The clinical impact and preventability of ventilator-associated conditions in critically ill patients who are mechanically ventilated

Chlorhexidine is not effective at any concentration in preventing ventilator-associated pneumonia: a systematic review and network meta-analysis

INTRODUCTION

Oral chlorhexidine has been widely used for ventilator-associated pneumonia prevention in the critical care setting; however, previous studies and evidence synthesis have generated inconsistent findings. Our study aims to investigate if different concentrations of oral chlorhexidine may be effective in preventing such complication in intensive care unit patients.

METHODS

After pre-registration (Open Science Framework: 8CUKF), we conducted a network meta-analysis with the following PICOS: adult patients (age > 18 years old) undergoing invasive mechanical ventilation admitted in ICU (P); any concentration of chlorhexidine used for oral hygiene (I); placebo, sham intervention, usual care, or no intervention (C); rate of VAP (primary outcome), mechanical ventilation length, ICU length of stay (LOS), hospital LOS, mortality (secondary outcomes) (O); randomized controlled trials (S). We used the following database: PubMed, the Cochrane Central Register of Controlled Trials (CENTRAL), Scopus, and EMBASE without any limitation in publication date or language.

RESULTS

Chlorhexidine did not demonstrate any significant advantage over the control group in preventing ventilator-associated pneumonia or reducing mortality, duration of mechanical ventilation, length of stay in the intensive care unit, or overall mortality.

CONCLUSIONS

Chlorhexidine oral decontamination does not reduce the rate of ventilator-associated pneumonia in critically ill adult patients and its routine use could not be recommended.

TRIAL REGISTRATION

Registration number: Open Science Framework: 8CUKF.

Effect of fourth hourly oropharyngeal suctioning on ventilator-associated events in patients requiring mechanical ventilation in intensive care units of a tertiary care center in South India: a randomized controlled trial

BACKGROUND

Mechanical ventilation (MV) is a necessary life-saving measure for critically ill patients. Ventilator-associated events (VAEs) are potentially avoidable complications associated with MV that can double the rate of death. Oral care and oropharyngeal suctioning, although neglected procedures, play a vital role in the prevention of VAE.

METHODS

A randomized controlled trial was conducted in the intensive care units to compare the effect of fourth hourly oropharyngeal suctioning with the standard oral care protocol on VAE among patients on MV. One hundred twenty mechanically ventilated patients who were freshly intubated and expected to be on ventilator support for the next 72 hours were randomly allocated to the control or intervention groups. The intervention was fourth hourly oropharyngeal suctioning along with the standard oral care procedure. The control group received standard oral care (i.e., thrice a day) and on-demand oral suctioning. On the 3rd and 7th days following the intervention, endotracheal aspirates were sent to rule out ventilator-associated pneumonia.

RESULTS

Both groups were homogenous at baseline with respect to their clinical characteristics. The intervention group had fewer VAEs (56.7%) than the control group (78.3%) which was significant at P<0.01. A significant reduction in the status of "positive culture" on ET aspirate also been observed following the 3rd day of the intervention (P<0.001).

CONCLUSIONS

One of the most basic preventive strategies is providing oral care. Oropharyngeal suctioning is also an important component of oral care that prevents microaspiration. Hence, fourth-hourly oropharyngeal suctioning with standard oral care significantly reduces the incidence of VAE.

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.

Impact of a national collaborative project to improve the care of mechanically ventilated patients

This prospective quasi-experimental study from the NASAM (National Approach to Standardize and Improve Mechanical Ventilation) collaborative assessed the impact of evidence-based practices including subglottic suctioning, daily assessment for spontaneous awakening trial (SAT), spontaneous breathing trial (SBT), head of bed elevation, and avoidance of neuromuscular blockers unless otherwise indicated. The study outcomes included VAE (primary) and intensive care unit (ICU) mortality. Changes in daily care process measures and outcomes were evaluated using repeated measures mixed modeling. The results were reported as incident rate ratio (IRR) for each additional month with 95% confidence interval (CI). A comprehensive program that included education on evidence-based practices for optimal care of mechanically ventilated patients with real-time benchmarking of daily care process measures to drive improvement in forty-two ICUs from 26 hospitals in Saudi Arabia (>27,000 days of observation). Compliance with subglottic suctioning, SAT and SBT increased monthly during the project by 3.5%, 2.1% and 1.9%, respectively (IRR 1.035, 95%CI 1.007-1.064, p = 0.0148; 1.021, 95% CI 1.010-1.032, p = 0.0003; and 1.019, 95%CI 1.009-1.029, p = 0.0001, respectively). The use of neuromuscular blockers decreased monthly by 2.5% (IRR 0.975, 95%CI 0.953-0.998, p = 0.0341). The compliance with head of bed elevation was high at baseline and did not change over time. Based on data for 83153 ventilator days, VAE rate was 15.2/1000 ventilator day (95%CI 12.6-18.1) at baseline and did not change during the project (IRR 1.019, 95%CI 0.985-1.053, p = 0.2812). Based on data for 8523 patients; the mortality was 30.4% (95%CI 27.4-33.6) at baseline, and decreased monthly during the project by 1.6% (IRR 0.984, 95%CI 0.973-0.996, p = 0.0067). A national quality improvement collaborative was associated with improvements in daily care processes. These changes were associated with a reduction in mortality but not VAEs. Registration The study is registered in clinicaltrials.gov (NCT03790150).

Predicting respiratory decompensation in mechanically ventilated adult ICU patients

Introduction: Mechanical ventilation is a life-saving treatment in the Intensive Care Unit (ICU), but often causes patients to be at risk of further respiratory complication. We created a statistical model utilizing electronic health record and physiologic vitals data to predict the Center for Disease Control and Prevention (CDC) defined Ventilator Associated Complications (VACs). Further, we evaluated the effect of data temporal resolution and feature generation method choice on the accuracy of such a constructed model. Methods: We constructed a random forest model to predict occurrence of VACs using health records and chart events from adult patients in the Medical Information Mart for Intensive Care III (MIMIC-III) database. We trained the machine learning models on two patient populations of 1921 and 464 based on low and high frequency data availability. Model features were generated using both basic statistical summaries and tsfresh, a python library that generates a large number of derived time-series features. Classification to determine whether a patient will experience VAC one hour after 35 h of ventilation was performed using a random forest classifier. Two different sample spaces conditioned on five varying feature extraction techniques were evaluated to identify the most optimal selection of features resulting in the best VAC discrimination. Each dataset was assessed using K-folds cross-validation (k = 10), giving average area under the receiver operating characteristic curves (AUROCs) and accuracies. Results: After feature selection, hyperparameter tuning, and feature extraction, the best performing model used automatically generated features on high frequency data and achieved an average AUROC of 0.83 ± 0.11 and an average accuracy of 0.69 ± 0.10. Discussion: Results show the potential viability of predicting VACs using machine learning, and indicate that higher-resolution data and the larger feature set generated by tsfresh yield better AUROCs compared to lower-resolution data and manual statistical features.

Effects of different types and frequencies of early rehabilitation on ventilator weaning among patients in intensive care units: A systematic review and meta-analysis

OBJECTIVE

This study aimed to investigate the effects of different types and frequencies of physiotherapy on ventilator weaning among patients in the intensive care unit (ICU) and to identify the optimal type and frequency of intervention.

DATA SOURCES

PubMed, Cochrane Library, EMBASE, and Airiti Library.

STUDY SELECTION

Randomized controlled trials that provided information on the dosage of ICU rehabilitation and the parameters related to ventilator weaning were included.

DATA EXTRACTION AND MANAGEMENT

Treatment types were classified into conventional physical therapy, exercise-based physical therapy, neuromuscular electrical stimulation (NEMS), progressive mobility, and multi-component. The frequencies were divided into high (≥ 2 sessions/day or NEMS of > 60 minutes/day), moderate (one session/day, 3-7 days/week or NEMS of 30-60 minutes/day), and low (one session/day, < 3 days/week, or NEMS of < 30 minutes/day).

