A Systematic Review and Meta-analysis of Ventilator-associated Pneumonia in Adults in Asia: An Analysis of National Income Level on Incidence and Etiology

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

Background

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

Methods

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

Findings

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

Interpretation

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

Funding

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

Ventilator-associated pneumonia: pathobiological heterogeneity and diagnostic challenges

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

Profile of patients in private home care who developed ventilator-associated pneumonia

OBJECTIVES

to analyze the profile and clinical outcomes of patients who developed Ventilator-Associated Pneumonia (VAP) in private home care and to compare the incidence with national data.

METHODS

this was a retrospective study with data collected from July 2021 to June 2022 from patient records at a private clinic. Patients using intermittent ventilation or without ventilatory support were excluded.

RESULTS

the utilization rate of mechanical ventilation was 15.9%. The incidence density of pneumonia in pediatrics was 2.2 cases per 1000 ventilation-days and in adults was 1.7 cases per 1000 ventilation-days, figures lower than those reported by the National Health Surveillance Agency. There were 101 episodes of pneumonia in 73 patients, predominantly male (65.8%), adults (53.4%), and those with neurological diseases (57.5%). The treatment regimen predominantly took place at home (80.2%), and there was one death.

CONCLUSIONS

patients in home care showed a low incidence and mortality rate from ventilator-associated pneumonia.

Improving Outcomes in Nosocomial Pneumonia: Recent Evidence and More Challenges

Nosocomial pneumonia (NP) represents a leading nosocomial infection and results in substantial morbidity and cost. Over the last several years, the evidence has evolved which directs our approach to NP. Specifically, the definition of NP and classification of its various subtypes has expanded to capture nuances among various phenotypes of this syndrome. For example, segregating those with hospital-acquired pneumonia (HAP) based on whether they subsequently require mechanical ventilation has been shown to be important. Likewise, newer data indicate the true economic cost of NP and underscore the diverse range of pathogens that can cause NP. Moreover, multidrug-resistant (MDR) bacteria have become a major threat in NP. Fortunately, newer simple preventive strategies have been tested and found to be effective at reducing the incidence of NP. Should prevention fail, a range of new antibiotics have been formally studied in NP and found to be effective. Some of these novel agents have relatively broad ranges of activity and are in vitro active against select MDR organisms. Others, however, are narrower in spectrum and directed against specific problem bacteria. In short, the literature in the field of NP has progressed rapidly, and clinicians require a clear appreciation of these changes so as to improve patient outcomes.

A nomogram predicting pneumonia after cardiac surgery: a retrospective modeling study

BACKGROUND

Postoperative pneumonia (POP) is the most prevalent of all nosocomial infections in patients who underwent cardiac surgery. The aim of this study was to identify independent risk factors for pneumonia after cardiac surgery, from which we constructed a nomogram for prediction.

METHODS

The clinical data of patients admitted to the Department of Cardiothoracic Surgery of Nanjing Drum Tower Hospital from October 2020 to September 2021 who underwent cardiac surgery were retrospectively analyzed, and the patients were divided into two groups according to whether they had POP: POP group (n=105) and non-POP group (n=1083). Preoperative, intraoperative, and postoperative indicators were collected and analyzed. Logistic regression was used to identify independent risk factors for POP in patients who underwent cardiac surgery. We constructed a nomogram based on these independent risk factors. Model discrimination was assessed via area under the receiver operating characteristic curve (AUC), and calibration was assessed via calibration plot.

RESULTS

A total of 105 events occurred in the 1188 cases. Age (>55 years) (OR: 1.83, P=0.0225), preoperative malnutrition (OR: 3.71, P<0.0001), diabetes mellitus(OR: 2.33, P=0.0036), CPB time (Cardiopulmonary Bypass Time) > 135 min (OR: 2.80, P<0.0001), moderate to severe ARDS (Acute Respiratory Distress Syndrome )(OR: 1.79, P=0.0148), use of ECMO or IABP or CRRT (ECMO: Extra Corporeal Membrane Oxygenation; IABP: Intra-Aortic Balloon Pump; CRRT: Continuous Renal Replacement Therapy )(OR: 2.60, P=0.0057) and MV( Mechanical Ventilation )> 20 hours (OR: 3.11, P<0.0001) were independent risk factors for POP. Based on those independent risk factors, we constructed a simple nomogram with an AUC of 0.82. Calibration plots showed good agreement between predicted probabilities and actual probabilities.

CONCLUSION

We constructed a facile nomogram for predicting pneumonia after cardiac surgery with good discrimination and calibration. The model has excellent clinical applicability and can be used to identify and adjust modifiable risk factors to reduce the incidence of POP as well as patient mortality.

Healthcare-associated infections in Iranian pediatric and adult intensive care units: A comprehensive review of risk factors, etiology, molecular epidemiology, antimicrobial sensitivity, and prevention strategies during the COVID-19 pandemic

The current review article provides a comprehensive analysis of nosocomial infections in pediatric and adult intensive care units (ICUs) in Iran. We examine the risk factors and etiology of nosocomial infections, with a particular focus on molecular epidemiology and antimicrobial sensitivity. In this article, we explore a range of prevention strategies, including hand hygiene, personal protective equipment, environmental cleaning, antibiotic stewardship, education, and training. Moreover, we discuss the impact of the COVID-19 pandemic on infection control measures in ICUs and provide valuable insights for healthcare professionals and policymakers seeking to address this critical public health issue. In conclusion, this review article can serve as a valuable resource for those interested in understanding and improving infection control in ICUs and beyond.

Use of nursing care bundles for the prevention of ventilator-associated pneumonia in low-middle income countries: A scoping review

BACKGROUND

Ventilator-associated pneumonia (VAP) is a significant concern in low-middle-income countries (LMICs), where the burden of hospital-acquired infections is high, and resources are low. Evidence-based guidelines exist for preventing VAP; however, these guidelines may not be adequately utilized in intensive care units of LMICs.

AIM

This scoping review examined the literature regarding the use of nursing care bundles for VAP prevention in LMICs, to understand the knowledge, practice and compliance of nurses to these guidelines, as well as the barriers preventing the implementation of these guidelines.

STUDY DESIGN

The review was conducted using Arksey and O'Malley's (2005) five-stage framework and the PRISMA-ScR guidelines guided reporting. Searches were performed across six databases: CINAHL, Medline, Embase, Global Health, Scopus and Cochrane, resulting in 401 studies.

RESULTS

After screening all studies against the eligibility criteria, 21 studies were included in the data extraction stage of the review. Across the studies, the knowledge and compliance of nurses regarding VAP prevention were reported as low to moderate. Several factors, ranging from insufficient knowledge to a lack of adequate guidelines for VAP management, served as contributing factors. Multiple barriers prevented nurses from adhering to VAP guidelines effectively, including a lack of audit/surveillance, absence of infection prevention and control (IPC) teams and inadequate training opportunities.

CONCLUSIONS

This review highlights the need for adequate quality improvement procedures and more efforts to conduct and translate research into practice in intensive care units in LMIC.

RELEVANCE TO CLINICAL PRACTICE

IPC practices are vital to protect vulnerable patients in intensive care units from developing infections and complications that worsen their prognosis. Critical care nurses should be trained and reinforced to practice effective bundle care to prevent VAP.

Hospital-acquired and ventilator-associated pneumonia caused by multidrug-resistant Gram-negative pathogens: Understanding epidemiology, resistance patterns, and implications with COVID-19

The ongoing spread of antimicrobial resistance has complicated the treatment of bacterial hospital-acquired pneumonia (HAP) and ventilator-associated pneumonia (VAP). Gram-negative pathogens, especially those with multidrug-resistant profiles, including Escherichia coli, Klebsiella pneumoniae, Enterobacter spp., Pseudomonas aeruginosa, and Acinetobacter spp., are important culprits in this type of infections. Understanding the determinants of resistance in pathogens causing pneumonia is ultimately stressing, especially in the shadows of the COVID-19 pandemic, when bacterial lung infections are considered a top priority that has become urgent to revise. Globally, the increasing prevalence of these pathogens in respiratory samples represents a significant infection challenge, with major limitations of treatment options and poor clinical outcomes. This review will focus on the epidemiology of HAP and VAP and will present the roles and the antimicrobial resistance patterns of implicated multidrug-resistant (MDR) Gram-negative pathogens like carbapenem-resistant Acinetobacter baumannii (CRAB), carbapenem-resistant Pseudomonas aeruginosa (CRPA), carbapenem-resistant Enterobacterales (CRE), as well as colistin-resistant Gram-negative pathogens and extended-spectrum β-lactamase (ESBL)-producing Enterobacterales. While emerging from the COVID-19 pandemic, perspectives and conclusions are drawn from findings of HAP and VAP caused by MDR Gram-negative bacteria in patients with COVID-19.

Identifying the barriers and facilitators to implementation of ventilator bundle in the nepalese intensive care unit: A descriptive qualitative study

BACKGROUND

A ventilator bundle is an effective preventive strategy against the development of ventilator-associated pneumonia (VAP). However, in clinical practice ventilator bundle implementation is poor. Understanding the barriers to ventilator bundle implementation in low- and middle-income countries can inform the development of effective implementation strategies to reduce the burden of VAP.

