Diagnosis Of Ventilator-associated Pneumonia Research Articles

P-428. Impact of Diagnostic Stewardship Interventions on Ventilator-Associated Event Rates

Abstract Background Ventilator-associated events (VAEs) are CDC/NHSN surveillance definitions for monitoring nosocomial complications from invasive mechanical ventilation. In 2022, we executed the Diagnosis of Ventilator-Associated Pneumonia (DIVA) trial (NCT05176353), a quasi-experimental pilot/feasibility clinical trial of a VAP bundled diagnostic stewardship intervention (VAP-DSI) targeting the ICU respiratory culturing pathway. This VAP-DSI associated with a 20% rate reduction in positive respiratory cultures per 1000 mechanically ventilated patient days. In this post hoc analysis, we present a secondary data analysis evaluating the impact of a VAP-DSI on VAE surveillance rates. Methods The DIVA trial operationalized a VAP-DSI using an interruptive clinical decision support tool and modifications to clinical laboratory workflows. Interventions included gatekeeping access to respiratory culture ordering, preferential use of non-bronchoscopic bronchoalveolar lavage for culture collection, and suppression of culture results for samples with minimal alveolar neutrophilia. We compared monthly VAE rates among study ICUs (those that utilized the VAP-DSI) and non-study ICUs over both a 5-year pre-intervention period (2017-2022) and the post-intervention period (2022-2023). Event rates were compared using a Z-test approximation for person-time rates. Results Figure 1 demonstrates monthly VAE rates stratified by ICU and pre- vs post-intervention time periods. Study ICUs demonstrated significant decreases in rates of VAEs, VACs, and PVAPs following VAP-DSI implementation. Conversely, non-study ICUs experienced no significant changes in VAE rates. Conclusion In this single-center pilot/feasibility clinical trial, diagnostic stewardship interventions targeting the ICU respiratory culturing pathway associated with significant reductions in VACs, PVAPs, and total VAEs. These findings suggest a potential impact of diagnostic stewardship interventions on VAE surveillance rates. Disclosures All Authors: No reported disclosures

P-244. Antibiotic Prescribing Patterns in Ventilator Associated Pneumonia and their Effect on Carbapenem Resistant Organism Colonisation in Asian Hospitals

Abstract Background Ventilator-associated pneumonia (VAP) is associated with prolonged hospitalisation, excessive antibiotic use and high mortality. Antibiotic regimens used for VAP and their effect on development of carbapenem resistant (CR) organisms (CRO) have not been well characterised, especially in Asia.Table 1.Antibiotics used for index episode of VAP caused by carbapenem resistant organisms, and overall carbapenem use Methods The REGARD-VAP study was a randomised trial conducted in 39 intensive care units in Nepal, Singapore and Thailand. Adults aged ≥18 years with VAP (defined by the US CDC and Prevention National Healthcare Safety Network criteria), who had been mechanically ventilated for ≥48 hours, and received culture-directed antibiotics were enrolled. In culture-negative cases, antibiotics were prescribed as per local hospital antibiograms. We analysed the antibiotics prescribed in VAP and their association with CRO acquisition. We also assessed the effect of CRO colonisation on 60-day mortality and VAP recurrence.Table 2.Factors associated with new carbapenem-resistant organism (CRO) isolation in microbiological samples in a multivariable logistic regression model Carbapenem use for index episode of VAP was independently associated with higher odds ratio of new CRO colonization when adjusted for duration of antibiotics, and length of hospital stay. Duration of ICU stay was not included in this model due to high collinearity with length of hospital stay. Results The study enrolled 460 participants and the majority (47.4%) of VAP was caused by Gram-negative non-fermenters (VAPnf). Amongst participants with CR VAPnf, 56 (45.5%) received colistin-based regimens and 48 (39.0%) received beta-lactams. Amongst those with CR Enterobacterales, 11 (44.0%) received either a colistin-based regimen or beta-lactams. 52 different antibiotic regimens were used to treat CR VAP, and only one participant received a novel beta-lactam/beta-lactamase inhibitor (Ceftazidime-avibactam). 45.9% of all antibiotic regimens included carbapenems which was independently associated with new acquisition of CRO during the study period (OR 1.80, 95% CI 1.10 – 2.93, p=0.019). In a Cox regression model, CRO colonization (n=176, 38.3%) was associated with higher 60-day mortality (HR 1.66 (95%CI 1.21 – 2.28), p=0.002) and VAP recurrence (HR 8.37 (95% CI 4.28 – 16.38), p< 0.001) when adjusted for demographic factors, disease severity, comorbidities, antibiotic duration, and VAPnf.Figure 1.Cox-Regression Survival analysis showing 60-day mortality (left) and 60-day VAP recurrence (right) in participants with or without Carbapenem Resistant Organism (CRO) colonization. 60-day mortality and VAP recurrence was adjusted for demographic factors (patient age and gender), disease severity (qSOFA score and inotropic requirement at VAP diagnosis), comorbidities (Charlson comorbidity index and presence of congestive cardiac failure, acute coronary syndrome, chronic obstructive pulmonary disease, chronic kidney disease, cirrhosis, cancer, diabetes), duration of antibiotics prescribed for index episode of VAP, use of appropriate empiric antibiotics to which the organism was susceptible prior to switching to culture-directed antibiotics and cause of VAP (presence/ absence of Gram-negative non-fermenter). Participants with CRO colonization had increased hazards ratio of mortality and VAP recurrence. Conclusion In lower, middle- and high-income countries in Asia, variable antibiotic regimens were used for the treatment of VAP, majority consisting of colistin and carbapenem based regimens, with the latter being associated with higher rates of new CRO isolation. There is a need for better treatment options for these difficult to treat pathogens across the income spectrum in Asia. Disclosures Paul Tambyah, MBBS (S'pore), Diplomate, American Board of Internal Medicine and Infectious Diseases, Moderna: Grant/Research Support|Sanofi-Pasteur: Grant/Research Support

