Prophylactic antibiotics in adults with acute brain injury who are invasively ventilated in the Intensive Care Unit: A systematic review and meta-analysis.

BACKGROUND: Lower respiratory tract infections are common in patients receiving invasive mechanical ventilation in an Intensive Care Unit (ICU) after an acute brain injury and may have deleterious consequences. RESEARCH QUESTION: In adults with acute brain injury receiving invasive mechanical ventilation in an ICU, is the administration of prophylactic parenteral antibiotics, compared to placebo or usual care, associated with reduced mortality? STUDY DESIGN AND METHODS: We conducted a systematic review and meta-analysis. We searched for randomised clinical trials (RCTs) in electronic databases, as well as unpublished trials. The primary outcome was hospital mortality, secondary outcomes included the incidence of ventilator associated pneumonia, ICU length of stay, and duration of mechanical ventilation. We used a random effects model to estimate the pooled risk ratio (RR) with corresponding 95% confidence intervals (CI) for binary outcomes and the mean difference (MD) with 95% CI for continuous outcomes. Certainty of evidence was evaluated using GRADE methods. RESULTS: There were 1728 reports of studies screened, with 7 RCTs recruiting 835 participants included. No trials were adjudicated as having a high risk of bias. The pooled estimated risk ratio (RR) for mortality associated with the use of prophylactic antibiotics was 0.91 (95% CI 0.70 to 1.17, p=0.39, low certainty). The pooled estimated RR for ventilator associated pneumonia was 0.56 (95% CI 0.35 to 0.89, low certainty). The pooled estimated duration of mechanical ventilation for those allocated to prophylactic antibiotics compared to control (mean difference (MD) -2.0 days, 95% CI -6.1 to 2.1, very low certainty) and duration of ICU admission (MD -2.2 days, 95% CI -5.4 to 1.1 days, very low certainty) were similar. INTERPRETATION: Current evidence from randomised clinical trials does not provide definitive evidence regarding the effect of prophylactic antibiotics on mortality in patients receiving invasive mechanical ventilation in the ICU.

Effects of Candida colonization on patients with ventilator-associated pneumonia and pathogenic microorganisms: Systematic review and meta-analysis.

BACKGROUND: In the intensive care unit (ICU), patients undergoing mechanical ventilation (MV) often exhibit Candida colonization. This study aims to systematically review and analyze the effects of Candida colonization on the outcomes of mechanically ventilated patients and its relationship with bacterial pathogens associated with ventilator-associated pneumonia (VAP). METHODS: We conducted a comprehensive search across PubMed, Embase, Web of Science (WOS), and the Cochrane Central Register of Controlled Trials (CENTRAL) without language restrictions to identify eligible studies. Inclusion criteria involved patients undergoing MV for >2 days, encompassing those with clinically suspected VAP (csVAP), and confirmed VAP patients. We assessed the impact of Candida colonization on patient prognosis, length of ICU stay, bacterial pathogens responsible for VAP, and inflammatory markers. The study protocol was registered with PROSPER (CRD42024580547). RESULTS: Thirteen studies involving 3,802 patients were included in our analysis. The prevalence of Candida colonization among MV patients ranged from 10 % to 56 %. Our findings indicated that Candida airway colonization was associated with poorer patient prognosis (95 % CI 1.13-1.52, p < 0.05, I² = 39 %). Among patients who developed VAP, Candida colonization correlated with increased detection rates of Pseudomonas aeruginosa (RR = 1.37, 95 % CI 1.07-1.75, p = 0.01, I² = 3 %) and Acinetobacter baumannii (RR= 1.48, 95 % CI 1.17-1.86, p < 0.01, I² = 27 %). Additionally, an association with antibiotic resistance was observed, although the quality of evidence was low. In studies that recorded patients' inflammatory markers, no significant effect of Candida colonization on inflammatory markers (procalcitonin, interleukin-6) was observed. CONCLUSION: Candida airway colonization is highly prevalent among mechanically ventilated patients and should be considered a marker of poor prognosis when it occurs. Antibiotics should be used more carefully when Candida colonization is detected in the respiratory tract of mechanically ventilated patients.

