"Don, doff, discard" to "don, doff, decontaminate"-FFR and mask integrity and inactivation of a SARS-CoV-2 surrogate and a norovirus following multiple vaporised hydrogen peroxide-, ultraviolet germicidal irradiation-, and dry heat decontaminations.

BACKGROUND: As the SARS-CoV-2 pandemic accelerates, the supply of personal protective equipment remains under strain. To combat shortages, re-use of surgical masks and filtering facepiece respirators has been recommended. Prior decontamination is paramount to the re-use of these typically single-use only items and, without compromising their integrity, must guarantee inactivation of SARS-CoV-2 and other contaminating pathogens. AIM: We provide information on the effect of time-dependent passive decontamination (infectivity loss over time during room temperature storage in a breathable bag) and evaluate inactivation of a SARS-CoV-2 surrogate and a non-enveloped model virus as well as mask and respirator integrity following active multiple-cycle vaporised hydrogen peroxide (VHP), ultraviolet germicidal irradiation (UVGI), and dry heat (DH) decontamination. METHODS: Masks and respirators, inoculated with infectious porcine respiratory coronavirus or murine norovirus, were submitted to passive decontamination or single or multiple active decontamination cycles; viruses were recovered from sample materials and viral titres were measured via TCID50 assay. In parallel, filtration efficiency tests and breathability tests were performed according to EN standard 14683 and NIOSH regulations. RESULTS AND DISCUSSION: Infectious porcine respiratory coronavirus and murine norovirus remained detectable on masks and respirators up to five and seven days of passive decontamination. Single and multiple cycles of VHP-, UVGI-, and DH were shown to not adversely affect bacterial filtration efficiency of masks. Single- and multiple UVGI did not adversely affect respirator filtration efficiency, while VHP and DH induced a decrease in filtration efficiency after one or three decontamination cycles. Multiple cycles of VHP-, UVGI-, and DH slightly decreased airflow resistance of masks but did not adversely affect respirator breathability. VHP and UVGI efficiently inactivated both viruses after five, DH after three, decontamination cycles, permitting demonstration of a loss of infectivity by more than three orders of magnitude. This multi-disciplinal approach provides important information on how often a given PPE item may be safely reused.

The role of bacterial colonization of ventilator circuit in development of ventilator associated pneumonia in ICU of Medical Center Hospital in Tripoli, Libya

Introduction: In mechanically ventilated patients, ventilator-associated pneumonia (VAP) is a major cause of prolonged hospitalization with increased morbidity and mortality. There is a lack of studies on the relationship between bacterial colonization of the ventilator circuit (VC) and VAP. This study aimed to investigate the role of bacterial colonization of VC in the development of VAP and identify antibiotic susceptibility trends for isolated strains. Methods: A prospective study of the bacterial culture has been performed between February 2021 to March 2021 on a total of 100 mechanically ventilated patients, (n =50) samples have been obtained from patient's lower respiratory tract (LRT) and (n =50) were taken from mechanical ventilator equipment VC. Paired samples of bacteria isolated from VC and LRT, where VC was colonized before LRT. Results: A total of 58 samples were cultured positively, while 42 specimens showed negative bacterial growth. However, there was no substantial difference in comparing between the bacterial colonization of the ventilator system and the patient samples. Most isolated organisms were gram-negative bacteria which were found in the ventilator circuit with 26 (68.4%), and 14 (70%) in patient's LRT. Gram-positive was detected in 12 (31.6%) and 6 (30%) of the ventilator circuit, and patient's LRT, respectively. The predominant bacterial type was Acinetobacter baumannii organism at the VC with 10 (26.3%) and LRT at 4 (20%) followed by Klebsiella pneumoniae (8 (21.1%) in VC and 4 (20%) in LRT). Moreover, A. baumannii showed a full resistance to amoxicillin and the first generation of cephalosporins, while the other bacterial types were resistant to the most antibiotics used in this research (AU)

Quantitative UV-C dose validation with photochromic indicators for informed N95 emergency decontamination.