OBJECTIVES

The primary objective of this study was to explore the barriers and facilitators of ventilator bundle implementation perceived by healthcare professionals (HCPs) working in intensive care units (ICU) in Nepal. The secondary objective was to prioritise the barriers when developing implementation strategies.

METHODS

This study used a pragmatic approach comprising a series of methods to identify the implementation strategies: (i) Barriers and facilitators were explored using a qualitative study design. Twenty-one HCPs selected using the maximum variation sampling technique from a large tertiary hospital, completed semistructured interviews. All the interviews were recorded, transcribed word-by-word, and uploaded into NVivo for analysis using the thematic analysis approach. (ii) After analysis, nine participants were selecteded to determine the priority order of the barriers using a barrier identification and mitigation tool.

RESULTS

The data analysis revealed five main themes and 19 subthemes that affected ventilator bundle implementation. The main themes were provider-related factors, organisational and practice-related factors, performances of work, environmental conditions, and patient-related factors. The common barriers were job insecurity, poor knowledge, negative attitude, insufficient equipment, and severity of patient disease. Common facilitators were educational training, equipment functioning, adequate staff, strong leadership, and organisational support. Finally, eight main barriers were prioritised to target the change.

CONCLUSION

The barriers to implementing ventilator bundles in ICUs were identified. Focussing on addressing the prioritised barriers may aid in improving patient care and safety in ICUs. Results may guide HCPs in the development of implementation strategies to reduce the burden of VAP.

Comparative study of the etiology of nosocomial bacteremic pneumonia in ventilated and non-ventilated patients: a 10-year experience in an institution

IMPORTANCE

This study on bacteremic nosocomial pneumonia (bNP) demonstrates the importance of this condition both in patients undergoing and not undergoing mechanical ventilation. Staphylococcus aureus, Enterobacterales, and non-fermenting Gram-negative bacilli are all causative agents in ventilator-associated pneumonia (VAP) and hospital-acquired pneumonia (HAP), with a predominance of S. aureus in HAP and of Pseudomonas aeruginosa in VAP. Mortality in this condition is very high. Therefore, new therapeutic and preventive approaches should be sought.

Suction circuit flushing with chlorhexidine decreases ventilator-associated pneumonia: a quasi-experimental study

Background

Endotracheal suctioning of mechanically ventilated patients differs across the world. In many low and middle-income countries, endotracheal suctioning is often performed with a sterile suctioning catheter that is used for 12 h or during the length of one nursing shift. The effect of flushing multiple used endotracheal suction system with chlorhexidine after suctioning to reduce ventilator associated pneumonia (VAP) remains unclear.

Aim

The aim of the study is to assess the effectiveness of flushing multiple-used open endotracheal suction catheters and suctioning system with chlorhexidine gluconate 0.2% to reduce VAP in mechanically ventilated patients in a resource-limited Intensive Care Unit (ICU).

Methods

Due to the difficulty of blinding the intervention for nurses who perform endo-tracheal suction procedures, we adopted a quasi-experimental method with a randomized controlled trial design. A sample of 136 ICU patients were allocated to the intervention (n = 68) or control group (n = 68) between May and November 2020. The intervention was flushing the multiple-used suction catheter and suction system with 40ml chlorhexidine gluconate 0.2% and in the control group we used normal saline to flush the catheter and suction system. The primary outcome was incidence of VAP and the cost of the flushing solutions was the secondary outcome measure.

Results

Patients in the intervention group had a lower incidence of VAP compared to patients in the control group; 15 (22.1%) vs 29 (42.6%), p = 0.01. The incidence of late-onset VAP was 26.2% in the intervention group and 49% in the control group (p = 0.026) and the early-onset VAP was 13.2% in the intervention group and 25% in the control group (p = 0.081). Chlorhexidine gluconate 0.2% reduced the cost of suction system flushing (median: 78.4 vs 300 EGP, p < 0.001).

Conclusion

Using chlorhexidine gluconate 0.2% to flush multiple-used suctioning catheters after every endo-tracheal suction procedure might reduce the incidence of VAP in mechanically ventilated patients. Chlorhexidine gluconate 0.2% can be a cost-effective solution for flushing the suction circuit. Nurses working in resource-limited ICUs and using suctioning catheters multiple times might consider using chlorhexidine gluconate 0.2% instead of normal saline or distilled water when flushing the suction system.

Clinical trial registration

ClinicalTrials.gov, identifier NCT05206721.

Risk factors for neonatal VAP: A retrospective cohort study

Ventilator-associated pneumonia (VAP) is a serious complication in neonates requiring mechanical ventilation. This study aimed to determine the risk factors associated with the development of VAP in neonates admitted to the neonatal intensive care unit (NICU) of the Affiliated Hospital of Southwest Medical University. In a retrospective observational study, neonates admitted to the NICU from 1 January 2019, to 31 December 2021, requiring ventilation for more than 48 h were included. Neonates who died within 48 h of NICU admission, those without obtainable consent, or identified with a genetic syndrome were excluded. Various neonatal and clinical variables were evaluated. Univariate and multivariate analyses were performed to determine risk factors associated with VAP. Of the total neonates included, several risk factors were identified for VAP, such as being a premature infant and use of dexamethasone and sedatives. Moreover, reintubation was found to decrease the risk of VAP. Some factors like gestational age, birth weight, Apgar scores at 5 min, and other parameters were found not significantly associated with the development of VAP. The study identified several risk factors associated with the development of VAP in neonates. Recognizing these risk factors could help in the prevention and early management of VAP, thus improving the prognosis for these patients. Further studies are needed to validate these findings and explore the mechanistic links between these factors and VAP.

Inhaled Amikacin to Prevent Ventilator-Associated Pneumonia

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Teaching Bundle Care Approach to Intensive Care Nurses to Prevent Ventilator Associated Pneumonia with a Stratified Validated Module

BACKGROUND

Module-based teaching of ventilator-associated pneumonia (VAP) with a systematic, stratified approach is expected to have a promising role in teaching. We hypothesized it to improve the skill and knowledge of intensive care unit nurses.

OBJECTIVES

The aim of this study was to determine the efficacy of the teaching module with debriefing sessions on the VAP bundle care approach, and the secondary objective was to estimate the improvement in individual components of the VAP bundle.

METHODS

A total of 200 paramedical staff were exposed to a teaching module consisting of pretest didactic lectures, debriefing sessions, reflection by participants, and feedback. Posttest analysis was done to assess knowledge. Skill assessment was done with directly observed procedural skills (DOPS) assessment, and feedback was taken from participants. Follow-up was done at 6 months to assess decay in knowledge and skills.

RESULTS

Preworkshop and postworkshop DOPS scores were analyzed using the Mann-Whitney U test. Subgroup analysis was performed using the paired t test. Median pretest and posttest scores were 6 (interquartile range, 4-8) and 13 (interquartile range, 11-15), respectively (P < .001). Comparing DOPS scores before and after exposure to the teaching module, the number of subjects with scores that were below expectations was 24 and 4; meeting expectations was 94 and 24; borderline expectations were 36 and 104; and above expectations was 46 and 58, respectively, between the groups (P < .001). A decay in knowledge and skills was noted in the follow-up.

CONCLUSION

A validated teaching module with debriefing sessions is useful in training bundle care approaches to intensive care unit nurses.

Clinical Efficiency of Metagenomic Next-Generation Sequencing in Sputum for Pathogen Detection of Patients with Pneumonia According to Disease Severity and Host Immune Status

Purpose

Severe pneumonia causes the highest mortality rate in immunocompromised patients. This study aimed to investigate the pathogen diagnostic efficacy of metagenomic next-generation sequencing (mNGS) using sputum sample in patients with pneumonia according to patients' disease severity and immune conditions.

Patients and Methods

A total of 180 patients suffering from pneumonia were recruited, and sputum samples were collected in duplicate for pathogen detection by both conventional microbiological tests (CMT) and mNGS. Then, the performance of pathogen identification was examined between two methods, according to disease severity and patients' immune status.

Results

In comparison to CMT, mNGS had higher positivity rates in all patients with pneumonia (85.0% vs 62.2%, P=9.445e-07). The most commonly detected microorganism in sputum of pneumonia patients was Acinetobacter baumannii (42/180, 23.3%) in bacterum level, Candida albicans in fungus level (44/180, 24.4%), and Human herpesvirus 1 (39/180, 27.5%) in virus level. However, for mNGS results, Candida albicans in 34.9% of positive patients, and Human herpesvirus 1 in 7.7% of positive cases were confirmed as pathogens causing pneumonia. Acinetobacter baumannii detected by mNGS in 75% of positive patients was diagnosed as pathogen of pneumonia. The microorganism profile of sputum mNGS differed according to disease severity and immune status of patients. Pneumocystis jirovecii was more likely to infect immunocompromised patients (P=0.002). Pseudomonas aeruginosa (14.8% vs 0.0%, P=0.008) and Human herpesvirus 1 (26.1% vs 5.3%, P=0.004) had higher infection rate in patients with severe pneumonia compared with non-severe cases. mNGS had overwhelming advantages over CMT in detecting a lot of microorganisms including Streptococcus pneumoniae, Enterococcus faecium, Pneumocystis jirovecii, and majority of viruses.