Fiberoptic bronchoscopy for the prevention of ventilator-associated pneumonia: a meta-analysis of randomized controlled trials.

INTRODUCTION: Ventilator-associated pneumonia (VAP) causes increased time of mechanical ventilation (MV), prolonged intensive care unit (ICU) stay, and a higher mortality risk. The systematic review and meta-analysis aimed to compare the efficacies between fiberoptic bronchoscopy (FOB) and general sputum suction for the prevention of VAP in patients with invasive MV. METHODOLOGY: Relevant randomized controlled trials (RCTs) were obtained via a search of PubMed, Embase, Cochrane Library, Wanfang, and CNKI databases. A random-effects model was used to pool the results if significant heterogeneity was observed. Otherwise, a fixed-effects model was used. RESULTS: Sixteen RCTs were included. Compared to general sputum suction, sputum suction with FOB was associated with a significantly reduced risk of VAP (risk ratio [RR]: 0.56, 95% CI: 0.47 to 0.67, p < 0.001; I2 = 0%). Subgroup analyses showed that the combination of FOB-assisted sputum suction with bronchoalveolar lavage (BAL) further reduced the risk of VAP as compared to FOB-assisted sputum suction alone (p for subgroup difference = 0.04). In addition, FOB-assisted treatment was also associated with a reduced MV time (mean difference [MD]: -2.19 days, 95% CI: -2.69 to -1.68, p < 0.001; I2 = 18%), a shorter ICU stay (MD: 2.9 days, 95% CI: -3.68 to -2.13, p < 0.001; I2 = 34%), and a reduced mortality risk (RR: 0.46, 95% CI: 0.24 to 0.90, p = 0.02; I2 = 0%) in patients with invasive MV. CONCLUSIONS: FOB for sputum suction and BAL in patients with invasive MV is effective in reducing the incidence of VAP.

A Retrospective Closed Cohort Study on Distribution of Multidrug-Resistant Bacteria in Ventilator-Associated Pneumonia and its Impact on Patient Outcome.

OBJECTIVES: Ventilator-associated pneumonia (VAP) is a common and serious nosocomial infection affecting critically ill patients undergoing mechanical ventilation. This study investigated the prevalence of multidrug-resistant (MDR) organisms in VAP, the VAP rate, and the outcomes associated with MDR-VAP. METHODS: This retrospective single-center study, conducted in 2022, included adult ICU cases from April 2021 to March 2022, receiving mechanical ventilation for more than 48 h. Patient data were analyzed for demographics, comorbidities, empirical antibiotic use, and outcomes. MDR organisms were identified in respiratory cultures. RESULTS: Among 447 patients, 133 developed VAP, with 96 cases being MDR-VAP. The mean age of the overall VAP population was 52 years, 70% of which were males. The incidence of VAP was 30.0% (95% CI: 25.7%-34.5%), while that of MDR-VAP was 21.6% (95% CI: 17.9%-25.8%). The most prevalent MDR organisms were Acinetobacter species (50%) and Klebsiella pneumoniae (46.9%). Empirical antibiotics were administered in 96% of VAP cases. The overall VAP rate was 38.03/1000 ventilator days. No single antimicrobial agent seemed to offer an empirical cover, as the susceptibility rate for most tested antimicrobials was less than 85%. Patients with MDR-VAP had a low survival rate (64.6%) and were less likely to be extubated at 13.5% compared to non-MDR-VAP (survival rate of 62.2%). COVID-19 patients had a high incidence of MDR VAP, especially with Acinetobacter. Overall, VAP mortality was 57.1%. The median ventilator days were 16 for VAP and only four for non-VAP. CONCLUSION: Gram-negative organisms, particularly Klebsiella and Acinetobacter, were the main MDR VAP culprits. MDR-VAP exhibited higher morbidity and mortality. A study focused on developing resistance by microorganisms is warranted for further understanding.