With COVID-19 N95 shortages, frontline medical personnel are forced to reuse this disposable-but sophisticated-multilayer respirator. Widely used to decontaminate nonporous surfaces, UV-C light has demonstrated germicidal efficacy on porous, non-planar N95 respirators when all surfaces receive ≥1.0 J/cm2 dose. Of utmost importance across disciplines, translation of empirical evidence to implementation relies upon UV-C measurements frequently confounded by radiometer complexities. To enable rigorous on-respirator measurements, we introduce a photochromic indicator dose quantification technique for: (1) UV-C treatment design and (2) in-process UV-C dose validation. While addressing outstanding indicator limitations of qualitative readout and insufficient dynamic range, our methodology establishes that color-changing dosimetry can achieve the necessary accuracy (>90%), uncertainty (<10%), and UV-C specificity (>95%) required for UV-C dose measurements. In a measurement infeasible with radiometers, we observe a striking ~20× dose variation over N95s within one decontamination system. Furthermore, we adapt consumer electronics for accessible quantitative readout and use optical attenuators to extend indicator dynamic range >10× to quantify doses relevant for N95 decontamination. By transforming photochromic indicators into quantitative dosimeters, we illuminate critical considerations for both photochromic indicators themselves and UV-C decontamination processes.

The role of bacterial colonization of ventilator circuit in development of ventilator-associated pneumonia: a prospective observational cohort study.

OBJECTIVES: Ventilator-associated pneumonia (VAP) is a significant cause of prolonged hospital stay and increased mortality in mechanically ventilated children. Studies of the relationship between bacterial colonization of ventilator circuits (VCs) and VAP are lacking. This study aimed to investigate the role of bacterial colonization of VCs in the development of VAP, and to provide evidence for preventing VAP. METHODS: Mechanically ventilated patients admitted to the paediatric intensive care unit of a teaching hospital in China from October 2018 to November 2019 were enrolled. Specimens were collected from the VC and the patient's lower respiratory tract (LRT) for bacterial culture. Paired bacteria isolated from the VC and the patient's LRT, where colonization of the VC preceded that of the LRT, were evaluated for relatedness using pulsed field gel electrophoresis (PFGE). RESULTS: A total of 114 patients were included; the incidence rate of VAP was 28.1% (32/114). A total of 1368 samples were collected from VCs; 16% had positive bacterial culture. There was no significant difference in bacterial colonization of VCs between VAP and non-VAP. In 13 patients, the LRT and VC were concurrently colonized with the same bacteria, where colonization of the VC occurred before colonization of the patient's LRT. PFGE results demonstrated high correlation between bacteria from the LRT and VC in 11 patients. Among 114 mechanically ventilated children, VAP caused by bacteria from the VC occurred in six patients, accounting for 18.8% (6/32) of the overall VAP rate in this study. DISCUSSION: Bacterial colonization of the VC is a significant cause of VAP development in mechanically ventilated children. Preventive strategies for early identification and decontamination measures for contaminated VC may play a key role in preventing VAP.

The etiology of neonatal pneumonia, complicated by bronchopulmonary dysplasia.

BACKGROUND: The frequency of bronchopulmonary dysplasia (BPD) in preterm infants with a "ventilator-associated" pneumonia (VAP) ranges between 7 to 50%. OBJECTIVE: To investigate the features of the etiological structure of neonatal pneumonia complicated by BPD, and to determine the sensitivity of pathogens to antibiotics. METHODS: A retrospective chart review of 194 preterm infants with VAP, birth weight from 780 to 2820 g and gestational age from 27 to 37 weeks was conducted. A microbiological study of washings from the respiratory tract was conducted by standard qualitative and quantitative methods. RESULTS: Respiratory tract infections caused by E. coli (with hemolytic properties), Enterococcus spp. (with hemolytic properties), Pseudomonas aeruginosa, Stenotrophomonas maltophilia, various types of mycoplasmas, Staphylococcus aureus, and Candida krusei were found 4- 13 times more frequent in preterm infants with BPD than in preterm infants without BPD and more mature infants with or without this complication. BPD developed 7- 11 times more frequent in preterm infants with prolonged VAP and change in pathogens than in preterm infants with VAP without change of agent. BPD developed 5- 7 times more frequent in preterm infants with the association of pathogens than in preterm infants with a monoinfection. Massive colonization of respiratory tract pathogens by 1- 3 days of life (lg4 colony forming units in 1 ml and above) was an unfavorable prognostic factor for the development of VAP, complicated by BPD. CONCLUSION: The reduction in the frequency of BPD is might be possible with timeous and adequate antibacterial therapy of VAP.

Comparison of GeneXpert MRSA/SA ETA assay with semi-quantitative and quantitative cultures and nuc gene-based qPCR for detection of Staphylococcus aureus in endotracheal aspirate samples.