P-287. Risk factors for Pseudomonas aeruginosa in ICU-Related Respiratory Infections. An analysis from the European Network for ICU-Related Respiratory Infections (ENIRRIs) study

Abstract Background Nosocomial low respiratory infections (nLRTIs) represent a significant complication prevalent among patients who require admission to the intensive care unit (ICU). Gram-negative microorganisms are related to nLRTIs, such as ventilator-associated pneumonia (VAP), ventilator-associated tracheobronchitis (VAT), ICU-acquired pneumonia (ICU-HAP), and hospital-acquired pneumonia (HAP). Pseudomonas aeruginosa (PA) is frequently identified among nLRTIs; however, not all patients with nLRTI may require antipseudomonal treatment and this is not clear in the literature. This study aims to describe the characteristics and principal outcomes of patients with confirmed PA nLRTI. Table 1. Characteristics of patients with Pseudomonas aeruginosa identification Vs Non-Pseudomonas aeruginosa identification. Methods This prospective cohort was conducted in 12 countries over two continents from 9th May 2016 until 16th August 2019. Characteristics and outcomes of nLRTI’s patients admitted to the ICU were collected. All patients were tested to find microbiological-causing agents. Patients with confirmed isolation for PA were compared to patients with non-PA isolation. The Mam Whitney and Chi-squared were used to compare the group's proportions depending on their distribution. Table 2. Bivariate analysis for risk factors associated with Pseudomonas aeruginosa Results 1059 patients with nLRTIs who underwent testing for microbiological diagnosis were included, 14.4% patients had confirmed infection by PA. 74% were male with a median age of 64 (49-73) years old. The principal diagnosis among patients with PA was VAP. The principal comorbidities were diabetes and heart disease, followed by COPD. The most frequent complication was septic shock, followed by acute kidney injury. There were differences among the comorbidities, complications and outcomes among the groups (Table 1). However, there were no differences in mortality (Table 1 - Figure 1). VAT and VAP diagnosis, COPD Gold D and AKI on the 1st day were associated with a high risk of infection by PA (Table 2). Figure 1. Sankey diagram showing mortality outcome. Pseudomonas aeruginosa Vs. Non-Pseudomonas aeruginosa LRTI-diagnosed patients who were admitted to the ICU. Conclusion This multi-country study found some important risk factors associated with PA in nLRTI patients. Differences among groups were notorious; diabetes and COPD comorbidities are more frequent among PA nLRTI patients. Finally, PA infection increases the length of stay of patients. Further studies are needed to confirm these findings. Disclosures All Authors: No reported disclosures

Ventilator-Associated Pneumonia After Cardiac Arrest and Prevention Strategies: A Narrative Review.

Background and Objectives: Ventilator-associated pneumonia (VAP) poses a significant threat to the clinical outcomes and hospital stays of mechanically ventilated patients, particularly those recovering from cardiac arrest. Given the already elevated mortality rates in cardiac arrest cases, the addition of VAP further diminishes the chances of survival. Consequently, a paramount focus on VAP prevention becomes imperative. This review endeavors to comprehensively delve into the nuances of VAP, specifically in patients requiring mechanical ventilation in post-cardiac arrest care. The overarching objectives encompass (I) exploring the etiology, risk factors, and pathophysiology of VAP, (II) delving into available diagnostic modalities, and (III) providing insights into the management options and recent treatment guidelines. Methods: A literature search was conducted using PubMed, MEDLINE, and Google Scholar databases for articles about VAP and Cardiac arrest. We used the MeSH terms "VAP", "Cardiac arrest", "postcardiac arrest syndrome", and "postcardiac arrest syndrome". The clinical presentation, diagnostic, and management strategies of VAP were summarized, and all authors reviewed the selection and decided which studies to include. Key Content and Findings: The incidence and mortality rates of VAP exhibit significant variability, yet a recurring pattern emerges, marked by prolonged hospitalization and exacerbated clinical outcomes. This pattern is attributed to the elevated incidence of drug-resistant infections and the delayed initiation of antimicrobial treatment. This review focuses on VAP, aiming to offer valuable insights into the efficient identification and management of this fatal complication in post-cardiac arrest patients. Conclusion: The prognosis for survival after cardiac arrest is already challenging, and the outlook becomes even more daunting when complicated by VAP. The timely diagnosis of VAP and initiation of antibiotics pose considerable challenges, primarily due to the invasive nature of obtaining high-quality samples and the time required for speciation and identification of antimicrobial sensitivity. The controversy surrounding prophylactic antibiotics persists, but promising new strategies have been proposed; however, they are still awaiting well-designed clinical trials.

