Empiric antibiotic therapy for suspected ventilator-associated pneumonia: a systematic review and meta-analysis of randomized trials

WHO's essential medicines and AWaRe: recommendations on first- and second-choice antibiotics for empiric treatment of clinical infections

The WHO Model List of Essential Medicines (EML) prioritizes medicines that have significant global public health value. The EML can also deliver important messages on appropriate medicine use. Since 2017, in response to the growing challenge of antimicrobial resistance, antibiotics on the EML have been reviewed and categorized into three groups: Access, Watch, and Reserve, leading to a new categorization called AWaRe. These categories were developed taking into account the impact of different antibiotics and classes on antimicrobial resistance and the implications for their appropriate use. The 2023 AWaRe classification provides empirical guidance on 41 essential antibiotics for over 30 clinical infections targeting both the primary health care and hospital facility setting. A further 257 antibiotics not included on the EML have been allocated an AWaRe group for stewardship and monitoring purposes. This article describes the development of AWaRe, focussing on the clinical evidence base that guided the selection of Access, Watch, or Reserve antibiotics as first and second choices for each infection. The overarching objective was to offer a tool for optimizing the quality of global antibiotic prescribing and reduce inappropriate use by encouraging the use of Access antibiotics (or no antibiotics) where appropriate. This clinical evidence evaluation and subsequent EML recommendations are the basis for the AWaRe antibiotic book and related smartphone applications. By providing guidance on antibiotic prioritization, AWaRe aims to facilitate the revision of national lists of essential medicines, update national prescribing guidelines, and supervise antibiotic use. Adherence to AWaRe would extend the effectiveness of current antibiotics while helping countries expand access to these life-saving medicines for the benefit of current and future patients, health professionals, and the environment.

Single-drug versus combination antimicrobial therapy in critically ill patients with hospital-acquired pneumonia and ventilator-associated pneumonia due to Gram-negative pathogens: a multicenter retrospective cohort study

KEY MESSAGES

In this study including 391 critically ill patients with nosocomial pneumonia due to Gram-negative pathogens, combination therapy was not associated with a reduced hazard of death at Day 28 or a greater likelihood of clinical cure at Day 14. No over-risk of AKI was observed in patients receiving combination therapy.

BACKGROUND

The benefits and harms of combination antimicrobial therapy remain controversial in critically ill patients with hospital-acquired pneumonia (HAP), ventilated HAP (vHAP) or ventilator-associated pneumonia (VAP) involving Gram-negative bacteria.

METHODS

We included all patients in the prospective multicenter OutcomeRea database with a first HAP, vHAP or VAP due to a single Gram-negative bacterium and treated with initial adequate single-drug or combination therapy. The primary endpoint was Day-28 all-cause mortality. Secondary endpoints were clinical cure rate at Day 14 and a composite outcome of death or treatment-emergent acute kidney injury (AKI) at Day 7. The average effects of combination therapy on the study endpoints were investigated through inverse probability of treatment-weighted regression and multivariable regression models. Subgroups analyses were performed according to the resistance phenotype of the causative pathogens (multidrug-resistant or not), the pivotal (carbapenems or others) and companion (aminoglycosides/polymyxins or others) drug classes, the duration of combination therapy (< 3 or ≥ 3 days), the SOFA score value at pneumonia onset (< 7 or ≥ 7 points), and in patients with pneumonia due to non-fermenting Gram-negative bacteria, pneumonia-related bloodstream infection, or septic shock.

RESULTS

Among the 391 included patients, 151 (38.6%) received single-drug therapy and 240 (61.4%) received combination therapy. VAP (overall, 67.3%), vHAP (16.4%) and HAP (16.4%) were equally distributed in the two groups. All-cause mortality rates at Day 28 (overall, 31.2%), clinical cure rate at Day 14 (43.7%) and the rate of death or AKI at Day 7 (41.2%) did not significantly differ between the groups. In inverse probability of treatment-weighted analyses, combination therapy was not independently associated with the likelihood of all-cause death at Day 28 (adjusted odd ratio [aOR], 1.14; 95% confidence interval [CI] 0.73-1.77; P = 0.56), clinical cure at Day 14 (aOR, 0.79; 95% CI 0.53-1.20; P = 0.27) or death or AKI at Day 7 (aOR, 1.07; 95% CI 0.71-1.63; P = 0.73). Multivariable regression models and subgroup analyses provided similar results.

CONCLUSIONS

Initial combination therapy exerts no independent impact on Day-28 mortality, clinical cure rate at Day 14, and the hazard of death or AKI at Day 7 in critically ill patients with mono-bacterial HAP, vHAP or VAP due to Gram-negative bacteria.

Carbapenems versus β-lactam and β-lactamase inhibitors for treatment of nosocomial pneumonia: A systematic review and meta-analysis

Background

Carbapenems and β-lactam and β-lactamase inhibitors (BLBLIs) have been used empirically in nosocomial pneumonia, but their efficacy and safety are controversial.

Objective

We carried out a systematic review with meta-analysis to evaluate the efficacy and safety of carbapenems versus BLBLIs against nosocomial pneumonia.

Methods

PubMed, Embase, Cochrane Central Register of Controlled Trials, CNKI, Wangfang, VIP and Sinomed were searched systematically through April 29, 2023 for clinical trials comparing carbapenems with BLBLIs for treatment of nosocomial pneumonia. Random-effects models were used to evaluate the impact of treatment on the risk ratio (RR) of all-cause mortality, clinical response, microbiologic response, resistance by Pseudomonas aeruginosa, adverse effects (AEs), and serious adverse effects. The quality of the evidence was assessed with the Cochrane risk of bias tool. The review was registerted in the INPLASY (INPLASY202340113).

Results

Seven randomized controlled trials containing 3306 patients met our inclusion criteria Our meta-analysis showed no significant difference in all-cause mortality (RR = 0.88, 95% confidence interval [CI] = 0.75-1.03, I2 = 0%) or clinical cure (1.02, 0.96-1.09, 30%) or clinical failure (1.19, 0.97-1.47, 0%) or microbiologic clinical cure (0.98, 0.89-1.06, 40%) or Pseudomonas aeruginosa resistance (RR 2.43, CI 0.86-6.81, 49%, P = 0.09) or adverse events (0.98, 0.93-1.02, 0%) between carbapenems groups versus BLBLIs groups, but a significant difference was found for severe adverse events (RR 0.83, CI 0.73-0.94, 0%).