Prevalence and risk factors for ventilator-associated pneumonia after cardiac surgery: a systematic review and meta-analysis.

Background: There is currently significant variation in the reported incidence of ventilator-associated pneumonia (VAP) among postoperative cardiac patients. Moreover, the risk factors for VAP in postoperative cardiac patients remain controversial. This study aims to assess the incidence and risk factors of VAP in postoperative cardiac patients to provide a basis for further prevention and treatment of VAP. Methods: We systematically reviewed PubMed, EMBASE, and Cochrane Library databases to select studies that met the inclusion criteria until November 2023. Results: Fifteen studies involving 10,478 patients who underwent cardiac surgery were selected for meta-analysis. The incidence of VAP in postoperative cardiac patients was 10%. The preoperative risk factors for VAP after cardiac surgery included age >70 years, chronic obstructive pulmonary disease (COPD), peripheral vascular disease, renal disease, and severe pulmonary hypertension. Furthermore, the perioperative risk factors for VAP after cardiac surgery included emergency surgery, redo surgery, airway instrumentation, gastric aspiration, reintubation, mechanical ventilation duration >3 days, intra-aortic balloon, New York Heart Association >3, American Society of Anesthesiologists >3, need for transfusion during surgery, and ascending aortic surgery. Conclusions: The incidence of VAP after cardiac surgery was found to be 10%, and the comprehensive risk factors for VAP were identified, emphasizing the critical need for targeted interventions, including optimization of preoperative health and refined surgical protocols, to effectively reduce the occurrence of VAP in postoperative cardiac patients.

Incidence and risk factors of ventilator-associated pneumonia in the intensive care unit: a systematic review and meta-analysis.

Background: Ventilator-associated pneumonia (VAP) is a serious complication occurring in critically ill patients receiving mechanical ventilation in the intensive care unit (ICU). This study attempted to analyze VAP incidence in the ICU using a meta-analysis, investigate risk factors for VAP occurrence, and examine influence of VAP on outcomes. Methods: A search was carried out in the Web of Science, PubMed, Embase, and The Cochrane Library databases to identify studies on incidence and risk factors of VAP in ICU patients. Study quality was tested by the Newcastle-Ottawa Scale. Data related to risk factors, incidence, and outcomes were utilized for meta-analysis. Meta-analysis was conducted using Stata 18 and Review Manager 5.4. Results: Seventeen articles were included, comprising 6,222 patients, and incidence of VAP was 30% [95% confidence interval (CI): 24-37%]. Risk factor analysis showed that males [odds ratio (OR): 1.50; 95% CI: 1.29-1.75; P<0.001], smoking (OR: 1.30; 95% CI: 1.08-1.57; P=0.007) and Acute Physiology and Chronic Health Evaluation II (APACHE II) score [weighted mean difference (WMD): 1.30; 95% CI: 0.31-2.30; P=0.01] were risk factors for VAP. Antibiotic prophylaxis (OR: 0.79; 95% CI: 0.63-0.99; P=0.04) was a protect factor for VAP. Compared with non-VAP patients, VAP patients had a prolonged duration of mechanical ventilation (WMD: 6.96; 95% CI: 5.42-8.50; P<0.001), ICU length of stay (WMD: 7.91; 95% CI: 5.43-10.39; P<0.001) and total length of hospital stay (WMD: 8.09; 95% CI: 3.70-12.48; P=0.0003). There was no significant difference in mortality rate between VAP and non-VAP patients (OR: 1.13; 95% CI: 0.79-1.63; P=0.50). Conclusions: VAP incidence in the ICU was around 30%. Male, smoking, and high APACHE II score were risk factors for VAP, while antibiotic prophylaxis was a protective factor for VAP. VAP could lead to prolonged mechanical ventilation, ICU stay, and hospital stay, but it did not influence mortality.

Construction of Survival Nomogram for Ventilator-Associated Pneumonia Patients: Based on MIMIC Database.

