Ventilator-associated pneumonia. European Task Force on ventilator-associated pneumonia

A Narrative Review on the Approach to Antimicrobial Use in Ventilated Patients with Multidrug Resistant Organisms in Respiratory Samples—To Treat or Not to Treat? That Is the Question

Multidrug resistant organisms (MDRO) are commonly isolated in respiratory specimens taken from mechanically ventilated patients. The purpose of this narrative review is to discuss the approach to antimicrobial prescription in ventilated patients who have grown a new MDRO isolate in their respiratory specimen. A MEDLINE and PubMed literature search using keywords “multidrug resistant organisms”, “ventilator-associated pneumonia” and “decision making”, “treatment” or “strategy” was used to identify 329 references as background for this review. Lack of universally accepted diagnostic criteria for ventilator-associated pneumonia, or ventilator-associated tracheobronchitis complicates treatment decisions. Consideration of the clinical context including signs of respiratory infection or deterioration in respiratory or other organ function is essential. The higher the quality of respiratory specimens or the presence of bacteremia would suggest the MDRO is a true pathogen, rather than colonization, and warrants antimicrobial therapy. A patient with higher severity of illness has lower safety margins and may require initiation of antimicrobial therapy until an alternative diagnosis is established. A structured approach to the decision to treat with antimicrobial therapy is proposed.

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.

Frequency of Ventilator Associated Pneumonias in Patients in the Intensive Care Unit

INTRODUCTION

Ventilator associated pneumonia (VAP) is defined as nosocomial pneumonia in patients who have mechanical ventilation (MV) for more than 48 hours. The diagnosis of VAP is based on radiological-microbiological examinations. In the United States, the Centers for Disease Control and Prevention (CDC) and the National Health Care Network (NHSN) have an incidence of VAP of 5.8% per 1,000 days on mechanical ventilator.

AIM

In this study, we had an aim to determine the occurrence of ventilator-associated pneumonia (VAP) in patients with MV who were hospitalized in the intensive care unit.

METHOD

The study was retrospective, clinical, conducted in the period from January 1, 2016 until December 31, 2016. In a one-year period, 719 patients of both sex, aged 14 to 91, were hospitalized in the intensive care unit of the Clinic for Anesthesia and Resuscitation of the University Clinical Center in Sarajevo. The study included 250 patients of both sex who had respiratory support with mechanical ventilator. No patient was excluded from the study. As a confirmation of VAP, we used microbiological reports from the patient history documentation. The results were presented statistically through tables and graphs, numerically, by a percentage, and by a mean value with standard deviation.

RESULTS

Out of the 719 hospitalized patients, 250 or 34.8% underwent controlled ventilation. In 103 or 41.2% of patients some form of pneumonia was confirmed microbiologically. An average patient age on controlled ventilation was 60.4 ± 16.8 years. The mean age of a female patients who were on controlled ventilation was 63.2 ± 16.7, higher than that of male patients, which was 57.8 ± 16.6 years. The most frequent patients were over 60 years of age (52.8%). The shortest hospitalization of patients on controlled mechanical ventilation was 1 day and the longest was 120 days. Average duration of mechanical ventilation was 6.9 ± 10.5 days.

CONCLUSION

VAP is a relatively common complication in patients with MV that can increase morbidity and mortality, as well as treatment costs. It is more frequent in females and in the elderly. Medical staff should provide normal maintenance of respiratory functions to a patient who is on MV, which will reduce the risk of VAP.

Incidence, Risk Factors, and Effects on Outcome of Ventilator-Associated Pneumonia in Patients With Traumatic Brain Injury: Analysis of a Large, Multicenter, Prospective, Observational Longitudinal Study

BACKGROUND

No large prospective data, to our knowledge, are available on ventilator-associated pneumonia (VAP) in patients with traumatic brain injury (TBI).

RESEARCH QUESTION

To evaluate the incidence, timing, and risk factors of VAP after TBI and its effect on patient outcome.

STUDY DESIGN AND METHODS

This analysis is of the Collaborative European NeuroTrauma Effectiveness Research in Traumatic Brain Injury data set, from a large, multicenter, prospective, observational study including patients with TBI admitted to European ICUs, receiving mechanical ventilation for ≥ 48 hours and with an ICU length of stay (LOS) ≥ 72 hours. Characteristics of patients with VAP vs characteristics of patients without VAP were compared, and outcome was assessed at 6 months after injury by using the Glasgow Outcome Scale Extended.

RESULTS

The study included 962 patients: 196 (20.4%) developed a VAP at a median interval of 5 days (interquartile range [IQR], 3-7 days) after intubation. Patients who developed VAP were younger (median age, 39.5 [IQR, 25-55] years vs 51 [IQR, 30-66] years; P < .001), with a higher incidence of alcohol abuse (36.6% vs 27.6%; P = .026) and drug abuse (10.1% vs 4.2%; P = .009), more frequent thoracic trauma (53% vs 43%; P = .014), and more episodes of respiratory failure during ICU stay (69.9% vs 28.1%; P < .001). Age (hazard ratio [HR], 0.99; 95% CI, 0.98-0.99; P = .001), chest trauma (HR, 1.4; 95% CI, 1.03-1.90; P = .033), histamine-receptor antagonist intake (HR, 2.16; 95% CI, 1.37-3.39; P = .001), and antibiotic prophylaxis (HR, 0.69; 95% CI, 0.50-0.96; P = .026) were associated with the risk of VAP. Patients with VAP had a longer duration of mechanical ventilation (median, 15 [IQR, 10-22] days vs 8 [IQR, 5-14] days; P < .001) and ICU LOS (median, 20 [IQR, 14-29] days vs 13 [IQR, 8-21] days; P < .001). However, VAP was not associated with increased mortality or worse neurological outcome. Overall mortality at 6 months was 22%.

INTERPRETATION

VAP occurs less often than previously described in patients after TBI and has a detrimental effect on ICU LOS but not on mortality and neurological outcome.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov; No.: NCT02210221; URL: www.clinicaltrials.gov.

Evidence supporting recommendations from international guidelines on treatment, diagnosis, and prevention of HAP and VAP in adults

Clinical practice guidelines (CPGs) are intended to support clinical decisions and should be based on high-quality evidence. The objective of the study was to evaluate the quality of evidence supporting the recommendations issued in CPGs for therapy, diagnosis, and prevention of hospital-acquired and ventilator-associated pneumonia (HAP/VAP). CPGs released by international scientific societies after year 2000, using the Grades of Recommendation, Assessment, Development, and Evaluation (GRADE) methodology, were analyzed. Number and strength of recommendations and quality of evidence (high, moderate, low, and very low) were extracted and indexed in the aforementioned sections. High-quality evidence was based on randomized control trials (RCT) without important limitations and exceptionally on rigorous observational studies. Eighty recommendations were assessed, with 7 (8.7%), 24 (30.0%), 29 (36.3%), and 20 (25.0%) being supported by high, moderate, low, and very low-quality evidence, respectively. Highest evidence degree was reported for 26 prevention recommendations, with 7 (26.9%) supported by high-quality evidence and no recommendation based on very low-quality evidence. In contrast, among 9 recommendations for diagnosis and 45 for therapy, none was supported by high-quality evidence, in spite of being recommended as strong in 33.3% and 46.7%, respectively. Among HAP/VAP diagnosis recommendations, the majority of evidence was rated as low or very low-quality (55.6% and 22.2%, respectively) whereas among HAP/VAP therapy recommendations, 4/5 were rated as low and very low-quality (40% each). In conclusion, among HAP/VAP international guidelines, most recommendations, particularly in therapy, remain supported by observational studies, case reports, and expert opinion. Well-designed RCTs are urgently needed.