Conclusion

mNGS is a complementary tool of CMT for detecting suspected pathogens for patients with lower respiratory infections. The interpretation of opportunistic pathogens identified by mNGS is challenging, and needs comprehensive consideration of sequencing data and clinical factors.

Exploring the complex relationship between the lung microbiome and ventilator-associated pneumonia

INTRODUCTION

Understanding the presence and function of a diverse lung microbiome in acute lung infections, particularly ventilator-associated pneumonia (VAP), is still limited, evidencing significant gaps in our knowledge.

AREAS COVERED

In this comprehensive narrative review, we aim to elucidate the contribution of the respiratory microbiome in the development of VAP by examining the current knowledge on the interactions among microorganisms. By exploring these intricate connections, we endeavor to enhance our understanding of the disease's pathophysiology and pave the way for novel ideas and interventions in studying the respiratory tract microbiome.

EXPERT OPINION

The conventional perception of lungs as sterile is deprecated since it is currently recognized the existence of a diverse microbial community within them. However, despite extensive research on the role of the respiratory microbiome in healthy lungs, respiratory chronic diseases and acute lung infections such as pneumonia are not fully understood. It is crucial to investigate further the relationship between the pathophysiology of VAP and the pulmonary microbiome, elucidating the mechanisms underlying the interactions between the microbiome, host immune response and mechanical ventilation for the development of VAP.

Distribution and antibacterial susceptibility pattern of isolated bacteria from endotracheal aspirates among ventilator-assisted pneumonia patients in Indonesia

An accurate and timely identification of causative microorganisms as well as determination of their antibiotic susceptibility patterns will help in the selection of proper antibiotics and prevention of their misuse in pneumonia patients. The aim of this study was to determine the distribution and antibiotic susceptibility pattern of bacteria isolated from endotracheal aspirates of ventilator-assisted pneumonia patients in Indonesia. A retrospective cross-sectional study was conducted at Dr. Zainoel Abidin Hospital, a provincial reference hospital in Banda Aceh, Indonesia, from January to December 2021. Ventilator-assisted pneumonia patients aged ≥17 years treated in the hospital were considered eligible. Antibiotic susceptibility was valuated using Kirby-Bauer disc-diffusion followed with VITEK 2 Compact. We included 57 patients of which 73.7% males and 26.3% aged 56-65 years (represent the majority group of the patients). Each patient reported at least one comorbidity and the average duration of receiving mechanical ventilation was 8.68 days, and more than half (59.7%) of the patients had a poor clinical outcome (died). A total 57 bacteria isolates (consisting nine species) were recovered; 68.5% Gram-negative and 31.5% Gram-positive bacteria. Among 57 patients, Acinetobacter baumannii was the most frequent isolated Gram-negative bacteria (19.3%), followed by Klebsiella pneumoniae (17.5%), Pseudomonas aeruginosa (15.8%), and Achromobacter denitrificans (12.3%). A. baumannii exhibited <70% sensitivity to aminoglycoside and carbapenem antibiotics and 100% resistance to third-generation cephalosporins. The most abundant Gram-positive bacteria was Staphylococcus aureus (17.5%), followed by S. haemolyticus (10.5%) and S. epidermidis (3.5%). All S. aureus were sensitive to linezolid, tigecycline, vancomycin, and macrolide antibiotics (azithromycin, clarithromycin, clindamycin, and erythromycin), whereas 50% were sensitive to some beta-lactams. However, 50% of S. aureus were methicillin resistant S. aureus (MRSA). Given the magnitude of multi-drug resistance, an empiric antimicrobial therapy in particular to specific settings and implementation of antibiotic stewardship programs are crucial.

Effect of clove mouthwash on the incidence of ventilator-associated pneumonia in intensive care unit patients: a comparative randomized triple-blind clinical trial

OBJECTIVES

Ventilator-associated pneumonia (VAP) is one of the most common nosocomial infections in intensive care units (ICUs), and the use of mouthwash is the most widely used method to prevent its incidence. The aim of this study was to investigate effect of clove mouthwash on the incidence of VAP in the ICU.

MATERIALS AND METHODS

This comparative, randomized, triple-blind, clinical trial was conducted on 168 eligible ICU patients at Kosar Hospital in Semnan, Iran, during 2021-2022, who were divided into intervention and control groups using random blocks. The intervention group received clove extract mouthwash at 6.66% concentration, and the control group received chlorhexidine 0.2% twice a day for 5 days (routine care). Data were collected using a demographic questionnaire, and disease severity was measured based on the Acute Physiology and Chronic Health Evaluation II (APACHE II) score, oral health status was examined using the Beck Oral Assessment Scale (BOAS), and VAP diagnosis was made based on the Modified Clinical Pulmonary Infection Score (MCPIS).

RESULTS

Before the intervention, there was no significant difference in disease severity (p = 0.412) and oral health status (p = 0.239) between the patients in the two groups. After the intervention, 20.2% of the patients in the intervention group and 41.7% of those in the control group acquired VAP. The risk of VAP was 2.06 times higher in the control group than in the intervention group (p = 0.005, 95% CI: 1.26-3.37, RR = 2.06), but the severity of VAP did not differ significantly between the patients in the two groups (p = 0.557).

CONCLUSION

The findings showed that clove mouthwash reduces the incidence of VAP significantly.

CLINICAL RELEVANCE

Clove mouthwash can be used as a simple and low-cost method to prevent VAP in ICU patients.

Inhibitory Effects of Trans-Cinnamaldehyde Against Pseudomonas aeruginosa Biofilm Formation

Pseudomonas aeruginosa biofilm formation has been considered to be an important determinant of its pathogenicity in most infections. The antibiofilm activity of trans-cinnamaldehyde (TC) against P. aeruginosa was investigated in this study. Results demonstrated that the minimum inhibitory concentration (MIC) of TC against P. aeruginosa was 0.8 mg/mL, and subinhibitory concentrations (SICs) was 0.2 mg/mL and below. Crystal violet staining showed that TC at 0.05-0.2 mg/mL reduced biofilm biomass in 48 h in a concentration-dependent mode. The formation area of TC-treated biofilms was significantly declined (p < 0.01) on the glass slides observed by light microscopy. Field-emission scanning electron microscopy further demonstrated that TC destroyed the biofilm morphology and structure. Confocal laser scanning microscopic observed the dispersion of biofilms and the reduction of exopolysaccharides after TC treatment stained with concanavalin A (Con-A)-fluorescein isothiocyanate conjugate and Hoechst 33258. Meanwhile, TC caused a significant decrease (p < 0.01) in the component of polysaccharides, proteins, and DNA in extracellular polymeric substance. The swimming and swarming motility and quorum sensing of P. aeruginosa was also found to be significantly inhibited (p < 0.01) by TC at SICs. Furthermore, SICs of TC repressed the several genes transcription associated with biofilm formation as determined by real-time quantitative polymerase chain reaction. Overall, our findings suggest that TC could be applied as natural and safe antibiofilm agent to inhibit the biofilm formation of P. aeruginosa.

Construction and Validation of a Predictive Model for the Risk of Ventilator-Associated Pneumonia in Elderly ICU Patients

Background

Ventilator-associated pneumonia (VAP) is among the most important hospital-acquired infections in an intensive-care unit setting. However, clinical practice lacks effective theoretical tools for preventing VAP in the elderly.

Aim

To describe the independent factors associated with VAP in elderly intensive-care unit (ICU) patients on mechanical ventilation (MV) and to construct a risk prediction model.

Methods

A total of 1851 elderly patients with MV in ICUs from January 2015 to September 2019 were selected from 12 tertiary hospitals. Study subjects were divided into a model group (n = 1219) and a validation group (n = 632). Two groups of patients were divided into a VAP group and a non-VAP group and compared. Univariate and logistic regression analyses were used to explore influencing factors for VAP in elderly ICU patients with MV, establish a risk prediction model, and draw a nomogram. We used the area under the receiver operating characteristic curve (AUROC) and the Hosmer-Lemeshow goodness-of-fit test to evaluate the predictive effect of the model. Findings regarding the length of ICU stay, surgery, C-reactive protein (CRP), and the number of reintubations were independent risk factors for VAP in elderly ICU patients with MV. Predictive-model verification results showed that the area under the curve (AUC) of VAP risk after MV in the modeling and verification groups was 0.859 and 0.813 (P < 0.001), respectively, while P values for the Hosmer-Lemeshow test in these two groups were 0.365 and 0.485, respectively.

Conclusion

The model could effectively predict the occurrence of VAP in elderly patients with MV in ICUs. This study is a retrospective study, so it has not been registered as a clinical study.