Conclusion

Differences in the prevalence of mortality, clinical cure, or clinical failure were not observed between carbapenems groups versus BLBLIs groups in terms of nosocomial pneumonia. The use of carbapenems was linked to a tendency towards the emergence of P. aeruginosa resistance, however, no statistically significant difference was observed.

Multi-drug resistant Pseudomonas aeruginosa: a 2019-2020 single center retrospective case control study

Multi-drug resistance in the post COVID-19 world is a growing concern. The objective of this study was to describe temporal trends and explore independent risk factors for the isolation of multi-drug resistant (MDR) P. aeruginosa.

Methods

This was a retrospective case-control study of patients with P. aeruginosa isolates recovered from January 2019 to December 2020. MDR P. aeruginosa was defined as non-susceptibility to at least one agent in three or more anti-pseudomonal antimicrobial categories.

Results

In total, 258 unique isolates were identified. Prolonged hospitalization (P<0.001), prior antibiotic use (P<0.001), and respiratory sources (P<0.001) were strongly associated with the presence of MDR P. aeruginosa. From 2019 to 2020, there was a decrease in the total number of P. aeruginosa isolates but a significant increase in the proportion of MDR P. aeruginosa isolates (P=0.015).

Conclusions

Over a period that coincided with the COVID-19 pandemic, there was an increased proportion of MDR P. aeruginosa isolates from hospitalized patients. Improved identification of patients at risk for MDR P. aeruginosa could facilitate appropriate empiric antibiotic decisions like dual anti-pseudomonal therapy. The features of the COVID-19 outbreak that had a severe impact on patient care and that may have affected drug resistance in other respiratory pathogens should be explored.

Ventilator-Associated Pneumonia in COVID-19 Patients Admitted in Intensive Care Units: Relapse, Therapeutic Failure and Attributable Mortality-A Multicentric Observational Study from the OutcomeRea Network

Introduction: Ventilator-associated pneumonia (VAP) incidence is high among critically ill COVID-19 patients. Its attributable mortality remains underestimated, especially for unresolved episodes. Indeed, the impact of therapeutic failures and the determinants that potentially affect mortality are poorly evaluated. We assessed the prognosis of VAP in severe COVID-19 cases and the impact of relapse, superinfection, and treatment failure on 60-day mortality. Methods: We evaluated the incidence of VAP in a multicenter prospective cohort that included adult patients with severe COVID-19, who required mechanical ventilation for ≥48 h between March 2020 and June 2021. We investigated the risk factors for 30-day and 60-day mortality, and the factors associated with relapse, superinfection, and treatment failure. Results: Among 1424 patients admitted to eleven centers, 540 were invasively ventilated for 48 h or more, and 231 had VAP episodes, which were caused by Enterobacterales (49.8%), P. aeruginosa (24.8%), and S. aureus (22%). The VAP incidence rate was 45.6/1000 ventilator days, and the cumulative incidence at Day 30 was 60%. VAP increased the duration of mechanical ventilation without modifying the crude 60-day death rate (47.6% vs. 44.7% without VAP) and resulted in a 36% increase in death hazard. Late-onset pneumonia represented 179 episodes (78.2%) and was responsible for a 56% increase in death hazard. The cumulative incidence rates of relapse and superinfection were 45% and 39.5%, respectively, but did not impact death hazard. Superinfection was more frequently related to ECMO and first episode of VAP caused by non-fermenting bacteria. The risk factors for treatment failure were an absence of highly susceptible microorganisms and vasopressor need at VAP onset. Conclusions: The incidence of VAP, mainly late-onset episodes, is high in COVID-19 patients and associated with an increased risk of death, similar to that observed in other mechanically ventilated patients. The high rate of VAP due to difficult-to-treat microorganisms, pharmacokinetic alterations induced by renal replacement therapy, shock, and ECMO likely explains the high cumulative risk of relapse, superinfection, and treatment failure.

Nosocomial Pneumonia in the Mechanically Ventilated Patient

Ventilator-associated pneumonia (VAP) is a common complication occurring in critically ill patients who are mechanically ventilated and is the leading cause of nosocomial infection-related death. Etiologic agents for VAP widely differ based on the population of intensive care unit patients, duration of hospital stay, and prior antimicrobial therapy. VAP due to multidrug-resistant pathogens is associated with the highest morbidity and mortality, likely due to delays in appropriate antimicrobial treatment. International guidelines are currently available to guide diagnostic and therapeutic strategies. VAP can be prevented through various pharmacological and non-pharmacological interventions, which are more effective when grouped as bundles. When VAP is clinically suspected, diagnostic strategies should include early collection of respiratory samples to guide antimicrobial therapy. Empirical treatment should be based on the most likely etiologic microorganisms and antibiotics likely to be active against these microorganisms. Response to therapy should be reassessed after 3 to 5 days and antimicrobials adjusted or de-escalated to reduce the burden of the disease. Finally, considering that drug resistance is increasing worldwide, several novel antibiotics are being tested to efficiently treat VAP in the coming decades.

Risk Factors and Algorithms for the Empirical Treatment of Hospital-Acquired Pneumonia and Ventilator-Associated Pneumonia

Hospital-acquired pneumonia (HAP) and ventilator-associated pneumonia (VAP) continue to be major concerns for morbidity and mortality, especially in patients treated in the intensive care unit. With the rise in multidrug-resistant organisms, HAP and VAP treatment is challenged by the need for early appropriate treatment, with broad-spectrum agents, while still being aware of the principles of antibiotic stewardship. The two major society guidelines proposed a series of risk factors in their most recent guidelines to help identify patients who can most benefit from narrow- or broad-spectrum initial empiric antibiotic therapy. The guidelines reveal differences in the proposed risk factors and treatment approaches, as well as major similarities.