DATA SYNTHESIS

Twenty-four articles were included for systematic review and 15 out of 24 articles were analyzed in the meta-analysis. Early rehabilitation, especially the progressive mobility treatment exerted an optimal effect in reducing the ventilator duration in patients in the ICU (standardized mean difference [SMD] = 0.91; 95% confidence interval [CI] = 0.23-1.58; P < 0.01). Regarding the treatment frequency, the high-frequency intervention did not result in a favorable effect on ventilator duration compared with the moderate frequency of treatment (SMD = 0.75; 95% CI = -1.13-2.64; P = 0.43).

CONCLUSION

Early rehabilitation with progressive mobility is highly recommended to decrease the ventilation duration received by patients in the ICU. Depending on clinical resources and the tolerance of patients, the frequency of interventions should reach moderate-to-high frequency, that is, at least one session per day and 3 days a week.

TRIAL REGISTRATION

Registration number: PROSPERO (CRD42021243331).

Predicting mortality in moderate-severe TBI patients without early withdrawal of life-sustaining treatments including ICU complications: The MYSTIC-score

PURPOSE

To develop and internally validate the MortalitY in Moderate-Severe TBI plus ICU Complications (MYSTIC)-Score to predict in-hospital mortality of msTBI patients without early (<24 h) withdrawal-of-life-sustaining treatments.

METHODS

We analyzed data from a Neuro-Trauma Intensive Care Unit prospectively collected between 11/2009-5/2019. Consecutive adult msTBI patients were included if Glasgow Coma Scale≤12, and neither died nor had withdrawal-of-life-sustaining treatments within 24 h of admission (n = 485). Using univariate and multivariable logistic regression in a random-split cohort approach (2/3 derivation;1/3 validation), we identified independent predictors of in-hospital mortality while adjusting for validated predictors of mortality (IMPACT-variables). We constructed the MYSTIC-Score and examined discrimination and calibration.

RESULTS

The MYSTIC-Score included the ICU complications brain edema, herniation, systemic inflammatory response syndrome, sepsis, acute kidney injury, cardiac arrest, and urinary tract infection. In the derivation cohort(n = 324), discrimination and calibration were excellent (area-under-the-receiver-operating-curve [AUC-ROC] = 0.95;Hosmer-Lemeshow p-value = 0.09, with p > 0.05 indicating good calibration). Internal validation revealed an AUC-ROC = 0.93 and Hosmer-Lemeshow-p-value = 0.76 (n = 161).

CONCLUSIONS

Certain ICU complications are independent predictors of in-hospital mortality and strengthen outcome prediction in msTBI when combined with validated admission predictors of mortality. However, external validation is needed to determine robustness and practical applicability of our model given the high potential for residual confounders.

Nanoparticle-modified microrobots for in vivo antibiotic delivery to treat acute bacterial pneumonia

Bioinspired microrobots capable of actively moving in biological fluids have attracted considerable attention for biomedical applications because of their unique dynamic features that are otherwise difficult to achieve by their static counterparts. Here we use click chemistry to attach antibiotic-loaded neutrophil membrane-coated polymeric nanoparticles to natural microalgae, thus creating hybrid microrobots for the active delivery of antibiotics in the lungs in vivo. The microrobots show fast speed (>110 µm s^-1) in simulated lung fluid and uniform distribution into deep lung tissues, low clearance by alveolar macrophages and superb tissue retention time (>2 days) after intratracheal administration to test animals. In a mouse model of acute Pseudomonas aeruginosa pneumonia, the microrobots effectively reduce bacterial burden and substantially lessen animal mortality, with negligible toxicity. Overall, these findings highlight the attractive functions of algae-nanoparticle hybrid microrobots for the active in vivo delivery of therapeutics to the lungs in intensive care unit settings.

Pro-, pre- and synbiotics for the prevention of incidental ventilator-associated pneumonia among critically ill patients: a systematic review and meta-analysis of randomized controlled trials

OBJECTIVES

This study investigated the preventive effects of pro-, pre- and synbiotics on ventilator-associated pneumonia (VAP) among critically ill patients.

METHODS

The PubMed, Web of Science, Ovid MEDLINE, Embase, Cochrane Central Register of Controlled Trials, and ClinicalTrials.gov databases were searched for relevant articles written before 19 February 2022. Only randomized controlled trials (RCTs) comparing the clinical efficacy of pro-, pre- and synbiotics with placebos or standard treatments for the prevention of incidental VAP were included.

RESULTS

A total of 15 RCTs were included. Patients receiving pro-, pre- and synbiotics had a lower risk than the control group of contracting VAP (risk ratio [RR], 0.70; 95% CI, 0.57-0.85; I² = 67%). The duration of mechanical ventilation was significantly shorter in the study group than in the control group (mean difference [MD], -1.61 days; 95% CI, -2.72 to -0.50; I² = 86%), and the study group had a shorter duration of stay in the intensive care unit than the control group did (MD, -1.72 days; 95% CI, -3.22 to -0.23; I² = 87%).

CONCLUSIONS

Pro-, pre- and synbiotics can prevent VAP and the use of probiotics for patients who are critically ill should be supported.

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.

Physical Rehabilitation Programs for Bedridden Patients with Prolonged Immobility: A Scoping Review

Bedridden patients usually stay in bed for long periods, presenting several problems caused by immobility, leading to a long recovery process. Thus, identifying physical rehabilitation programs for bedridden patients with prolonged immobility requires urgent research. Therefore, this scoping review aimed to map existing physical rehabilitation programs for bedridden patients with prolonged immobility, the rehabilitation domains, the devices used, the parameters accessed, and the context in which these programs were performed. This scoping review, guided by the Joanna Briggs Institute’s (JBI) methodology and conducted in different databases (including grey literature), identified 475 articles, of which 27 were included in this review. The observed contexts included research institutes, hospitals, rehabilitation units, nursing homes, long-term units, and palliative care units. Most of the programs were directed to the musculoskeletal domain, predominantly toward the lower limbs. The devices used included lower limb mobilization, electrical stimulation, inclined planes, and cycle ergometers. Most of the evaluated parameters were musculoskeletal, cardiorespiratory, or vital signs. The variability of the programs, domains, devices and parameters found in this scoping review revealed no uniformity, a consequence of the personalization and individualization of care, which makes the development of a standard intervention program challenging.

Clinical Benefits From Administering Probiotics to Mechanical Ventilated Patients in Intensive Care Unit: A PRISMA-Guided Meta-Analysis

Background

The use of probiotics has been considered as a new intervention for ventilator-associated pneumonia (VAP) prevention in the intensive care unit (ICU). The aim of this meta-analysis was to evaluate the effect of probiotics on mechanical-ventilated patients in ICU.

Methods

PubMed, Embase, Scopus, and the Cochrane Library were searched for relevant randomized controlled trials (RCTs) from their respective inception through October 10, 2021. All studies meeting the inclusion criteria were selected to evaluate the effect of probiotics on patients receiving mechanical ventilation in ICU.

Results

A total of 15 studies involving 4,693 participants met our inclusion criterion and were included in this meta-analysis. The incidence of VAP in the probiotic group was significantly lower (odds ratio [OR] 0.58, 95% CI 0.41 to 0.81; p = 0.002; I² = 71%). However, a publication bias may be present as the test of asymmetry was significant (p = 0.007). The probiotic administration was associated with a significant reduction in the duration of mechanical ventilation (mean difference [MD] −1.57, 95% CI −3.12 to −0.03; p = 0.05; inconsistency [I]² = 80%), length of ICU stay (MD −1.87, 95% CI −3.45 to −0.28; p = 0.02; I² = 76%), and incidence of bacterial colonization (OR 0.59, 95% CI 0.45 to 0.78; p = 0.0001; I² = 34%). Moreover, no statistically significant differences were observed regarding the incidence of diarrhea (OR 0.90, 95% CI 0.65 to 1.25; p = 0.54; I² = 12%) and mortality (OR 0.91, 95% CI 0.80 to 1.05; p = 0.19; I² = 0%) between probiotics group and control group.