Biogenic nanosilver-fabricated endotracheal tube to prevent microbial colonization in a veterinary hospital

COVID-19 patients have often required prolonged endotracheal intubation, increasing the risk of developing ventilator-associated pneumonia (VAP). A preventive strategy is proposed based on an endotracheal tube (ETT) modified by the in situ deposition of eucalyptus-mediated synthesized silver nanoparticles (AgNPs). The surfaces of the modified ETT were embedded with AgNPs of approximately 28 nm and presented a nanoscale roughness. Energy dispersive X-ray spectroscopy confirmed the presence of silver on and inside the coated ETT, which exhibited excellent antimicrobial activity against Gram-positive and Gram-negative bacteria, and fungi, including multidrug-resistant clinical isolates. Inhibition of planktonic growth and microbial adhesion ranged from 99 to 99.999% without cytotoxic effects on mammalian cells. Kinetic studies showed that microbial adhesion to the coated surface was inhibited within 2 h. Cell viability in biofilms supplemented with human tracheal mucus was reduced by up to 95%. In a porcine VAP model, the AgNPs-coated ETT prevented adhesion of Pseudomonas aeruginosa and completely inhibited bacterial invasion of lung tissue. The potential antimicrobial efficacy and safety of the coated ETT were established in a randomized control trial involving 47 veterinary patients. The microbial burden was significantly lower on the surface of the AgNPs-coated ETT than on the uncoated ETT (p < 0.05). KEY POINTS: • Endotracheal tube surfaces were modified by coating with green-synthesized AgNPs • P. aeruginosa burden of endotracheal tube and lung was reduced in a porcine model • Effective antimicrobial activity and safety was demonstrated in a clinical trial.

Ventilator-Associated Pneumonia Caused by Multidrug-Resistant Gram-Negative Bacteria in Vietnam: Antibiotic Resistance, Treatment Outcomes, and Colistin-Associated Adverse Effects

Background: Ventilator-associated pneumonia (VAP) caused by multidrug-resistant (MDR) gram-negative bacteria (GNB) presents a serious clinical scenario, and there is disagreement regarding the role of colistin in treatment. This study aimed to characterize the antibiotic resistance of MDR GNB and evaluate the treatment outcomes and side effects of colistin in VAP patients caused by MDR GNB, particularly in Vietnam. Methods: A prospective cohort research was undertaken. We enrolled 136 intubated patients diagnosed with VAP according to the Centers for Disease Control and Prevention (CDC) 2019. Sixty-six individuals with an isolated gram-negative bacterium (Acinetobacter baumannii, Klebsiella pneumoniae, or Pseudomonas aeruginosa) satisfied the European Centre for Disease Prevention and Control (ECDC)’s criteria for multi-antibiotic resistance. Results: GNB resistance was categorized as 10.6% MDR, 63.6% XDR, and 25.8% PDR. GNB were resistant to β-lactams 80–100%, aminoglycosides 50–86.7%, fluoroquinolones 100% and colistin 2.8–20%. The 28-day mortality rate was 54.5%, and acute kidney injury occurred at 12.1%. There was no statistically significant difference in mortality rate between groups receiving regimens with or without colistin (58.3% and 73.3%, respectively; OR = 1.964; 95%CI 0.483–7.989). Neither was there a statistically significant difference in acute renal damage rate between groups receiving regimens with or without colistin (14.3% and 9.7%, respectively; OR = 1.556; 95%CI 0.34–7.121). Conclusions: GNB had a high rate of antibiotic resistance to most antibiotics. The addition of colistin to the medication did not show significant differences in renal toxicity or mortality, while colistin resistance was relatively low; larger studies need to be conducted.

Physical oral care prevents ventilator-associated pneumonia in Vietnam: A prospective interventional study

BACKGROUND

Ventilator-associated pneumonia (VAP) has emerged as a critical issue in the intensive care unit (ICU) because of its high burden on patients and medical staff. Here, we examined the potential for reducing VAP incidence through physical oral care interventions without any medication.

METHODS

This prospective interventional study compared VAP incidence during an 8-month baseline period (usual oral care) and a 9-month intervention period (physical oral care with sponge brush) among patients who received mechanical ventilation for >48 h in a tertiary care hospital in Vietnam from 2017 to 2019. Physical oral care was provided by general ICU nurses who had been trained by dentists and infection control nurses. VAP was diagnosed using the Clinical Pulmonary Infection Score.

RESULTS

In total, 423 patients were enrolled in the baseline group and 454 patients were enrolled in the intervention group; 303 and 300 patients, respectively, were included in the analysis. Two hundred thirty-eight VAP episodes were identified: 135 (44.6%) during the baseline period and 103 (34.3%) during the intervention period. Univariate analysis revealed significant reduction of VAP occurrence in the intervention period (odds ratio = 0.65; 95% confidence interval = 0.47-0.90; P = 0.010). The incidences of VAP per 1000 ventilator-days were 63.4 (135/2128) during the baseline period and 48.4 (103/2128) during the intervention period (P = 0.038).

CONCLUSIONS

Physical oral care without any medication (e.g., chlorhexidine) reduced VAP incidence in the ICU. This method could be used to reduce VAP incidence, particularly in countries with limited medical resources.

Effects of Gastric Acid Secretion Inhibitors for Ventilator-Associated Pneumonia

Objective: This study analyzed the association of gastric acid secretion inhibitors (GASIs) [including proton pump inhibitors (PPIs) and histamine 2 receptor antagonists (H2RAs)] with the occurrence of ventilator-associated pneumonia (VAP) and in-hospital mortality in patients who received invasive mechanical ventilation (IMV).

Method: Patients who received IMV and used GASI were included based on records in the MIMIC-IV database. The relationships of GASIs with VAP and the in-hospital mortality were determined using univariate and multivariate logistic regression analyses. Also, the effects of GASIs in some subgroups of the population were further analyzed.

Results: A total of 18,669 patients were enrolled, including 9191 patients on H2RAs only, 6921 patients on PPIs only, and 2557 were on a combination of the two drugs. Applying logistic regression to the univariate and multivariate models revealed that compared with H2RAs, PPIs had no significant effect on the incidence of VAP, and the combination of H2RAs and PPIs was a risk factor for VAP. Compared with H2RAs, univariate logistic regression revealed that, PPIs and combine the two drugs were both risk factors for in-hospital mortality, but multivariate logistic regression showed that they were not significantly associated with in-hospital mortality. In subgroup analysis, there were interaction in different subgroups of age, PCO2, myocardial infarct, congestive heart failure (P for interaction<0.05).

Conclusion: Compared with H2RAs, PPIs did not have a significant association with either VAP or in-hospital mortality; the combination of H2RAs and PPIs was risk factor for VAP, but did not have a significantly associated with in-hospital mortality.

Probiotic in the prevention of ventilator-associated pneumonia in critically ill patients: evidence from meta-analysis and trial sequential analysis of randomized clinical trials

BACKGROUND

Probiotic might have a role in the prevention of ventilator-associated pneumonia (VAP) among mechanically ventilated patients, but the efficacy and safety remained inconsistent. The aim of this systematic review and meta-analysis was to evaluate the efficacy and safety of probiotic (prebiotic, synbiotic) versus placebo in preventing VAP in critically ill patients undergoing mechanical ventilation.

METHODS

PubMed, Embase and the Cochrane library databases were searched to 10 October 2021 without language restriction for randomized or semi-randomized controlled trials evaluating probiotic (prebiotic, synbiotic) vs. placebo in prevention of VAP in critically ill mechanically ventilated patients. The pooled relative risk (RR) along with 95% confidence intervals (CI) were combined using a random-effects model. Furthermore, the trial sequential analysis (TSA) and subgroup analyses were performed. Statistical significance was regarded as P < 0.05.

RESULTS

Twenty-three trials involving 5543 patients were eligible for this meta-analysis. The combined RR of decreasing the risk of VAP by probiotic was 0.67 (0.56, 0.81) for all eligible studies, 0.69 (n = 5136; 95% CI = 0.57 to 0.84; P < 0.01) for adults studies and 0.55 (n = 407; 95%CI = 0.31 to 0.99; P = 0.046) for neonates/children studies. Additionally, the above-mentioned positive finding in 20 adults studies was verified by the results of TSA, subgroup analyses and cumulative meta-analysis. Ample evidences demonstrated a 31% decrease in RR of incidence of VAP was noted when prophylactic probiotic therapy was administrated among adult patients. Finally, there were no effects on the ICU/hospital/28-/90-day mortality, bacteremia, CRBSI, diarrhea, ICU-acquired infections, infectious complications, pneumonia, UTI and wound infection between two groups (P > 0.05 for all).

CONCLUSIONS

Based on the results of our study, the current evidences suggested that prophylactic administration of probiotic might be utilized as a preventive method for VAP in neonates/children and adults patients who required mechanical ventilation. However, further large, high-quality RCTs are warranted to assess the efficacy and safety of probiotic treatment in critically ill patients, especially for the neonates/children studies and the long-term consequences of this therapy.