Management of pneumonia in critically ill patients

Severe pneumonia is associated with high mortality (short and long term), as well as pulmonary and extrapulmonary complications. Appropriate diagnosis and early initiation of adequate antimicrobial treatment for severe pneumonia are crucial in improving survival among critically ill patients. Identifying the underlying causative pathogen is also critical for antimicrobial stewardship. However, establishing an etiological diagnosis is challenging in most patients, especially in those with chronic underlying disease; those who received previous antibiotic treatment; and those treated with mechanical ventilation. Furthermore, as antimicrobial therapy must be empiric, national and international guidelines recommend initial antimicrobial treatment according to the location's epidemiology; for patients admitted to the intensive care unit, specific recommendations on disease management are available. Adherence to pneumonia guidelines is associated with better outcomes in severe pneumonia. Yet, the continuing and necessary research on severe pneumonia is expansive, inviting different perspectives on host immunological responses, assessment of illness severity, microbial causes, risk factors for multidrug resistant pathogens, diagnostic tests, and therapeutic options.

The Epidemiology and Pathogenesis and Treatment of Pseudomonas aeruginosa Infections: An Update

Pseudomonas aeruginosa is a Gram-negative bacterial pathogen that is a common cause of nosocomial infections, particularly pneumonia, infection in immunocompromised hosts, and in those with structural lung disease such as cystic fibrosis. Epidemiological studies have identified increasing trends of antimicrobial resistance, including multi-drug resistant (MDR) isolates in recent years. P. aeruginosa has several virulence mechanisms that increase its ability to cause severe infections, such as secreted toxins, quorum sensing and biofilm formation. Management of P. aeruginosa infections focuses on prevention when possible, obtaining cultures, and prompt initiation of antimicrobial therapy, occasionally with combination therapy depending on the clinical scenario to ensure activity against P. aeruginosa. Newer anti-pseudomonal antibiotics are available and are increasingly being used in the management of MDR P. aeruginosa.

The potential impact of the COVID-19 pandemic on global antimicrobial and biocide resistance: an AMR Insights global perspective

The COVID-19 pandemic presents a serious public health challenge in all countries. However, repercussions of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections on future global health are still being investigated, including the pandemic's potential effect on the emergence and spread of global antimicrobial resistance (AMR). Critically ill COVID-19 patients may develop severe complications, which may predispose patients to infection with nosocomial bacterial and/or fungal pathogens, requiring the extensive use of antibiotics. However, antibiotics may also be inappropriately used in milder cases of COVID-19 infection. Further, concerns such as increased biocide use, antimicrobial stewardship/infection control, AMR awareness, the need for diagnostics (including rapid and point-of-care diagnostics) and the usefulness of vaccination could all be components shaping the influence of the COVID-19 pandemic. In this publication, the authors present a brief overview of the COVID-19 pandemic and associated issues that could influence the pandemic's effect on global AMR.

Carbapenem Antibiotics for the Empiric Treatment of Nosocomial Pneumonia: A Systematic Review and Meta-analysis

BACKGROUND

Previous meta-analyses suggested that treating hospital-acquired pneumonia (HAP), including ventilator-associated pneumonia (VAP), with empiric carbapenems was associated with lower mortality rates but higher rates of clinical failure for pseudomonal pneumonia. This study was an updated meta-analysis with sensitivity analyses and meta-regression to better understand the impact of carbapenem use in HAP/VAP.

RESEARCH QUESTION

What is the efficacy of carbapenems for empiric treatment of nosocomial pneumonia?

STUDY DESIGN AND METHODS

Databases were searched for randomized controlled studies evaluating empiric treatment for HAP and/or VAP, and studies were included comparing carbapenem- vs non-carbapenem-containing regimens. The primary outcome was all-cause mortality. Secondary outcomes included subgroup stratification and resistance development.

RESULTS

Of 9,140 references, 20 trials enrolling 5,489 patients met inclusion criteria. For mortality, carbapenem use had a risk ratio (RR) of 0.84 (95% CI, 0.74-0.96; P = .01). Stratified according to VAP proportion (< 33%, 33%-66%, and > 66%), RRs were 0.95 (95% CI, 0.77-1.17; P = .66), 0.78 (95% CI, 0.57-1.07; P = .13), and 0.81 (95% CI, 0.65-0.99; P = .04), respectively. Stratified according to severity, only groups with Acute Physiology and Chronic Health Evaluation II scores < 14 and between 14 and 17 showed mortality benefit (RRs of 0.64 [95% CI, 0.45-0.92; P = .01] and 0.77 [95% CI, 0.61-0.97; P = .03]). Meta-regression did not show an association between Pseudomonas prevalence and mortality (P = .44). Carbapenem use showed a trend toward developing resistance (RR, 1.40; 95% CI, 0.95-2.06; P = .09) and a 96% probability of resistance emergence.

INTERPRETATION

Carbapenem-based empiric regimens were associated with lower mortality rates compared with non-carbapenems, largely driven by trials of VAP. The mortality effect was not observed in trials with high disease severity and was not associated with Pseudomonas. The mortality difference was observed mainly in studies that used ceftazidime as control. There was a trend toward increasing resistance associated with carbapenems.

TRIAL REGISTRY

International Prospective Register of Systematic Reviews; No. CRD42018093602; URL: https://www.crd.york.ac.uk/prospero/.

When are combinations of antibiotics clinically useful?

Antimicrobial resistance is a global crisis. Prescribing antibacterial combinations may be one way of reducing the development of resistance in target pathogens, as in the treatment of tuberculosis. Combinations may be useful for ascertaining synergy, broadening antimicrobial cover to reduce the risk of non-susceptibility, antimicrobial stewardship reasons, and immune modulation. The current research literature and/or prevailing global standards of clinical care suggest that combination therapy may be advantageous in: severe community-acquired pneumonia; severe hospital-acquired or ventilator-associated pneumonia or when there is a high risk of resistance in hospital-acquired or ventilator-associated pneumonia; multi-drug or extensively drug-resistant Gram-negative infections; and severe group A streptococcal infections. In other situations, combinations may be harmful. Overall, outside of tuberculosis, combination antibacterial therapy is likely to improve outcomes only in specific circumstances and there is little evidence to suggest that this prevents the development of bacterial resistance. Further high-quality research is essential.

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.

Chemical pharmacotherapy for hospital-acquired pneumonia in the elderly

INTRODUCTION

Hospital-acquired pneumonia (HAP) is a potentially serious infection that primarily affects older patients. The number of patients affected by multidrug-resistant (MDR) bacteria is increasing, including infection from strains of Staphylococcus aureus, Enterobacteriaceae, and Pseudomonas aeruginosa.