Introduction: Staphylococcus aureus (S. aureus) is a common cause of ventilator-associated pneumonia. Rapid and accurate detection of lower respiratory tract colonization and/or infection with S. aureus may inform targeted preventive and therapeutic strategies. To investigate this, we compared semi-quantitative (SQ)-culture results from 79 endotracheal aspirates (ETA) collected from mechanically-ventilated patients, to two culture and two non-culture-based methods for detection of S. aureus. Methods: ETA analyzed by routine SQ-culture on blood and colistin-nalidixic-acid agar was compared to: (i) quantitative (Q-) culture on chromogenic COLOREX™ Staph aureus; (ii) enrichment in brain-heart-infusion broth followed by plating on blood agar and COLOREX™; (iii) nuc-based TaqMan qPCR, and (iv) GeneXpert MRSA/SA ETA assay. Results: Of the 79 ETA samples analyzed by SQ-culture, 39 samples were positive, and 40 negative for S. aureus. Two samples negative for S. aureus by SQ-culture were, however, S. aureus-positive by the other four methods and were considered positive. Appending these two samples as positive in the SQ-culture results, sensitivities-specificities for Q-culture, enrichment-culture, TaqMan qPCR and GeneXpert were 100-95, 100-92, 100-53% and 100% - 100, respectively. The lower specificities of Q-culture, enrichment-culture, and TaqMan qPCR was because of their higher sensitivities, although TaqMan qPCR also detected S. aureus-specific extracellular DNA. Conclusion: This first evaluation of the GeneXpert MRSA/SA ETA assay with ETA samples found it to be highly sensitive, specific, user-friendly (hands-on time ~ 5 min.), and rapid (~ 66 min. assay time). Where this equipment is not available, we recommend implementing more sensitive culture-based methods for improved S. aureus detection in ETA samples.

Epidemiology of ICU-acquired pneumonia.

PURPOSE OF REVIEW: Review of the epidemiology of ICU-acquired pneumonia, including both ventilator-associated pneumonia (VAP) and hospital-acquired pneumonia (HAP) in nonventilated ICU patients, with critical review of the most recent literature in this setting. RECENT FINDINGS: The incidence of ICU-acquired pneumonia, mainly VAP has decrease significantly in recent years possibly due to the generalized implementation of preventive bundles. However, the exact incidence of VAP is difficult to establish due to the diagnostic limitations and the methods employed to report rates. Incidence rates greatly vary based on the studied populations. Data in the literature strongly support the relevance of intubation, not ventilatory support, in the development of HAP in ICU patients, but also that the incidence of HAP in nonintubated patients is not negligible. Despite the fact of a high crude mortality associated with the development of VAP, the overall attributable mortality of this complication was estimated in 13%, with higher mortality rates in surgical patients and those with mid-range severity scores at admission. Mortality is consistently greatest in patients with HAP who require intubation, slightly less in VAP, and least for nonventilated HAP. The economic burden of ICU acquired pneumonia, particularly VAP, is important. The increased costs are mainly related to the longer periods of ventilatory assistance and ICU and hospital stays required by these patients. However, the different impact of VAP on economic burden among countries is largely dependent on the different costs associated with heath care. SUMMARY: VAP has significant impact on mortality mainly in surgical patients and those with mid-range severity scores at admission. The economic burden on ICU-acquired pneumonia depends mainly on the increased length of stay of these patients.

Evaluating the Efficacy of Nanosil Mouthwash on the Preventing Pulmonary Infection in Intensive Care Unit: a Randomized Clinical Trial.