Drug Prevention and Control of Ventilator-Associated Pneumonia

Ventilator-associated pneumonia (VAP) is one of the most prevalent and serious complications of mechanical ventilation, which is considered a common nosocomial infection in critically ill patients. There are some great options for the prevention of VAP: (i) minimize ventilator exposure; (ii) intensive oral care; (iii) aspiration of subglottic secretions; (iv) maintain optimal positioning and encourage mobility; and (v) prophylactic probiotics. Furthermore, clinical management of VAP depends on appropriate antimicrobial therapy, which needs to be selected based on individual patient factors, such as previous antibacterial therapy, history of hospitalization or mechanical ventilation, and bacterial pathogens and antibiotic resistance patterns. In fact, antibiotic resistance has exponentially increased over the last decade, and the isolation of a multidrug-resistant (MDR) pathogen has been identified as an independent predictor of inadequate initial antibiotic therapy and which is significantly associated with increased mortality. Multiple attempts were used in the treatment of VAP, such as novel antibacterial agents, inhaled antibiotics and monoclonal antibodies. In this review, we summarize the current therapeutic options for the prevention and treatment of VAP, aiming to better management of VAP in clinical practice.

Assessment of the effectiveness of a ventilator associated pneumonia prevention bundle that contains endotracheal tube with subglottic drainage and cuff pressure monitorization

The effectiveness of prevention bundles on the occurrence and mortality of ventilator associated pneumonia (VAP) was evaluated in many studies. However, the effectiveness of endotracheal tube with subglottic secretion drainage (ETT-SD) and cuff pressure monitorization in VAP bundles have not been adequately assessed. In this study, we aimed to evaluate the effectiveness of VAP bundle containing ETT-SD and cuff pressure monitorization. This was a prospective, controlled study that was carried out between March 2011 and April 2012 including intubated patients. The study was conducted at the Anesthesiology Intensive Care Unit 1 and 2 (10 beds each) in a 898-bed university hospital. Occurrence of VAP and compliance with the parameters of the VAP prevention bundles were assessed daily. Patients intubated with the standard endotracheal tube were recruited as controls, mainly in the first six months of the study as ETT-SD and cuff pressure monometer had not yet been implemented. In the second term, patients intubated with ETT-SD were included as cases. Occurrence of VAP, mortality, and compliance with VAP prevention bundles were monitored. A total of 133 patients, 37 cases and 96 controls were recruited. VAP incidence declined from 40.82 to 22.16 per 1000 ventilator days among controls and cases, respectively (p<005). On average, VAP occurred 17.33±21.09 days in the case group and 10.43±7.83 days in the control group (p=0.04). However, mortality of cases and controls at the 14th and 30th days was not different. VAP prevention bundles including the utilization of ETT-SD, monitoring cuff pressure, and oral care with chlorhexidine were efficient in reducing the rate of VAP.

Microbial Etiology of Pneumonia: Epidemiology, Diagnosis and Resistance Patterns

Globally, pneumonia is a serious public health concern and a major cause of mortality and morbidity. Despite advances in antimicrobial therapies, microbiological diagnostic tests and prevention measures, pneumonia remains the main cause of death from infectious disease in the world. An important reason for the increased global mortality is the impact of pneumonia on chronic diseases, along with the increasing age of the population and the virulence factors of the causative microorganism. The increasing number of multidrug-resistant bacteria, difficult-to-treat microorganisms, and the emergence of new pathogens are a major problem for clinicians when deciding antimicrobial therapy. A key factor for managing and effectively guiding appropriate antimicrobial therapy is an understanding of the role of the different causative microorganisms in the etiology of pneumonia, since it has been shown that the adequacy of initial antimicrobial therapy is a key factor for prognosis in pneumonia. Furthermore, broad-spectrum antibiotic therapies are sometimes given until microbiological results are available and de-escalation cannot be performed quickly. This review provides an overview of microbial etiology, resistance patterns, epidemiology and microbial diagnosis of pneumonia.

Antibiotics for ventilator-associated pneumonia

BACKGROUND

Ventilator-associated pneumonia (VAP) is a significant cause of morbidity and mortality, complicating the medical course of approximately 10% of mechanically-ventilated patients, with an estimated attributable mortality of 13%. To treat VAP empirically, the American Thoracic Society currently recommends antibiotic therapy based on the patients' risk of colonisation by an organism with multidrug resistance. The selection of initial antibiotic therapy in VAP is important, as inappropriate initial antimicrobial treatment is associated with higher mortality and longer hospital stay in intensive care unit (ICU) patients.While guidelines exist for the antibiotic treatment of hospital-acquired pneumonia (HAP) from the American Thoracic Society and the British Society for Antimicrobial Chemotherapy, there are many limitations in the quality of available evidence. This systematic review aimed to summarise the results of all randomised controlled trials (RCTs) that compare empirical antibiotic regimens for VAP.

OBJECTIVES

The primary objective of this review was to assess the effect of different empirical antimicrobial therapies on the survival and clinical cure of adult patients with ventilator-associated pneumonia (VAP). Secondary objectives included reporting the incidence of adverse events, new superinfections, length of hospital stay, and length of intensive care unit (ICU) stay associated with these therapies.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, LILACS, CINAHL and Web of Science to December 2015; we searched ClinicalTrials.gov to September 2016.

SELECTION CRITERIA

Two review authors independently assessed RCTs comparing empirical antibiotic treatments of VAP in adult patients, where VAP was defined as new-onset pneumonia that developed more than 48 hours after endotracheal intubation. Physicians and researchers were not required to be blinded for inclusion in this review.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted study data. We pooled studies and analysed them in two ways. We examined monotherapy, or a single experimental antimicrobial drug, versus combination therapy, or multiple experimental antimicrobial drugs. We also examined carbapenem therapy versus non-carbapenem therapy.

MAIN RESULTS

We included 12 studies with 3571 participants. All included studies examined the empiric use of one antimicrobial regimen versus another for the treatment of adults with VAP, but the particular drug regimens examined by each study varied. There was potential for bias because some studies did not report outcomes for all participants. All but one study reported sources of funding or author affiliations with pharmaceutical companies.We found no statistical difference in all-cause mortality between monotherapy and combination therapy (N = 4; odds ratio (OR) monotherapy versus combination 0.97, 95% confidence interval (CI) 0.73 to 1.30), clinical cure (N = 2; OR monotherapy versus combination 0.88, 95% CI 0.56 to 1.36), length of stay in ICU (mean difference (MD) 0.65, 95% CI 0.07 to 1.23) or adverse events (N = 2; OR monotherapy versus combination 0.93, 95% CI 0.68 to 1.26). We downgraded the quality of evidence for all-cause mortality, adverse events, and length of ICU stay to moderate for this comparison. We determined clinical cure for this comparison to be of very low-quality evidence.For our second comparison of combination therapy with optional adjunctives only one meta-analysis could be performed due to a lack of trials comparing the same antibiotic regimens. Two studies compared tigecycline versus imipenem-cilastatin for clinical cure in the clinically evaluable population and there was a statistically significant increase in clinical cure for imipenem-cilastatin (N = 2; OR tigecycline versus imipenem-cilastatin 0.44, 95% CI 0.23 to 0.84). Of importance, this effect was due to a single study.We found no statistical difference in all-cause mortality between carbapenem and non-carbapenem therapies (N = 1; OR carbapenem versus non-carbapenem 0.59, 95% CI 0.30 to 1.19) or adverse events (N = 3; OR carbapenem versus non-carbapenem 0.78, 95% CI 0.56 to 1.09), but we found that carbapenems are associated with a statistically significant increase in the clinical cure (N = 3; OR carbapenem versus non-carbapenem 1.53, 95% CI 1.11 to 2.12 for intention-to-treat (ITT) analysis and N = 2; OR carbapenem versus non-carbapenem 2.29, 95% CI 1.19 to 4.43 for clinically evaluable patients analysis). For this comparison we downgraded the quality of evidence for mortality, and clinical cure (ITT and clinically evaluable populations) to moderate. We determined the quality of evidence for adverse events to be low.

AUTHORS' CONCLUSIONS

We did not find a difference between monotherapy and combination therapy for the treatment of people with VAP. Since studies did not identify patients with increased risk for multidrug-resistant bacteria, these data may not be generalisable to all patient groups. However, this is the largest meta-analysis comparing monotherapy to multiple antibiotic therapies for VAP and contributes further evidence to the safety of using effective monotherapy for the empiric treatment of VAP.Due to lack of studies, we could not evaluate the best antibiotic choice for VAP, but carbapenems as a class may result in better clinical cure than other tested antibiotics.