Conclusion

Our meta-analysis shows that probiotics are associated with a reduction in VAP, as well as the duration of mechanical ventilation, ICU length of stay, and bacterial colonization, but no significant effects on ICU mortality and occurrence of diarrhea. However, in consideration of the significant heterogeneity and publication bias, our findings need to be further validated.

Systematic Review Registration

https://www.crd.york.ac.uk/prospero/, identifier: CRD42020150770.

Incidence, Characteristics, and Outcomes of Ventilator-associated Events during the COVID-19 Pandemic

Rationale: Ventilator-associated event (VAE) surveillance provides an objective means to measure and compare complications that develop during mechanical ventilation by identifying patients with sustained increases in ventilator settings after a period of stable or decreasing ventilator settings. The impact of the coronavirus disease (COVID-19) pandemic on VAE rates and characteristics is unknown. Objectives: To compare the incidence, causes, and outcomes of VAE during the COVID-19 pandemic year versus prepandemic years and among ventilated patients with and without COVID-19. Methods: In this retrospective cohort study of mechanically ventilated adults at four academic and community hospitals in Massachusetts, we compared VAE incidence rates between March 1 and August 31 for each year from 2017 to 2020 (corresponding to the time frame of the pandemic first wave in 2020) and among COVID-19-positive and COVID-19-negative patients in 2020. The medical records of 200 randomly selected patients with VAEs in 2020 (100 with COVID-19 and 100 without COVID-19) were analyzed to compare conditions precipitating VAEs in patients with versus without COVID-19. Results: VAEs per 100 episodes of mechanical ventilation were more common in 2020 than in prior years (11.2 vs. 6.7; P < 0.01) but the rate of VAEs per 1,000 ventilator-days was similar (14.2 vs. 12.7; P = 0.08). VAEs were more frequent in COVID-19-positive patients than in COVID-19-negative patients in 2020 (29.0 vs. 7.1 per 100 ventilator episodes [P < 0.01] and 17.2 vs. 12.2 per 1,000 ventilator-days [P < 0.01]). Compared with patients without COVID-19 with VAEs, patients with COVID-19 and VAEs had similar rates of infection-related ventilator-associated complications, longer median durations of mechanical ventilation (22 vs. 14 d; P < 0.01), and similar in-hospital mortality (30% vs. 38%; P = 0.15). Progressive acute respiratory distress syndrome (ARDS) accounted for 53% of VAEs in patients with COVID-19, whereas it accounted for 14% of VAEs among patients without COVID-19. Conclusions: VAE rates per 100 episodes of mechanical ventilation and per 1,000 ventilator-days were higher among COVID-19-positive patients than among COVID-19-negative patients. Over 50% of VAEs in patients with COVID-19 were caused by progressive ARDS, whereas less than 15% of VAEs in patients without COVID-19 were caused by progressive ARDS. These findings provide insight into the natural history of COVID-19 in ventilated patients and may inform targeted strategies to mitigate complications in this population.

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.

Effect of oral chlorhexidine de-adoption and implementation of an oral care bundle on mortality for mechanically ventilated patients in the intensive care unit (CHORAL): a multi-center stepped wedge cluster-randomized controlled trial

Purpose

Oral chlorhexidine is used widely for mechanically ventilated patients to prevent pneumonia, but recent studies show an association with excess mortality. We examined whether de-adoption of chlorhexidine and parallel implementation of a standardized oral care bundle reduces intensive care unit (ICU) mortality in mechanically ventilated patients.

Methods

A stepped wedge cluster-randomized controlled trial with concurrent process evaluation in 6 ICUs in Toronto, Canada. Clusters were randomized to de-adopt chlorhexidine and implement a standardized oral care bundle at 2-month intervals. The primary outcome was ICU mortality. Secondary outcomes were time to infection-related ventilator-associated complications (IVACs), oral procedural pain and oral health dysfunction. An exploratory post hoc analysis examined time to extubation in survivors.

Results

A total of 3260 patients were enrolled; 1560 control, 1700 intervention. ICU mortality for the intervention and control periods were 399 (23.5%) and 330 (21.2%), respectively (adjusted odds ratio [aOR], 1.13; 95% confidence interval [CI] 0.82 to 1.54; P = 0.46). Time to IVACs (adjusted hazard ratio [aHR], 1.06; 95% CI 0.44 to 2.57; P = 0.90), time to extubation (aHR 1.03; 95% CI 0.85 to 1.23; P = 0.79) (survivors) and oral procedural pain (aOR, 0.62; 95% CI 0.34 to 1.10; P = 0.10) were similar between control and intervention periods. However, oral health dysfunction scores (− 0.96; 95% CI − 1.75 to − 0.17; P = 0.02) improved in the intervention period.

Conclusion

Among mechanically ventilated ICU patients, no benefit was observed for de-adoption of chlorhexidine and implementation of an oral care bundle on ICU mortality, IVACs, oral procedural pain, or time to extubation. The intervention may improve oral health.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00134-021-06475-2.

Validation of rapid shallow breathing index displayed by the ventilator compared to the standard technique in patients with readiness for weaning

BACKGROUND

Rapid shallow breathing index (RSBI) is the most commonly used parameter for predicting weaning outcome. Measurement of RSBI by Wright spirometer (RSBI_standard) is the standard method in routine clinical practice. Data specific to the accuracy and reliability of the RSBI value displayed by the ventilator (RSBI_vent) are scarce. Accordingly, this study aimed to evaluate the association between the average value of RSBI_vent at different time points and RSBI_standard, and to assess the accuracy and reliability of these two RSBI measurement techniques.

METHODS

This prospective cohort study included mechanically ventilated patients who were ready to wean. At the beginning of spontaneous breathing trial using the flow-by method, RSBI was measured by two different techniques at the same time, including: (1) Wright spirometer (breathing frequency/average tidal volume in 1 min) (RSBI_standard), and (2) the values displayed on the ventilator at 0, 15, 30, 45, and 60 s (RSBI_vent).

RESULTS

Forty-seven patients were enrolled. The RSBI_vent value was significantly higher than the RSBI_standard value for every comparison. According to Spearman's correlation coefficient (r) and intraclass correlation coefficient (ICC), the average value of RSBI from 5 time points (0, 15, 30, 45, and 60 s) showed the best correlation with the standard technique (r = 0.76 [P < 0.001], and ICC = 0.79 [95% CI 0.61-0.88], respectively). Bland-Altman plot also showed the best agreement between RSBI_standard and the RSBI_vent value averaged among 5 time points (mean difference - 17.1 breaths/min/L).

CONCLUSIONS

We found that the ventilator significantly overestimates the RSBI value compared to the standard technique by Wright spirometer. The average RSBI_vent value among 5 time points (0, 15, 30, 45, and 60 s) was found to best correlate with RSBI_standard.

Clinical outcomes and risk factors for mortality from ventilator-associated events: A registry-based cohort study among 30,830 intensive care unit patients

OBJECTIVE

To investigate the clinical impact of ventilator-associated events (VAEs) on adverse prognoses and risk factors for mortality among intensive care unit (ICU) patients receiving invasive mechanical ventilation (IMV) based on an ICU healthcare-associated infection (ICU-HAI) registry.

DESIGN

A cohort study was conducted based on an ICU-HAI registry including 30,830 patients between 2015 and 2018.

SETTING

The study was conducted using data from 5 adult ICUs of a referral hospital.

PATIENTS

Adult patients in the ICU-HAI registry who received ≥4 consecutive IMV days.