INTRODUCTION: Oral and Oro-pharynx colonization and Micro-aspiration of discharges are two important processes in ventilator-associated pneumonia (VAP). So, this study design to investigated the preventive effect of oral decontamination program by Nanosil mouthwash on incidence of ventilator-associated pneumonia. METHODS: 80 newly hospitalized patients who admitted in intensive care unit (ICU) of Amin Medical Education Center were enrolled to a randomized clinical trial study. Patients were randomly divided into two equal groups. In the intervention group, a multi-stage oral decontamination program was performed by using Nanosil mouthwash three times a day, and in the control group oral decontamination was performed by Chlorhexidine 0.12% with same method. The oral decontamination program was continuing for five days. The VAP was diagnosed with a version of modified clinical pulmonary infection scale (MCPIS) on the first and fifth days. RESULTS: In compare the case and control groups, there wasn't observed significant difference in age, gender, underling disease, smoking, and primary mean scores of MCPIS, sequential organ failure assessment (SOFA) and Glasgow coma scale (GCS) (P>0.05). In the both groups, the mean scores of SOFA and GCS were significantly improve in fifth day (P<0.05). After five days follow up, the mean score of MCPIS (1.2±0.1 vs. 3.5±0.3, P<0.001) and pneumonia rate (2.7% vs. 23.7%, P=0.008) were significantly lower in case group. But, the mortality rate was same in both groups (P>0.05). DISCUSSION: The use of oral care program with Nanosil mouthwash is better than Chlorhexidine for the prevention of VAP in patients who admitted in ICU.

Outbreak of hypervirulent Klebsiella pneumoniae harbouring blaVIM-2 among mechanically-ventilated drug-poisoning patients with high mortality rate in Iran.

OBJECTIVES: Carbapenem-resistant Klebsiella pneumoniae infections are associated with increased rates of treatment failure and death. Several studies have reported isolates with a combined hypervirulent and antimicrobial-resistant phenotype. METHODS: In this study, the molecular characteristics of hypervirulent K. pneumoniae (hvKP) isolated from mechanically-ventilated patients admitted to a toxicological intensive care unit (ICU) in Tehran, Iran, were examined. String test, antimicrobial susceptibility testing, virulence factors analysis and plasmid replicon typing were performed. The clonal relatedness of the isolates was analysed by pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST). RESULTS: hvKP accounted for 9.4% (5/53) of K. pneumoniae isolated from ventilator-associated pneumonia among patients admitted to the ICU with acute drug poisoning. The mortality rate was 7.5% (4/53) among K. pneumoniae-infected patients. All fatal K. pneumoniae were hvKP isolates, were resistant to imipenem and harboured an aacA7, blaVIM-2 and dhfrI cassette arrangement in a class 1 integron. The isolates were shown to be ST23 (Pasteur scheme) and exhibited similar PFGE patterns. Plasmid analysis revealed a class 1 integron harbouring blaVIM-2 located on an ca. 45-kb IncN plasmid. CONCLUSION: Here we describe the emergence of VIM-2-producing hvKP serotype K1/ST23 in an outbreak with high mortality in a hospital toxicological ICU. It appears that we must alert and prepare the hospital's surveillance system for the appearance, expansion and clinical importance of new K. pneumoniae clones associated with high antimicrobial resistance and robust virulence capabilities.

[Effective management of an outbreak with multiresistent Klebsiella pneumoniae in a neurorehabilitation unit]. / Effektives Management eines Ausbruchs mit multiresistenten Klebsiella pneumoniae in der Neurorehabilitation.

BACKGROUND: In addition to acute care hospitals, rehabilitation centres are increasingly confronted with multi-resistant pathogens. Long durations of stay and intensive treatments impose special hygienic challenges. MATERIAL AND METHODS: We investigated an extended spectrum beta-lactamase-Klebsiella pneumoniae (ESBL-K. pneumoniae) outbreak in a neurorehabilitation centre. We defined confirmed cases as patients who stayed in the centre during the outbreak period and from whom ESBL-K. pneumoniae was isolated with the outbreak sequence type. Probable cases had an epidemiological link to at least one confirmed case but no isolate for typing. Next generation sequencing (NGS) was performed on 53 isolates from patients. Environmental sampling was performed. Systematic microbiological screening was implemented and ESBL-K. pneumoniae-positive patients were cohorted in a designated ward. RESULTS: We identified 30 confirmed and 6 probable cases. NGS revealed three genetic clusters: Cluster 1 - the outbreak cluster - with isolates of 30 cases (sequence type ST15), Cluster 2 with 7 patients (ST405) and Cluster 3 with 8 patients (ST414). In two patients, the outbreak strain developed further antibiotic resistance, one with colistin resistance and the other carbapenem resistance. The outbreak ceased after strict isolation measures. DISCUSSION: Epidemiology and NGS results paired with the effectiveness of cohorting suggest that transmission occurred mainly from person to person in this outbreak. There was an apparent association of the probability to acquire ESBL-K. pneumoniae and treatment intensity, whereas infection rate was related to morbidity. The identification of the outbreak clone and additional clusters plus the development of additional antibiotic resistance shows the relevance of NGS and highlights the need for timely and efficient outbreak management.