AREAS COVERED

This article focuses specifically on HAP, excluding patients afflicted by ventilator-associated pneumonia (VAP). The pathogenesis and clinical features of HAP in the elderly are discussed as well as specific drug pharmacokinetic and pharmacodynamic considerations in elderly patients. The current recommended guidelines for the management of HAP are also discussed. Finally, the authors provide evidence on the empirical therapy used for the treatment of HAP and widely consider specific-pathogen treatment of HAP in elderly patients.

EXPERT OPINION

In patients not at risk of MDR organism infection, antibiotics including piperacillin-tazobactam, cefepime, carbapenems or fluorquinolones are recommended. However, the emergence of MDR organisms as causal agents of HAP makes it necessary to accurately assess risk factors to these pathogens and revise our knowledge on specific antimicrobial susceptibility patterns from each institution. The authors believe that broader-spectrum empiric antibiotic therapies that target P. aeruginosa and methicillin-resistant S. aureus are best recommended in elderly patients at risk of HAP infection by MDR strains.

Therapies for multidrug resistant and extensively drug-resistant non-fermenting gram-negative bacteria causing nosocomial infections: a perilous journey toward 'molecularly targeted' therapy

INTRODUCTION

Non-fermenting Gram-negative bacilli are at the center of the antimicrobial resistance epidemic. Acinetobacter baumannii and Pseudomonas aeruginosa are both designated with a threat level to human health of 'serious' by the Centers for Disease Control and Prevention. Two other major non-fermenting Gram-negative bacilli, Stenotrophomonas maltophilia and Burkholderia cepacia complex, while not as prevalent, have devastating effects on vulnerable populations, such as those with cystic fibrosis, as well as immunosuppressed or hospitalized patients. Areas covered: In this review, we summarize the clinical impact, presentations, and mechanisms of resistance of these four major groups of non-fermenting Gram-negative bacilli. We also describe available and promising novel therapeutic options and strategies, particularly combination antibiotic strategies, with a focus on multidrug resistant variants. Expert commentary: We finally advocate for a therapeutic approach that incorporates in vitro antibiotic susceptibility testing with molecular and genotypic characterization of mechanisms of resistance, as well as pharmacokinetics and pharmacodynamics (PK/PD) parameters. The goal is to begin to formulate a precision medicine approach to antimicrobial therapy: a clinical-decision making model that integrates bacterial phenotype, genotype and patient's PK/PD to arrive at rationally-optimized combination antibiotic chemotherapy regimens tailored to individual clinical scenarios.

Nosokomiale Pneumonie

Nosokomiale Infektionen betreffen nach postoperativen Entzündungen von Wunden und Harnwegsinfektion am dritthäufigsten die unteren Atemwege. Die Pneumonie ist dabei die häufigste nosokomiale Atemwegsinfektion. Sie tritt überwiegend bei invasiv beatmeten Patienten auf. Zunehmend werden nosokomiale Infektionen durch multiresistente Keime hervorgerufen, was das Risiko einer inadäquaten initialen antiinfektiven Therapie erhöht. Die antiinfektive Therapie sollte bereits im Verdachtsfall begonnen werden. Die Diagnose ist im Verlauf kritisch zu überprüfen. Bestätigt sich eine nosokomiale Pneumonie nicht, sollte die antiinfektive Therapie vorzeitig beendet werden. Für die beatmungsassoziierte Pneumonie wurden verschiedene präventiv wirksame Maßnahmenbündel untersucht, mit deren Hilfe die Pneumonierate um über 50 % gesenkt werden konnte.

Treatment of Achromobacter Ventilator-Associated Pneumonia in Critically Ill Trauma Patients

BACKGROUND

Achromobacter sp are nonfermenting Gram-negative bacilli (NFGNB) that rarely cause severe infections, including ventilator-associated pneumonia (VAP). Data on the treatment of Achromobacter pneumonia are very limited, and the organism has been associated with a high mortality rate. Thus, more data are needed on treating this organism.

OBJECTIVE

To evaluate the treatment of Achromobacter VAP in critically ill trauma patients.

METHODS

This retrospective, observational study evaluated critically ill trauma patients who developed Achromobacter VAP. A previously published pathway for the diagnosis and management of VAP was used according to routine patient care. This included the use of quantitative bronchoscopic bronchoalveolar lavage cultures to definitively diagnose VAP.

RESULTS

A total of 37 episodes of Achromobacter VAP occurred in 34 trauma intensive care unit patients over a 15-year period. The most commonly used definitive antibiotics were imipenem/cilastatin, cefepime, or trimethoprim/sulfamethoxazole. The primary outcome of clinical success was achieved in 32 of 37 episodes (87%). This is similar to previous studies of other NFGNB VAP (eg, Pseudomonas, Acinetobacter) from the study center. Microbiological success was seen in 21 of 28 episodes (75%), and VAP-related mortality was 9% (3 of 34 patients).

CONCLUSIONS

Achromobacter is a rare but potentially serious cause of VAP in critically ill patients. In this study, there was an acceptable success rate compared with other causes of NFGNB VAP in this patient population.

An Update on Aerosolized Antibiotics for Treating Hospital-Acquired and Ventilator-Associated Pneumonia in Adults

OBJECTIVE

A significant percentage of patients with hospital-acquired pneumonia (HAP) and ventilator-associated pneumonia (VAP) have poor outcomes with intravenous antibiotics. It is not clear if adding aerosolized antibiotics improves treatment. This review is an update on using aerosolized antibiotics for treating HAP/VAP in adults.

DATA SOURCES

PubMed search using the terms "aerosolized antibiotics pneumonia," "nebulized antibiotics pneumonia," and "inhaled antibiotics pneumonia." Reference lists from identified articles were also searched.

STUDY SELECTION AND DATA EXTRACTION

Clinical studies of aerosolized antibiotics for treating HAP/VAP in adults from July 2010 to March 2017. This article updates a previous review on this topic written in mid-2010.

DATA SYNTHESIS

The size and quality of studies have improved dramatically in the recent time period compared to previous studies. However, there still are not large randomized controlled trials available. Colistin and aminoglycosides were the most commonly studied agents, and the most common pathogens were Pseudomonas and Acinetobacter. The clinical efficacy of adding aerosolized antibiotics was mixed. Approximately half of the studies showed better outcomes, and none showed worse outcomes. Aerosolized antibiotics appear to be relatively safe, though pulmonary adverse events can occur. Attention to proper administration technique in mechanically ventilated patients is required, including the use of vibrating plate nebulizers.