METHODS

Clinical outcomes and mortality risk factors for VAEs were analyzed using propensity score matching (PSM), multivariate regression models, and sensitivity analyses.

RESULTS

Of 6,426 included patients, 1,803 developed 1,899 VAEs. After PSM, patients with VAEs did have prolonged length of stay in the ICU and in the hospital, increased hospitalization costs, longer days on mechanical ventilation, higher proportion of ≥9 days on mechanical ventilation, higher rate of failure in extubating mechanical ventilation, and excess all-cause mortality in the ICU. Older age (adjusted OR [aOR], 1.02), higher APACHE II score on ICU admission (aOR, 1.06), pneumonia (aOR, 1.49), blood transfusion (aOR 1.43), immunosuppressive drugs (aOR, 1.69), central-line catheter (aOR, 2.06), and ≥2 VAEs in the ICU (aOR, 1.99) were associated with higher risks for all-cause mortality in an ICU.

CONCLUSIONS

Patients with VAEs indeed had poorer clinical outcomes. Older age, higher APACHE II score on ICU admission, pneumonia, blood transfusion, immunosuppressive drugs, central-line catheter, and ≥2 VAEs in the ICU were risk factors for all-cause mortality of VAE patients in the ICU.

Evaluation of ventilator associated events in critically ill patients with invasive mechanical ventilation: A prospective cohort study at a resource limited setting in Northern India

PURPOSE

The primary aim of this study was to identify the modifiable risk factors for acquiring ventilator associated events (VAE). Secondary aims were to investigate the intensive care unit (ICU) course and impact of VAE on patient outcome.

METHODS

This prospective, observational single center cohort study included 247 patients on mechanical ventilation for 4 calendar days at a 20-bed ICU between January 2018-June 2019.

RESULTS

VAE occurred in 59 episodes (rate 11.3 per 1000 ventilator-days). The Ventilator Utilization Ratio (VUR) was 0.57. The median time to onset of VAE was 6 days. Sepsis was the most common reason for initiating patients on invasive mechanical ventilation (IMV). Cumulative fluid balance ≥2 l (Odds Ratio 30.92; 95% CI 9.82-97.37) and greater number of days with vasopressor support (Odds Ratio 1.92; 95% CI 1.57-2.36) within 7 days of initiating IMV were significant risk factors for acquiring VAE (p < 0.001). VAE cases were ventilated for significantly more days (20 vs 14 days, p = 0.001, had longer days of ICU stay (29 vs 18 days; p = 0.002) and higher hospital mortality (p = 0.02). Klebsiella pneumoniae was the most common isolate (N = 28) and 32.1% were colistin resistant.

CONCLUSIONS

Prospective intervention studies are needed to determine if targeting these risk factors can lower VAE rates in our setting.

Additional medical costs associated with ventilator-associated pneumonia in an intensive care unit in Japan

BACKGROUND

Additional health care costs associated with ventilator-associated pneumonia (VAP) vary widely per country; none of which have been explored in Japan. Thus, we aimed to examine the economic and clinical effects of VAP in Japan.

METHODS

This was a retrospective matched case-control study of 22 patients with VAP who were treated in the intensive care unit of Yokohama Rosai Hospital between January 2012 and December 2018. Twenty-two matched controls were selected based on 5 variables (ie, sex, age, diagnosis and surgical procedure, underlying disease with or without advanced malignant tumor, and best motor response). The additional health care costs incurred owing to VAP were calculated from the difference between the mean costs of VAP and control cases.

RESULTS

VAP incurred an additional cost of approximately United States Dollars (USD) 34,884 per case. The length of hospitalization itself was the major factor contributing to additional medical costs, generating a difference of 9,824 USD.

DISCUSSION

VAP not only worsens patient outcomes but also generates significant additional medical costs. Patients who had developed VAP required more medical resources such as the performance of a tracheostomy.

CONCLUSIONS

VAP incurs a higher mean total hospital medical cost. Thus, appropriate infection control strategies should be implemented.

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.

Do probiotics help prevent ventilator-associated pneumonia in critically ill patients? A systematic review with meta-analysis

Background

Probiotic treatments might contribute to the prevention of ventilator-associated pneumonia (VAP). Due to its unclear clinical effects, here we intend to assess the preventive effect and safety of probiotics on intensive care unit (ICU) patients.

Methods

Eligible randomised controlled trials were selected in databases until 30 September 2019. The characteristics of the studies were extracted, including study design, definition of VAP, probiotics intervention, category of included patients, incidence of VAP, mortality, duration of mechanical ventilation (MV) and ICU stay. Heterogeneity was evaluated by Chi-squared and I² tests.

Results

15 studies involving 2039 patients were identified for analysis. The pooled analysis suggests significant reduction on VAP (risk ratio, 0.68; 95% Cl, 0.60 to 0.77; p<0.00001) in a fixed-effects model. Subgroup analyses performed on the category of clinical and microbiological criteria both support the above conclusion; however, there were no significant differences in duration of MV or length of ICU stay in a random-effects model. Also, no significant differences in total mortality, overall mortality, 28-day mortality or 90-day mortality were found in the fixed-effects model.

Conclusions

The probiotics helped to prevent VAP without impacting the duration of MV, length of ICU stay or mortality.

Factors Predictive of Ventilator-associated Pneumonia in Critically Ill Trauma Patients

BACKGROUND

Ventilator-associated pneumonia (VAP) is a serious complication of mechanical ventilation. We sought to investigate factors associated with the development of VAP in critically ill trauma patients.

METHODS

We conducted a retrospective review of trauma patients admitted to our trauma intensive care unit between 2016 and 2018. Patients with ventilator-associated pneumonia were identified from the trauma database. Data collected from the trauma database included demographics (age, gender and race), mechanism of injury (blunt, penetrating), injury severity (injury severity score "ISS"), the presence of VAP, transfused blood products and presenting vital signs.

RESULTS

A total of 1403 patients were admitted to the trauma intensive care unit (TICU) during the study period; of these, 45 had ventilator-associated pneumonia. Patients with VAP were older (p = 0.030), and they had a higher incidence of massive transfusion (p = 0.015) and received more packed cells in the first 24 h of admission (p = 0.028). They had a higher incidence of face injury (p = 0.001), injury to sternum (p = 0.011) and injury to spine (p = 0.024). Patients with VAP also had a higher incidence of acute kidney injury (AKI) (p < 0.001) and had a longer ICU (p < 0.001) and hospital length of stay (p < 0.001). Multiple logistic regression models controlling for age and injury severity (ISS) showed massive transfusion (p = 0.017), AKI (p < 0.001), injury to face (p < 0.001), injury to sternum (p = 0.007), injury to spine (p = 0.047) and ICU length of stay (p < 0.001) to be independent predictors of VAP.

CONCLUSIONS

Among critically ill trauma patients, acute kidney injury, injury to the spine, face or sternum, massive transfusion and intensive care unit length of stay were associated with VAP.

Pulmonary Rehabilitation in COVID-19 patients: A scoping review of current practice and its application during the pandemic

The novel coronavirus-2019 (COVID-19) pandemic primarily affects the respiratory system. Elderly individuals with comorbidity are severely affected. Survivors weaned from mechanical ventilation are at a higher risk of developing post-intensive care syndrome (PICS). This scoping review, based on 40 recent publications, highlights pulmonary rehabilitation (PR) in COVID-19. There is a paucity of high-quality research on this topic. However, rehabilitation societies including the Turkish Society of Physical Medicine and Rehabilitation have issued PR recommendations in COVID-19 pneumonia with productive cough can benefit from diaphragmatic breathing, pursed-lip breathing, and resistance-breathing training. Besides, those in mechanical ventilation and post-PICS COVID-19 cases, oxygen therapy, early mobilization, airway clearance, aerobic exercise, gradual-graded limb muscle resistance exercise, nutritional and psychological interventions should be consideration. During PR, careful evaluation of vital signs and exercise-induced symptoms is also required. When in-person PR is not possible, telerehabilitation should be explored. However, the long-term effects of PR in COVID-19 need further evaluation.