Potential risk for bacterial contamination in conventional reused ventilator systems and disposable closed ventilator-suction systems.

BACKGROUND: Few studies have investigated the difference in bacterial contamination between conventional reused ventilator systems and disposable closed ventilator-suction systems. The aim of this study was to investigate the bacterial contamination rates of the reused and disposable ventilator systems, and the association between system disconnection and bacterial contamination of ventilator systems. METHODS: The enrolled intubated and mechanically ventilated patients used a conventional reused ventilator system and a disposable closed ventilator-suction system, respectively, for a week; specimens were then collected from the ventilator circuit systems to evaluate human and environmental bacterial contamination. The sputum specimens from patients were also analyzed in this study. RESULTS: The detection rate of bacteria in the conventional reused ventilator system was substantially higher than that in the disposable ventilator system. The inspiratory and expiratory limbs of the disposable closed ventilator-suction system had higher bacterial concentrations than the conventional reused ventilator system. The bacterial concentration in the heated humidifier of the reused ventilator system was significantly higher than that in the disposable ventilator system. Positive associations existed among the bacterial concentrations at different locations in the reused and disposable ventilator systems, respectively. The predominant bacteria identified in the reused and disposable ventilator systems included Acinetobacter spp., Bacillus cereus, Elizabethkingia spp., Pseudomonas spp., and Stenotrophomonas (Xan) maltophilia. CONCLUSIONS: Both the reused and disposable ventilator systems had high bacterial contamination rates after one week of use. Disconnection of the ventilator systems should be avoided during system operation to decrease the risks of environmental pollution and human exposure, especially for the disposable ventilator system. TRIAL REGISTRATION: ClinicalTrials.gov PRS / NCT03359148.

Prior antimicrobial therapy duration influences causative pathogens identification in ventilator-associated pneumonia.

OBJECTIVE: To determine whether prior antimicrobial therapy, divided in recent or current antibiotic treatment, influences the identification rate and/or the type of causative pathogens in patients with suspected episodes of ventilator-acquired pneumonia. DESIGN: Monocentric retrospective study. SETTING: Intensive car unit in a universitary hospital. PATIENTS: 230 episodes of ventilator-associated pneumonia with a Clinical Pulmonary Infection Score≥6 were retrospectively evaluated. Based on the antimicrobial treatment regimen, we defined 3 groups: the no antimicrobial treatment group (VAP is suspected in patients that has never received antibiotics during the last 90days), group 2: the current antimicrobial therapy (VAP is suspected under antimicrobial therapy) and group 3: the recent antimicrobial therapy (VAP is suspected whereas an antimicrobial treatment has been used during the last 90days but discontinued for >24h). INTERVENTION: Bacteriologic analysis using a protected distal sampling with microscopic examination, culture and microbial identification using MALDI-TOF. MEASUREMENTS AND MAIN RESULTS: Suspected episodes of VAP were sorted as follow: 70 suspected episodes in the no antimicrobial therapy group, 106 suspected episodes in the current antimicrobial therapy group and 54 suspected episodes in the recent antimicrobial therapy group. The rate of positive culture was significantly lower in the current antimicrobial treatment group (group 2) when compared to the recent (group 3) and to the no antimicrobial treatment groups (group 1) (42%, 68% and 86%, respectively). When compared to the recent antibiotherapy group, we observed that current antibiotherapy was significantly associated with a higher rate of MDR positive culture, mainly due to higher rate of MDR Pseudomonas aeruginosa. CONCLUSION: In patients with a high probability of VAP, current but not recent antibiotic use is associated with a lower rate of positive culture with a higher proportion of MDR pathogens, mostly MDR Pseudomonas aeruginosa.

Mechanical ventilator as a major cause of infection and drug resistance in intensive care unit.