Epidemiology and Outcome of Ventilator-Associated Pneumonia in a Heterogeneous ICU Population in Qatar

Objective. The purpose of this study is to collect data on epidemiology, microbiology, and outcome of VAP in our ICUs for reevaluation of the therapeutic strategies. Methods. This retrospective study involved all adult patients, 15 years of age or older, diagnosed with VAP in multidisciplinary ICUs at Hamad General Hospital between January 2010 and December 2012. Results. A total of 106 patients were enrolled. The mean incidence of VAP was 5.0 per 1000 ventilator-days. It was predominant among younger age group (<60 years), male patients (80.2%), and trauma ICU admissions (49.0%). The most common comorbidity was hypertension (34%) and polytrauma (36.8%) was the most frequent admission diagnosis. 30-day mortality was 23.6% and it was significantly higher in ≥60 years age group, female gender, patients with diabetes mellitus, hypertension, chronic respiratory disease, ≥1 comorbidity, and poor functional status, smokers, medical and surgical ICU admissions, and patients with previous stay in medical/surgical wards, inappropriate empirical therapy, and admission diagnosis of respiratory failure. Gram-negative bacilli were the most frequent respiratory specimen isolates, Pseudomonas spp. being the most common. Majority of our Acinetobacter isolates were multidrug resistant. Conclusion. The incidence of VAP in our ICUs was low. Higher mortality rates were observed in certain subgroup of patients. Resistance to commonly used antimicrobials is likely to require reevaluation of the therapeutic strategies at our institution.

Elevated Plasma Matrix Metalloproteinase-9 and Its Correlations with Severity of Disease in Patients with Ventilator-Associated Pneumonia

Ventilator-associated pneumonia (VAP) increases patient mortality and medical expenditure, and a real-time and reliable method for the rapid diagnosis of VAP may help reduce fatal complications. Matrix metalloproteinases-9 (MMP-9) is considered significant in the pathogenesis of lung inflammation and infection. Therefore, we examined its relationship with the clinical course of VAP. This retrospective observational study recruited 30 healthy volunteers, 12 patients who used mechanical ventilation without the development of VAP (hereafter, patients without VAP), and 30 patients with a clinical diagnosis of VAP (hereafter, patients with VAP). The activity and level of plasma MMP-9 were determined through a gelatin zymography assay and ELISA. Our results report that both plasma MMP-9 activity and concentration were significantly elevated in the acute stage of patients with VAP when compared with control group and patients without VAP (p < 0.001). Subsequently, the plasma MMP-9 of patients with VAP decreased significantly after antibiotic treatment. Furthermore, plasma MMP-9 concentration was positively correlated with the clinical pulmonary infection score (r = 0.409, p = 0.007), WBCs (r = 0.620, p < 0.001), and neutrophils counts (r = 0.335, p = 0.035). In addition, plasma MMP-9 is an excellent tool for recognizing VAP when the cutoff level is set to 92.62 ng/mL (AUC = 0.863, 95% CI = 0.761 to 0.932). In conclusions, we concluded that MMP-9 levels play a role in the development of VAP and might have the potential to be applied in the development of VAP therapies.

Ventilators in ICU: A boon or burden

BACKGROUND AND AIMS

Ventilator-associated pneumonia (VAP) is a major challenge in intensive care units (ICUs). This challenge is even more discernible in a neurological setting owing to the predispositions of patients. Data on VAP in the neurology and neurosurgery ICUs (NNICUs) are scanty in developing countries. This study was conducted to find out the occurrence of VAP, its risk factors, microbiological profile, and antibiotic resistance in patients admitted to the NNICU of a tertiary care institute in India.

MATERIALS AND METHODS

Endotracheal aspirate and blood samples were collected from 100 patients admitted to the NNICU. Complete blood count, microscopic examination, culture and sensitivity testing of aspirate were done. Chest x-ray was also performed to aid in the diagnosis of VAP.

RESULTS

Incidence rate of VAP was found to be 24%. Acinetobacter baumannii was the most common pathogen (24.3%) isolated from patients with VAP, and all of these isolates were sensitive to meropenem. Duration of mechanical ventilation (P < 0.0001) and associated comorbid illness (P = 0.005) were found to be significantly associated with VAP, and the duration of mechanical ventilation was found to be the only independent risk factor (P < 0.0001).

CONCLUSIONS

This study highlights the risks and microbiological perspective of ventilator use among neurology patients so that adequate preventive strategies can be adopted on time.

Early-onset pneumonia after out-of-hospital cardiac arrest

Early-onset pneumonia (EOP) is a common complication after successful cardiopulmonary resuscitation. Currently, EOP diagnosis is difficult because usual diagnostic tools are blunted by the features of post-cardiac arrest syndrome and therapeutic hypothermia itself. When the diagnosis of EOP is suspected, empiric antimicrobial therapy should be considered following bronchopulmonary sampling. The onset of EOP increases the length of mechanical ventilation duration and intensive care unit stay, but its influence on survival and neurological outcome seems marginal. Therapeutic hypothermia has been recognized as an independent risk factor for this infectious complication. All together, these observations underline the need for future prospective clinical trials to better delineate pathogens and risk factors associated with EOP. In addition, there is a need for diagnostic approaches serving the accurate diagnosis of EOP.

Ventilator-Associated Pneumonia at a Tertiary-Care Center in a Developing Country: Incidence, Microbiology, and Susceptibility Patterns of Isolated Microorganisms

Objective:

Ventilator-associated pneumonia (VAP) complicates the course of up to 24% of intubated patients. Data from the Middle East are scarce. The objective of this study was to evaluate the incidence, microbiology, and antimicrobial susceptibility patterns of isolated microorganisms in VAP in a developing country.

Design:

Prospective observational cohort study.

Setting:

The American University of Beirut Medical Center, a tertiary-care center that serves as a major referral center for Lebanon and neighboring countries.

Patients:

All patients admitted to the intensive care and respiratory care units from March to September 2001, and who had been receiving mechanical ventilation for at least 48 hours, were included in the study. Results of samples submitted for culture were recorded and antimicrobial susceptibility testing of isolated pathogens was performed.

Results:

Seventy patients were entered into the study. The incidence of VAP was 47%. Gram-negative bacilli accounted for 83% of all isolates. The most commonly identified organism was Acinetobacter anitratus, followed by Pseudomonas aeruginosa. Fifty percent of all gram-negative bacterial isolates were classified as antibiotic resistant. Compared with patients without VAP, patients with VAP remained intubated for a longer period and stayed in the intensive care unit longer. VAP was not associated with an increased mortality rate.

Conclusion:

Compared with other studies, the results from this referral center in Lebanon indicate a higher incidence of VAP and a high prevalence of resistant organisms. These data are relevant because they direct the choice of empiric antibiotic therapy for VAP.

Microbiology of Ventilator–Associated Pneumonia Compared With That of Hospital-Acquired Pneumonia

Objective.

Nosocomial pneumonia is the leading cause of mortality attributed to nosocomial infection. Appropriate empirical therapy has been associated with improved survival, but data are limited regarding the etiologic agents of hospital-acquired pneumonia in non-ventilated patients (HAP). This evaluation assessed whether the currently recommended empirical therapy is appropriate for both ventilator-associated pneumonia (VAP) and HAP by evaluating the infecting flora.

Design.

Prospectively collected hospitalwide surveillance data was obtained by infection control professionals using standard Centers for Disease Control and Prevention definitions.

Setting.

A tertiary care academic hospital.

Patients.

All patients admitted from 2000 through 2003.

Results.