The impact of the Centers for Disease Control and Prevention new surveillance definitions of ventilator-associated event on our clinical practice

ABSTRACT Objective Surveillance of ventilator-associated pneumonia is subjective, inaccurate, time-consuming, and does not predict outcomes. The Centers for Disease Control and Prevention (CDC) recommended the use of ventilator-associated event (VAE) definitions instead of ventilator-associated pneumonia (VAP) in 2013. Therefore, we evaluated this novel surveillance algorithm by comparing the results of our VAP and VAE methods. Material Methods We evaluated mechanically ventilated adult medical and surgical patients in our 13-bed intensive care unit (ICU). Nine patients diagnosed with VAP in 2018-2019 and 11 patients diagnosed with VAE in 2022-2024 were retrospectively evaluated. The impact of the new definitions on clinical processes such as days on the mechanical ventilator, duration of antibiotic use, ICU stay in determining infectious status was monitored. Results. Statistical analysis revealed that demographic and numeric data were similar in both VAP and VAE diagnosis groups (p

‘Effectiveness of various sulbactam-based combination antibiotic therapy in the management of ventilator-associated pneumonia caused by carbapenem-resistant Acinetobacter baumannii in a tertiary care Health centre’

ObjectiveCarbapenem-resistant Acinetobacter baumannii (CRAB) is a common cause of ventilator-associated pneumonia (VAP). Some in vitro data favour various combination antibiotic therapy. However, there is a need for more in vivo studies for the management of VAP caused by CRAB. This retrospective study was done to evaluate the effectiveness of various combination antibiotic therapy including sulbactam on outcomes of VAP caused by CRAB. MethodsAdult patients (age ≥18 years) diagnosed with VAP caused by CRAB were included. Patients with polymicrobial infections were excluded from the study. Patients with CRAB associated VAP who were given sulbactam based antibiotic combinations were observed for outcomes. The primary outcome was 28-day mortality after diagnosis of VAP caused by CRAB. Reduction in serum HsCRP (High sensitivity C-reactive protein) during treatment and requirement of inotropes were the secondary outcomes. Outcomes were compared between various sulbactam based antibiotic combination therapies. ResultsA total of 103 patients were included. A total of 44 (42.7 %) patients received sulbactam and minocycline or sulbactam and polymyxin B dual antibiotic combination, and 59 (57.3 %) patients received sulbactam, polymyxin B and minocycline triple antibiotic combination. The percentage difference in 28 days mortality was 27.51 % (95 % CI 8.03 %–44.06 %; p = 0.005) in dual vs triple sulbactam based antibiotic combination therapy. The percentage difference in requirement of inotropes during therapy and HsCRP reduction after 7 days of therapy was 23.65 % (95 % CI 6.43 %–38.3 %; p = 0.007) and 25.1 % (95%CI 10.1 %–38.2 %; p < 0.001) respectively when compared between dual vs triple sulbactam based antibiotic combination therapy. ConclusionTreatment with sulbactam, polymyxin B and minocycline combination antibiotic therapy was associated with significantly lower 28-day mortality. Moreover, the lower requirement of inotropes during treatment and a significant reduction in HsCRP level favours this combination antibiotic therapy in VAP caused by CRAB.

Prevalence and etiology of ventilator-associated pneumonia during the COVID-19 pandemic in Denmark: Wave-dependent lessons learned from a mixed-ICU.

Ventilator-associated pneumonia (VAP) may be a particular concern in patients with severe coronavirus disease 2019 (COVID-19). We aimed to determine the prevalence and etiology of VAP in critically ill COVID-19 patients in a Danish intensive care unit (ICU) during the first three waves of the COVID-19 pandemic and to study associations between dexamethasone (DXM) use and development of VAP. In an observational single-center study patients were retrospectively screened for VAP including causative pathogens, use of DXM and commonly used antibiotics. Diagnosis of VAP required invasive mechanical ventilation (IMV) >48 h with presence of a new bacterial agent and clinical signs of infection. For analysis, common descriptive statistics were applied. Cox proportional hazards models were used to analyze the association between DXM use and VAP. VAP was detected in 53/119 (44.5%) mechanically ventilated patients across all three COVID-19 waves. Median length of IMV for VAP patients was 24 [15-41] days, and 3 out of 4 were males. VAP was most prevalent (47.0%) during the second wave. Common pathogens included Klebsiella pneumoniae (24.5%), Enterobacter aerogenes (17.0%) and Pseudomonas aeruginosa (13.2%), Staphylococcus aureus (13.2%), and Escherichia coli (13.2%). A change from Gram-negative bacteria only to a combination of Gram-positive and Gram-negative bacteria was observed in the second wave compared to first. Use of DXM was not associated with VAP (adjusted hazard ratio 1.63 95% CI: 0.84-3.17). The prevalence of VAP was high across all three COVID-19 waves and showed a different distribution of pathogens between the first and second wave. Use of DXM was not associated with VAP development. Further and larger studies are needed to understand the risk factors associated with VAP in patients with COVID-19.