Economic evaluation alongside the Probiotics to Prevent Severe Pneumonia and Endotracheal Colonization Trial (E-PROSPECT): study protocol

INTRODUCTION

Ventilator-associated pneumonia (VAP) is a common healthcare-associated infection in the intensive care unit (ICU). Probiotics are defined as live microorganisms that may confer health benefits when ingested. Prior randomised trials suggest that probiotics may prevent infections such as VAP and Clostridioides difficile-associated diarrhoea (CDAD). PROSPECT (Probiotics to Prevent Severe Pneumonia and Endotracheal Colonization Trial) is a multicentre, double-blinded, randomised controlled trial comparing the efficacy of the probiotic Lactobacillus rhamnosus GG with usual care versus usual care without probiotics in preventing VAP and other clinically important outcomes in critically ill patients admitted to the ICU.

METHODS AND ANALYSIS

The objective of E-PROSPECT is to determine the incremental cost-effectiveness of L. rhamnosus GG plus usual care versus usual care without probiotics in critically ill patients. E-PROSPECT will be performed from the public healthcare payer's perspective over a time horizon from ICU admission to hospital discharge.We will determine probabilities of in-ICU and in-hospital events from all patients alongside PROSPECT. We will retrieve unit costs for each resource use item using jurisdiction-specific public databases, supplemented by individual site unit costs if such databases are unavailable. Direct costs will include medications, personnel costs, radiology/laboratory testing, operative/non-operative procedures and per-day hospital 'hoteling' costs not otherwise encompassed. The primary outcome is the incremental cost per VAP prevented between the two treatment groups. Other clinical events such as CDAD, antibiotic-associated diarrhoea and in-hospital mortality will be included as secondary outcomes. We will perform pre-specified subgroup analyses (medical/surgical/trauma; age; frailty status; antibiotic use; prevalent vs no prevalent pneumonia) and probabilistic sensitivity analyses for VAP, then generate confidence intervals using the non-parametric bootstrapping approach.

ETHICS AND DISSEMINATION

Study approval for E-PROSPECT was granted by the Hamilton Integrated Research Ethics Board of McMaster University on 29 July 2019. Informed consent was obtained from the patient or substitute decision-maker in PROSPECT. The findings of this study will be published in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

NCT01782755; Pre-results.

A Comparison of Outcomes of Trauma Patients With Ventilator-Associated Events by Diagnostic Criteria Set

BACKGROUND

The Centers for Disease Control and Prevention replaced the definition for ventilator-associated pneumonia with an algorithm comprised of three categories: ventilator-associated condition (VAC), infection-related ventilator associated complication (IVAC), and possible ventilator-associated pneumonia (PVAP). We sought to compare the outcome of trauma patients with VAEs to those with no VAEs.

METHODS

Patients admitted from 2013 to 2017 were identified from trauma registry. Logistic regression was performed for the association between VAEs and mortality.

RESULTS

Two thousand six hundred eighty patients were admitted to our trauma center, 2,290 had no VAE, 100 had VACs, 85 had IVACs, and 205 had PVAPs. Adjusted for race, sex, blunt injury mechanisms, and Injury Severity Score, all VAEs had a longer hospital length of stay, intensive care unit stay, and days of ventilator support when compared with those with no VAE (all P < 0.0001). Nosocomial complication rates were not different by VAE group. Compared with patients with no VAE, an over 2-fold increased mortality odds was observed for VAC (OR 2.39, 95% CI 1.50-3.80) and IVAC patients (OR 2.07, 95% CI 1.23-3.47), and a 50% mortality increased was observed for PVAP patients (OR 1.46, 95% CI 1.00-2.12). These associations became similar with an approximate 2.5-fold increased mortality odds among patients with at least 1 week on ventilator support.

CONCLUSION

VAEs increase the odds of mortality, particularly for patients with VACs and IVACs. Among patients on ventilator support for at least a week, the associations are similar among VAE types, suggesting no single VAE type is more severe than others.

Minor change in initial PEEP setting decreases rates of ventilator-associated events in mechanically ventilated trauma patients

Background

Surveillance of ventilator-associated events (VAEs) as defined by the National Healthcare Safety Network (NHSN) is performed at many US trauma centers and considered a measure of healthcare quality. The surveillance algorithm relies in part on increases in positive end-expiratory pressure (PEEP) to identify VAEs. The purpose of this cohort study was to evaluate the effect of initiating mechanically ventilated trauma patients at marginally higher PEEP on incidence of VAEs.

Methods

Analysis of level-1 trauma center patients mechanically ventilated 2+ days from 2017 to 2018 was performed after an institutional ventilation protocol increased initial PEEP setting from 5 (2017) to 6 (2018)cm H₂O. Incidence of VAEs per 1000 vent days was compared between PEEP groups. Logistic regression modelling was performed to evaluate the impact of the PEEP setting change adjusted to account for age, ventilator days, injury mechanism and injury severity.

Results

519 patients met study criteria (274 PEEP 5 and 245 PEEP 6). Rates of VAEs were significantly reduced among patients with initial PEEP 5 versus 6 (14.61 per 1000 vent days vs. 7.13 per 1000 vent days; p=0.039). Logistic regression demonstrated that initial PEEP 6 was associated with 62% reduction in VAEs.

Conclusions

Our data suggest that an incrementally increased baseline PEEP setting was associated with a significantly decreased incidence of VAEs among trauma patients. This minor change in practice may have a major impact on a trauma center’s quality metrics.

Level of evidence

IV.

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.

Implementation of an experiential learning strategy to reduce the risk of ventilator-associated pneumonia in critically ill adult patients

Objective

We evaluated the impact of an experiential learning strategy on both the adherence to the use of bundles and the incidence of ventilator-associated pneumonia in critically ill adult patients.

Methods

Longitudinal, quasi-experimental interrupted time-series study in a tertiary teaching hospital in Buenos Aires, Argentina. Successive measurements were made before and after the intervention was implemented between January 2016 and December 2018. Our main exposure was experiential learning, which was based on a combination of play activities, simulation models, knowledge and attitude competencies, role-playing and feedback. The adherence to the bundle for the care of mechanically ventilated critically-ill adult patients and the occurrence of ventilator-associated pneumonia were the main outcomes of interest. We used generalized linear models including time as a linear spline to estimate the effect of the experiential learning strategy both on the adherence to the bundle of care and the occurrence of ventilator-associated pneumonia during long-term follow-up.

Results

The overall proportion of adequate bundle use before and after the implementation of the intervention was 60.8% (95% CI: 56.9-64.7) and 85.6% (95% CI: 81.2-90.1), respectively. The incidence rate of ventilator-associated pneumonia before and after the intervention was 6.11 (95% CI: 5.82-6.40) and 3.55 (95% CI: 2.96-4.14) every 1000 days of mechanical ventilation, respectively. The estimated baseline monthly change in the adherence to the mechanical ventilation bundle was 0.4% (95%CI: -0.3-1.2%, p = 0.31) and 1.1% (95% CI: 0.2-2.2%, p < 0.01) before and after the implementation of the intervention, respectively. These results were consistent across our statistical quality control analysis.

Conclusions

The implementation of experiential learning strategies improves the adherence to bundles in the care of mechanically ventilated critically ill adult patients. Such strategies also decrease the incidence rate of ventilator-associated pneumonia. Both effects appear to remain constant during long-term follow-up.