The necessity of a loading dose when prescribing intravenous colistin in critically ill patients with CRGNB-associated pneumonia: a multi-center observational study

Background

The importance or necessity of a loading dose when prescribing intravenous colistin has not been well established in clinical practice, and approximate one-third to half of patients with carbapenem-resistant gram-negative bacteria (CRGNB) infection did not receive the administration of a loading dose. The aim of this study is to investigate the efficacy and risk of acute kidney injury when prescribing intravenous colistin for critically ill patients with nosocomial pneumonia caused by CRGNB.

Methods

This was a multicenter, retrospective study that recruited ICU-admitted patients who had CRGNB-associated nosocomial pneumonia and were treated with intravenous colistin. Then, we classified the patients into colistin loading dose (N = 85) and nonloading dose groups (N = 127). After propensity-score matching for important covariates, we compared the mortality rate, clinical outcome and microbiological eradication rates between the groups (N = 67).

Results

The loading group had higher percentages of patients with favorable clinical outcomes (55.2% and 35.8%, p = 0.037) and microbiological eradication rates (50% and 27.3%, p = 0.042) at day 14 than the nonloading group. The mortality rates at days 7, 14 and 28 and overall in-hospital mortality were not different between the two groups, but the Kaplan–Meier analysis showed that the loading group had a longer survival time than the nonloading group. Furthermore, the loading group had a shorter length of hospital stay than the nonloading group (52 and 60, p = 0.037). Regarding nephrotoxicity, there was no significant difference in the risk of developing acute kidney injury between the groups.

Conclusions

The administration of a loading dose is recommended when prescribing intravenous colistin for critically ill patients with nosocomial pneumonia caused by CRGNB.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13054-022-03947-9.

Geoeconomic variations in epidemiology, ventilation management, and outcomes in invasively ventilated intensive care unit patients without acute respiratory distress syndrome: a pooled analysis of four observational studies

Background

Geoeconomic variations in epidemiology, the practice of ventilation, and outcome in invasively ventilated intensive care unit (ICU) patients without acute respiratory distress syndrome (ARDS) remain unexplored. In this analysis we aim to address these gaps using individual patient data of four large observational studies.

Methods

In this pooled analysis we harmonised individual patient data from the ERICC, LUNG SAFE, PRoVENT, and PRoVENT-iMiC prospective observational studies, which were conducted from June, 2011, to December, 2018, in 534 ICUs in 54 countries. We used the 2016 World Bank classification to define two geoeconomic regions: middle-income countries (MICs) and high-income countries (HICs). ARDS was defined according to the Berlin criteria. Descriptive statistics were used to compare patients in MICs versus HICs. The primary outcome was the use of low tidal volume ventilation (LTVV) for the first 3 days of mechanical ventilation. Secondary outcomes were key ventilation parameters (tidal volume size, positive end-expiratory pressure, fraction of inspired oxygen, peak pressure, plateau pressure, driving pressure, and respiratory rate), patient characteristics, the risk for and actual development of acute respiratory distress syndrome after the first day of ventilation, duration of ventilation, ICU length of stay, and ICU mortality.

Findings

Of the 7608 patients included in the original studies, this analysis included 3852 patients without ARDS, of whom 2345 were from MICs and 1507 were from HICs. Patients in MICs were younger, shorter and with a slightly lower body-mass index, more often had diabetes and active cancer, but less often chronic obstructive pulmonary disease and heart failure than patients from HICs. Sequential organ failure assessment scores were similar in MICs and HICs. Use of LTVV in MICs and HICs was comparable (42·4% vs 44·2%; absolute difference –1·69 [–9·58 to 6·11] p=0·67; data available in 3174 [82%] of 3852 patients). The median applied positive end expiratory pressure was lower in MICs than in HICs (5 [IQR 5–8] vs 6 [5–8] cm H₂O; p=0·0011). ICU mortality was higher in MICs than in HICs (30·5% vs 19·9%; p=0·0004; adjusted effect 16·41% [95% CI 9·52–23·52]; p<0·0001) and was inversely associated with gross domestic product (adjusted odds ratio for a US$10 000 increase per capita 0·80 [95% CI 0·75–0·86]; p<0·0001).

Interpretation

Despite similar disease severity and ventilation management, ICU mortality in patients without ARDS is higher in MICs than in HICs, with a strong association with country-level economic status.

Funding

No funding.

C. R, Thwaites L, Basnyat B, Baker S, Karkey A. Epidemiology, etiology, and diagnosis of health care acquired pneumonia including ventilator-associated pneumonia in Nepal

Epidemiologic data regarding health care acquired pneumonia (HAP) and ventilator-associated pneumonia (VAP) from Nepal are negligible. We conducted a prospective observational cohort study in the intensive care unit (ICU) of a major tertiary hospital in Nepal between April 2016 and March 2018, to calculate the incidence of VAP, and to describe clinical variables, microbiological etiology, and outcomes. Four hundred and thirty-eight patients were enrolled in the study. Demographic data, medical history, antimicrobial administration record, chest X-ray, biochemical, microbiological and haematological results, acute physiology and chronic health evaluation II score and the sequential organ failure assessment scores were recorded. Categorical variables were expressed as count and percentage and analyzed using the Fisher's exact test. Continuous variables were expressed as median and interquartile range and analyzed using Kruskal-Wallis rank sum test and the pairwise Wilcoxon rank-sum test. 46.8% (205/438) of the patients required intubation. Pneumonia was common in both intubated (94.14%; 193/205) and non-intubated (52.36%; 122/233) patients. Pneumonia developed among intubated patients in the ICU had longer days of stay in the ICU (median of 10, IQR 5-15, P< 0.001) when compared to non-intubated patients with pneumonia (median of 4, IQR 3-6, P< 0.001). The incidence rate of VAP was 20% (41/205) and incidence density was 16.45 cases per 1,000ventilator days. Mortality was significantly higher in patients with pneumonia requiring intubation (44.6%, 86/193) than patients with pneumonia not requiring intubation (10.7%, 13/122, p<0.001, Fisher's exact test). Gram negative bacteria such as Klebsiella and Acinetobacter species were the dominant organisms from both VAP and non-VAP categories. Multi-drug resistance was highly prevalent in bacterial isolates associated with VAP (90%; 99/110) and non-VAP categories (81.5%; 106/130). HAP including VAP remains to be the most prevalent hospital-acquired infections (HAIs) at Patan hospital. A local study of etiological agents and outcomes of HAP and VAP are required for setting more appropriate guidelines for management of such diseases.

Development and Validation of Nomogram Models for Postoperative Pneumonia in Adult Patients Undergoing Elective Cardiac Surgery

Background: Postoperative pneumonia (POP) is a frequent complication following cardiac surgery, related to increased morbidity, mortality and healthcare costs. The objectives of this study were to investigate the risk factors associated with POP in adults undergoing elective cardiac surgery and to develop and validate nomogram models.

Methods: We conducted a multicenter retrospective study in four cardiac centers in China. Adults operated with elective open-heart surgery from 2016 to 2020 were included. Patients were randomly allocated to training and validation sets by 7:3 ratio. Demographics, comorbidities, laboratory data, surgical factors, and postoperative outcomes were collected and analyzed. Risk factors for POP were identified by univariate and multivariate analysis. Nomograms were constructed based on the multivariate logistic regression models and were evaluated with calibration, discrimination and decision curve analysis.

Results: A total of 13,380 patients meeting the criteria were included and POP developed in 882 patients (6.6%). The mortality was 2.0%, but it increased significantly in patients with POP (25.1 vs. 0.4%, P < 0.001). Using preoperative and intraoperative variables, we constructed a full nomogram model based on ten independent risk factors and a preoperative nomogram model based on eight preoperative factors. Both nomograms demonstrated good calibration, discrimination, and were well validated. The decision curves indicated significant clinical usefulness. Finally, four risk intervals were defined for better clinical application.

Conclusions: We developed and validated two nomogram models for POP following elective cardiac surgery using preoperative and intraoperative factors, which may be helpful for individualized risk evaluation and prevention decisions.

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

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

Evidence Map and Systematic Review of Disinfection Efficacy on Environmental Surfaces in Healthcare Facilities

Healthcare-associated infections (HAIs) contribute to patient morbidity and mortality with an estimated 1.7 million infections and 99,000 deaths costing USD $28-34 billion annually in the United States alone. There is little understanding as to if current environmental surface disinfection practices reduce pathogen load, and subsequently HAIs, in critical care settings. This evidence map includes a systematic review on the efficacy of disinfecting environmental surfaces in healthcare facilities. We screened 17,064 abstracts, 635 full texts, and included 181 articles for data extraction and study quality assessment. We reviewed ten disinfectant types and compared disinfectants with respect to study design, outcome organism, and fourteen indictors of study quality. We found important areas for improvement and gaps in the research related to study design, implementation, and analysis. Implementation of disinfection, a determinant of disinfection outcomes, was not measured in most studies and few studies assessed fungi or viruses. Assessing and comparing disinfection efficacy was impeded by study heterogeneity; however, we catalogued the outcomes and results for each disinfection type. We concluded that guidelines for disinfectant use are primarily based on laboratory data rather than a systematic review of in situ disinfection efficacy. It is critically important for practitioners and researchers to consider system-level efficacy and not just the efficacy of the disinfectant.