A total of 588 episodes of pneumonia were reported in 556 patients: 327 episodes of VAP in 309 patients, and 261 episodes of HAP in 247 Patients. The infecting flora in ventilated patients included gram-positive cocci (32.0% [oxacillin-susceptible Staphylococcus aureus {OSSA}, 9.25%; oxacillin-resistant Staphylococcus aureus {ORSA}, 17.75%]), gram-negative bacilli (59.0% {Pseudomonas aeruginosa, 17.50%; Stenotrophomonas maltophilia, 6.75%; Acinetobacter species, 7.75%), and miscellaneous pathogens (9.0%). The infecting flora in nonventilated patients included gram-positive cocci (42.59% [OSSA, 13.33%; ORSA, 20.37%]), gram-negative bacilli (39.63% [P. aeruginosa, 9.26%; S. maltophilia, 1.11%; Acinetobacter species, 3.33%), and miscellaneous pathogens (17.78%).

Conclusions.

Our data demonstrated that patients with HAP, compared with those with VAP, had a similar frequency of infection with ORSA but less commonly had infections due to P. aeruginosa, Acinetobacter species, and S. maltophilia. However, the overall frequency of infection with these pathogens was sufficiently high to warrant the use of empirical therapy likely to be active against them. Our data supports using the currently recommended empirical therapy for both HAP and VAP.

Trends in ventilator-associated pneumonia: impact of a ventilator care bundle in an Italian tertiary care hospital intensive care unit

BACKGROUND

The impact on ventilator-associated pneumonia (VAP) occurrence of a multifaceted program, including progressive strategies for VAP prevention, implemented in an Italian intensive care unit (ICU) is reported.

METHODS

All adults admitted to the ICU in 2004-2010 with a length of stay ≥72 hours and mechanical ventilation time ≥48 hours were included in the study. Demographics, clinical information, and data on VAP were extracted from the ICU-acquired infection surveillance dataset. A standardized bundle for VAP prevention was implemented in 2004. In 2008, selective digestive tract decontamination (SDD) was added to the protocol. Changes in VAP incidence were evaluated.

RESULTS

There were 1,372 subjects included in the study. Overall, 156 (11.4%) developed VAP. In the second part of the study VAP incidence decreased from 15.9% to 6.7% (P < .001). Reductions both in early-onset VAP (6.6% to 1.9%; P < .001) and late-onset VAP (9.3% to 4.7%; P = .001) incidence were observed. Multivariate analysis showed a significant reduction in the risk of developing VAP from multidrug-resistant pathogens in the bundle plus SDD period as well (odds ratio, .54; 95% confidence interval, .31-.91).

CONCLUSION

The implementation of a standardized approach to patient care, including a number of key reduction interventions, was associated with a significant reduction in the risk of developing VAP.

Impact of closed versus open tracheal suctioning systems for mechanically ventilated adults: a systematic review and meta-analysis

PURPOSE

Whether closed tracheal suctioning systems (CTSS) reduce the incidence of ventilator-associated pneumonia (VAP) compared with open tracheal suctioning systems (OTSS) is inconclusive. We conducted a systematic review and meta-analysis of randomized controlled trials that compared CTSS and OTSS.

METHODS

PubMed, the Cochrane Central Register of Controlled Trials, the Web of Science, Google Scholar, and a clinical trial registry from inception to October 2014 were searched without language restrictions. Randomized controlled trials of CTSS and OTSS that compared VAP in mechanically ventilated adult patients were included. The primary outcome was the incidence of VAP. Secondary outcomes were mortality and length of mechanical ventilation. Data were pooled using the random effects model.

RESULTS

Sixteen trials with 1,929 participants were included. Compared with OTSS, CTSS was associated with a reduced incidence of VAP (RR 0.69; 95 % CI 0.54-0.87; Q = 26.14; I (2) = 46.4 %). Compared with OTSS, CTSS was not associated with reduction of mortality (RR 0.96; 95 % CI 0.83-1.12; Q = 2.27; I (2) = 0.0 %) or reduced length of mechanical ventilation (WMD -0.45 days; 95 % CI -1.25 to 0.36; Q = 6.37; I (2) = 5.8 %). Trial sequential analysis suggested a lack of firm evidence for 20 % RR reduction in the incidence of VAP. The limitations of this review included underreporting and low quality of the included trials, as well as variations in study procedures and characteristics.

CONCLUSIONS

Based on current, albeit limited evidence, it is unlikely that CTSS is inferior to OTSS regarding VAP prevention; however, further trials at low risk of bias are needed to confirm or refute this finding.

[Cuff pressure control at the intersinve care unit: influence of nursing professionals' training]

OBJETIVE

To analyze proper control of endotracheal cuff pressure in an intensive care unit. The specific objective is to verify whether training of nursing professionals improves monitoring endotracheal cuff pressure.

BASIC PROCEDURES

the study type is descriptive, observational and retrospective. All patients were admitted to the Critical Unit II of the Clínico San Carlos Hospital between May 2010-November 2011, requiring either a tracheal tube or tracheal cannula. Studied variables were: number of in range measures, number of intubated patients, or with tracheal cannula and register. Four cuts were made on all admitted patients admitted during the study period in order to measure endotracheal cuff pressure. Two cuts were performed before the professional nurses training and the other two cuts after a specific training with respect to endotracheal cuff pressure and Zero pneumonia.

RESULTS

There were 74 measurements. The first cut obtained 40.74% of measures in range. In the second cut 61.90% of measures were identified in range. In the third cut, it was found that 85.7% of measures were in range and in the fourth court, it was noted the 89.47% of measures were in range.

CONCLUSIONS

Monitoring of the endotracheal cuff pressure was inadequate before specific training of professionals. Nursing professionals training facilitates the correct measurement of the endotracheal cuff pressure, which improves patient safety.

Association of compliance of ventilator bundle with incidence of ventilator-associated pneumonia and ventilator utilization among critical patients over 4 years

BACKGROUND:

Several studies showed that the implementation of the Institute for Healthcare Improvement (IHI) ventilator bundle alone or with other preventive measures are associated with reducing Ventilator-Associated Pneumonia (VAP) rates. However, the association with ventilator utilization was rarely examined and the findings were conflicting. The objectives were to validate the bundle association with VAP rate in a traditionally high VAP environment and to examine its association with ventilator utilization.

MATERIALS AND METHODS:

The study was conducted at the adult medical-surgical intensive care unit (ICU) at King Abdulaziz Medical City, Saudi Arabia, between 2010 and 2013. VAP data were collected by a prospective targeted surveillance as per Centers for Disease Control and Prevention (CDC)/National Healthcare Safety Network (NHSN) methodology while bundle data were collected by a cross-sectional design as per IHI methodology.

RESULTS:

Ventilator bundle compliance significantly increased from 90% in 2010 to 97% in 2013 (P for trend < 0.001). On the other hand, VAP rate decreased from 3.6 (per 1000 ventilator days) in 2010 to 1.0 in 2013 (P for trend = 0.054) and ventilator utilization ratio decreased from 0.73 in 2010 to 0.59 in 2013 (P for trend < 0.001). There were negative significant correlations between the trends of ventilator bundle compliance and VAP rate (cross-correlation coefficients −0.63 to 0.07) and ventilator utilization (cross-correlation coefficients −0.18 to −0.63).

CONCLUSION:

More than 70% improvement of VAP rates and approximately 20% improvement of ventilator utilization were observed during IHI ventilator bundle implementation among adult critical patients in a tertiary care center in Saudi Arabia. Replicating the current finding in multicenter randomized trials is required before establishing any causal link.

Strategies to prevent ventilation-associated pneumonia: the effect of cuff pressure monitoring techniques and tracheal tube type on aspiration of subglottic secretions: an in-vitro study

BACKGROUND

Ventilation-associated pneumonia (VAP) is the commonest nosocomial infection in intensive care. Implementation of a VAP prevention care bundle is a proven method to reduce its incidence. The UK care bundle recommends maintenance of the tracheal tube cuff pressure at 20 to 30  cmH₂O with 4-hourly pressure checks and use of tracheal tubes with subglottic aspiration ports in patients admitted for more than 72  h.

OBJECTIVE

To evaluate the effects of tracheal tube type and cuff pressure monitoring technique on leakage of subglottic secretions past the tracheal tube cuff.

DESIGN

Bench-top study.

SETTING

Laboratory.