Ventilator-associated pneumonia (VAP) is the most frequent infection in intensive care units (ICU). It is associated with high rates of long morbidity and mortality. Management of a case of VAP is often said to add $40,000 to hospital costs USA. All these data directed our interest to study the etiology, risk factors, and antibiotic susceptibility patterns of VAP in ICU of Tanta University Hospital. This study included 36 cases of VAP. Endotracheal aspirates were obtained from all cases and microbiologically analyzed. Samples were collected over 1 year. Forty-two strains were isolated from 28 cases, while eight cases showed no bacterial growth. The most frequent organism was Staphylococcus aureus (30.95%), followed by Acinetobacter baumannii and Pseudomonas aeruginosa (21.43% for each), and the least common was Staphylococcus epidermidis (2.38%). Multi-drug resistance was detected in (50%) of the isolated bacteria in this study. Imipenem, amikacin, linezolid, vancomycin, and levofloxacin are recommended to be the most effective drugs in management of VAP. VAP is a serious problem in ICU carrying many risks for the patient live. Regimens of empirical treatment should take in consideration the update in the bacterial etiology and antibiotic susceptibility patterns of VAP.

Association between pathogens from tracheal aspirate and oral biofilm of patients on mechanical ventilation.

The aim of this study was to detect possible associations between respiratory pathogens from tracheal aspirate and oral biofilm samples in intubated patients in an intensive care unit (ICU), and to identify the most common respiratory pathogens in oral biofilm, particularly in patients that developed ventilator-associated pneumonia (VAP). Two oral biofilm samples were collected from the tongue of intubated patients (at admission and after 48 hours) and analyzed by culture with the Antibiotic Sensitivity Test. The results from the tongue biofilm samples were compared with the tracheal secretions samples. A total of 59.37% of patients exhibited the same species of pathogens in their tracheal aspirate and oral biofilm, of which 8 (42.1%) developed VAP, 10 (52.63%) did not develop pneumonia and one (5.26%) had aspiration pneumonia. There was a statistically significant association between presence of microorganisms in the tracheal and mouth samples for the following pathogens: Klebsiella pneumoniae, Candida albicans, Pseudomonas aeruginosa, Enterobacter gergoviae, Streptococcus spp and Serratia marcescens (p < 0.05). Pathogens that are present in tracheal aspirates of intubated patients can be detected in their oral cavity, especially in those who developed VAP or aspiration pneumonia. Thus, the results indicate that an improved oral care in these patients could decrease ICU pneumonia rates.

Streptococcus sp. in neonatal endotracheal tube biofilms is associated with ventilator-associated pneumonia and enhanced biofilm formation of Pseudomonas aeruginosa PAO1.

Ventilator-associated pneumonia (VAP) is a serious complication of mechanical ventilation leading to high morbidity and mortality among intubated neonates in neonatal intensive care units (NICUs). Endotracheal tube (ETT) biofilm flora were considered to be responsible for the occurrence of VAP as a reservoir of pathogens. However, regarding neonates with VAP, little is known about the complex microbial signatures in ETT biofilms. In the present study, a culture-independent approach based on next generation sequencing was performed as an initial survey to investigate the microbial communities in ETT biofilms of 49 intubated neonates with and without VAP. Our results revealed a far more complex microflora in ETT biofilms from intubated neonates compared to a previous culture-based study. The abundance of Streptococci in ETT biofilms was significantly related to the onset of VAP. By isolating Streptococci in ETT biofilms, we found that Streptococci enhanced biofilm formation of the common nosocomial pathogen Pseudomonas aeruginosa PAO1 and decreased IL-8 expression of airway epithelia cells exposed to the biofilm conditioned medium of PAO1. This study provides new insight into the pathogenesis of VAP among intubated neonates. More studies focusing on intubated neonates are warranted to develop strategies to address this important nosocomial disease in NICUs.

The clinical significance of pneumonia in patients with respiratory specimens harbouring multidrug-resistant Pseudomonas aeruginosa: a 5-year retrospective study following 5667 patients in four general ICUs.