EVALUATION OF THE ROLE OF SELECTIVE DIGESTIVE TRACT DECONTAMINATION IN PREVENTION OF VENTILATOR ASSOCIATED PNEUMONIA IN INTENSIVE CARE UNIT PATIENTS

Ventilator-associated pneumonia (VAP) is a significant nosocomial infection in critically ill patients, contributing to increased morbidity, mortality, and healthcare costs. The incidence of VAP in intensive care units (ICUs) ranges from 7% to 40%, with mortality rates potentially exceeding 50%1. Recent studies highlight that VAP affects approximately 27% of all critically ill patients, with 86% of these infections associated with mechanical ventilation. The attributable mortality of VAP varies, with some studies reporting an increase in mortality of up to 27%3. Pathogens such as Pseudomonas aeruginosa, Acinetobacter, and Stenotrophomonas maltophilia are linked to higher mortality rates4. Beyond mortality, VAP significantly extends ICU length of stay and increases healthcare costs5. The gastrointestinal tract plays a crucial role in VAP pathogenesis, as it often becomes colonized with Gram-negative bacteria during critical illness6. Interventions such as selective decontamination of the digestive tract (SDD), stress ulcer prophylaxis with sucralfate, and enteral feeding strategies are employed to reduce VAP incidence. While SDD has been shown to decrease VAP incidence and may positively impact mortality, it also poses a risk of promoting Gram-positive bacterial infections. SDD involves the use of non-absorbable antibiotics applied topically to the oropharynx and through a nasogastric tube, often supplemented with systemic antibiotics during the initial days of ICU admission. Recent guidelines and systematic reviews continue to emphasize the importance of accurate VAP diagnosis and effective antimicrobial therapy to improve patient outcomes and reduce healthcare burdens.

Lung Ultrasound Score as a Predictor of Clinical Severity and Prognosis in Patients of Ventilator-associated Pneumonia.

To estimate a correlation between change in lung ultrasound aeration score (LUSS) and mortality in patients with ventilator-associated pneumonia. We conducted a prospective observational study in which lung ultrasound, the partial pressure of arterial oxygen to fraction of inspired oxygen ratio (PaO2/FiO2 ratio), and static lung compliance were performed for five consecutive days since the diagnosis of ventilator-associated pneumonia (day 1-5) in a 20-bed multidisciplinary intensive care unit in at a tertiary care academic institute in Northern India. A hundred and seventeen ventilated patients were studied for the first 5 days after ventilator-associated pneumonia (VAP) development. Lung ultrasounds were performed with an ultrasonography machine using a round-tipped probe of 2-5 MHz at six different areas of each hemithorax, which includes superior and inferior in anterior, lateral, and posterior lung fields. Patients with a decreased LUSS of 2 were labeled as responders. A decrease of LUSS of less than 2 or an increase of LUSS were leveled as nonresponders. The correlation between the change in LUSS between days 1 and 5 was significant with 28-day mortality (26.3% in responders vs 87.8% nonresponses with p < 0.001). The responders to treatment for VAP described by LUSS had lower mortality than non-responders. Panda S, Agarwal A, Mishra SB, Jain G, Talawar P. Lung Ultrasound Score as a Predictor of Clinical Severity and Prognosis in Patients of Ventilator-associated Pneumonia. Indian J Crit Care Med 2024;28(11):1009-1014.

Diagnostic and Prognostic Value of Tracheal Aspirate Procalcitonin Level in Critically Ill Pediatric Patients with Ventilated Associated Pneumonia