Objective: To construct and validate a predictive nomogram model for the survival of patients with ventilator-associated pneumonia (VAP) to enhance prediction of 28-day survival rate in critically ill patients with VAP. Methods: A total of 1,438 intensive care unit (ICU) patients with VAP were screened through Medical Information Mart for Intensive Care (MIMIC)-IV. On the basis of multi-variable Cox regression analysis data, nomogram performance in predicting survival status of patients with VAP at ICU admission for 7, 14, and 28 days was evaluated using the C-index and area under the curve (AUC). Calibration and decision curve analysis curves were generated to assess clinical value and effectiveness of model, and risk stratification was performed for patients with VAP. Result: Through stepwise regression screening of uni-variable and multi-variable Cox regression models, independent prognostic factors for predicting nomogram were determined, including age, race, body temperature, Sequential Organ Failure Assessment score, anion gap, bicarbonate concentration, partial pressure of carbon dioxide, mean corpuscular hemoglobin, and liver disease. The model had C-index values of 0.748 and 0.628 in the train and test sets, respectively. The receiver operating characteristic curve showed that nomogram had better performance in predicting 28-day survival status in the train set (AUC = 0.74), whereas it decreased in the test set (AUC = 0.66). Calibration and decision curve analysis curve results suggested that nomogram had favorable predictive performance and clinical efficacy. Kaplan-Meier curves showed significant differences in survival between low, medium, and high-risk groups in the total set and training set (log-rank p < 0.05), further validating the effectiveness of the model. Conclusion: The VAP patient admission ICU 7, 14, and 28-day survival prediction nomogram was constructed, contributing to risk stratification and decision-making for such patients. The model is expected to play a positive role in supporting personalized treatment and management of VAP.

Tissue-Compatible and Lubricated Hydrogel Catheter with Promising Activity Against Polymicrobial Infections for Ventilator-Associated Pneumonia Prevention.

Endotracheal intubation is a vital means of saving critically ill patients. However, the inserted catheter often causes tissue damage and the formation of tenacious biofilms containing drug-resistant bacteria and fungi, leading to severe ventilator-associated pneumonia (VAP). Currently, the resolution of VAP is usually based on antibiotic treatment and lacks targeted prophylaxis. Here, a quaternary phosphonium salts functionalized hydrogel catheter that enhances tissue compatibility yet inhibits complex and tenacious pathogens in the catheter, thus preventing VAP is reported. By copolymerizing the quaternary phosphonium electrolyte and acrylic acid monomers, the hydrogel catheter demonstrates good shape-supporting ability, and its strength and modulus can be adjusted over a wide range to meet the needs of different ages. Moreover, it possesses good tissue compatibility, antifouling properties, stable lubrication capability, and superior hydrophilicity, which may mitigate tissue damage caused by contact. Importantly, the hydrogel catheter demonstrates potent broad-spectrum intrinsic antimicrobial activity, eradicating nearly 99% of multi-drug resistant bacteria and 80% of fungi. To validate its role in preventing VAP, the real VAP pathogenesis process is mimicked, establishing a polymicrobial infections model considering time effects. The results prove that the hydrogel catheter effectively inhibits the invasion of various drug-resistant pathogens and prevents biofilm formation.

Polymyxin B Peptide Hydrogel Coating: A Novel Approach to Prevent Ventilator-Associated Pneumonia.

Ventilator-associated pneumonia (VAP) remains one of the most common hospital-acquired infections (HAI). Considering the complicated diagnosis and the lack of effective treatment, prophylactic measures are suggested as the new standard to prevent the disease. Although VAP often manifests a polymicrobial nature, Pseudomonas aeruginosa remains one of the pathogens associated with the highest morbidity and mortality rates within these mechanically ventilated patients. In this paper, we report on the development of an antibacterial hydrogel coating using the polymyxin B (PMB) peptide to prevent bacterial adhesion to the polymeric substrate. We fully characterized the properties of the coating using atomic force microscopy (AFM), scanning electron microscopy (SEM), wettability analyses and Fourier-transform infrared (FTIR) and Raman spectroscopy. Furthermore, several biological assays confirmed the antibacterial and anti-biofilm effect of the tubing for at least 8 days against P. aeruginosa. On top of that, the produced coating is compliant with the requirements regarding cytocompatibility stated in the ISO (International Organization for Standardization) 10993 guidelines and an extended release of PMB over a period of at least 42 days was detected. In conclusion, this study serves as a foundation for peptide-releasing hydrogel formulas in the prevention of VAP.