Pseudomonas aeruginosa is the leading cause of pneumonia in intensive care units (ICUs), with multidrug-resistant (MDR) strains posing a serious threat. The aim of this study was to assess the clinical relevance of MDR Pseudomonas isolates in respiratory clinical specimens. A 5-year retrospective observational study in four medical-surgical ICUs from a referral hospital was carried out. Of 5667 adults admitted to the ICU, 69 had MDR-PA in respiratory samples: 31 were identified as having pneumonia (HAP/VAP): 21 ventilator-associated pneumonia (VAP) and ten hospital-acquired pneumonia (HAP). Twenty-one (67.7%) adults with MDR-PA HAP/VAP died after a median of 4 days (18 of the 21 deaths within 8 days), compared with one (2.6%) without pneumonia at day 8. In a Cox proportional regression model, MDR-PA pneumonia was an independent variable [adjusted hazard ratio (aHR) 5.92] associated with 30-day ICU mortality. Most strains (85.1%) were susceptible to amikacin and colistin. Resistance to beta-lactams (third-generation cephalosporins and piperacillin-tazobactam) ranged from 44.1% to 45.3%. Meropenem showed poor overall activity (MIC[50/90] 16/32 mg/dL), with 47.0% having a minimum inhibitory concentration (MIC) breakpoint >8 mg/L. Twenty-four (77.4%) HAP/VAP episodes received inappropriate empirical therapy. Although empirical combination therapy was associated with less inappropriate therapy than monotherapy (16.7% vs. 88.3%, p < 0.01), there was no difference in survival (30% vs. 33.3%, p = 0.8). Pneumonia was identified in one-third of adult ICU patients harbouring MDR-PA in respiratory clinical specimens. These patients have a 6-fold risk of (early) death compared to ventilator-associated tracheobronchitis (VAT) and respiratory colonisation. New antibiotics and adjuvant therapies are urgently needed to prevent and treat MDR-PA HAP/VAP.

Risk factors for mortality in ventilator-associated tracheobronchitis: a case-control study.

Objective: To describe the microbiological characteristics and to assess the risk factors for mortality of ventilator-associated tracheobronchitis in a case-control study of intensive care patients. Methods: This case-control study was conducted over a 6-year period in a 40-bed medical-surgical intensive care unit in a tertiary care, private hospital in São Paulo, Brazil. Case patients were identified using the Nosocomial Infection Control Committee database. For the analysis of risk factors, matched control subjects were selected from the same institution at a 1:8.8 ratio, between January 2006 and December 2011. Results: A total of 40 episodes of ventilator-associated tracheobronchitis were evaluated in 40 patients in the intensive care unit, and 354 intensive care patients who did not experience tracheobronchitis were included as the Control Group. During the 6-year study period, a total of 42 organisms were identified (polymicrobial infections were 5%) and 88.2% of all the microorganisms identified were Gram-negative. Using a logistic regression model, we found the following independent risk factors for mortality in ventilator-associated tracheobronchitis patients: Acute Physiology and Chronic Health Evaluation I score (odds ratio 1.18 per unit of score; 95%CI: 1.05-1.38; p=0.01), and duration of mechanical ventilation (odds ratio 1.09 per day of mechanical ventilation; 95%CI: 1.03-1.17; p=0.004). Conclusion: Our study provided insight into the risk factors for mortality and microbiological characteristics of ventilator-associated tracheobronchitis.

Objetivo: Descrever as características microbiológicas e avaliar os fatores de risco para mortalidade na traqueobronquite associada à ventilação mecânica em um estudo caso-controle de pacientes de terapia intensiva. Métodos: Estudo realizado ao longo de 6 anos em uma unidade de terapia intensiva médico-cirúrgica de 40 leitos, em um hospital privado e de nível terciário em São Paulo, Brasil. O Grupo Caso foi identificado usando o banco de dados da Comissão de Controle de Infecção Hospitalar. O Grupo Controle foi pareado na proporção de 1:8,8 entre janeiro de 2006 e dezembro de 2011. Resultados: Quarenta episódios de traqueobronquites associadas à ventilação foram avaliados em 40 pacientes na unidade de terapia intensiva, e 354 pacientes não apresentaram traqueobronquite Grupo Controle. Foram identificados 42 microrganismos (dos quais 5% foram infecções polimicrobianas), sendo que 88,2% de todos os microrganismos eram bactérias Gram-negativas. Usando um modelo de regressão logística, encontramos os seguintes fatores de risco independentes para mortalidade em pacientes com traqueobronquites associadas à ventilação: pontuação da Acute Physiology and Chronic Health Evaluation I (odds ratio 1,18 por uma unidade de pontuação; IC95%: 1,05-1,38; p=0,01) e duração da ventilação mecânica (odds ratio 1,09 por dia de ventilação mecânica; IC95%: 1,03-1,17; p=0,004). Conclusão: Nosso estudo forneceu informações sobre os fatores de risco para mortalidade e características microbiológicas da traqueobronquite associada à ventilação mecânica.

Suspicious outbreak of ventilator-associated pneumonia caused by Burkholderia cepacia in a surgical intensive care unit.