CONCLUSIONS

Adding aerosolized antibiotics to intravenous antibiotics may improve the outcomes of adult patients with HAP/VAP in some settings. It seems reasonable to add aerosolized antibiotics in patients with multidrug-resistant organisms or who appear to be failing therapy. Clinicians should pay attention to potential adverse events and proper administration technique.

Use of Gentamicin as Empiric Coverage for Ventilator-Associated Pneumonia: The "Con" Perspective

BACKGROUND

Gentamicin is used commonly as an empiric antibiotic prior to culture evidence in the treatment of ventilator-associated pneumonia (VAP) in surgical patients.

METHODS

The published literature on the use of gentamicin for empiric therapy in VAP was reviewed and in combination with the author's personal experience, an evaluation has been made about the indications for the use of this antibiotic in VAP.

RESULTS

Empiric gentamicin use appears to benefit less than 1% of patients in the treatment of presumptive VAP. The problematic pharmacokinetics of gentamicin use in this patient population combined with potential toxicity from the drug can be observed to yield greater risks than benefits in this clinical situation when published evidence is reviewed.

CONCLUSION

There is no definitive evidence to support empiric use of gentamicin in the treatment of VAP when evaluated on a cost-effective basis.

Strategies to enhance rational use of antibiotics in hospital: a guideline by the German Society for Infectious Diseases

Introduction

In the time of increasing resistance and paucity of new drug development there is a growing need for strategies to enhance rational use of antibiotics in German and Austrian hospitals. An evidence-based guideline on recommendations for implementation of antibiotic stewardship (ABS) programmes was developed by the German Society for Infectious Diseases in association with the following societies, associations and institutions: German Society of Hospital Pharmacists, German Society for Hygiene and Microbiology, Paul Ehrlich Society for Chemotherapy, The Austrian Association of Hospital Pharmacists, Austrian Society for Infectious Diseases and Tropical Medicine, Austrian Society for Antimicrobial Chemotherapy, Robert Koch Institute.

Materials and methods

A structured literature research was performed in the databases EMBASE, BIOSIS, MEDLINE and The Cochrane Library from January 2006 to November 2010 with an update to April 2012 (MEDLINE and The Cochrane Library). The grading of recommendations in relation to their evidence is according to the AWMF Guidance Manual and Rules for Guideline Development.

Conclusion

The guideline provides the grounds for rational use of antibiotics in hospital to counteract antimicrobial resistance and to improve the quality of care of patients with infections by maximising clinical outcomes while minimising toxicity. Requirements for a successful implementation of ABS programmes as well as core and supplemental ABS strategies are outlined. The German version of the guideline was published by the German Association of the Scientific Medical Societies (AWMF) in December 2013.

Antimicrobial combination treatment including ciprofloxacin decreased the mortality rate of Pseudomonas aeruginosa bacteraemia: a retrospective cohort study

Ineffective antimicrobial therapy of Pseudomonas aeruginosa bacteraemia increases mortality. Recent studies have proposed the use of antimicrobial combination therapy composed of a beta-lactam with either ciprofloxacin or tobramycin. To determine if combination therapy correlates to lower mortality and is superior compared to monotherapy, we investigated the effect of antimicrobial treatment regimens on 30-day mortality in a cohort with Pseudomonas aeruginosa bacteraemia. All cases of P. aeruginosa bacteraemia (n = 292) in southwest Skåne County, Sweden (years 2005-2010, adult population 361,112) and the whole county (2011-2012, 966,130) were identified. Available medical and microbiological records for persons aged 18 years or more were reviewed (n = 235). Antimicrobial therapy was defined as empiric at admission or definitive after culture results and was correlated to 30-day mortality in a multivariate regression model. The incidence and mortality rates were 8.0 per 100,000 adults and 22.9% (67/292), respectively. As expected, multiple comorbidities and high age were associated with mortality. Adequate empiric or definitive antipseudomonal treatment was associated with lower mortality than other antimicrobial alternatives (empiric p = 0.02, adj. p = 0.03; definitive p < 0.001, adj. p = 0.007). No difference in mortality was seen between empiric antipseudomonal monotherapy or empiric combination therapy. However, definitive combination therapy including ciprofloxacin correlated to lower mortality than monotherapy (p = 0.006, adj. p = 0.003), whereas combinations including tobramycin did not. Our results underline the importance of adequate antipseudomonal treatment. These data also suggest that P. aeruginosa bacteraemia should be treated with an antimicrobial combination including ciprofloxacin when susceptible.

Management of infections associated with neurocritical care

The reported incidence of hospital-acquired infections (HAIs) in the neurointensive care unit (NICU) ranges from 20% to 30%. HAIs in US hospitals cost between $28 and $45 billion per year in direct medical costs. These infections are associated with increased length of hospital stay and increased morbidity and mortality. Infection risk is increased in NICU patients due to medication side-effects, catheter and line placement, neurosurgical procedures, and acquired immune suppression secondary to steroid/barbiturate use and brain injury itself. Some of these infections may be preventable but many are not. Their appearance do not always constitute a failure of prevention or physician error. Neurointensivists require indepth knowledge of common nosocomial infections, their diagnosis and treatment, and an approach to evidence-based practices that improve processes of care and reduce HAIs.

Impact of Probiotics for Reducing Infections in Veterans (IMPROVE): Study protocol for a double-blind, randomized controlled trial to reduce carriage of Staphylococcus aureus

BACKGROUND

Staphylococcus aureus (S. aureus) is an organism of great public health importance, causing 20,000 deaths annually. Decolonization of patients with S. aureus may prevent infections, yet current options are limited to antimicrobials that promote antibiotic resistance and can cause adverse side effects. Probiotics have potential to reduce colonization of pathogenic bacteria, representing a promising alternative for S. aureus decolonization, but thus far lack rigorous evaluation.

