00–43.00), 30.00 (19.00–44.00), and 30.00 (21.00–46.00) days for the three VAE tiers, which were all longer than that of patients without VAEs (16.00 [12.00–23.00]). The hospital mortality among patients with VAEs was more than three times of those with non-VAEs.

Conclusions

VAE was common in ICU patients with ≥ 4 ventilator days. All tiers of VAEs were highly correlated with poor clinical outcomes, including longer ICU and hospital stays and increased risk of mortality. These findings highlight the importance of VAE surveillance and the development of new strategies to prevent VAEs.

Usefulness of Sepsis-3 in diagnosing and predicting mortality of ventilator-associated lower respiratory tract infections

BACKGROUND

Early distinguishing ventilator-associated tracheobronchitis (VAT) and ventilator-associated pneumonia (VAP) remains difficult in the daily practice. However, this question appears clinically relevant, as treatments of VAT and VAP currently differ. In this study, we assessed the accuracy of sepsis criteria according to the Sepsis-3 definition in the early distinction between VAT and VAP.

METHODS

Retrospective single-center cohort, including all consecutive patients with a diagnosis of VAT (n = 70) or VAP (n = 136), during a 2-year period. Accuracy of sepsis criteria according to Sepsis-3, total SOFA and respiratory SOFA, calculated at time of microbiological sampling were assessed in differentiating VAT from VAP, and in predicting mortality on ICU discharge.

RESULTS

Sensitivity and specificity of sepsis criteria were found respectively at 0.4 and 0.91 to distinguish VAT from VAP, and at 0.38 and 0.75 for the prediction of mortality in VA-LRTI. A total SOFA ≥ 6 and a respiratory SOFA ≥ 3 were identified as the best cut-offs for these criteria in differentiating VAT from VAP, with sensitivity and specificity respectively found at 0.63 and 0.69 for total SOFA, and at 0.49 and 0.7 for respiratory SOFA. Additionally, for prediction of mortality, a total SOFA ≥ 7 and a respiratory SOFA = 4 were identified as the best-cut-offs, respectively yielding sensitivity and specificity at 0.56 and 0.61 for total SOFA, and at 0.22 and 0.95 for respiratory SOFA.

CONCLUSIONS

Sepsis criteria according to the Sepsis-3 definition show a high specificity but a low sensitivity for the diagnosis of VAP. Our results do not support the use of these criteria for the early diagnosis of VAP in patients with VA-LRTI.

Development of a vaccine against Staphylococcus aureus invasive infections: Evidence based on human immunity, genetics and bacterial evasion mechanisms

Invasive Staphylococcus aureus infections are a leading cause of morbidity and mortality in both hospital and community settings, especially with the widespread emergence of virulent and multi-drug resistant methicillin-resistant S. aureus strains. There is an urgent and unmet clinical need for non-antibiotic immune-based approaches to treat these infections as the increasing antibiotic resistance is creating a serious threat to public health. However, all vaccination attempts aimed at preventing S. aureus invasive infections have failed in human trials, especially all vaccines aimed at generating high titers of opsonic antibodies against S. aureus surface antigens to facilitate antibody-mediated bacterial clearance. In this review, we summarize the data from humans regarding the immune responses that protect against invasive S. aureus infections as well as host genetic factors and bacterial evasion mechanisms, which are important to consider for the future development of effective and successful vaccines and immunotherapies against invasive S. aureus infections in humans. The evidence presented form the basis for a hypothesis that staphylococcal toxins (including superantigens and pore-forming toxins) are important virulence factors, and targeting the neutralization of these toxins are more likely to provide a therapeutic benefit in contrast to prior vaccine attempts to generate antibodies to facilitate opsonophagocytosis.

Ventilator-associated events, not ventilator-associated pneumonia, is associated with higher mortality in trauma patients

BACKGROUND

Ventilator-associated events (VAE), using objective diagnostic criteria, are the preferred quality indicator for patients requiring mechanical ventilation (MV) for greater than 48 hours. We aim to identify the occurrence of VAE in our trauma population, the impact on survival, and length of stay, as compared to the traditional definition of ventilator-associated pneumonia (VAP).