Predicting nosocomial pneumonia risk in level-1 trauma patients: An external validation study using the trauma quality improvement program.

BACKGROUND: Early identification of patients at risk of nosocomial pneumonia enables the opportunity for preventative measures, which may improve survival and reduce costs. Therefore, this study aimed to externally validate an existing prediction model (issued by Croce et al.) to predict nosocomial pneumonia in patients admitted to US level-1 trauma centers. METHODS: A retrospective cohort study including patients admitted to level-1 trauma centers and registered in the TQIP, a US nationwide trauma registry, admitted between 2013-2015 and 2017-2019. The main outcome was total nosocomial pneumonia for the first period and ventilator-associated pneumonia (VAP) for the second. Model discrimination and calibration were assessed before and after recalibration. RESULTS: The study comprised 902,231 trauma patients (N2013-2015 â€‹= â€‹180,601; N2017-2019 â€‹= â€‹721,630), with a median age of 52 in both periods, 64-65 â€‹% male, and approximately 90 â€‹% sustaining blunt traumatic injury. The median Injury Severity Scores were 13 (2013-2015) versus 9 (2017-2019); median Glasgow Coma Scale scores were 15. Nosocomial pneumonia incidence was 4.4 â€‹%, VAP incidence was 0.7 â€‹%. The original model demonstrated good to excellent discrimination for both periods (c-statistic2013-2015 0.84, 95%CI 0.83-0.84; c-statistic2017-2019 0.92, 95%CI 0.91-0.92). After recalibration, discriminatory capacity and calibration for the lower predicted probabilities improved. CONCLUSIONS: The Croce model can identify patients admitted to US level-1 trauma centers at risk of total nosocomial pneumonia and VAP. Implementing (modified) Croce models in route trauma clinical practice could guide judicious use of preventative measures and prescription of additional non-invasive preventative measures (e.g., increased monitoring, pulmonary physiotherapy) to decrease the occurrence of nosocomial pneumonia in at-risk patients.

Korean Guidelines for the Management and Antibiotic Therapy in Adult Patients with Hospital-Acquired Pneumonia.

BACKGROUND: Hospital-acquired pneumonia (HAP) and ventilator-associated pneumonia (VAP) are correlated with high morbidity and mortality rates. Guidelines that consider local epidemiologic data are fundamental for identifying optimal treatment strategies. However, Korea has no HAP/VAP guidelines. METHODS: This study was conducted by a committee of nine experts from the Korean Academy of Tuberculosis and Respiratory Diseases Respiratory Infection Study Group using the results of Korean HAP/VAP epidemiologic studies. Eleven key questions for HAP/VAP diagnosis and treatment were addressed. The Convergence of Opinion on Suggestions and Evidence (CORE) process was used to derive suggestions, and evidence levels and recommendation grades were in accordance with the Grading of Recommendations Assessment Development and Evaluation (GRADE) methodology. RESULTS: Suggestions were made for the 11 key questions pertinent to diagnosis, biomarkers, antibiotics, and treatment strategies for adult patients with HAP/VAP. CONCLUSION: Using the CORE process and GRADE methodology, the committee generated a series of recommendations for HAP/VAP diagnosis and treatment in the Korean context.

Optimizing Diagnosis and Management of Ventilator-Associated Pneumonia: A Systematic Evaluation of Biofilm Detection Methods and Bacterial Colonization on Endotracheal Tubes.