INTERVENTIONS

A model adult trachea with simulated subglottic secretions was intubated with a tracheal tube with the cuff inflated to 25  cmH₂O. Experiments were conducted using a Portex Profile Soft Seal tracheal tube with three cuff pressure monitoring strategies and using a Portex SACETT tracheal tube with intermittent cuff pressure checks.

OUTCOME MEASURES

Rate of simulated secretion leakage past the tracheal tube cuff.

RESULTS

Mean ± SD leakage of fluid past the Profile Soft Seal tracheal tube cuff was 2.25 ± 1.49  ml  min⁻¹ with no monitoring of cuff pressure, 2.98 ± 1.63  ml  min⁻¹ with intermittent cuff pressure monitoring and 3.83 ± 2.17  ml  min⁻¹ with continuous cuff pressure monitoring (P <0.001). Using a SACETT tracheal tube with a subglottic aspiration port and aspirating the simulated secretions prior to intermittent cuff pressure checks reduced the leakage rate to 0.50 ± 0.48  ml  min⁻¹ (P <0.001).

CONCLUSION

Subglottic secretions leaked past the tracheal tube cuff with all tube types and cuff pressure monitoring strategies in this model. Significantly higher rates were observed with continuous cuff pressure monitoring and significantly lower rates were observed when using a tracheal tube with a subglottic aspiration port. Further evaluation of medical device performance is needed in order to design more effective VAP prevention strategies.

Ventilator-associated pneumonia in patients admitted to intensive care units, using open or closed endotracheal suctioning

Background:

Critically ill patients under mechanical ventilation require frequent suctioning of airway secretion. Closed suction permits suctioning without disconnection from ventilator; so it might decrease hypoxemia and infection rate.

Objectives:

This study aimed to evaluate the effect of closed tracheal suction system (CTSS) versus open tracheal suction system (OTSS).

Patients and Methods:

This is a prospective randomized study, which was carried on 100 patients in surgical Intensive Care Unit requiring mechanical ventilation for more than 48 hours from June 2012 to November 2013. In two groups, suction was performed based on the patients' need as well as physician's or nurses' decision on tracheal secretions. Patients randomly allocated into two groups (50 patients each): CTSS group and OTSS group. Patients were monitored for developing ventilator-associated pneumonia (VAP) during the study. Throat samples were taken on admission and two times per week from each patient. Tracheal samples were performed during endotracheal intubation, two times per week during mechanical ventilation and during extubation.

Results:

Drainage of subglottic secretions decreased the incidence of VAP (P < 0.05). Also type of the pharmacologic medicine for stress ulcer prophylaxis has significant effect on VAP incidence. Among the patients in OTSS and CTSS groups, 20% and 12% developed VAP, respectively. Use of CTSS compared with OTSS did not show statistically significant effect on VAP incidence in multivariate analysis; however, OR (odds ratio) tended to identify OTSS as an exposure factor for the development of VAP (OR = 1.92; CI = 0.45-8.30; = 0.38) compared with the CTSS. Higher levels of APACHE II score, sinusitis and tracheostomy put the patients at the risk of VAP. However, using heat and moisture exchanger (HME) instead of humidifier decreased this risk.

Conclusions:

Based on the results obtained from our study, impact of suctioning is similar between CTSS and OTSS regarding the occurrence of VAP. It seems that physicians must consider many factors such as duration of mechanical ventilation, comorbidities, oxygenation parameters, number of required suctioning, and the cost prior to using each type of tracheal suction system.

Education alone is not enough in ventilator associated pneumonia care bundle compliance

Objective:

Ventilator-associated pneumonia (VAP) described as a secondary and preventable consequence in mechanically ventilated patients, emerges 48 h or more after patients intubation. Considering the high morbidity and mortality rate of VAP and the fact that VAP is preventable, it seemed necessary to evaluate care bundle compliance rate and effect of education on its improvement.

Methods:

This observational study was conducted on 10 Intensive Care Units (ICUs) of four university affiliated hospitals in three steps. In the first step, VAP care bundle compliance including head of bed (HOB) elevation, endotracheal cuff pressure (ETCP), mouthwash time, utilizing close suction systems, subglottic secretion drainage, type of suction package, and hand wash before suctioning was evaluated. In the second and third steps, ICU staffs were trained and its effect on VAP care bundle compliance was investigated. Finally, an inquiry from nurses was conducted to evaluate the obtained results.

Findings:

A total of 552 checklists consisting of 294 observations in the pre-education group and 258 observations in the posteducation group were filled. Mean VAP care bundle compliance in pre-education and posteducation stages was 36.5% and 41.2%, respectively (P > 0.05). Except for patients' mouth washing, there were no improvement in HOB elevation (>30°), hand washing and ETCP after education. Based on the results of questionnaire received from nurses at the end of study, more than 90% of nurses believed that lack of rigid monitoring of VAP care bundle is a main reason of low adherence for VAP care bundle compliance.

Conclusion:

The adherence to VAP care bundle was inappropriate. Education seems to be ineffective on improving VAP care bundle compliance. Frequent recall of the necessity of the VAP care bundle and the continuous supervision of ICU staffs is highly recommended.

Risk factors for ventilator-associated pneumonia in neonatal intensive care unit patients

Ventilator-associated pneumonia (VAP) is a serious complication in neonatal patients on mechanical ventilation. The objective of this study was to examine the incidence and risk factors associated with VAP, particularly in every 7-day versus every 14-day ventilator circuit changes, in a neonatal intensive care unit (NICU). Seventy-one neonates hospitalized in the NICU were enrolled. First, the neonates were divided into groups with and without VAP. On univariate logistic regression analyses, prolonged mechanical ventilation, frequent re-intubation, low gestational age, and low birth weight (BW) were significant risk factors for VAP development. After adjustments for other variables, only BW <626 g was a significant independent predictor for VAP in NICU infants. Second, to examine the effect of the frequency of changing ventilator circuits on the incidence of VAP, circuit changes were compared between the every 7-day group and the every 14-day group. The incidence of VAP per 1000 ventilator days was 9.66 for the every 7-day group and 8.08 for the every 14-day group, and there was no significant difference between the 2 groups. BW <626 g was a significant independent predictor of VAP, and decreasing the frequency of ventilator circuit changes from every 7 days to 14 days had no adverse effect on the VAP rate in the NICU.

Continuous endotracheal tube cuff pressure control system protects against ventilator-associated pneumonia

INTRODUCTION

The use of a system for continuous control of endotracheal tube cuff pressure reduced the incidence of ventilator-associated pneumonia (VAP) in one randomized controlled trial (RCT) with 112 patients but not in another RCT with 142 patients. In several guidelines on the prevention of VAP, the use of a system for continuous or intermittent control of endotracheal cuff pressure is not reviewed. The objective of this study was to compare the incidence of VAP in a large sample of patients (n = 284) treated with either continuous or intermittent control of endotracheal tube cuff pressure.

METHODS

We performed a prospective observational study of patients undergoing mechanical ventilation during more than 48 hours in an intensive care unit (ICU) using either continuous or intermittent endotracheal tube cuff pressure control. Multivariate logistic regression analysis (MLRA) and Cox proportional hazard regression analysis were used to predict VAP. The magnitude of the effect was expressed as odds ratio (OR) or hazard ratio (HR), respectively, and 95% confidence interval (CI).

RESULTS

We found a lower incidence of VAP with the continuous (n = 150) than with the intermittent (n = 134) pressure control system (22.0% versus 11.2%; p = 0.02). MLRA showed that the continuous pressure control system (OR = 0.45; 95% CI = 0.22-0.89; p = 0.02) and the use of an endotracheal tube incorporating a lumen for subglottic secretion drainage (SSD) (OR = 0.39; 95% CI = 0.19-0.84; p = 0.02) were protective factors against VAP. Cox regression analysis showed that the continuous pressure control system (HR = 0.45; 95% CI = 0.24-0.84; p = 0.01) and the use of an endotracheal tube incorporating a lumen for SSD (HR = 0.29; 95% CI = 0.15-0.56; p < 0.001) were protective factors against VAP. However, the interaction between type of endotracheal cuff pressure control system (continuous or intermittent) and endotracheal tube (with or without SSD) was not statistically significant in MLRA (OR = 0.41; 95% CI = 0.07-2.37; p = 0.32) or in Cox analysis (HR = 0.35; 95% CI = 0.06-1.84; p = 0.21).