METHODS

This retrospective review included adult trauma patients, who were Washington residents, admitted between 2012 and 2017, and required at least 3 days of MV. Exclusions included patients with Abbreviated Injury Scale head score greater than 4 and burn related mechanisms of injury. We matched trauma registry data with our institutional, physician-adjudicated, and culture-confirmed ventilator event database. We compared the clinical outcomes of ventilator-free days, intensive care unit length of stay, hospital length of stay, and likelihood of death between VAE and VAP.

RESULTS

One thousand five hundred thirty-three trauma patients met criteria; 124 (8.1%) patients developed VAE, 114 (7.4%) patients developed VAP, and 63 (4.1%) patients met criteria for both VAE and VAP. After adjusted analyses, patients with VAE were more likely to die (hazard ratio [HR], 2.86; 95% confidence interval [CI], 1.44-5.68), than those with VAP, as well those patients with neither diagnosis (HR, 2.83; 95% CI, 1.83-4.38). Patients with VAP were no more likely to die (HR, 1.55; 95% CI, 0.91-2.68) than those with neither diagnosis. Patients with VAE had fewer ventilator-free days than those with VAP (HR, -2.71; 95% CI, -4.74 to -0.68).

CONCLUSION

Critically injured trauma patients who develop VAE are three times more likely to die and utilize almost 3 days more MV than those that develop VAP. The objective criteria of VAE make it a promising indicator on which quality indicator efforts should be focused. Future studies should be aimed at identification of modifiable risk factors for VAE and their impact on outcome, as these patients are at high risk for death.

LEVEL OF EVIDENCE

Retrospective cohort study, level III.

Accuracy of ventilator-associated events for the diagnosis of ventilator-associated lower respiratory tract infections

Background

The aim of this study was to investigate the concordance between ventilator-associated events (VAE) and ventilator-associated lower respiratory tract infections (VA-LRTI), and their impact on outcome.

Methods

This retrospective study was performed in five 10-bed ICUs of a teaching hospital, during a 2-year period. Ventilator-associated lower respiratory tract infections (VA-LRTI), including ventilator-associated tracheobronchitis (VAT) and ventilator-associated pneumonia (VAP) were prospectively diagnosed. The agreement between VAE, VAT and VAP was assessed by k statistics.

Results

A total of 1059 patients (15,029 ventilator-days) were included. 268 VAP (17.8 per 1000 ventilator-days), 127 VAT (8.5 per 1000 ventilator-days) and 262 VAE (17.4 per 1000 ventilator-days) were diagnosed. There was no agreement between VAT and VAE, and the agreement was poor between VAP and VAE (k = 0.12, 95% CI 0.03–0.20). VAE and VA-LRTI were associated with significantly longer duration of mechanical ventilation, ICU and hospital length of stay. VAP, VAT and VAE were not significantly associated with mortality in multivariate analysis.

Conclusions

The agreement was poor between VAE and VAP. No agreement was found between VAE and VAT. VAE episodes were significantly associated with longer duration of mechanical ventilation and length of stay, but not with ICU mortality.

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

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

Ventilator-associated events versus ventilator-associated respiratory infections-moving into a new paradigm or merging both concepts, instead?

Despite ventilator-associated respiratory infections (VARI) are reported as the most common and fatal complications related to mechanical ventilation (MV), they are not the unique occurrences. The new classification of ventilator-associated events (VAE) proposed by the centers for disease control and prevention (CDC) enhance the spectra of complications due to MV including both infection-related and non-infectious events. Both VAEs and VARIs are associated with prolonged duration of MV, longer stay in hospital and in the intensive care unit (ICU) and more antibiotic consumption, nonetheless patients with VAEs have worst outcomes. The VARI and VAE algorithms are focused on different targets and the correlation between both classifications is shown to be poor. The diagnostic criteria of the traditional classification have limited accuracy and the non-infectious complications may be misinterpreted as VARI. While the VAE surveillance enhances the spectra of MV complications but excludes less severe VARIs. Noninfective events explain up to 30% of VAEs, the main causes being atelectasis, acute respiratory distress syndrome, pulmonary edema and pulmonary embolism. The bundles assessing VAE are associated with less incidence of VAP and improved outcomes but they fail to reduce the rates of VAE. Automated VAE surveillance is efficient and useful as a quality indicator in the ICU while the differences in the interpretation of VARI criteria limit its role in the design of global protocols and preventive strategies. We suggest that a more comprehensive strategy should combine both algorithms with emphasis on clinical outcomes.