METHODS

Potential subjects were recruited from inpatient and outpatient settings within a VA medical center and screened for S. aureus gastrointestinal (GI) or extra-GI colonization using swabs at multiple body sites. Positive, eligible, consenting participants were stratified by colonization site and randomized in a 1:1 ratio to 4-weeks of daily placebo or Lactobacillus rhamnosus (L. rhamnosus) HN001 probiotic treatment. Blood and stool samples, and treatment adherence reports were collected from each subject throughout the study, along with a final set of swabs at study completion to detect S. aureus carriage. The outcomes of this study are GI or extra-GI carriage by S. aureus at the end of 4weeks of therapy, change in phagocytic activity of polymorphonuclear cells from pre-intervention to post-intervention, and symptomatic S. aureus infection at any site during the study period.

CONCLUSION

114 participants have been recruited for this study. Analysis of outcomes is underway. This is the first clinical trial to examine the efficacy of L. rhamnosus HN001 for decolonization of S. aureus, and investigates the mechanism by which L. rhamnosus HN001 mediates its effect on S. aureus colonization. ClinicalTrials.govIdentifier NCT01321606.

Management of Adults With Hospital-acquired and Ventilator-associated Pneumonia: 2016 Clinical Practice Guidelines by the Infectious Diseases Society of America and the American Thoracic Society

It is important to realize that guidelines cannot always account for individual variation among patients. They are not intended to supplant physician judgment with respect to particular patients or special clinical situations. IDSA considers adherence to these guidelines to be voluntary, with the ultimate determination regarding their application to be made by the physician in the light of each patient's individual circumstances.These guidelines are intended for use by healthcare professionals who care for patients at risk for hospital-acquired pneumonia (HAP) and ventilator-associated pneumonia (VAP), including specialists in infectious diseases, pulmonary diseases, critical care, and surgeons, anesthesiologists, hospitalists, and any clinicians and healthcare providers caring for hospitalized patients with nosocomial pneumonia. The panel's recommendations for the diagnosis and treatment of HAP and VAP are based upon evidence derived from topic-specific systematic literature reviews.

An Argument for the Use of Aminoglycosides in the Empiric Treatment of Ventilator-Associated Pneumonia

BACKGROUND

Appropriate empiric antibiotic therapy for ventilator-associated pneumonia improves outcomes. Controversy exists regarding the inclusion of aminoglycosides in empiric therapeutic regimens.

METHODS

The Ovid and Cochrane databases were searched for relevant literature regarding the use of aminoglycosides in combination therapy for ventilator-associated pneumonia. The data supporting the use of aminoglycosides in certain populations and strategies to limit toxicity are summarized.

RESULTS

In patients at high risk of infection with antibiotic-resistant gram-negative bacilli and in those with severe illness, aminoglycosides improve clinical outcomes. In critically ill populations, short-duration therapy and high-dose extended-interval dosing of aminoglycosides can improve therapeutic efficacy while limiting nephrotoxicity.

CONCLUSIONS

In selected populations using appropriate dosing strategies, aminoglycosides should be considered for empiric treatment of ventilator-associated pneumonia.

Nebulized antibiotics for ventilator-associated pneumonia: a systematic review and meta-analysis

INTRODUCTION

Nebulized antibiotics are a promising new treatment option for ventilator-associated pneumonia. However, more evidence of the benefit of this therapy is required.

METHODS

The Medline, Scopus, EMBASE, Biological Abstracts, CAB Abstracts, Food Science and Technology Abstracts, CENTRAL, Scielo and Lilacs databases were searched to identify randomized controlled trials or matched observational studies that compared nebulized antibiotics with or without intravenous antibiotics to intravenous antibiotics alone for ventilator-associated pneumonia treatment. Two reviewers independently collected data and assessed outcomes and risk of bias. The primary outcome was clinical cure. Secondary outcomes were microbiological cure, ICU and hospital mortality, duration of mechanical ventilation, ICU length of stay and adverse events. A mixed-effect model meta-analysis was performed. Trial sequential analysis was used for the main outcome of interest.

RESULTS

Twelve studies were analyzed, including six randomized controlled trials. For the main outcome analysis, 812 patients were included. Nebulized antibiotics were associated with higher rates of clinical cure (risk ratio (RR) = 1.23; 95% confidence interval (CI), 1.05 to 1.43; I(2) = 34%; D(2) = 45%). Nebulized antibiotics were not associated with microbiological cure (RR = 1.24; 95% CI, 0.95 to 1.62; I(2) = 62.5), mortality (RR = 0.90; CI 95%, 0.76 to 1.08; I(2) = 0%), duration of mechanical ventilation (standardized mean difference = -0.10 days; 95% CI, -1.22 to 1.00; I(2) = 96.5%), ICU length of stay (standardized mean difference = 0.14 days; 95% CI, -0.46 to 0.73; I(2) = 89.2%) or renal toxicity (RR = 1.05; 95% CI, 0.70 to 1.57; I(2) = 15.6%). Regarding the primary outcome, the number of patients included was below the information size required for a definitive conclusion by trial sequential analysis; therefore, our results regarding this parameter are inconclusive.

CONCLUSIONS

Nebulized antibiotics seem to be associated with higher rates of clinical cure in the treatment of ventilator-associated pneumonia. However, the apparent benefit in the clinical cure rate observed by traditional meta-analysis does not persist after trial sequential analysis. Additional high-quality studies on this subject are highly warranted.

TRIAL REGISTRATION NUMBER

CRD42014009116 . Registered 29 March 2014.

Review on the Antimicrobial Resistance of Pathogens from Tracheal and Endotracheal Aspirates of Patients with Clinical Manifestations of Pneumonia in Bacolod City in 2013

Microbiological content specifically bacterial and fungal etiologies from tracheal aspirates in a tertiary hospital in Bacolod City was reviewed for baseline information. A total of 130 tracheal aspirates were subjected for culture to isolate and identify the pathogen and determine their susceptibilities to various antibiotics. Productions of certain enzymes responsible for antibiotic resistance like ESBL (Extended Spectrum Beta-Lactamase), metallo-β-lactamase, and carbapenemase were also studied. Out of 130 specimens, 69.23% were found to be positive for the presence of microorganisms. Most infections were from male patients aging 60 years and above, confined at the Intensive Care Units (ICU). Pseudomonas aeruginosa and Klebsiella pneumoniae were found to be the most frequent bacterial isolates and non-Candida albicans for fungal isolates, respectively. Among the various antibiotics tested, most isolates were found to be resistant to third generation cephalosporins and penicillins, but susceptible to aminoglycoside Amikacin. On the other hand, production of ESBL and carbapenemase was found to be common among members of Enterobacteriaceae especially K. pneumoniae.