Abstract Background Ventilator associated pneumonia(VAP) is the second most common hospital acquired infection (HAI) after blood stream infection in the pediatric age group, accounting for about 20% of all HAIs in the pediatric intensive care units (PICUs) and has a rate of 2.9- 21.6 per 1000 ventilator days. VAP should be suspected in patients with a new or progressive pulmonary infiltrate on imaging plus supportive clinical findings of infection (e.g., fever, secretions, leukocytosis). The diagnosis is confirmed when lower respiratory tract sampling identifies pathogen. Aim of the Work To assess diagnostic and prognostic value of tracheal aspirate procalcitonin level in critically ill pediatric patients with VAP. Patients and Methods This prospective cohort study was conducted on 50 ventilated patients collected from Pediatric Intensive Care Unit, Ain Shams University Children's hospital in a period of 6 months starting from June 2023 till December 2023; they were divided into two groups VAP group and non VAP group. They were 26 females (52.0%) and 24 males (48%) with age ranged from 0.17 – 7 years and with median (IQR) of 1.75 (0.56 – 3). Results Regarding to our study procalcitonin (PCT) measured for 50 ventilated patietns at day 1 showed median IQR 269.85 pg/ml(183.7pg/ml–646.8pg/ml) with range 72.3pg/ml–2500pg/ml. At day 3 studeid patients divided into 2 groups VAP and non VAP group according to centers of disease control(CDC) criteria of VAP diagnosis and with comparing PCT level at day 3 between 2 groups showed statistically significant increase in the level of procalcitonin at day 3 in VAP group [574.9pg/ml(362pg/ml – 719pg/ml)] than non VAP group [280pg/ml(192.9pg/ml – 555pg/ml)] with p-value = 0.026 and the best cut off point for procalcitonin level at day 3 to differentiate between VAP and non VAP groups was found &amp;gt; 255.4pg/ml with sensitivity of 92%, specificity of 48% and area under curve (AUC) of 68.3%. Among VAP group procalcitonin level measured at Broncho alveolar lavage (BAL) and serum at the same time and incomparing two levels there was no statitically significant difference found between level of PCT in BAL and serum with p-value 0.778. PCT as a prognostic marker it showed PCT level, significantly increase at day 3 and onset of VAP in BAL and serum in died patients than discharged patients with p-value = 0.003, 0.031 and 0.005; respectively. Conclusion This study underscores the significant diagnostic and prognostic value of procalcitonin levels in critically ill pediatric patients with (VAP). Procalcitonin levels, especially at day 3, demonstrated good diagnostic performance in differentiating between VAP and non-VAP cases. Additionally, procalcitonin levels in bronchoalveolar lavage (BAL) and serum at the onset of VAP emerged as highly reliable markers for confirming the presence of VAP, with excellent sensitivity and specificity. These findings highlight the potential for procalcitonin to aid in the early diagnosis and management of VAP in this vulnerable patient population, ultimately contributing to improved clinical outcomes and patient care in intensive care settings.

Is Ventilator-associated Event Algorithm Ideal for Surveillance? – Experience from a Neurosurgery Intensive Care Unit in Kerala

Background: The ventilator-associated event (VAE) surveillance algorithm was brought in to replace the clinical ventilator-associated pneumonia (VAP) surveillance by NHSN in January 2013. This study intends to find the correlation of these surveillance criteria with the clinical VAP rates in a neurosurgery intensive care unit (ICU). Materials and Methods: This was a retrospective analysis of records of patients undergoing invasive mechanical ventilation in a neurosurgery ICU during a 3-month period. Results: Thirty-seven patients underwent invasive mechanical ventilation. The mean age was 56 years. Hypertension was the most common comorbidity among 22 (59.4%) patients. The neurological diagnosis was traumatic brain injury in 19 cases, nontraumatic intracranial hemorrhage in 12 cases, and ischemic stroke in 6 cases. Twenty-one patients had respiratory sample culture positivity and 14 were clinical VAP. The total ventilator days assessed were 82. The clinical VAP rate was 170.7, and the probable VAP (PVAP) rate for the same period was 12.19. Among the 14 patients who developed clinical VAP, 13 (88%) were hospital acquired and caused by multidrug-resistant pathogens. Six patients died during their ICU stay. ICU stay of more than 7 days was significantly associated with a clinical VAP. Conclusions: VAE was found to correlate poorly with a clinical diagnosis of VAP. When used as a surveillance tool in an ICU, it was found to miss important infection-related events in ventilated patients.

Predictors of treatment failure following early antibiotic discontinuation in culture-negative, ventilator-associated pneumonia: an observational study.

Early antibiotic discontinuation in clinically suspected ventilator-associated pneumonia (VAP) may lead to infection relapse/recurrence and increase mortality. This study aimed to evaluate the incidence and potential predictors of treatment failure with this approach. A retrospective observational study was conducted between September 2014 and November 2016 in a mixed intensive care unit. We included clinically suspected VAP patients whose quantitative sputum cultures from endotracheal aspirate were negative, allowing antibiotic discontinuation within 24 hours. Patients were monitored for signs and symptoms of recurrent VAP. Incidence and risk factors for treatment failure, defined as pneumonia recurrence, were determined using univariate logistic regression analysis and receiver operating characteristic (ROC) curves. Forty-three patients met the inclusion criteria. The incidence of treatment failure among culture-negative VAP following early antibiotic discontinuation was 27.9% (12 patients). There were no significant differences in procalcitonin levels, leukocyte counts or body temperature between the two groups, except for the modified clinical pulmonary infection score (mCPIS) (5.42 ± 2.19 versus 3.9 ± 1.54, p = 0.014). Procalcitonin levels at VAP diagnosis and antibiotic cessation both showed low predictive capacity for treatment failure (AUC 0.56, CI 95% 0.36-0.76 and AUC 0.57, CI 95% 0.37-0.76, respectively). However, combining mCPIS with procalcitonin improved the predictive value for treatment failure (AUC 0.765, CI 95% 0.56-0.96). Early antibiotic discontinuation may lead to a high incidence of treatment failure among culture-negative VAP patients. Procalcitonin alone should not guide antibiotic discontinuation decisions while combining mCPIS and procalcitonin enhances predictive accuracy for treatment failure.