Prevention of VAP: Endless evolving evidences-systematic literature review

INTRODUCTION

Prevention of ventilator associated pneumonia (VAP) is the focus in critical care units. Immunocompromised patients, older adults, and postoperative patients are at greater risk for VAP. With the dynamic changes in the empirical world, updated evidence must be used to guide the standard of practice. This literature review assimilates the recent evidence for VAP prevention.

METHOD

The Preferred Reporting Items for Systematic Reviews and Meta-analysis framework guided the selection of the included research articles. Medline, EBSCO host, CINAHL, UpToDate and Google Scholar databases explored, for relevant publications between 2010 and 2020. The quality of evidence for the 14 studies selected were rated using the hierarchy of quantitative research designs.

RESULTS

Evidence-based VAP preventive strategies are prevention of aspiration, minimizing ventilator days, reducing the pathogen load, safe endotracheal suction practices, and pharmaceutical preventive measures. The mandates for VAP preventive measures among coronavirus disease 2019 (COVID-19) patients is included.

CONCLUSION

Though some of these themes identify with the past, the nuances in their implementation are highlights of this review. The review reiterates the need to revisit ambiguous practices implemented for VAP prevention. Adherence to evidence-based practices, by education, training, and reduction of workload is the key to VAP prevention.

Clinical risk score for postoperative pneumonia following heart valve surgery

Background:

Postoperative pneumonia (POP) is one of the most common infections following heart valve surgery (HVS) and is associated with a significant increase in morbidity, mortality, and health care costs. This study aimed to identify the major risk factors associated with the occurrence of POP following HVS and to derive and validate a clinical risk score.

Methods:

Adults undergoing open HVS between January 2016 and December 2019 at a single institution were enrolled in this study. Patients were randomly assigned to the derivation and validation sets at 1:1 ratio. A prediction model was developed with multivariable logistic regression analysis in the derivation set. Points were assigned to independent risk factors based on their regression coefficients.

Results:

POP occurred in 316 of the 3853 patients (8.2%). Multivariable analysis identified ten significant predictors for POP in the derivation set, including older age, smoking history, chronic obstructive pulmonary disease, diabetes mellitus, renal insufficiency, poor cardiac function, heart surgery history, longer cardiopulmonary bypass, blood transfusion, and concomitant coronary and/or aortic surgery. A 22-point risk score based on the multivariable model was then generated, demonstrating good discrimination (C-statistic: 0.81), and calibration (Hosmer-Lemeshow χ² = 8.234, P = 0.312). The prediction rule also showed adequate discriminative power (C-statistic: 0.83) and calibration (Hosmer-Lemeshow χ² = 5.606, P = 0.691) in the validation set. Three risk intervals were defined as low-, medium-, and high-risk groups.

Conclusion:

We derived and validated a 22-point risk score for POP following HVS, which may be useful in preventive interventions and risk management.

Trial Registration:

Chictr.org, ChiCTR1900028127; http://www.chictr.org.cn/showproj.aspx?proj=46932

Efficacies of Colistin-Carbapenem versus Colistin-Tigecycline in Critically Ill Patients with CR-GNB-Associated Pneumonia: A Multicenter Observational Study

Background: Evaluating the options for antibiotic treatment for carbapenem-resistant Gram-negative bacteria (CR-GNB)-associated pneumonia remains crucial. We compared the therapeutic efficacy and nephrotoxicity of two combination therapies, namely, colistin + carbapenem (CC) versus colistin + tigecycline (CT), for treating CR-GNB-related nosocomial pneumonia in critically ill patients. Methods: In this multicenter, retrospective, and cohort study, we recruited patients admitted to intensive care units and diagnosed with CR-GNB-associated nosocomial pneumonia. We divided the enrolled patients into CC (n = 62) and CT (n = 59) groups. After propensity score matching (n = 39), we compared the therapeutic efficacy by mortality, favorable outcome, and microbiological eradication and compared nephrotoxicity by acute kidney injury between groups. Results: There was no significant difference between the CC and CT groups regarding demographic characteristics and disease severities as assessed using the Acute Physiology and Chronic Health Evaluation (APACHE) II score, Sequential Organ Failure Assessment (SOFA) score, and other organ dysfunction variables. Therapeutic efficacy was non-significantly different between groups in all-cause mortality, favorable outcomes, and microbiological eradication at days 7, 14, and 28; as was the Kaplan-Meier analysis of 28-day survival. For nephrotoxicity, both groups had similar risks of developing acute kidney injury, evaluated using the Kidney Disease Improving Global Outcomes criteria (p = 1.000). Conclusions: Combination therapy with CC or CT had similar therapeutic efficacy and risk of developing acute kidney injury for treating CR-GNB-associated nosocomial pneumonia in critically ill patients.

Effectiveness of continuous endotracheal cuff pressure control for the prevention of ventilator associated respiratory infections: an open-label randomised, controlled trial

Background

An endotracheal tube cuff pressure between 20 and 30 cmH₂O is recommended to prevent ventilator-associated respiratory infection (VARI). We aimed to evaluate whether continuous cuff pressure control (CPC) was associated with reduced VARI incidence compared with intermittent CPC.

Methods

We conducted a multicenter open-label randomized controlled trial in intensive care unit (ICU) patients within 24 hours of intubation in Vietnam. Patients were randomly assigned 1:1 to receive either continuous CPC using an automated electronic device or intermittent CPC using a manually hand-held manometer. The primary endpoint was the occurrence of VARI, evaluated by an independent reviewer blinded to the CPC allocation.

Results

We randomized 600 patients; 597 received the intervention or control and were included in the intention to treat analysis. Compared with intermittent CPC, continuous CPC did not reduce the proportion of patients with at least one episode of VARI (74/296 [25%] vs 69/301 [23%]; odds ratio [OR] 1.13; 95% confidence interval [CI] .77–1.67]. There were no significant differences between continuous and intermittent CPC concerning the proportion of microbiologically confirmed VARI (OR 1.40; 95% CI .94–2.10), the proportion of intubated days without antimicrobials (relative proportion [RP] 0.99; 95% CI .87–1.12), rate of ICU discharge (cause-specific hazard ratio [HR] 0.95; 95% CI .78–1.16), cost of ICU stay (difference in transformed mean [DTM] 0.02; 95% CI −.05 to .08], cost of ICU antimicrobials (DTM 0.02; 95% CI −.25 to .28), cost of hospital stay (DTM 0.02; 95% CI −.04 to .08), and ICU mortality risk (OR 0.96; 95% CI .67–1.38).

Conclusions

Maintaining CPC through an automated electronic device did not reduce VARI incidence.

Clinical Trial Registration

NCT02966392.

Multi-Drug Resistance Bacterial Infections in Critically Ill Patients Admitted with COVID-19

Introduction. It is known that bacterial infections represent a common complication during viral respiratory tract infections such as influenza, with a concomitant increase in morbidity and mortality. Nevertheless, the prevalence of bacterial co-infections and secondary infections in critically ill patients affected by coronavirus disease 2019 (COVID-19) is not well understood yet. We performed a review of the literature currently available to examine the incidence of bacterial secondary infections acquired during hospital stay and the risk factors associated with multidrug resistance. Most of the studies, mainly retrospective and single-centered, highlighted that the incidence of co-infections is low, affecting about 3.5% of hospitalized patients, while the majority are hospital acquired infections, developed later, generally 10–15 days after ICU admission. The prolonged ICU hospitalization and the extensive use of broad-spectrum antimicrobial drugs during the COVID-19 outbreak might have contributed to the selection of pathogens with different profiles of resistance. Consequently, the reported incidence of MDR bacterial infections in critically ill COVID-19 patients is high, ranging between 32% to 50%. MDR infections are linked to a higher length of stay in ICU but not to a higher risk of death. The only risk factor independently associated with MDR secondary infections reported was invasive mechanical ventilation (OR 1.062; 95% CI 1.012–1.114), but also steroid therapy and prolonged length of ICU stay may play a pivotal role. The empiric antimicrobial therapy for a ventilated patient with suspected or proven bacterial co-infection at ICU admission should be prescribed judiciously and managed according to a stewardship program in order to interrupt or adjust it on the basis of culture results.