Protocol for a multi-centered, stepped wedge, cluster randomized controlled trial of the de-adoption of oral chlorhexidine prophylaxis and implementation of an oral care bundle for mechanically ventilated critically ill patients: the CHORAL study

BACKGROUND

Routine application of chlorhexidine oral rinse is recommended to reduce risk of ventilator-associated pneumonia (VAP) in mechanically ventilated patients. Recent reappraisal of the evidence from two meta-analyses suggests chlorhexidine may cause excess mortality in non-cardiac surgery patients and does not reduce VAP. Mechanisms for possible excess mortality are unclear. The CHORAL study will evaluate the impact of de-adopting chlorhexidine and implementing an oral care bundle (excluding chlorhexidine) on mortality, infection-related ventilator-associated complications (IVACs), and oral health status.

METHODS

The CHORAL study is a stepped wedge, cluster randomized controlled trial in six academic intensive care units (ICUs) in Toronto, Canada. Clusters (ICU) will be randomly allocated to six sequential steps over a 14-month period to de-adopt oral chlorhexidine and implement a standardized oral care bundle (oral assessment, tooth brushing, moisturization, and secretion removal). On study commencement, all clusters begin with a control period in which the standard of care is oral chlorhexidine. Clusters then begin crossover from control to intervention every 2 months according to the randomization schedule. Participants include all mechanically ventilated adults eligible to receive the standardized oral care bundle. The primary outcome is ICU mortality; secondary outcomes are IVACs and oral health status. We will determine demographics, antibiotic usage, mortality, and IVAC rates from a validated local ICU clinical registry. With six clusters and 50 ventilated patients on average each month per cluster, we estimate that 4200 patients provide 80% power after accounting for intracluster correlation to detect an absolute reduction in mortality of 5.5%. We will analyze our primary outcome of mortality using a generalized linear mixed model adjusting for time to account for secular trends. We will conduct a process evaluation to determine intervention fidelity and to inform interpretation of the trial results.

DISCUSSION

The CHORAL study will inform understanding of the effectiveness of de-adoption of oral chlorhexidine and implementation of a standardized oral care bundle for decreasing ICU mortality and IVAC rates while improving oral health status. Our process evaluation will inform clinicians and decision makers about intervention delivery to support future de-adoption if justified by trial results.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT03382730 . Registered on December 26, 2017.

Risk factors for ventilator-associated events: A prospective cohort study

BACKGROUND

In January 2013, the Centers for Disease Control and Prevention released new surveillance definitions for ventilator-associated event (VAE) to replace ventilator-associated pneumonia (VAP) in adult patients. VAEs are associated with prolonged mechanical ventilation and hospital death, but little is known about their risk factors and how best to prevent them.

METHODS

We compared VAE cases with non-VAE cases with regard to demographics, comorbidities, sedative exposures, opioids exposures, paralytic exposures, routes of nutrition, blood products, gastric retention, and fluid balance. Patients mechanically ventilated for ≥4 days between January 1, 2017, and December 31, 2017, in 2 adult intensive care units of a tertiary care teaching hospital in China were included.

RESULTS

On multivariable logistic regression, significant risk factors for VAEs were positive daily fluid balances of ≥ 50 mL between day of intubation and the fourth day of mechanical ventilation (relative risk [RR], 8.39; 95% confidence interval [CI], 2.99-23.50), sedative administered between the first day and the fourth day of invasive mechanical ventilation (RR, 15.69; 95% CI, 1.62-152.06), and daily gastric retention of ≥200 mL between day of intubation and the fourth day of mechanical ventilation (RR, 9.27; 95% CI, 1.89-45.47).

CONCLUSIONS

Positive daily fluid balances of ≥50 mL, sedatives administered, and gastric retention of ≥200 mL are risk factors for VAEs. Intervention studies are needed to determine if targeting these risk factors can lower VAE rates.

Application of the New Centers for Disease Control and Prevention Surveillance Criteria for Ventilator-Associated Events to a Cohort of PICU Patients Identifies Different Patients Compared With the Previous Definition and Physician Diagnosis

OBJECTIVES

We sought to compare the performance of the 2008 Centers for Disease Control and Prevention Pediatric criteria for ventilator-associated pneumonia, the 2013 Adult Ventilator-Associated Condition criteria, the new Draft Pediatric Ventilator-Associated Condition criteria, and physician-diagnosed ventilator-associated pneumonia in a cohort of PICU patients.

DESIGN

Secondary analysis of a previously conducted prospective observational study.

SETTING

PICU within a tertiary care children's hospital between April 1, 2010, and April 1, 2011.

PATIENTS

Patients between 31 days and 18 years old, mechanically ventilated via endotracheal tube for more than 72 hours and no limitations of care.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Ventilator-associated pneumonia criteria applied in real time and ventilator-associated condition criteria applied retrospectively. Outcomes assessed between cases and noncases within criteria. Of the 133 eligible participants, 24 (18%) had ventilator-associated pneumonia by 2008 Pediatric criteria and 27 (20%) by physician diagnosis. Sixteen (12%) and 10 (8%) had ventilator-associated condition by 2013 Adult and Draft Pediatric criteria, respectively. We found significant overlap between cases identified with 2008 Pediatric criteria and physician diagnosis (p = 0.549), but comparisons between the other definitions revealed that the newer criteria identify different patients than previous Centers for Disease Control and Prevention ventilator-associated pneumonia criteria and physician diagnosis (p < 0.01). Although 20 participants were diagnosed with ventilator-associated pneumonia by 2008 Pediatric criteria and physician diagnosis, only three participants were identified by all four criteria. Three subjects uniquely identified by the Draft Pediatric criteria were noninfectious in etiology. Cases identified by all criteria except Draft Pediatric had higher ratios of actual ICU length of stay to Pediatric Risk of Mortality III-adjusted expected length of stay compared with noncases.

CONCLUSIONS

The Draft Pediatric criteria identify fewer and different patients than previous ventilator-associated pneumonia criteria or physician diagnosis, potentially missing patients with preventable harms, but also identified patients with potentially preventable noninfectious respiratory deteriorations. Further investigations are required to maximize the identification of patients with preventable harms from mechanical ventilation.

Evaluating probiotics for the prevention of ventilator-associated pneumonia: a randomised placebo-controlled multicentre trial protocol and statistical analysis plan for PROSPECT

INTRODUCTION

Ventilator-associated pneumonia (VAP) is the most common healthcare-associated infection in critically ill patients. Prior studies suggest that probiotics may reduce VAP and other infections in critically ill patients; however, most previous randomised trials were small, single centre studies. The Probiotics: Prevention of Severe Pneumonia and Endotracheal Colonization Trial (PROSPECT) aims to determine the impact of the probiotic Lactobacillus rhamnosus GG on VAP and other clinically important outcomes in critically ill adults.

METHODS

PROSPECT is a multicentre, concealed, randomised, stratified, blinded, controlled trial in patients ≥18 years old, anticipated to be mechanically ventilated ≥72 hours, in intensive care units (ICUs) in Canada, the USA and Saudi Arabia. Patients receive either 1×10¹⁰ colony forming units of L. rhamnosus GG twice daily or an identical appearing placebo. Those at increased risk of probiotic infection are excluded. The primary outcome is VAP. Secondary outcomes are other ICU-acquired infections including Clostridioides difficile infection, diarrhoea (including antibiotic-associated diarrhoea), antimicrobial use, ICU and hospital length of stay and mortality. The planned sample size of 2650 patients is based on an estimated 15% VAP rate and will provide 80% power to detect a 25% relative risk reduction.

ETHICS AND DISSEMINATION

This protocol and statistical analysis plan outlines the methodology, primary and secondary analyses, sensitivity analyses and subgroup analyses. PROSPECT is approved by Health Canada (#9427-M1133-45C), the research ethics boards of all participating hospitals and Public Health Ontario. Results will be disseminated via academic channels (peer reviewed journal publications, professional healthcare fora including international conferences) and conventional and social media. The results of PROSPECT will inform practice guidelines worldwide.