Assessing predictive accuracy for outcomes of ventilator-associated events in an international cohort: the EUVAE study

Purpose

To analyze the impact on patient outcome of ventilator-associated events (VAEs) as defined by the Centers for Disease Control and Prevention (CDC) in 2008, 2013, and the correlation with ventilator-associated pneumonia (VAP) or tracheobronchitis (VAT).

Methods

This was a prospective, observational, multicenter, international study conducted at 13 intensive care units (ICUs); thirty consecutive adults mechanically ventilated for ≥ 48 h per site were eligible, with daily follow-up being recorded in a collaborative web database; VAEs were assessed using the 2013 CDC classification and its 2015 update.

Results

A total of 2856 ventilator days in 244 patients were analyzed, identifying 33 VAP and 51 VAT episodes; 30-day ICU mortality was significantly higher (42.8 vs. 19.6%, p < 0.007) in patients with VAP than in those with VAT. According to the 2013 CDC definitions, 117 VAEs were identified: 113 (96%) were infection-related ventilator-associated complication-plus (IVAC-plus), while possible ventilator-associated pneumonia (PVAP) was found in 64 (56.6%) of them. VAE increased the number of ventilator days and prolonged ICU and hospital LOS (by 5, 11, and 12 days, respectively), with a trend towards increased 30-day mortality (43 vs 28%, p = 0.06). Most episodes (26, 55%) classified as IVAC-plus without PVAP criteria were due to atelectasis. PVAP significantly increased (p < 0.05) ventilator days as well as ICU and hospital LOS (by 10.5, 14, and 13 days, respectively). Only 24 (72.7%) of VAP and 15 (29.4%) of VAT episodes met IVAC-plus criteria.

Conclusions

Respiratory infections (mainly VAT) were the most common complication. VAE algorithms only identified events with surrogates of severe oxygenation deterioration. As a consequence, IVAC definitions missed one fourth of the episodes of VAP and three fourths of the episodes of VAT. Identifying VAT (often missed by IVAC-plus criteria) is important, as VAP and VAT have different impacts on mortality.

Electronic supplementary material

The online version of this article (10.1007/s00134-018-5269-7) contains supplementary material, which is available to authorized users.

Changing panorama for surveillance of device-associated healthcare infections: Challenges faced in implementation of current guidelines

Healthcare-associated infections (HAI) are preventable in up to 30% of patients with evidence-based infection prevention and control (IPC) activities. IPC activities require effective surveillance to generate data for the HAI rates, defining priority areas, identifying processes amenable for improvement and institute interventions to improve patient's safety. However, uniform, accurate and standardised surveillance methodology using objective definitions can only generate meaningful data for effective execution of IPC activities. The highly exhaustive, complex and ever-evolving infection surveillance methodology pose a challenge for effective data capture, analysis and interpretation by ground level personnel. The present review addresses the gaps in knowledge and day-to-day challenges in surveillance faced by infection control team for effective implementation of IPC activities.

Infection-related ventilator-associated complications in ICU patients colonised with extended-spectrum β-lactamase-producing Enterobacteriaceae

PURPOSE

To investigate the clinical significance of infection-related ventilator-associated complications (IVAC) and their impact on carbapenem consumption in mechanically ventilated (MV) patients colonised with extended-spectrum β-lactamase-producing Enterobacteriaceae (ESBLE).

METHODS

Inception cohort study from the French prospective multicenter OUTCOMEREA database (17 ICUs, 1997-2015) including all ESBLE carriers (systematic rectal swabbing at admission then weekly and/or urinary or superficial surgical site colonisation) with MV duration > 48 h and ≥ 1 episode of IVAC after carriage documentation. All ICU-acquired infections were microbiologically documented.