Shortening the course of antibiotic treatment in the intensive care unit

Effective antimicrobial stewardship is an increasingly important concern for healthcare providers globally. Antibiotics are frequently prescribed for patients who develop sepsis in the intensive care unit and traditionally courses are prolonged, with uncertain benefit and probable harm. There is little evidence to support many guidelines recommending between 10 and 14 days, and a number of studies suggest substantially shorter courses of less than 7 days may suffice. Safely reducing course length is likely to depend on a number of preconditions, including thorough eradication of any septic foci; optimization of serum antibiotic concentrations, particularly when there is physiological derangement; and use of novel biomarkers such as procalcitonin. The critical care environment is well suited to this aim as patients are closely monitored. With these measures in place, it is reasonable to believe short antibiotic courses can safely be used for the majority of intensive care infections.

Ventilator-associated pneumonia: present understanding and ongoing debates

INTRODUCTION

Ventilator-associated pneumonia (VAP) is a common cause of nosocomial infection, and is related to significant utilization of health-care resources. In the past decade, new data have emerged about VAP epidemiology, diagnosis, treatment and prevention.

RESULTS

Classifying VAP strictly based on time since hospitalization (early- and late-onset VAP) can potentially result in undertreatment of drug-resistant organisms in ICUs with a high rate of drug resistance, and overtreatment for patients not infected with resistant pathogens. A combined strategy incorporating diagnostic scoring systems, such as the Clinical Pulmonary Infection Score (CPIS), and either a quantitative or qualitative microbiological specimen, plus serial measurement of biomarkers, leads to responsible antimicrobial stewardship. The newly proposed ventilator-associated events (VAE) surveillance definition, endorsed by the Centers for Disease Control and Prevention, has low sensitivity and specificity for diagnosing VAP and the ability to prevent VAE is uncertain, making it a questionable surrogate for the quality of ICU care. The use of adjunctive aerosolized antibiotic treatment can provide high pulmonary concentrations of the drug and may facilitate shorter durations of therapy for multi-drug-resistant pathogens. A group of preventive strategies grouped as a 'ventilator bundle' can decrease VAP rates, but not to zero, and several recent studies show that there are potential barriers to implementation of these prevention strategies.

CONCLUSION

The morbidity and mortality related to VAP remain high and, in the absence of a gold standard test for diagnosis, suspected VAP patients should be started on antibiotics based on recommendations per the 2005 ATS guidelines and knowledge of local antibiotic susceptibility patterns. Using a combination of clinical severity scores, biomarkers, and cultures might help with reducing the duration of therapy and achieving antibiotic de-escalation.

Antibiotic-resistant Pseudomonas aeruginosa: focus on care in patients receiving assisted ventilation

ABSTRACT: 

This article discusses ventilator-associated pneumonia caused by Pseudomonas aeruginosa. Ventilator-associated pneumonia caused by P. aeruginosa is one of the leading causes of morbidity and mortality in the intensive care unit, and nowadays it represents a major concern due to the increasing resistance rate of the pathogen to different classes of antibiotics. Here, the choice between a combination therapy and a monotherapy in the empirical setting is analyzed and discussed, by focusing on the recommendations of different published guidelines. Pros and cons of the different possible associations are analyzed and suggestions are given in light of the emergence of multidrug-resistant strains. Route of administration is also discussed, with an emphasis on the use of nebulized antibiotics. Optimal duration of treatment is an additional point of discussion, and explanations are provided for the suggested longer course compared with that of other etiologies.

Adult patients with nosocomial pneumonia: epidemiology, diagnosis, and treatment

BACKGROUND

Nosocomial pneumonia is among the most common types of infection in hospitalized patients. The increasing prevalence of multi-drug resistant organisms (MDROs) in recent years points to the need for an up-to-date clinical guideline.

METHODS

An interdisciplinary S3 guideline was created on the basis of a systematic literature review in the PubMed and Cochrane Library databases, with assessment and grading of the evidence according to the GRADE system.

RESULTS

9097 abstracts and 808 articles were screened in full text, and 22 recommendations were issued. It is recommended that any antimicrobial treatment should be preceded by a microbiological diagnostic evaluation with cultures of blood and respiratory samples. The diagnosis of nosocomial pneumonia should be suspected in any patient with a new or worsened pulmonary infiltrate who meets any two of the following three criteria: leucocyte count above 10,000 or below 4000/µL, temperature above 38.3°C, and/or the presence of purulent respiratory secretions. The initially calculated antimicrobial treatment should be begun without delay; it should be oriented to the locally prevailing resistance pattern, and its intensity should be a function of the risk of infection with MDROs. The initial treatment should be combination therapy if there is a high risk of MDRO infection and/or if the patient is in septic shock. In the new guideline, emphasis is laid on a strict de-escalation concept. In particular, antimicrobial treatment usually should not be continued for longer than eight days.

CONCLUSION

The new guideline's recommendations are intended to encourage rational use of antibiotics, so that antimicrobial treatment will be highly effective while the unnecessary selection of multi-drug-resistant organisms will be avoided.

Empirical Antibiotic Therapy for Ventilator-Associated Pneumonia

Ventilator-associated pneumonia (VAP) is the most common infectious complication in the intensive care unit. It can increase duration of mechanical ventilation, length of stay, costs, and mortality. Improvements in the administration of empirical antibiotic therapy have potential to reduce the complications of VAP. This review will discuss the current data addressing empirical antibiotic therapy and the effect on mortality in patients with VAP. It will also address factors that could improve the administration of empirical antibiotics and directions for future research.