Diagnosis of Ventilator-Associated Pneumonia – A Systematic Review and Meta-analysis of Laboratory Techniques

Hospitalized patients on mechanical ventilation are at high-risk of developing ventilator-associated pneumonia (VAP), making early and accurate diagnosis essential for the best possible treatment outcomes. This review examined various laboratory techniques, such as aerobic cultures, Gram’s stain, and molecular techniques, to assess how well they diagnose VAP. We have done search strategies using Google Scholar, Medline Complete, and PubMed. Extensive statistical tools were utilized to examine studies and evaluate the diagnostic accuracy of laboratory results. Multiplex PCR was superior to Gram’s stain and culture methods in terms of sensitivity (92%) and specificity (86%). On the other hand, Gram’s stain showed the highest specificity (78.9%) and the lowest sensitivity (74.6%). The results of semi-quantitative, quantitative, enrichment culture showed a lower specificity (75.97%) but a moderate sensitivity (78.5%). The most accurate diagnostic approach for VAP, according to a meta-analysis, was multiplex PCR-based testing, closely followed by culture methods. Beyond separate tests, multiplex PCR, culture, and Gram’s stain combination increased sensitivity. Prompt and precise VAP diagnosis is essential for efficient treatment. With possible improvements through combination diagnostic techniques, multiplex PCR remains the most accurate diagnostic tool. However, more investigation is necessary to improve and certify VAP diagnostic instruments.

Can Biomarkers Correctly Predict Ventilator-associated Pneumonia in Patients Treated With Targeted Temperature Management After Cardiac Arrest? An Exploratory Study of the Multicenter Randomized Antibiotic (ANTHARTIC) Study.

Ventilator-associated pneumonia (VAP) frequently occurs in patients with cardiac arrest. Diagnosis of VAP after cardiac arrest remains challenging, while the use of current biomarkers such as C-reactive protein (CRP) or procalcitonin (PCT) is debated. To evaluate biomarkers' impact in helping VAP diagnosis after cardiac arrest. This is a prospective ancillary study of the randomized, multicenter, double-blind placebo-controlled ANtibiotherapy during Therapeutic HypothermiA to pRevenT Infectious Complications (ANTHARTIC) trial evaluating the impact of antibiotic prophylaxis to prevent VAP in out-of-hospital patients with cardiac arrest secondary to shockable rhythm and treated with therapeutic hypothermia. An adjudication committee blindly evaluated VAP according to predefined clinical, radiologic, and microbiological criteria. All patients with available biomarker(s), sample(s), and consent approval were included. The main endpoint was to evaluate the ability of biomarkers to correctly diagnose and predict VAP within 48 hours after sampling. The secondary endpoint was to study the combination of two biomarkers in discriminating VAP. Blood samples were collected at baseline on day 3. Routine and exploratory panel of inflammatory biomarkers measurements were blindly performed. Analyses were adjusted on the randomization group. Among 161 patients of the ANTHARTIC trial with available biological sample(s), patients with VAP (n = 33) had higher body mass index and Acute Physiology and Chronic Health Evaluation II score, more unwitnessed cardiac arrest, more catecholamines, and experienced more prolonged therapeutic hypothermia duration than patients without VAP (n = 121). In univariate analyses, biomarkers significantly associated with VAP and showing an area under the curve (AUC) greater than 0.70 were CRP (AUC = 0.76), interleukin (IL) 17A and 17C (IL17C) (0.74), macrophage colony-stimulating factor 1 (0.73), PCT (0.72), and vascular endothelial growth factor A (VEGF-A) (0.71). Multivariate analysis combining novel biomarkers revealed several pairs with p value of less than 0.001 and odds ratio greater than 1: VEGF-A + IL12 subunit beta (IL12B), Fms-related tyrosine kinase 3 ligands (Flt3L) + C-C chemokine 20 (CCL20), Flt3L + IL17A, Flt3L + IL6, STAM-binding protein (STAMBP) + CCL20, STAMBP + IL6, CCL20 + 4EBP1, CCL20 + caspase-8 (CASP8), IL6 + 4EBP1, and IL6 + CASP8. Best AUCs were observed for CRP + IL6 (0.79), CRP + CCL20 (0.78), CRP + IL17A, and CRP + IL17C. Our exploratory study shows that specific biomarkers, especially CRP combined with IL6, could help to better diagnose or predict early VAP occurrence in cardiac arrest patients.