TRIALREGISTRATION NUMBER

NCT02462590; Pre-results.

Reducing the rare event: lessons from the implementation of a ventilator bundle

The ventilator-associated event (VAE) is a potentially avoidable complication of mechanical ventilation (MV) associated with poor outcomes. Although rare, VAEs and other nosocomial events are frequently targeted for quality improvement efforts consistent with the creed to ‘do no harm’. In October 2016, VA Greater Los Angeles (GLA) was in the lowest-performing decile of VA medical centres on a composite measure of quality, owing to GLA’s relatively high VAE rate. To decrease VAEs, we sought to reduce average MV duration of patients with acute respiratory failure to less than 3 days by 1 July 2017. In our first intervention (period 1), intensive care unit (ICU) attending physicians trained residents to use an existing ventilator bundle order set; in our second intervention (period 2), we updated the order set to streamline order entry and incorporate new nurse-driven and respiratory therapist (RT)-driven spontaneous awakening trial (SAT) and spontaneous breathing trial (SBT) protocols. In period 1, the proportion of eligible patients with SAT and SBT orders increased from 29.9% and 51.2% to 67.4% and 72.6%, respectively, with sustained improvements through December 2017. Mean MV duration decreased from 7.2 days at baseline to 5.5 days in period 1 and 4.7 days in period 2; statistical process control charts revealed no significant differences, but the difference between baseline and period 2 MV duration was statistically significant at p=0.049. Bedside audits showed RTs consistently performed indicated SBTs, but there were missed opportunities for SATs due to ICU staff concerns about the SAT protocol. The rarity of VAEs, small population of ventilated patients and infrequent use of sedative infusions at GLA may have decreased the opportunity to achieve staff acceptance and use of the SAT protocol. Quality improvement teams should consider frequency of targeted outcomes when planning interventions; rare events pose challenges in implementation and evaluation of change.

Among Trauma Patients, Younger Men with Ventilator-Associated Pneumonia Have Worse Outcomes Compared to Older Men-An Exploratory Study

Background: Ventilator-associated pneumonia is associated with significant morbidity. Although the association of gender with outcomes in trauma patients has been debated for years, recently, certain authors have demonstrated a difference. We sought to compare the outcomes of younger men and women to older men and women, among critically ill trauma patients with ventilator-associated pneumonia (VAP). Methods: We reviewed our trauma data base for trauma patients with ventilator-associated pneumonia admitted to our trauma intensive care unit between January 2016 and June 2018. Data collected included demographics, injury mechanism and severity (ISS), admission vital signs and laboratory data and outcome measures including hospital length of stay, ICU stay and survival. Patients were also divided into younger (<50) and older (≥50) to account for hormonal status. Linear regression and binary logistic regression models were performed to compare younger men to older men and younger women to older women, and to examine the association between gender and hospital length of stay (LOS), ICU stay (ICUS), and survival. Results: Forty-five trauma patients admitted to our trauma intensive care unit during the study period (January 2016 to August 2018) had ventilator-associated pneumonia. The average age was 58.9 ± 19.6 years with mean ISS of 18.2 ± 9.8. There were 32 (71.1%) men, 27 (60.0%) White, and 41 (91.1%) had blunt trauma. Mean ICU stay was 14.9 ± 11.4 days and mean total hospital length of stay (LOS) was 21.5 ± 14.6 days. Younger men with VAP had longer hospital LOS 28.6 ± 17.1 days compared to older men 16.7 ± 6.6 days, (p < 0.001) and longer intensive care unit stay 21.6 ± 15.6 days compared to older men 11.9 ± 7.3 days (p = 0.02), there was no significant difference in injury severity (ISS was 22.2 ± 8.4 vs. 17 ± 8, p = 0.09). Conclusions: Among trauma patients with VAP, younger men had longer hospital length of stay and a trend towards longer ICU stay. Further research should focus on the mechanisms behind this difference in outcome using a larger database.

Relationship between Ventilator-Associated Events and Timing of Rehabilitation in Subjects with Emergency Tracheal Intubation at Early Mobilization Facility

The present study aimed to investigate the relationship between the occurrence of ventilator-associated events (VAE) in the intensive care unit and the timing of rehabilitation intervention. We included subjects who underwent emergency tracheal intubation and received rehabilitation. We performed rehabilitation according to our hospital’s protocol. We assessed the mechanical ventilation parameters of inspired oxygen fraction and positive-end expiratory pressure, and a VAE was identified if these parameters stabilized or decreased for ≥2 days and then had to be increased for ≥2 days. We defined time in hours from tracheal intubation to the first rehabilitation intervention as Timing 1 and that to first sitting on the edge of the bed as Timing 2. Data were analyzed by the t-test and χ² tests. We finally analyzed 294 subjects. VAE occurred in 9.9% and high mortality at 48.3%. Median values of Timing 1 and Timing 2 in the non-VAE and VAE groups were 30.3 ± 24.0 and 30.0 ± 20.7 h, and 125.7 ± 136.6 and 127.9 ± 111.4 h, respectively, and the differences were not significant (p = 0.95 and p = 0.93, respectively). We found no significant relationship between the occurrence of VAE leading to high mortality and timing of rehabilitation intervention.

Ventilator-associated events in children: A review of literature

BACKGROUND

The complexity and variation in ventilator associated pneumonia (VAP) definitions in paediatrics may pose threats to the reliable identification of VAP. The revision of the surveillance definition to ventilator-associated event (VAE) has been mandated in adult populations, to overcome these issues. However, the evidence for application of the definition is unknown in children.

OBJECTIVES

To review the evidence on the application of the new VAE surveillance definition in paediatric population and examine the potential challenges in clinical practice.

REVIEW METHODS

A systematic approach was used to locate and synthesise the relevant paediatric literature. Studies were appraised according to epidemiological appraisal instrument (EAI) and the grades of evidence in the National Health Medical Research Council (NHMRC) guidelines.

RESULTS

Seven studies met the inclusion criteria. Quality of study methods was above 50% on the EAI. The overall grade of evidence was assessed as C (satisfactory). The incidence of VAE in children ranged from 1.1 to 20.9 per 1000 ventilator days as a result of variations in surveillance criteria across included studies. There is little agreement between the new VAE and PNU/VAP surveillance definition in the identification of VAP. Challenges in the application of VAE surveillance were related to; the difference in modes of ventilation used in children versus adults, inconclusive criteria tailored to paediatric samples and a lack of data that support for automatic data extraction applied in paediatric studies.

CONCLUSION

This review demonstrated promising evidence using the new VAE surveillance definition to define the VAE in children, but the level of the evidence is low. Before the possibility of real implementation in clinical settings, challenges related to VAE paediatric specific criteria' and the value of automated data collection need to be considered.

Ventilator-associated events: prevalence and mortality in Japan

Background

In 2013, the Centers for Disease Control and Prevention (CDC) issued the concept of the ventilator-associated events (VAEs) as a quality indicator (QI) in the intensive care unit (ICU). A number of studies have been conducted in the United States and other Western countries to evaluate its practicality. However, information on VAEs in non-Western countries is scarce. The purpose of this preliminary study was to illuminate the incidence and associated mortality rate of VAEs in Japan, as a first step in the effort to determine its practicality.

Methods

We conducted a multi-center, retrospective review of patient medical record using VAEs surveillance algorithm. We analyzed 785 patients with ≥2 days of mechanical ventilator (MV), admitted to the ICU at seven urban hospital in Japan. The prevalence of VAEs, including its three subtypes, and in-ICU mortality were researched.

Results

Forty-nine VAEs were identified, affecting 5.7% of patients requiring MV for ≥2 days and 6.4 per 1,000 MV days. Mortality in those who developed VAEs was 42.9%, significantly higher than the rest of the cohort (vs. 15.4%, P<0.001). The overall equivalent distribution of the three VAEs subtype incidences was evaluated: the incidences of VAC only, IVAC only and PVAP were 2.20, 1.90 and 2.29 per 1,000 MV days respectively (P=0.933). However, VAE etiology and mortality was facility dependent. ICUs with a large proportion of surgical patients and more severe cases tended to have increased VAE incidence, with a converse decrease in closed ICUs.