Healthcare-associated infections, such as ventilator-associated pneumonia and biofilm formation on intubation cannulas, impose significant burdens on hospitals, affecting staffing, finances, and patient wellbeing, while also increasing the risk of patient mortality. We propose a research study aimed at exploring various methodologies for detecting these infections, discovered in the biofilm on medical devices, particularly tracheal cannulas, and understanding the role of each method in comprehending these infections from an etiological perspective. Our investigation also involves an analysis of the types of endotracheal tubes utilized in each case, the bacteria species identified, and strategies for combating biofilm-associated infections. The potential impact of our research is the substantial improvement of patient care through enhanced diagnosis and management of these infections.

Intravenous combined with aerosolised polymyxins versus intravenous polymyxins monotherapy for ventilator-associated pneumonia: a systematic review and meta-analysis.

Polymyxins was applied to treat ventilator associated pneumonia (VAP) caused by carbapenem-resistant Gram-negative bacteria (CR-GNB) via different administration routes. The potential benefits of aerosolised polymyxins as adjunctive treatment for patients still were contradictory. This review assessed the safety and efficacy of intravenous combined with aerosolised polymyxins versus intravenous polymyxins monotherapy in patients with VAP caused by CR-GNB. Two reviewers independently evaluated and extracted date from Pubmed, Embase, Cochrane library and Web of science. The primary outcome was all-cause mortality and secondary outcomes included clinical cure rate, clinical improvement rate, microbiological eradication and nephrotoxicity. Differences for dichotomous outcomes were expressed as odds ratios (OR) with 95% confidence intervals (CI). Eleven eligible studies were included. The results showed that compared with intravenous polymyxins monotherapy, intravenous plus aerosolised polymyxins therapy significantly reduced all-cause mortality rate (OR = 0.75, 95% CI 0.57 - 0.99, P = 0.045) and improved clinical improvement rate (OR = 1.62, 95% CI 1.02 - 2.60, P = 0.043) and microbial eradication rate (OR = 2.07, 95% CI 1.40 - 3.05, P = 0.000). However, there were no significant difference in terms of clinical cure rate (OR = 1.59, 95% CI 0.96 - 2.63, P = 0.072) and nephrotoxicity (OR = 1.14, 95% CI 0.80 - 1.63, P = 0.467) for intravenous plus aerosolised polymyxins therapy. Subgroup analysis revealed that the clinical improvement rate was improved significantly in case-control studies. Aerosolised polymyxins maybe a useful adjunct to intravenous polymyxins for CR-GNB VAP patients.

Inverse probability weighting leads to more accurate incidence estimates for healthcare associated infections in intensive care units, results from two national surveillance systems.

BACKGROUND: Two main approaches are employed to monitor healthcare associated infections (HAIs): longitudinal surveillance, which allows to measure incidence rates, and point prevalence surveys (PPS). PPS are less time-consuming; however, they are affected by length-biased sampling, which can be corrected through inverse probability weighting. We assessed the accuracy of this method by analysing data from two Italian national surveillance systems. METHODS: Ventilator associated pneumonia (VAP) and central-line associated bloodstream infection (CLABSI) incidence measured through a prospective surveillance system (GiViTI) was compared to incidence estimates obtained through conversion of crude and inverse probability weighted prevalence of the same HAIs in intensive care units (ICUs) measured through a PPS. Weighted prevalence rates were obtained after weighting all patients inversely proportional to their time-at-risk. Prevalence rates were converted into incidence per 100 admissions using an adapted version of the Rhame and Sudderth formula. RESULTS: Overall, 30988 patients monitored through GiViTI, and 1435 patients monitored through the PPS were included. A significant difference was found between incidence rates estimated based on crude VAP and CLABSI prevalence and measured through GiViTI (relative risk, RR 2.5 and 3.36; 95% confidence interval, CI 1.42 - 4.39 and 1.33 - 8.53, p = 0.006 and 0.05 respectively). Conversely, no significant difference was found between incidence rates estimated based on weighted VAP and CLABSI prevalence and measured through GiViTI (p = 0.927 and 0.503 respectively). CONCLUSION: When prospective surveillance is not feasible, our simple method could be useful to obtain more accurate incidence rates from PPS data.