CONCLUSIONS

The use of a continuous endotracheal cuff pressure control system and/or an endotracheal tube with a lumen for SSD could help to prevent VAP in patients requiring more than 48 hours of mechanical ventilation.

Guidelines for the prevention of ventilator-associated pneumonia and their implementation. The Spanish "Zero-VAP" bundle

BACKGROUND

"Zero-VAP" is a proposal for the implementation of a simultaneous multimodal intervention in Spanish intensive care units (ICU) consisting of a bundle of ventilator-associated pneumonia (VAP) prevention measures.

METHODS/DESIGN

An initiative of the Spanish Societies of Intensive Care Medicine and of Intensive Care Nurses, the project is supported by the Spanish Ministry of Health, and participation is voluntary. In addition to guidelines for VAP prevention, the "Zero-VAP" Project incorporates an integral patient safety program and continuous online validation of the application of the bundle. For the latter, VAP episodes and participation indices are entered into the web-based Spanish ICU Infection Surveillance Program "ENVIN-HELICS" database, which provides continuous information about local, regional and national VAP incidence rates. Implementation of the guidelines aims at the reduction of VAP to less than 9 episodes per 1000 days of mechanical ventilation. A total of 35 preventive measures were initially selected. A task force of experts used the Grading of Recommendations, Assessment, Development and Evaluation Working Group methodology to generate a list of 7 basic "mandatory" recommendations (education and training in airway management, strict hand hygiene for airway management, cuff pressure control, oral hygiene with chlorhexidine, semi-recumbent positioning, promoting measures that safely avoid or reduce time on ventilator, and discouraging scheduled changes of ventilator circuits, humidifiers and endotracheal tubes) and 3 additional "highly recommended" measures (selective decontamination of the digestive tract, aspiration of subglottic secretions, and a short course of iv antibiotic).

DISCUSSION

We present the Spanish VAP prevention guidelines and describe the methodology used for the selection and implementation of the recommendations and the organizational structure of the project. Compared to conventional guideline documents, the associated safety assurance program, the online data recording and compliance control systems, as well as the existence of a pre-defined objective are the distinct features of "Zero VAP".

Aetiological agents of ventilator-associated pneumonia and its resistance pattern - a threat for treatment

BACKGROUND

Ventilator-associated pneumonia (VAP) is a common type of nosocomial pneumonia encountered in intensive care units. There are several aetiological agents which make treatment challenging. Improper antibiotic treatment of ventilated patients may lead to the emergence of multidrug resistant (MDR) pathogens.

METHOD

A prospective study was performed over a period of 20 months. Our study had two arms: the first, 'Incidence and risk factors of VAP in a tertiary care hospital' was the subject of an earlier publication; we therefore present the second investigative arm in this work. The aetiological agents of patients on mechanical ventilation (MV) were identified by standard bacteriological method. The susceptibility pattern was evaluated by Kirby-Bauer disc diffusion method. Extended spectrum beta lactamase (ESBL) testing was performed by combination disc method, and metallo-beta lactamase (MBL) testing was performed by EDTA disk synergy test (EDS).

RESULTS

Late-onset VAP was associated with Pseudomonas aeruginosa, Klebsiella pneumoniae and Escherichia coli, while early-onset VAP was commonly caused by members of Enterobacteriaceae, Candida albicans and Staphylococcus aureus. 72.2 per cent of VAP patients had monomicrobial and 27.8 per cent had polymicrobial infection. Out of the 24 isolates obtained from patients with VAP, seven (29.2 per cent) were MDR pathogens. ESBL and MBL production was detected in 40 per cent and 20 per cent of Klebsiella pneumoniae isolated in our study. Around 50 per cent of isolates associated with late-onset VAP were MDR, while 22.2 per cent isolates obtained from patients with earlyonset VAP were MDR.

CONCLUSION

VAP is a nosocomial pneumonia that is common among ventilated patients. The aetiological agents vary from common organisms to MDR pathogens that are difficult to treat. A proper knowledge of MDR pathogens and early isolation followed by prevention of prolonged antibiotic therapy can reduce the mortality of late onset VAP.

Efficacy of single-dose antibiotic against early-onset pneumonia in comatose patients who are ventilated

BACKGROUND

Comatose patients present a high risk of early-onset ventilator-associated pneumonia (EO-VAP) for which antibiotic prophylaxis has been proposed. Comatose patients were studied to evaluate the efficacy of a single-dose of antibiotic prophylaxis at intubation against EO-VAP.

METHODS

A prospective cohort of comatose patients (Glasgow Coma Score ≤ 8) who were admitted in 2009-2010 and administered a single-dose of antibiotic within 4 h of intubation was compared with comatose patients (admitted ≥ 4 h after intubation in 2009-2010 or admitted in 2007-2008) who did not receive antibiotic prophylaxis. We analyzed the incidence of EO-VAP, late-onset VAP, and ventilator-associated tracheobronchitis in both groups. Propensity scores for receiving antibiotic prophylaxis were derived on the basis of patients' characteristics (eg, age and severity) to assess its impact on EO-VAP development.

RESULTS

We included 129 patients (71 in the prophylaxis group and 58 in the control group). The global incidence of VAP and incidence of EO-VAP were lower in the prophylaxis group: 10.8 vs 28.4 episodes/1,000 days on mechanical ventilation (P = .015) and 4.4 vs 23.1 episodes/1,000 days on mechanical ventilation (P = .02), respectively. The incidence of late-onset VAP did not differ. The prophylaxis group tended toward lower incidence of ventilator-associated tracheobronchitis (15.5% vs 25.9%, P = .14). No differences in mortality were found between groups. The propensity-score regression analysis confirmed that a single dose of antibiotic prophylaxis was independently associated with lower incidence of EO-VAP (OR, 0.11; 95% CI, 0.02-0.58; P = .009).

CONCLUSIONS

A single dose of antibiotic prophylaxis at intubation might lower the incidence of EO-VAP. However, a randomized clinical trial should be conducted to confirm our findings.

Selective decontamination of the digestive tract and selective oropharyngeal decontamination in intensive care unit patients: a cost-effectiveness analysis

OBJECTIVE

To determine costs and effects of selective digestive tract decontamination (SDD) and selective oropharyngeal decontamination (SOD) as compared with standard care (ie, no SDD/SOD (SC)) from a healthcare perspective in Dutch Intensive Care Units (ICUs).

DESIGN

A post hoc analysis of a previously performed cluster-randomised trial (NEJM 2009;360:20).

SETTING

13 Dutch ICUs.

PARTICIPANTS

Patients with ICU-stay of >48 h that received SDD (n=2045), SOD (n=1904) or SC (n=1990).

INTERVENTIONS

SDD or SOD.

PRIMARY AND SECONDARY OUTCOME MEASURES

Effects were based on hospital survival, expressed as crude Life Years Gained (cLYG). The incremental cost-effectiveness ratio (ICER) was calculated, with corresponding cost acceptability curves. Sensitivity analyses were performed for discount rates, costs of SDD, SOD and mechanical ventilation.

RESULTS

Total costs per patient were €41 941 for SC (95% CI €40 184 to €43 698), €40 433 for SOD (95% CI €38 838 to €42 029) and €41 183 for SOD (95% CI €39 408 to €42 958). SOD and SDD resulted in crude LYG of +0.04 and +0.25, respectively, as compared with SC, implying that both SDD and SOD are dominant (ie, cheaper and more beneficial) over SC. In cost-effectiveness acceptability curves probabilities for cost-effectiveness, compared with standard care, ranged from 89% to 93% for SOD and from 63% to 72% for SDD, for acceptable costs for 1 LYG ranging from €0 to €20 000. Sensitivity analysis for mechanical ventilation and discount rates did not change interpretation. Yet, if costs of the topical component of SDD and SOD would increase 40-fold to €400/day and €40/day (maximum values based on free market prices in 2012), the estimated ICER as compared with SC for SDD would be €21 590 per LYG. SOD would remain cost-saving.