RESULTS

The 318 enrolled ESBLE carriers (median age 68 years; males 67%; medical admission 68%; imported carriage 53%) experienced a total of 576 IVAC comprising 361 episodes (63%) without documented infection, 124 (21%) related to infections other than ventilator-associated pneumonia (VAP), 73 (13%) related to non-ESBLE VAP and 18 (3%) related to ESBLE VAP. Overall, ESBLE infections accounted for only 43 episodes (7%). Carbapenem exposure within the preceding 3 days was the sole independent predictor of ESBLE infection as the causative event of IVAC, with a protective effect (adjusted odds ratio 0.2, 95% confidence interval 0.05-0.6; P < 0.01). Carbapenems were initiated in 9% of IVAC without infection, 15% of IVAC related to non-VAP infections, 42% of IVAC related to non-ESBLE VAP, and 56% of IVAC related to ESBLE VAP (ESBLE VAP versus non-ESBLE VAP: P = 0.43).

CONCLUSIONS

IVAC in ESBLE carriers mostly reflect noninfectious events but act as a strong driver of empirical carbapenem consumption. ESBLE infections are scarce yet hard to predict, strengthening the need for novel diagnostic approaches and carbapenem-sparing alternatives.

Prospective surveillance of device-associated health care-associated infection in an intensive care unit of a tertiary care hospital in New Delhi, India

BACKGROUND

Surveillance of health care-associated infections (HAIs) plays a key role in the hospital infection control program and reduction of HAIs. In India, most of the surveillance of HAIs is reported from private sector hospitals that do not depict the situation of government sector hospitals. Other studies do not confirm with the Centers for Disease Control and Prevention's (CDC) National Healthcare Safety Network (NHSN) surveillance criterion, or deal with ventilator-associated pneumonia (VAP) instead of ventilator-associated event (VAE). The aim of this study was to identify the incidences of 3 device-associated HAIs (DA-HAIs) (VAE, central line-associated bloodstream infection [CLABSI], and catheter-associated urinary tract infection [CAUTI]) by active surveillance using CDC's NHSN surveillance criteria and to identify the pathogens associated with these DA-HAIs.

METHODS

This was a prospective surveillance study (January 2015-December 2016) conducted in an intensive care unit (ICU) of a large, tertiary care, government hospital situated in Delhi, India. Targeted surveillance was done as per the CDC's NHSN 2016 surveillance criteria.

RESULTS

There were 343 patients admitted to the ICU that were included in the study. The surveillance data was reported over 3,755 patient days. A DA-HAIs attack rate of 20.1 per 100 admissions and incidence of 18.3 per 1,000 patient days was observed. The duration of use for each device for patients with DA-HAIs was significantly longer than for patients without DA-HAIs. The device utilization ratios of central line, ventilator, and urinary catheters were 0.57, 0.85, and 0.72, respectively. The crude excess length of stay for patients with DA-HAI was 13 days, and crude excess mortality rate was 11.8%. VAE, CLABSI, and CAUTI rates were 11.8, 7.4, and 9.7 per 1,000 device days, respectively. Among 69 DA-HAIs reported, pathogens could be identified for 49 DA-HAI cases. Klebsiella spp was the most common organism isolated, accounting 28.5% for all DA-HAI cases, followed by Enterococcus spp (24.4%). The most common organisms causing VAE, CAUTI, and CLABSI were Acinetobacter (6/15, 40%), Enterococcus spp (11/31, 35.4%), and Candida spp (5/19, 26.3%), respectively. Most of the gram-negative organisms were carbapenem resistant; however, none of the isolates were colistin resistant.

CONCLUSIONS

To reduce the risk of infection in hospitalized patients, DA-HAI surveillance is of primary importance because it effectively describes and addresses the importance and characteristics of the threatening situation created by DA-HAIs. The present surveillance shows high rates of ICU-onset DA-HAIs and high resistance patterns of organisms causing HAIs, representing a major risk to patient safety.