An Improved Algorithm for the Detection of Ventilator Associated Pneumonia

Background: Ventilator associated pneumonia (VAP) is associated with significant rates of morbidity and all-cause mortality. Active VAP surveillance can identify risk factors for which targeted preventive measures can be implemented. However, surveillance efforts are complicated by challenges associated with accurate VAP diagnosis. We aimed to improve the accuracy and automation of existing VAP diagnostic algorithms to better identify patients at risk. Methods: The study was conducted at NYU Langone Health from June 2022 through December 2023. We created a semi-automated VAP surveillance system using the Centers for Disease Control &amp; Prevention (CDC) ventilator associated event (VAE) definition as a base framework (Figure 1). We modified this definition to include additional elements, such as having a sputum culture ordered within 48 hours of worsening oxygen status, regardless of culture result. Using this algorithm—followed by manual clinician reviews—we retrospectively assessed possible VAP cases to determine the ability of our surveillance system to correctly identify VAP. Results: Of the 123 possible VAP cases identified through our automated system, 75 (61%) were correctly diagnosed as VAP after clinical review. This reflects a rate of 1.5 infections per 1000 ventilation days across the system and 1.85 infections per 100 patients ventilated for greater than 2 days. Of the 48 remaining patients without VAP after clinical review, 25% (n=12) were characterized as having hospital-acquired pneumonia, 21% (n=10) as acute respiratory distress syndrome or infection at another site and 10% (n=5) as pulmonary embolism/infarction. Among all patients identified through this automated system (VAP and non-VAP), 53% experienced in-hospital death. Discussion: Our automated VAP surveillance algorithm identified 123 cases of potential VAP, 61% of which were consistent with a clinical diagnosis of VAP upon manual chart review. Our VAP rate of 1.5 infections per 1000 ventilation days was similar to published rates at other North American hospital systems. The high in-hospital mortality rate among these patients highlights the need for improved surveillance systems and earlier interventions to reduce the risk of VAP. There are several limitations to the CDC’s VAE definition, including its requirement of a positive microbiologic culture and focus on sputum quality. This potentially misses cases of culture-negative VAP in patients receiving antibiotics prior to sputum collection. Our goal is to continue to validate and improve our algorithm’s ability to correctly identify patients with clinical VAP, so that targeted prevention efforts can be focused upon the patients with the highest risk for poor outcomes.Disclosure: Madeline DiLorenzo: Stocks - Abbvie, Amgen Inc., Becton Dickinson, Biogen Inc., Bristol Myers and Squibb, CVS Health, Davita Inc., Elevance Health, Gilead, Henry Schein, Hologic Inc., Humana Inc., Jazz Pharmaceuticals, Laboratory Corp, Merck and Co., Quest Diagnostics, ResMed Inc., Teladoc Health, Vertex Pharmaceuticals, West Pharmaceuticals

A Bibliometric Analysis of the Role and Research Trending of Bronchoalveolar Lavage in the Diagnosis and Treatment of Ventilator-Associated Pneumonia.

Ventilator-associated pneumonia (VAP) is one of the most common complications in intensive care units (ICUs) and negatively affects patient outcomes. Despite its widespread use as a diagnostic and therapeutic measure, the application and effectiveness of bronchoalveolar lavage (BAL) in the management of VAP require further exploration. This study aimed to evaluate the research dynamics, major trends, and scientific networks of BAL in the diagnosis and treatment of VAP using bibliometric analysis. Literature from the Web of Science database on BAL for the diagnosis and treatment of VAP from 1990 to 2024 was screened and analyzed. Keyword co-occurrence, trend analysis, and citation burst analyses were conducted using CiteSpace to identify research hotspots, core authors, institutions, and countries, as well as the evolution of research domains. The bibliometric analysis included 968 publications. Trend analysis indicated growing interest in BAL techniques, particularly in the categories of RESPIRATORY SYSTEM (burst score: 27.82) and MEDICINE, RESEARCH, and EXPERIMENTAL (burst score: 7.41). The co-citation analysis highlighted influential authors in the field, such as Torres(burst score: 9.35), Croce (burst score: 5.86), and Meduri(burst score: 5.71). Keyword analysis results revealed core clusters in the treatment of VAP with BAL, including "nonbronchoscopic lavage" (silhouette value: 0.703), "ICU-acquired infection" (silhouette value: 0.7), and "ventilator-associated tracheobronchitis" (silhouette value: 0.637). Additionally, geographic analysis showed that North America and Europe dominated the research in this field. Recently, research trends regarding protected specimen brushes and quantitative culture techniques have emerged. This study found broad applications of BAL in VAP management, especially in improving diagnostic accuracy and treatment outcomes. Optimized strategies such as improvement of lavage techniques and multidisciplinary collaboration may emerge as potential research hotspots in the future.