CONCLUSIONS

SDD and SOD were both effective and cost-saving in Dutch ICUs.

Epidemiology and outcomes of ventilator-associated pneumonia in northern Brazil: an analytical descriptive prospective cohort study

BACKGROUND

Ventilator-associated pneumonia (VAP) is considered the most common nosocomial infection in the intensive care unit (ICU), but its features are not fully known in many hospitals in Brazil. We identified clinical and epidemiological aspects associated with VAP in an intensive care unit (ICU) in a general public hospital in northern Brazil and performed an analytical descriptive prospective cohort study.

METHODS

We analyzed data from thirty-three patients who developed VAP while in the ICU. Clinical and epidemiological data of patients were obtained and tracheal secretions were submitted to culture. Microbial isolates were identified and evaluated for resistance against antimicrobial agents by using the automated Vitek 2 system.

RESULTS

The frequency of VAP was 26.2% in patients submitted to invasive mechanical ventilation for at least 48 hours, and death occurred in 78.8% of cases. Only the presence of comorbidity showed a significant association (P = 0.029) with death. The most commonly found bacteria were Pseudomonas aeruginosa, Acinetobacter spp., and Enterobacteriaceae. We also found a frequency of 54.5% of multiresistant bacteria associated with VAP, and previous antibiotic therapy was used in 97% of patients.

CONCLUSIONS

VAP in our ICU presented with a high frequency and was mainly caused by multiresistant bacteria. Implementation of rational protocols for the use of antibacterial agents and rapid delivery of culture and susceptibility test results are essential. This may help decrease VAP-related mortality rates by multiresistant bacteria in the ICU.

[Hygiene in intensive care units in Frankfurt am Main, Germany]

: The German Commission on Hospital Hygiene and Infection Prevention has published several recommendations regarding hygiene in the intensive care unit. Compliance with these recommendations was surveyed.

METHODS

In 2005 and 2011, the intensive care units of all hospitals in Frankfurt am Main, Germany, were examined by members of the public health department, using a checklist based on the respective recommendations.

RESULTS

Recommendations on the architecture and function of intensive care wards were almost fully complied with, except for the stipulated amount of space and nursing personnel. Compliance with recommendations for prevention of ventilator-associated pneumonia and for prevention of catheter-related bloodstream infections was excellent, with only some minor exceptions. Regarding hand hygiene, in 2011 fewer faults were documented than in 2005. All hospitals took part in the German project of the world-wide campaign "clean care is safer care." In 2005, device-associated infections were surveyed in 92% intensive care units, and in 2011 in all of them. By 2011, screening of methicillin-resistant Staphylococcus aureus had been established in all intensive care units.

CONCLUSION

Most problems that were observed regarded a scarcity of space and of facilities for isolation of patients and of nursing personnel. Improvements were seen in hand hygiene and in screening for multidrug resistant organisms (MDRO).

Assessment of a training programme for the prevention of ventilator-associated pneumonia

BACKGROUND

Ventilator-associated pneumonia (VAP) is the most frequent nosocomial infection in intensive care units (ICUs). Most published studies have analysed nurses' theoretical knowledge about a specific procedure; however, the transfer of this knowledge to the practice has received little attention.

AIM

To assess the impact of training session on nurses' knowledge regarding VAP, compliance with VAP preventive measures, VAP incidence and determining whether nursing workload affects compliance.

METHOD

A prospective, quasiexperimental, pre- and post-study of the nursing team in a 16-bed medical/surgical ICU. Pre-intervention phase: a questionnaire to assess nurses' knowledge of VAP prevention measures, direct observation and review of clinical records to assess compliance. Intervention phase: eight training sessions for nurses. The post-intervention phase mirrored the pre-intervention phase.

FINDINGS

Nurses answered more questions correctly on the post-intervention questionnaire than on the pre-intervention (17·87 ± 2·69 versus 15·91 ± 2·68, p = 0·002). Compliance with the following measures was better during the post-intervention period (p = 0·001): use of the smallest possible nasogastric tube, controlled aspiration of subglottic secretions and endotracheal tube cuff pressure, use of oral chlorhexidine and recording the endotracheal tube fixation number. VAP incidence remained unchanged throughout the study. However, a trend towards lower incidence of late (>4 days after intubation) VAP was observed (4·6 versus 3·1 episodes/1000 ventilation days, p = 0·37).

CONCLUSION

The programme improved both knowledge of and compliance with VAP preventive measures, although improved knowledge did not always result in improved compliance.

Alveolar fibrocyte percentage is an independent predictor of poor outcome in patients with acute lung injury

OBJECTIVE

Fibrocytes are mesenchymal progenitors involved in normal and pathologic repair. The aims of this study were: 1) to quantify fibrocytes in bronchoalveolar lavage fluid from patients with or without acute lung injury and acute respiratory distress syndrome; and 2) to evaluate the prognostic value of bronchoalveolar lavage fibrocyte percentage in patients with acute lung injury and acute respiratory distress syndrome.

DESIGN

Prospective cohort study.

SETTING

Three intensive care units of a large tertiary referral center.

PATIENTS

One hundred twenty-two ventilated patients requiring bronchoalveolar lavage were enrolled (62 acute respiratory distress syndrome, 30 acute lung injury, 30-ventilated patients without acute lung injury and acute respiratory distress syndrome).

INTERVENTIONS

After bronchoalveolar lavage collection during standard care, the patients were followed up for 28 days and clinical outcome was recorded. Fibrocytes (CD45+/collagen 1+) were quantified in bronchoalveolar lavage by flow cytometry. Comparison of bronchoalveolar lavage fibrocyte percentage from patients with or without acute lung injury and acute respiratory distress syndrome was performed using a Wilcoxon test. A multivariate analysis using a Cox model was performed to study the independent predictors of survival.

MEASUREMENTS AND MAIN RESULTS

Fibrocytes were detected in 90 of 92 (98%) bronchoalveolar lavages from patients with acute lung injury and acute respiratory distress syndrome. The median percentage of bronchoalveolar lavage fibrocytes was significantly higher in patients with acute lung injury and acute respiratory distress syndrome (5.0%) in comparison with ventilated control subjects (0.9%, p < .0001). After adjustment for age, comorbidity of malignancy, and severity of illness, a bronchoalveolar lavage fibrocyte percentage >6% was independently associated with a higher 28-day mortality in patients with acute lung injury and acute respiratory distress syndrome (hazard ratio [95% confidence interval] 6.15 [2.78-13.64], p ≤ .0001). Addition of bronchoalveolar lavage fibrocyte percentage in a clinical model predicting mortality in patients with acute lung injury and acute respiratory distress syndrome improved global fit and discriminatory capacity (c-statistic, 0.78-0.85; p = .007).

CONCLUSIONS

Fibrocytes are detectable in bronchoalveolar lavage during acute lung injury and acute respiratory distress syndrome. A bronchoalveolar lavage fibrocyte percentage >6% provides an additive prognostic value to clinical predictors and may be useful to identify patients with acute lung injury and acute respiratory distress syndrome at highest risk of an adverse outcome.

Strategies in the prevention of ventilator-associated pneumonia

Ventilator-associated pneumonia (VAP) remains a significant problem in the hospital setting, with very high morbidity, mortality, and cost. We performed an evidence-based review of the literature focusing on clinically relevant pharmacological and nonpharmacological interventions to prevent VAP. Owing to the importance of this condition the implementation of preventive measures is paramount in the care of mechanically ventilated patients. There is evidence that these measures decrease the incidence of VAP and improve outcomes in the intensive care unit. A multidisciplinary approach, continued education, and ventilator protocols ensure the implementation of these measures. Future research will continue to investigate cost/benefit relationships, antibiotic resistance, as well as newer technologies to prevent contamination and aspiration in mechanically ventilated patients.

Pneumonie

Die maximale Inzidenz von ventilatorassoziierter Pneumonie (VAP) liegt nach Ibrahim et al. (2001) zwischen dem 6. und dem 10. Tag (◘ Abb. 13.1).