Conclusions

The prevalence of VAEs appears low in Japanese ICUs. Nonetheless, mortality was substantially higher in patients who developed VAEs. Although some potential indices of VAEs are suggested to serve as QIs, additional studies to elaborate its practicality would further be required.

Limiting ventilator-associated complications in ICU intubated subjects: strategies to prevent ventilator-associated events and improve outcomes

Introduction: Intubation is required to maintain the airways in comatose patients and enhance oxygenation in hypoxemic or ventilation in hypercapnic subjects. Recently, the Centers of Disease Control (CDC) created new surveillance definitions designed to identify complications associated with poor outcomes. Areas covered: The new framework proposed by CDC, Ventilator-Associated Events (VAE), has a range of definitions encompassing Ventilator-Associated Conditions (VAC), Infection-related Ventilator-Associated Complications (IVAC), or Possible Ventilator-Associated Pneumonia - suggesting replacing the traditional definitions of Ventilator-Associated Tracheobronchitis (VAT) and Ventilator-Associated Pneumonia (VAP). They focused more on oxygenation variations than on Chest-X rays or inflammatory biomarkers. This article will review the spectrum of infectious (VAP & VAT) complications, as well as the main non-infectious complications, namely pulmonary edema, acute respiratory distress syndrome (ARDS) and atelectasis. Strategies to limit these complications and improve outcomes will be presented. Expert commentary: Improving outcomes should be the objective of implementing bundles of prevention, based on risk factors amenable of intervention. Promotion of measures that reduce the exposition or duration of intubation should be a priority.

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.

Can probiotics be an alternative to chlorhexidine for oral care in the mechanically ventilated patient? A multicentre, prospective, randomised controlled open trial

Background

Pathogenic enteric bacteria aspirated from the oropharynx are the main cause of ventilator-associated pneumonia (VAP). Using chlorhexidine (CHX) orally or selective decontamination has been shown to reduce VAP. In a pilot study we found that oral care with the probiotic bacterium Lactobacillus plantarum 299 (Lp299) was as effective as CHX in reducing enteric bacteria in the oropharynx. To confirm those results, in this expanded study with an identical protocol we increased the number of patients and participating centres.

Methods

One hundred and fifty critically ill patients on mechanical ventilation were randomised to oral care with either standard 0.1% CHX solution (control group) or a procedure comprising final application of an emulsion of Lp299. Samples for microbiological analyses were taken from the oropharynx and trachea at inclusion and subsequently at defined intervals.

Student’s t test was used for comparisons of parameters recorded daily and Fisher’s exact test was used to compare the results of microbiological cultures.

Results

Potentially pathogenic enteric bacteria not present at inclusion were identified in oropharyngeal samples from 29 patients in the CHX group and in 31 samples in the probiotic group. Considering cultures of tracheal secretions, enteric bacteria were found in 17 and 19 samples, respectively. Risk ratios show a difference in favour of the Lp group for fungi in oropharyngeal cultures. VAP was diagnosed in seven patients in the Lp group and in 10 patients among the controls.

Conclusions

In this multicentre study, we could not demonstrate any difference between Lp299 and CHX used in oral care procedures regarding their impact on colonisation with emerging potentially pathogenic enteric bacteria in the oropharynx and trachea.

Trial registration

ClinicalTrials.gov, NCT01105819. Registered on 9 April 2010.

First part: Current Controlled Trials, ISRCTN00472141. Registered on 22 November 2007 (published Critical Care 2008, 12:R136).

Hospital-Acquired Infections in Critically Ill Patients With Cancer

Hospital-acquired infections are a common and costly problem facing critically ill patients in the intensive care unit (ICU). Critically ill patients with cancer are a particularly vulnerable subpopulation who possesses additional, nonmodifiable risk factors for developing these infections and, in many cases, are at increased risk of death as a result. This review will describe the most common nosocomial infections patients with cancer acquire while in the ICU: ventilator-associated events, central line-associated bloodstream infection, catheter-associated urinary tract infections, and Clostridium difficile infection.

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.

Impact of the Antibiotic Stewardship Program on Prevention and Control of Surgical Site Infection during Peri-Operative Clean Surgery

BACKGROUND

Surgical site infections (SSIs) are the leading cause of hospital-acquired infections and are associated with substantial healthcare costs, with increased morbidity and mortality. To investigate the effects of the antibiotic stewardship program on prevention and control of SSI during clean surgery, we investigated this situation in our institution.

PATIENTS AND METHODS

We performed a quasi-experimental study to compare the effect before and after the antibiotic stewardship program intervention. During the pre-intervention stage (January 1, 2010 through December 31, 2011), comprehensive surveillance was performed to determine the SSI baseline data. In the second stage (January 1, 2012 through December 31, 2016), an infectious diseases physician and an infection control practitioner identified the surgical patients daily and followed up on the duration of antimicrobial prophylaxis.

RESULTS

From January 1, 2010 to December 31, 2016, 41,426 patients underwent clean surgeries in a grade III, class A hospital. The rate of prophylactic antibiotic use in the 41,426 clean surgeries was reduced from 82.9% to 28.0% after the interventions. The rate of antibiotic agents administered within 120 minutes of the first incision increased from 20.8% to 85.1%. The rate at which prophylactic antimicrobial agents were discontinued in the first 24 hours after surgery increased from 22.1% to 60.4%. Appropriate antibiotic selection increased from 37.0% to 93.6%. Prophylactic antibiotic re-dosing increased from 3.8% to 64.8%. The SSI rate decreased from 0.7% to 0.5% (p < 0.05). The pathogen detection rate increased from 16.7% up to 41.8% after intervention. The intensity of antibiotic consumption reduced from 74.9 defined daily doses (DDDs) per 100 bed-days to 34.2 DDDs per 100 bed-days after the interventions.

CONCLUSION

Long-term and continuous antibiotic stewardship programs have important effects on the prevention and control of SSI during clean surgery.

Ventilator-associated events after cardiac surgery: evidence from 1,709 patients

Background

Ventilator-associated event (VAE) is a new surveillance for nosocomial infections in mechanically ventilated patients. To date, little is known about VAEs after cardiac surgeries. The present study firstly focused on patients who have undergone heart operations, intending to draw a comprehensive description of VAEs.

Methods

Postoperative patients from September 2012 to December 2015 were monitored for VAEs. By reviewing electronic medical records and preserved files retrospectively, clinical data were further analyzed.

Results

A total of 1,709 adult patients were enrolled, of which 166 episodes met the criteria for VAE. The mean incidence rate reached up to 9.7% and 49.9 per 1,000 mechanical ventilation days. By using both univariate analysis and multiple logistic regression analysis, chronic obstructive pulmonary disease (COPD), left ventricle ejection fraction (LVEF) <30%, cardiopulmonary bypass time, aortic clamping time, mechanical ventilation time, reintubation, dosage of blood products and acute kidney injury (AKI) were found to be risk factors for VAEs. Compared with non-VAE group, VAEs were closely related to higher mortality, longer intensive care unit stay time and hospitalization time. In addition, 91 strains of pathogens were isolated from endotracheal aspirates of 81 patients with VAE, of which Pseudomonas aeruginosa was the most common pathogenic microorganism (30 isolates, 37.0%), followed by Acinetobacter baumannii (27 isolates, 33.3%) and other five types.

Conclusions

VAE algorithm is a valid and reliable surveillance for possible infections caused by mechanical ventilation, which could easily occur in patients after cardiac surgery and is associated with poor prognosis. The risks and pathogens that we have investigated will provide potential preventive strategies.