Superinfection associated with prolonged antibiotic use in non-ventilator associated hospital-acquired pneumonia

Background Non-ventilator associated hospital-acquired pneumonia accounts for significant antibiotic use and is associated with a high rate of resistance emergence. However, the optimal duration of antibiotic treatment is uncertain, especially in cases of non-fermenting gram-negative bacilli. Objective To compare a short course (5-7 days) to a prolonged course (10-14 days) of antibiotics for non-ventilator associated hospital-acquired pneumonia. Methods Data collected retrospectively on patients completed treatment in a Malaysian tertiary hospital from January 2017 till December 2018. Regression analysis determined variables independently associated with clinical outcome. Main outcome measures Clinical resolution, superinfection, 30-day and 90-day all-cause mortality between short and prolonged courses. Results Of the 167 patients included, 112 patients were treated with a short course antibiotic, whereas 55 patients received a prolonged course of therapy. Neither short nor prolonged course group has a significantly higher rate of clinical resolution. Short course group had significantly higher mean ± SD antibiotic-free days (21.9 ± 3.5 versus 15.1 ± 6.2 days, p < 0.001). Higher rate of superinfection was observed in prolonged course group compared to short course group (6.3% versus 18.2%, p = 0.027). For non-ventilator associated hospital-acquired pneumonia caused by non-fermenting gram-negative bacilli, the superinfection rate was higher in prolonged course group (35.7% versus 15.4%, p = 0.385) while 30-day mortality rate was higher in the short course group (38.5% versus 14.3%, p = 0.209). Non-fermenting gram-negative bacilli cause higher rate of superinfection (p = 0.010). Conclusion We found no clinical benefit as defined by clinical resolution and reduction in all-cause mortality in prolonging antimicrobial therapy. Superinfections emerge more frequently in prolonged course of antibiotic therapy and more likely to develop in non-fermenting gram-negative bacilli.

Biofilm Formation by Pathogens Causing Ventilator-Associated Pneumonia at Intensive Care Units in a Tertiary Care Hospital: An Armor for Refuge

Background

Emerging threat of drug resistance among pathogens causing ventilator-associated pneumonia (VAP) has resulted in higher hospital costs, longer hospital stays, and increased hospital mortality. Biofilms in the endotracheal tube of ventilated patients act as protective shield from host immunity. They induce chronic and recurrent infections that defy common antibiotics. This study intended to determine the biofilm produced by pathogens causing VAP and their relation with drug resistance.

Methods

Bronchoalveolar lavage and deep tracheal aspirates (n = 70) were obtained from the patients mechanically ventilated for more than 48 hours in the intensive care units of Tribhuvan University Teaching Hospital, Kathmandu, and processed according to the protocol of the American Society for Microbiology (ASM). Antibiotic susceptibility testing was done following Clinical and Laboratory Standards Institute (CLSI) 2017 guidelines. Biofilm formation was determined using the microtiter plate method described by Christensen and modified by Stepanovoic et al.

Results

Significant microbial growth was seen in 78.6% of the total samples with 52.7% monomicrobial, 45.5% polymicrobial, and 1.8% fungal infection. Among the 71 isolates obtained, bulk was gram-negative (n = 64, 90.1%). Pseudomonas aeruginosa (31.0%) was the predominant isolate followed by Acinetobacter calcoaceticus baumannii complex (16.9%), Klebsiella pneumoniae (16.9%), Citrobacter freundii (15.5%), Staphylococcus aureus (7.0%), Escherichia coli (5.6%), Citrobacter koseri (2.8%), Enterococcus faecalis (1.4%), Burkholderia cepacia complex (1.4%), and Candida albicans (1.4%). Of the total isolates, 56.3% were biofilm producers. Multidrug-resistant (MDR) organisms, extended-spectrum β-lactamase (ESBL), and metallo-β-lactamase (MBL) producers were preeminent among the biofilm producers. The highest producer of biofilm was P. aeruginosa (19.7%). Among gram-negative biofilm producers, 42.2% were MDR, 21.9% were ESBL producers, and 7.8% were MBL producers.

Conclusion

Gram-negative nonfermenter bacteria account for the bulk of nosocomial pneumonia. MDR, ESBL, and MBL production was preponderant among the biofilm producers. The rampant spread of drug resistance among biofilm producers is summoning novel interventions to combat multidrug resistance.

Pneumonia

Pneumonia is a common acute respiratory infection that affects the alveoli and distal airways; it is a major health problem and associated with high morbidity and short-term and long-term mortality in all age groups worldwide. Pneumonia is broadly divided into community-acquired pneumonia or hospital-acquired pneumonia. A large variety of microorganisms can cause pneumonia, including bacteria, respiratory viruses and fungi, and there are great geographical variations in their prevalence. Pneumonia occurs more commonly in susceptible individuals, including children of <5 years of age and older adults with prior chronic conditions. Development of the disease largely depends on the host immune response, with pathogen characteristics having a less prominent role. Individuals with pneumonia often present with respiratory and systemic symptoms, and diagnosis is based on both clinical presentation and radiological findings. It is crucial to identify the causative pathogens, as delayed and inadequate antimicrobial therapy can lead to poor outcomes. New antibiotic and non-antibiotic therapies, in addition to rapid and accurate diagnostic tests that can detect pathogens and antibiotic resistance will improve the management of pneumonia.

Critical care nurses' compliance and barriers toward ventilator-associated pneumonia prevention guidelines: cross-sectional survey

OBJECTIVES

This study aims to determine the compliance of critical care nurses with the ventilator-associated pneumonia prevention guidelines and the factors that affect their compliance. We also explored the barriers faced by the nurses in the implementation of these guidelines.

METHODS

A cross-sectional descriptive survey was conducted using a self-administered questionnaire containing 17 recommended strategies to prevent ventilator-associated pneumonia and 15 possible barriers. All critical care nurses of varying qualifications, levels of experience, and nationalities working in adult ICUs were invited. Between January and March 2018, the questionnaire was distributed to 283 nurses at eight ICUs in five public hospitals in Almadinah Almunawwarah, KSA.

RESULTS

A total of 229 invitees responded to the questionnaire. The mean compliance score was 85.9%. More than half (54%) of the sample had a high or acceptable compliance level. The lowest compliance rate was reported for the suctioning of subglottic secretions. The main reported barriers were the shortage of nursing staff, forgetfulness, and hospital cost control policies. Working in general ICUs with the capacity of 10-15 beds or prior education related to ventilator-associated pneumonia prevention influenced the nurses' compliance.

CONCLUSION

In our study, the overall compliance of the critical care nurses with the ventilator-associated pneumonia prevention guidelines is acceptable. Shortage of nursing staff, forgetfulness, and cost control policies were the main reported barriers to compliance.

Risk factors for postoperative pneumonia after cardiac surgery: a prediction model

Background

Postoperative pneumonia is the main infectious complication following cardiac surgery and is associated with significant increases in morbidity, mortality and health care costs. The aim of this study was to identify potential risk factors related to the occurrence of postoperative pneumonia in adult patients undergoing cardiac surgery and to develop a predictive system.

Methods

Adult patients who underwent open heart surgery in our institution between 2016 and 2019 were enrolled in this study. Preoperative and intraoperative variables were collected and analyzed. A multivariate prediction model for evaluating the risk of postoperative pneumonia was established using logistic regression analysis via forward stepwise selection, and points were assigned to significant risk factors based on their regression coefficient values.

Results

Postoperative pneumonia occurred in 530 of the 5,323 patients (9.96%). Prolonged stays in the postoperative intensive care unit (ICU) and hospital, as well as higher mortality (25.66% versus 0.65%), were observed in patients with postoperative pneumonia. Multivariate analysis identified 13 independent risk factors including patient demographics, comorbidities, cardiac function, cardiopulmonary bypass (CPB) duration, and blood transfusion. The prediction model showed good discrimination (C-statistic: 0.80) and was well calibrated (Hosmer-Lemeshow χ²=7.907, P value =0.443). A 32-point risk score was generated, and then three risk intervals were defined.

Conclusions

We derived and validated a prediction model for postoperative pneumonia after cardiac surgery incorporating 13 easily discernible risk factors. The scoring system may be helpful for individualized risk estimations and clinical decision-making.

Optimization of 2-Acylaminocycloalkylthiophene Derivatives for Activity against Staphylococcus aureus RnpA

Staphylococcus aureus is well-recognized to cause debilitating bacterial infections that are difficult to treat due to the emergence of antibiotic resistance. As such, there is a need to develop new antimicrobials for the therapeutic intervention of S. aureus disease. To that end, S. aureus RnpA is an essential enzyme that is hypothesized to participate in two required cellular processes, precursor tRNA (ptRNA) maturation and mRNA degradation. Corresponding high throughput screening campaigns have identified the phenylcarbamoyl cyclic thiopenes as a chemical class of RnpA inhibitors that display promising antibacterial effects by reducing RnpA ptRNA and mRNA degradation activities and low human cell toxicity. Herein, we perform a structure activity relationship study of the chemical scaffold. Results revealed that the cycloalkane ring size and trifluoroacetamide moiety are required for antibacterial activity, whereas modifications of the para and/or meta positions of the pharmacophore’s phenyl group allowed tuning of the scaffold’s antimicrobial performance and RnpA inhibitory activity. The top performing compounds with respect to antimicrobial activity also did not exhibit cytotoxicity to human cell lines at concentrations up to 100 µM, greater than 100-fold the minimum inhibitory concentration (MIC). Focused studies of one analog, RNP0012, which exhibited the most potent antimicrobial and inhibition of cellular RnpA activities revealed that the compound reduced bacterial burden in a murine model of S. aureus disease. Taken together, the results presented are expected to provide an early framework for optimization of next-generation of RnpA inhibitor analogues that may represent progenitors of a new class of antimicrobials.