Role of bronchoscopy in the management of patients with suspected or suffering from ventilator-associated pneumonia: A meta-analysis

BackgroundThe utility of bronchoscopy in the treatment of patients with ventilator-associated pneumonia (VAP) has been proposed, although prior research has yielded inconclusive findings. This systematic review and meta-analysis were conducted to examine the impact of bronchoscopy on mortality rates, duration of mechanical ventilation (MV), and length of stay in the intensive care unit (ICU) among patients with VAP. MethodsRelevant randomized controlled trials (RCTs) and cohort studies were acquired by conducting a comprehensive search in the PubMed, Embase, and Cochrane Library databases. To account for the potential heterogeneity, a random-effects model was utilized to combine the findings and incorporate its potential influence. ResultsEight RCTs and three cohort studies, including 3907 patients with highly suspected or clinically diagnosed VAP, were included. Compared to the controls, bronchoscopy use was not associated with a significant effect on all-cause mortality (relative risk [RR]: 0.81, 95 % confidence interval [CI]: 0.62 to 1.05, p = 0.12; I2 = 57 %). Subgroup analysis showed that bronchoscopy used for the microbiological diagnosis of VAP was not associated with reduced mortality (RR: 0.92, 95 % CI: 0.75 to 1.13), while therapeutic bronchoscopy use was associated with significantly reduced mortality (RR: 0.53, 95 % CI: 0.35 to 0.81). The duration of MV or length of ICU stay was not significantly different between groups. ConclusionsBronchoscopy use for the purpose of the microbiological diagnosis of VAP did not reduce short-term mortality compared to diagnosis without bronchoscopy use, while therapeutic bronchoscopy use was associated with reduced mortality in these patients.

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

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

Pathogenesis, Diagnosis and Therapeutic Strategies for Ventilator-associated Pneumonia

Ventilator-associated pneumonia (VAP) is a major health care associated infection which usually emanates from aspiration, immigration of pathogens from aerodigestive tract, adulterated appliance uses or medications. The mortality rate due to VAP is approximately 13% and the causative organisms are bacteria, viruses, and fungi. Many studies have investigated the causative organisms as Pseudomonas spp., Acinetobacter spp., Escherichia coli, Klebsiella pneumoniae, and Staphylococcus aureus with varying prevalence. Intensive Care Unit (ICU) admitted patients who are ventilated, are more prone to the infections where the pathogens adhere to the mucosa of lower respiratory tract of mechanically ventilated patients and start infections. Clinical diagnosis based on Clinical Pulmonary Infection Score (CPIS) has poor specificity and microbiological findings takes 48-72 hrs, that can delay the treatment of patients. Lymphopenia on complete blood count is a predictor of mortality in VAP patients, but decreased lymphocyte count occurs in various other infections too. Multiplex PCR is a better diagnostic technique for VAP which can even diagnose atypical bacteria along with other etiological agents. Effectively employing sampling techniques is a vital step in the diagnosis of VAP, enabling the identification of pathogens responsible for lung infections. Furthermore, the emergence of novel therapeutic options approved by regulatory bodies, adds significant advancements in VAP treatment. In this review article, we have performed an in-depth study on the pathogenesis, diagnosis and therapeutic strategies involved in VAP. This study will help the researchers working in this area to design their work appropriately with the updated knowledge on VAP.

Evolution of Tracheobronchial Colonization Following Tracheal Intubation in Patients With Neurologic Injury Who Are Ventilated: The INSPIRE Study

BackgroundCharacteristics and course of endotracheal secretions have scarcely been studied in patients under mechanical ventilation (MV) at risk of developing ventilator-associated pneumonia (VAP). Research questionExhaustive description of endotracheal secretions and determination of their predictive value for the diagnosis of VAP during MV. Study design and methodsSingle-center prospective study in neuro-injured patients requiring MV for at least 7 days. Patients with pulmonary and infectious diseases were ineligible. All endotracheal aspirates (ETA) collected between tracheal intubation and Day7 were analyzed. Macroscopic characteristics and microbiology were assessed. CPIS was calculated daily. A blinded adjudication committee validated all VAP events. ResultsForty-eight patients and 1544 ETAs were analyzed. Overall, 81% of the ETA were purulent and 50% were thick. Culture results showed high inter- and intra-individual variability. Ten patients (21%) developed an early VAP. Eight patients (80%) with VAP and 14 (37%) without had a CPIS>6. The day before VAP diagnosis, a 20-mL increase in ETA volume detected a VAP with a sensitivity of 67% and a specificity of 93%. InterpretationOur study provides new information on the course of respiratory colonization in mechanically ventilated patients and suggests that ETA color and aspect, and pathogens kinetics cannot predict VAP. Traditional VAP criteria (CPIS and bacterial load) had also a low diagnostic specificity. Contrariwise, an increase in secretion volume should alert for VAP development.