BACKGROUND: We reviewed Burkholderia cepacia infections in a hospital from 2013-2016 to report a suspicious outbreak that occurred in a surgical intensive care unit in 2015, and to outline the infection control measures adopted thereafter. METHODS: Review of the health care-associated infection data regarding B cepacia via the surveillance system, hospital information system, electronic medical records, and laboratory information system together with the outbreak investigation was managed by the health care-associated infection control team. RESULTS: During June 1-14, 2015, 4 cases of ventilator-associated pneumonia (VAP) were identified; B cepacia was isolated from endotracheal aspirate samples. On June 16, 120 environmental samples were collected and analyzed for microbiologic differentiation. Thirteen strains of B cepacia were prominently found in the expiratory blocks of ventilators, revealing the biocontamination source. After chemical disinfection without damaging ventilator components, repeat microbiologic testing of random ventilator samples yielded negative results until July 30, 2015. Retrospective data showed that isolation rates of B cepacia strains had increased since 2014. Although the resistance phenotype of these strains varied slightly, they exhibited similar patterns of antibiotic susceptibility. CONCLUSIONS: Routine cleaning and disinfection of ventilators, in addition to an intervention bundle, should form part of an integrated VAP prevention and management approach.

Risk factors for mortality in ventilator-associated tracheobronchitis: a case-control study / Fatores de risco para mortalidade em traqueobronquite associada à ventilação mecânica: estudo caso-controle

ABSTRACT Objective To describe the microbiological characteristics and to assess the risk factors for mortality of ventilator-associated tracheobronchitis in a case-control study of intensive care patients. Methods This case-control study was conducted over a 6-year period in a 40-bed medical-surgical intensive care unit in a tertiary care, private hospital in São Paulo, Brazil. Case patients were identified using the Nosocomial Infection Control Committee database. For the analysis of risk factors, matched control subjects were selected from the same institution at a 1:8.8 ratio, between January 2006 and December 2011. Results A total of 40 episodes of ventilator-associated tracheobronchitis were evaluated in 40 patients in the intensive care unit, and 354 intensive care patients who did not experience tracheobronchitis were included as the Control Group. During the 6-year study period, a total of 42 organisms were identified (polymicrobial infections were 5%) and 88.2% of all the microorganisms identified were Gram-negative. Using a logistic regression model, we found the following independent risk factors for mortality in ventilator-associated tracheobronchitis patients: Acute Physiology and Chronic Health Evaluation I score (odds ratio 1.18 per unit of score; 95%CI: 1.05-1.38; p=0.01), and duration of mechanical ventilation (odds ratio 1.09 per day of mechanical ventilation; 95%CI: 1.03-1.17; p=0.004). Conclusion Our study provided insight into the risk factors for mortality and microbiological characteristics of ventilator-associated tracheobronchitis.

RESUMO Objetivo Descrever as características microbiológicas e avaliar os fatores de risco para mortalidade na traqueobronquite associada à ventilação mecânica em um estudo caso-controle de pacientes de terapia intensiva. Métodos Estudo realizado ao longo de 6 anos em uma unidade de terapia intensiva médico-cirúrgica de 40 leitos, em um hospital privado e de nível terciário em São Paulo, Brasil. O Grupo Caso foi identificado usando o banco de dados da Comissão de Controle de Infecção Hospitalar. O Grupo Controle foi pareado na proporção de 1:8,8 entre janeiro de 2006 e dezembro de 2011. Resultados Quarenta episódios de traqueobronquites associadas à ventilação foram avaliados em 40 pacientes na unidade de terapia intensiva, e 354 pacientes não apresentaram traqueobronquite Grupo Controle. Foram identificados 42 microrganismos (dos quais 5% foram infecções polimicrobianas), sendo que 88,2% de todos os microrganismos eram bactérias Gram-negativas. Usando um modelo de regressão logística, encontramos os seguintes fatores de risco independentes para mortalidade em pacientes com traqueobronquites associadas à ventilação: pontuação da Acute Physiology and Chronic Health Evaluation I (odds ratio 1,18 por uma unidade de pontuação; IC95%: 1,05-1,38; p=0,01) e duração da ventilação mecânica (odds ratio 1,09 por dia de ventilação mecânica; IC95%: 1,03-1,17; p=0,004). Conclusão Nosso estudo forneceu informações sobre os fatores de risco para mortalidade e características microbiológicas da traqueobronquite associada à ventilação mecânica.