Ventilator-associated pneumonia among ICU patients in WHO Southeast Asian region: A systematic review

Ventilator-associated pneumonia (VAP) is one of the most frequent ICU-acquired infections and a leading cause of death among patients in Intensive Care Unit (ICU). The South East Asian Region is a part of the world with limited health resources where infectious diseases are still underestimated. We aimed to review the literature in this part of the world to describe incidence, mortality and microbiological evidence of VAP and explore preventive and control strategies. We selected 24 peer-reviewed articles published from January 1, 2000 to September 1, 2020 from electronic databases and manual searching for observational studies among adult patients diagnosed with VAP expressed per thousand days admitted in ICU. The VAP rates ranged from 2.13 to 116 per thousand days, varying among different countries of this region. A significant rate of mortality was observed in 13 studies ranging from 16.2% to 74.1%. Gram negative organisms like Acinetobacter spp., Pseudomonas aeruginosa and Klebsiella pneumoniae and Gram-positive organisms like Staphylococcus aureus and Enterococcus species were frequently found. Our findings suggest an alarming situation of VAP among patients of most of the countries of this region with increasing incidence, mortality and antibiotic resistance. Thus, there is an urgent need for cost effective control and preventive measures like interventional studies and educational programs on staff training, hand hygiene, awareness on antibiotic resistance, implementation of antibiotic stewardship programs and appropriate use of ventilator bundle approach.

Incidence and Prognosis of Ventilator-Associated Pneumonia in Critically Ill Patients with COVID-19: A Multicenter Study

The primary objective of this multicenter, observational, retrospective study was to assess the incidence rate of ventilator-associated pneumonia (VAP) in coronavirus disease 2019 (COVID-19) patients in intensive care units (ICU). The secondary objective was to assess predictors of 30-day case-fatality of VAP. From 15 February to 15 May 2020, 586 COVID-19 patients were admitted to the participating ICU. Of them, 171 developed VAP (29%) and were included in the study. The incidence rate of VAP was of 18 events per 1000 ventilator days (95% confidence intervals [CI] 16–21). Deep respiratory cultures were available and positive in 77/171 patients (45%). The most frequent organisms were Pseudomonas aeruginosa (27/77, 35%) and Staphylococcus aureus (18/77, 23%). The 30-day case-fatality of VAP was 46% (78/171). In multivariable analysis, septic shock at VAP onset (odds ratio [OR] 3.30, 95% CI 1.43–7.61, p = 0.005) and acute respiratory distress syndrome at VAP onset (OR 13.21, 95% CI 3.05–57.26, p < 0.001) were associated with fatality. In conclusion, VAP is frequent in critically ill COVID-19 patients. The related high fatality is likely the sum of the unfavorable prognostic impacts of the underlying viral and the superimposed bacterial diseases.

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

BACKGROUND

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

OBJECTIVES

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

SEARCH METHODS

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

SELECTION CRITERIA

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

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane.

MAIN RESULTS

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

AUTHORS' CONCLUSIONS

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

Evaluation of a Loop-Mediated Isothermal Amplification Assay to Detect Carbapenemases Directly From Bronchoalveolar Lavage Fluid Spiked With Acinetobacter spp

Carbapenem-resistant Acinetobacter spp. mainly Acinetobacter baumannii are frequently causing nosocomial infections with high mortality. In this study, the efficacy of the Eazyplex® SuperBug Complete A system, based on loop-mediated isothermal amplification (LAMP), to detect the presence of carbapenemases in Acinetobacter spp. directly from bronchoalveolar lavage (BAL) samples was assessed. A total of 22 Acinetobacter spp. strains producing OXA-23, OXA-40, OXA-58, NDM, and IMP were selected. Eazyplex SuperBug Complete A kit, used with the Genie II device, is a molecular diagnostics kit that detects a selection of genes that express carbapenemases (bla KPC , bla NDM , bla VIM , bla OXA-48 , bla OXA-23 , bla OXA-40 , and bla OXA-58 ). Negative BAL samples were identified, McFarland solutions were prepared from each of the 22 Acinetobacter strains and serial dilutions in saline solution were made to finally spike BAL samples to a concentration of 102 and 103 CFU/ml. Fifteen concentrations out of the 44 tested out did not provide detection of the carbapenemase-producing gene, all but one being at the lowest concentration tested at 102 CFU/ml; therefore, the limit of sensitivity is 103 CFU/ml. This assay represents the kind of advantages that investing in molecular diagnostics brings to the clinical practice, allowing the identification of carbapenemases in less than 30 min with a sensitivity of 103 CFU/ml.

Microbiology of Ventilator-associated Pneumonia in a Tertiary Care Cancer Hospital

Background

Ventilator-associated pneumonia (VAP) is an important cause of healthcare-associated infections, resulting in prolonged hospitalization with increased morbidity and mortality. Knowledge of predominant local pathogens and their antimicrobial susceptibility patterns helps in selection of appropriate initial antibiotic therapy in these critical cases.

Aim and objective

The aim and objective of this study is to characterize the microbiology and antimicrobial susceptibility patterns of VAP isolates in a tertiary cancer center.

Materials and methods

This is a 4-year qualitative observational study carried out at a tertiary care cancer hospital in Mumbai. All nondirect bronchoalveolar lavage specimens from patients with a clinical suspicion of VAP sent from the critical care unit to the department of microbiology were processed as per standard laboratory procedures. All isolates were identified to species level and an antimicrobial susceptibility testing was performed by the Kirby–Bauer disk diffusion method and/or the VITEK 2 automated identification and susceptibility system, according to Clinical and Laboratory Standards Institute guidelines.

Results

The study comprised 1,074 patients: 710 (66.10%) men and 364 (33.90%) women. A total of 827 bacterial isolates were obtained with 780 (94.32%) gram-negative organisms and 47 (5.68%) gram-positive organisms; of which Acinetobacter baumannii (38.7%), Pseudomonas aeruginosa (17.5%), and Klebsiella pneumoniae (16.6%) were the commonest. Of gram-negative bacilli, multidrug-resistant organisms constituted 87.50% and were susceptible to colistin.

Conclusions

VAP is associated with pathogens, such as A. baumannii, P. aeruginosa, and K. pneumoniae in our setting. High rates of resistance to aminoglycosides, β-lactam-β-lactamase inhibitor combinations, and carbapenems were noted.

How to cite this article

Sangale A, Bhat V, Kelkar R, Biswas S. Microbiology of Ventilator-associated Pneumonia in a Tertiary Care Cancer Hospital. Indian J Crit Care Med 2021;25(4):421–428.

New perspectives in the antibiotic treatment of mechanically ventilated patients with infections from Gram-negatives

Introduction: Ventilator-associated pneumonia (VAP) is a common and potentially fatal complication of mechanical ventilation that is often caused by multidrug-resistant (MDR) Gram-negative bacteria (GNB). Despite the repurposing of older treatments and the novel antimicrobials, many resistance mechanisms cannot be confronted, and novel therapies are needed.Areas covered: We searched the literature for keywords regarding the treatment of GNB infections in mechanically ventilated patients. This narrative review presents new data on antibiotics and non-antibiotic approaches focusing on Phase 3 trials against clinically significant GNB that cause VAP.Expert opinion: Ceftazidime-avibactam, meropenem-vaborbactam, and imipenem-relebactam stand out as new options for infections by Klebsiella pneumoniae carbapenemase-producing bacteria, whereas ceftolozane-tazobactam adds therapeutic flexibility in Pseudomonas aeruginosa infections with multiple resistance mechanisms. Ceftazidime-avibactam and ceftolozane-tazobactam have relevant literature. Aztreonam-avibactam holds promise for the treatment of infections by metallo-β-lactamase (MBL)-producing organisms. Recently approved cefiderocol possesses an extended antibacterial spectrum, including KPC- and MBL-producers. However, recently published data have toned down optimism about treating VAP caused by carbapenem-resistant Acinetobacter baumannii. For the latter, eravacycline may provide additional hope, pending pertinent data. Non-antibiotic treatments currently being considered as adjunct therapeutic approaches are welcome. Nevertheless, they will hopefully substitute current antimicrobials in the future.

A bibliometric analysis of income and cardiovascular disease: Status, Hotspots, Trends and Outlook

BACKGROUND

Income is 1 of the socio-economic indicators and could directly influence the health outcomes of cardiovascular disease (CVD). The relationship between income and CVD has attracted more and more scholars' attention in the past 20 years.

METHODS

To study the current research dynamics of this field, a bibliometric analysis was conducted to evaluate the publications from 1990 to 2018 based on the Science Citation Index Expanded database. By using the Derwent Date Analyzer software, the following aspects were explored: RESULTS:: The USA ranked first in this field, followed by UK and Canada in terms of number of publications. As for institutions, Harvard University took the leading place in the number of publications, as well as the h-index. Plos One had the most publications and "health" was the most frequent used keyword. The leading research area was "public environmental occupational health".

CONCLUSIONS

In conclusion, the elderly, the children and the puerpera were the main study population in this field and "disease prevention" was the main study direction. The most concerned health issues in this field were "obesity" and "diet". There might be a lack of articles that explore the associations between income and CVD with a global perspective. Articles on this content are urgently warranted.