Impact of head-of-bed elevation angle on the development of pressure ulcers and pneumonia in patients on mechanical ventilation: a systematic review and meta-analysis.

BACKGROUND: Mechanical ventilation is crucial for patient management in intensive care units, but it comes with complications such as pressure ulcers and ventilator-associated pneumonia (VAP). The impact of head-of-bed elevation angles on these complications remains a critical area for investigation. METHODS: This systematic review and meta-analysis followed PRISMA guidelines and involved searches across PubMed, Embase, Web of Science, and Cochrane Library, conducted on September 19, 2023, with no date or language restrictions. We included randomized controlled trials that compared different head-of-bed elevation angles in adult ICU patients on mechanical ventilation. Data were extracted on study characteristics, quality assessed using the Cochrane risk of bias tool, and statistical analyses performed using chi-square tests for heterogeneity and fixed or random-effects models based on heterogeneity results. RESULTS: Six studies met inclusion criteria out of an initial 601 articles. These studies showed minimal heterogeneity (I2 = 0.0% for pressure ulcers, p = 0.930; and for VAP, p = 0.797), supporting the use of fixed-effect models. Results indicated that a higher elevation angle (45°) significantly increased the risk of pressure ulcers (OR = 1.95, 95% CI: 1.12-3.37, p < 0.05) and decreased the incidence of VAP compared to a lower angle (30°) (OR = 0.51, 95% CI: 0.31-0.84, p < 0.05). CONCLUSIONS: While higher head-of-bed elevation can reduce the risk of VAP in mechanically ventilated patients, it may increase the risk of pressure ulcers. Clinical strategies should carefully balance these outcomes to optimize patient care in ICU settings. REGISTRATION: PROSPERO 2024 CRD42024570232.

Predictive values of serum amyloid A, toll-like receptor 4, and sTREM-1 for ventilator-associated pneumonia in elderly patients undergoing abdominal surgery with tracheal intubation and general anesthesia.

OBJECTIVES: This study aimed to conduct a retrospective study to identify inflammatory biomarkers for predicting ventilator-associated pneumonia in elderly patients. METHODS: Our retrospective study included 265 elderly patients (age ≥60 years) undergoing abdominal surgery with tracheal intubation and general anesthesia, with 93 experiencing varying degrees of ventilator-associated pneumonia during hospitalization, and 172 without. Serum concentrations of serum amyloid A (SAA), toll-like receptor 4 (TLR4), and soluble myeloid triggering receptor 1 (sTREM-1) were measured at 24 h post-operation using enzyme-linked immunosorbent assay. Comparisons of SAA, TLR4, and sTREM-1 and other risk factors at 24 h post-operation between elderly patients with and without ventilator-associated pneumonia were performed. RESULTS: The study revealed a 35.1% incidence of postoperative ventilator-associated pneumonia among elderly patients. Upregulations of SAA, TLR4, and sTREM-1 were observed in patients with ventilator-associated pneumonia. Chronic obstructive pulmonary disease, smoking, and tracheal intubation were identified as independent risk factors. The joint prediction model was demonstrated with superior predictive accuracy (area under the curve = 0.89) compared to individual biomarkers. Correlations with procalcitonin further supported the predictive potential of SAA, TLR4, and sTREM-1 in an inflammatory response. CONCLUSIONS: SAA, TLR4, and sTREM-1, particularly when combined, serve as valuable prognostic indicators for postoperative ventilator-associated pneumonia in elderly patients undergoing abdominal surgery with tracheal intubation and general anesthesia. The joint prediction model offered a promising tool for early risk assessment.

Bacterial co-infection in COVID-19: a call to stay vigilant.