An open-labelled randomized controlled trial comparing costs and clinical outcomes of open endotracheal suctioning with closed endotracheal suctioning in mechanically ventilated medical intensive care patients

PURPOSE

Closed endotracheal suctioning (CES) may impact ventilator-associated pneumonia (VAP) risk by reducing environmental contamination. In developing countries where resource limitations constrain the provision of optimal bed space for critically ill patients, CES assumes greater importance.

MATERIALS AND METHODS

In this prospective, open-labeled, randomized controlled trial spanning 10 months, we compared CES with open endotracheal suctioning (OES) in mechanically ventilated patients admitted to the medical intensive care unit (ICU) of a university-affiliated teaching hospital. Patients were followed up from ICU admission to death or discharge from hospital. Primary outcome was incidence of VAP. Secondary outcomes included mortality, cost, and length of stay.

RESULTS

Two hundred patients were recruited, 100 in each arm. The incidence of VAP was 23.5%. Closed endotracheal suctioning was associated with a trend to a reduced incidence of VAP (odds ratio, 1.86; 95% confidence interval, 0.91-3.83; P = .067). A significant benefit was, however, observed with CES for late-onset VAP (P = .03). Mortality and duration of ICU and hospital stay were similar in the 2 groups. The cost of suction catheters and gloves was significantly higher with CES (Rs 272 [US $5.81] vs Rs 138 [US $2.94], P < .0001). Nine patients need to be treated with CES to prevent 1 VAP (95% confidence interval, -0.7 to 22).

CONCLUSIONS

In the ICU setting in a developing country, CES may be advantageous in reducing the incidence of VAP, particularly late-onset VAP. These results mandate further studies in this setting before specific guidelines regarding the routine use of CES are proposed.

Ventilator-associated pneumonia: a review

Ventilator-associated pneumonia (VAP) is the most frequent intensive-care-unit (ICU)-acquired infection, with an incidence ranging from 6 to 52% [1,2,3,4]. Several studies have shown that critically ill patients are at high risk for getting such nosocomial infections [3,4]. VAP continues to be a major cause of morbidity, mortality and increased financial burden in ICUs [5,6,7,8]. Over the years there has been a significant advance in our understanding of ventilator associated pneumonia. This article reviews the various aspects of VAP such as definition, risk factors, etiological agents, diagnosis, treatment and prevention with emphasis on the recent advances.

New issues and controversies in the prevention of ventilator-associated pneumonia

In the past 2 years, American, Canadian, and European scientific societies have published their new evidence-based guidelines for ventilator-associated pneumonia (VAP) prevention. However, these guidelines did not review some potentially useful strategies, such as the use of an endotracheal tube with an ultrathin cuff membrane, an endotracheal tube with a low-volume/low-pressure cuff, a device for continuous monitoring of the endotracheal tube cuff pressure, a device to remove biofilm from the inner site of the endotracheal tube, and saline instillation before tracheal suctioning. Only a few guidelines analyze the time of tracheostomy, and so no firm recommendations can be made regarding its importance. In addition, the guidelines diverge on the use of heat and moisture exchangers or heated humidifiers and on the use of an endotracheal tube coated with antimicrobial agents. The current review focuses on measures of VAP prevention for which there is no clear recommendation, or the use of which is controversial. A review of the literature suggests that the use of an endotracheal tube with an ultrathin and tapered-shape cuff membrane and coated in antimicrobial agents may reduce the risk of VAP. These features offer an attractive way to optimize the VAP prevention capacity of endotracheal tubes with a lumen for subglottic secretion drainage. We believe that early tracheostomy should be considered, based on the length reduction of mechanical ventilation and intensive care unit stay, reduction of mortality, and on patient comfort, although early tracheostomy has not yet been shown to favorably impact the incidence of VAP. We believed that heat and moisture exchangers should be considered based on the benefits in terms of cost savings. More research is necessary to clarify the role of continuous cuff pressure monitoring, removal of biofilm formation in the endotracheal tubes, and routine saline instillation before tracheal suctioning.

Comparison of the effect of LPS and PAM3 on ventilated lungs

BACKGROUND

While lipopolysaccharide (LPS) from Gram-negative bacteria has been shown to augment inflammation in ventilated lungs information on the effect of Gram-positive bacteria is lacking. Therefore the effect of LPS and a lipopetide from Gram-positive bacteria, PAM3, on ventilated lungs were investigated.

METHODS

C57/Bl6 mice were mechanically ventilated. Sterile saline (sham) and different concentrations of LPS (1 microg and 5 microg) and PAM3 (50 nM and 200 nM) were applied intratracheally. Lung function parameters and expression of MIP-2 and TNFalpha as well as influx of neutrophils were measured.

RESULTS

Mechanical ventilation increased resistance and decreased compliance over time. PAM3 but not LPS significantly increased resistance compared to sham challenge (P < 0.05). Both LPS and PAM3 significantly increased MIP-2 and TNFalpha mRNA expression compared to sham challenge (P < 0.05). The numbers of neutrophils were significantly increased after LPS at a concentration of 5 microg compared to sham (P < 0.05). PAM3 significantly increased the numbers of neutrophils at both concentrations compared to sham (P < 0.05).

CONCLUSIONS

These data suggest that PAM3 similar to LPS enhances ventilator-induced inflammation. Moreover, PAM3 but not LPS increases pulmonary resistance in ventilated lungs. Further studies are warranted to define the role of lipopetides in ventilator-associated lung injury.

[Debates in intensive medicine: Pro: selective decontamination]

Selective decontamination of the digestive tract (SDD) has been proven to prevent infections of endogenous development and reduce mortality in critically ill patients under prolonged mechanical ventilation. Historical arguments against its use, like the development of bacterial resistance or the selection of resistant microorganisms and the absence of influence on mortality have not been confirmed. Moreover, recent clinical trials designed to evaluate these variables, show remarkable reductions in the incidence of resistant bacteria and a significant beneficial effect on mortality. Furthermore, no increases in workload or costs have been documented. A few studies with post-trial and intermediate range follow-up periods didn't find increases in resistance. Implementation of SDD requires motivation and leadership in order to achieve cooperation of other related hospital specialists, training of several categories of healthcare professionals, and continuous monitoring of results. In order to facilitate the use of SDD in the critically ill, this preventive measure should be incorporated in guidelines of national and international scientific societies and working groups involved in the care of the critically ill patient. The general implementation of SDD in our intensive care units must be accompanied by a registry in order to be able to monitor the effect on the incidence of infection and bacterial resistance. For this purpose, the Spanish national ICU infection and resistance surveillance programme ENVIN-HELICS, active over the last 15 years, constitutes both a more than adequate tool, and the convenient reference data base.

Evaluation of a 24-hour emergency bronchoscopy service in a tertiary care hospital

BACKGROUND

Flexible bronchoscopy has become an important diagnostic and therapeutic tool for the management of patients with various diseases of the chest. Availability of a 24-hour bronchoscopy service equipped with experienced personnel is becoming increasingly important especially for intensive care patients. However, such services have been implemented only in a few medical centres. The aim of this study was to evaluate the usage of a 24-hour emergency service in a large university hospital with a 1 year prospective analysis of emergency bronchoscopy service in a tertiary care centre.

METHODS

Frequencies, indications and efficiency of therapeutic interventions were evaluated after each bronchoscopy using a specially designed questionnaire. All bronchoscopies were performed as emergency procedures out of operational schedule. A total of 614 emergency bronchoscopies were performed, 88% of them in intensive care units.

RESULTS

The vast majority (84.5%) of the procedures were necessary for therapeutic interventions; that is, atelectasis, airway secretion, aspiration or bronchopulmonary bleeding. According to prespecified criteria, 37.6% (n = 195) of therapeutic procedures were assessed as 'very helpful' and 3.9% (n = 20) as 'life saving'. Diagnostic bronchoscopies were performed mainly to collect airway material for microbiological evaluations in immunocompromised patients. In these cases, the diagnostic yield was approximately 50%.

CONCLUSION

The availability of a 24-hour bronchoscopy service has been found to improve patient care and was occasionally considered life saving. Thus, comparable services should be made more widely available.