Co-infection with diverse bacteria is commonly seen in patients infected with the novel coronavirus, SARS-CoV-2. This type of co-infection significantly impacts the occurrence and development of novel coronavirus infection. Bacterial co-pathogens are typically identified in the respiratory system and blood culture, which complicates the diagnosis, treatment, and prognosis of COVID-19, and even exacerbates the severity of disease symptoms and increases mortality rates. However, the status and impact of bacterial co-infections during the COVID-19 pandemic have not been properly studied. Recently, the amount of literature on the co-infection of SARS-CoV-2 and bacteria has gradually increased, enabling a comprehensive discussion on this type of co-infection. In this study, we focus on bacterial infections in the respiratory system and blood of patients with COVID-19 because these infection types significantly affect the severity and mortality of COVID-19. Furthermore, the progression of COVID-19 has markedly elevated the antimicrobial resistance among specific bacteria, such as Klebsiella pneumoniae, in clinical settings including intensive care units (ICUs). Grasping these resistance patterns is pivotal for the optimal utilization and stewardship of antibiotics, including fluoroquinolones. Our study offers insights into these aspects and serves as a fundamental basis for devising effective therapeutic strategies. We primarily sourced our articles from PubMed, ScienceDirect, Scopus, and Google Scholar. We queried these databases using specific search terms related to COVID-19 and its co-infections with bacteria or fungi, and selectively chose relevant articles for inclusion in our review.

Metagenomics in the Diagnosis of Pneumonia: Protocol for a Systematic Review.

BACKGROUND: Causative pathogens are currently identified in only a minority of pneumonia cases, which affects antimicrobial stewardship. Metagenomic next-generation sequencing (mNGS) has potential to enhance pathogen detection due to its sensitivity and broad applicability. However, while studies have shown improved sensitivity compared with conventional microbiological methods for pneumonia diagnosis, it remains unclear whether this can translate into clinical benefit. Most existing studies focus on patients who are ventilated, readily allowing for analysis of bronchoalveolar lavage fluid (BALF). The impact of sample type on the use of metagenomic analysis remains poorly defined. Similarly, previous studies rarely differentiate between the types of pneumonia involved-community-acquired pneumonia (CAP), hospital-acquired pneumonia (HAP), or ventilator-associated pneumonia (VAP)-which have different clinical profiles. OBJECTIVE: This study aims to determine the clinical use of mNGS in CAP, HAP, and VAP, compared with traditional microbiological methods. METHODS: We aim to review all studies (excluding case reports of a series of fewer than 10 people) of adult patients with suspected or confirmed pneumonia that compare metagenomic analysis with traditional microbiology techniques, including culture, antigen-based testing, and polymerase chain reaction-based assays. Relevant studies will be identified through systematic searches of the Embase, MEDLINE, Scopus, and Cochrane CENTRAL databases. Screening of titles, abstracts, and subsequent review of eligible full texts will be done by 2 separate reviewers (SQ and 1 of AL, CJ, or CH), with a third clinician (ES) providing adjudication in case of disagreement. Our focus is on the clinical use of metagenomics for patients with CAP, HAP, and VAP. Data extracted will focus on clinically important outcomes-pathogen positivity rate, laboratory turnaround time, impact on clinical decision-making, length of stay, and 30-day mortality. Subgroup analyses will be performed based on the type of pneumonia (CAP, HAP, or VAP) and sample type used. The risk of bias will be assessed using the QUADAS-2 tool for diagnostic accuracy studies. Outcome data will be combined in a random-effects meta-analysis, and where this is not possible, a narrative synthesis will be undertaken. RESULTS: The searches were completed with the assistance of a medical librarian on January 13, 2024, returning 5750 records. Screening and data extraction are anticipated to be completed by September 2024. CONCLUSIONS: Despite significant promise, the impact of metagenomic analysis on clinical pathways remains unclear. Furthermore, it is unclear whether the use of this technique will alter depending on whether the pneumonia is a CAP, HAP, or VAP or the sample type that is collected. This systematic review will assess the current evidence base to support the benefit of clinical outcomes for metagenomic analysis, depending on the setting of pneumonia diagnosis or specimen type used. It will identify areas where further research is needed to advance this methodology into routine care. TRIAL REGISTRATION: PROSPERO CRD42023488096; https://tinyurl.com/3suy7cma. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/57334.