β-Lactam plus aminoglycoside or fluoroquinolone combination versus β-lactam monotherapy for Pseudomonas aeruginosa infections: a meta-analysis

The objective of this review was to compare the effectiveness and safety of β-lactam combined with aminoglycoside or fluoroquinolone with that of β-lactam monotherapy for the treatment of Pseudomonas aeruginosa infections. We searched Scopus and PubMed databases and synthesised the outcomes of the individual studies in a meta-analysis. Both non-randomised studies and randomised controlled trials (RCTs) that evaluated outcomes of patients with P. aeruginosa infections receiving treatment with β-lactams alone or in combination with an aminoglycoside or a fluoroquinolone were included. Studies including patients with cystic fibrosis were excluded. Nineteen articles (eight RCTs) were included (1721 patients with P. aeruginosa infections). Patients receiving combination therapy had no difference in mortality compared with patients receiving β-lactam monotherapy either as definitive (risk ratio=0.97, 95% confidence interval 0.77-1.22) or as empirical treatment (1.02, 0.78-1.34). In the definitive treatment group, no difference in mortality was found between combination therapy and monotherapy for patients with bacteraemia (0.95, 0.67-1.34) or severe infections (0.96, 0.75-1.24). Patients receiving definitive combination therapy had non-significantly higher clinical cure compared with patients receiving β-lactam monotherapy (1.36, 0.99-1.86). A higher clinical cure rate was observed for patients receiving empirical treatment with combination therapy (1.23, 1.05-1.43). There was no difference in clinical cure either for RCTs (1.29, 0.91-1.83) or for non-randomised studies (1.18, 0.97-1.45). In conclusion, no benefit in mortality was observed in patients receiving combination therapy for P. aeruginosa infections. A well-designed multicentre RCT is warranted to address this important issue.

Combination therapy for treatment of infections with gram-negative bacteria

Combination antibiotic therapy for invasive infections with Gram-negative bacteria is employed in many health care facilities, especially for certain subgroups of patients, including those with neutropenia, those with infections caused by Pseudomonas aeruginosa, those with ventilator-associated pneumonia, and the severely ill. An argument can be made for empiric combination therapy, as we are witnessing a rise in infections caused by multidrug-resistant Gram-negative organisms. The wisdom of continued combination therapy after an organism is isolated and antimicrobial susceptibility data are known, however, is more controversial. The available evidence suggests that the greatest benefit of combination antibiotic therapy stems from the increased likelihood of choosing an effective agent during empiric therapy, rather than exploitation of in vitro synergy or the prevention of resistance during definitive treatment. In this review, we summarize the available data comparing monotherapy versus combination antimicrobial therapy for the treatment of infections with Gram-negative bacteria.

Continuing education: alternative approaches to optimizing antimicrobial pharmacodynamics in critically ill patients

Critical illness results in a constellation of physiologic changes that subsequently impact antibiotic pharmacokinetic and pharmacodynamic parameters. These changes can result in poorly treated infections that in turn lead to longer intensive care unit (ICU) and hospital stays, prolonged use of mechanical ventilation, and higher mortality rates. Research has expanded our understanding of antibiotic pharmacodynamics among ICU patients, and some investigators and clinicians have questioned traditional antibiotic dosing schemes among this population. Alternative dosing strategies to optimize antibiotic pharmacodynamics of aminoglycosides, beta-lactams, fluoroquinolones, and vancomycin have been explored. Appropriate duration of exposure to beta-lactam antibiotics has been recognized as an important parameter associated with successful treatment outcomes. To maximize this exposure, continuous infusions over a 24-hour period have resulted in higher clinical response rates and improved surrogate markers of infection. Equally as promising is the alternative of extending the infusion time to increase exposure while maintaining the same daily beta-lactam dose and frequency. Data from clinical trials have suggested that the area under the concentration-time curve to minimum inhibitory concentration ratio for aminoglycosides, fluoroquinolones, and vancomycin is a better correlate for successful treatment outcomes. Optimizing antibiotic pharmacodynamics by changing dosage methods should be considered in ICU patients to improve treatment response and success.

Infectious diseases in the critically ill patients

Infection is common in the critically ill and often results due to the severity of the patient's illness. Recent data suggest 51% of intensive care unit (ICU) patients are infected, and 71% receive antimicrobial therapy. Bacterial infection is the primary concern, although some fungal infections are opportunistic. Infection more than doubles the ICU mortality rate, and the costs associated with infection may be as high as 40% of total ICU expenditures. There are many contemporary antimicrobial resistance concerns that the critical care clinician must consider in managing the pharmacotherapy of infection. Methicillin resistance in Staphylococcus aureus, vancomycin resistance in Enterococci, beta-lactamase resistance in Enterobacteriaceae, multidrug resistance in Pseudomonas aeruginosa and Acinetobacter species, fluoroquinolone resistance in Escherichia coli, and fungal resistance are among the most common issues ICU clinician's must face in managing infection. Critical illness causes changes in pharmacokinetics that influence drug and dosing considerations. Absorption, distribution, metabolism, and excretion may all be affected by the various disease states that define critical illness. Several specific diseases are discussed, including ventilator-associated pneumonia, various fungal infections, gastrointestinal infections due to Clostridium difficile, urinary tract infections, and bloodstream infections. Within each disease section, discussion includes causes and prevention strategies, microbiology, evidence-based guidelines, and important caveats.

Combination antibiotic therapy for empiric and definitive treatment of gram-negative infections: insights from the Society of Infectious Diseases Pharmacists

The widespread emergence of antibiotic-resistant gram-negative organisms has compromised the utility of current treatment options for severe infections caused by these pathogens. The rate of gram-negative multidrug resistance is worsening, threatening the effectiveness of newer broad-spectrum antibiotic agents. Infections associated with multidrug-resistant Pseudomonas aeruginosa, Acinetobacter baumannii, and Enterobacteriaceae are having a substantial impact on hospital costs and mortality rates. The potential for these resistant gram-negative nosocomial pathogens must always be a primary consideration when selecting antibiotic therapy for critically ill patients. Empiric combination therapy directed at gram-negative pathogens is a logical approach for patients with suspected health care-associated infections, particularly those with risk factors for infections caused by multidrug-resistant pathogens. Although in vitro synergy tests have shown potential benefits of continued combination therapy, convincing clinical data that demonstrate a need for combination therapy once susceptibilities are known are lacking. Thus, deescalation to a single agent once susceptibilities are known is recommended for most patients and pathogens. Use of polymyxins, often in combination with other antimicrobials, may be necessary for salvage therapy.

Ventilator-associated pneumonia in burn patients: a cause or consequence of critical illness?

Infectious complications are a constant threat to thermally injured patients during hospitalizations and are a predominant cause of death. Most of the infections that develop in burn patients are nosocomial and of a pulmonary etiology. The bacteria that cause ventilator associated pneumonia (VAP) take advantage of the fact that uniquely among intensive care unit patients endotracheal intubation allows them a 'free' passage to the sterile lower airways; however, the combination of severe thermal injury (systemic immunosuppression) and inhalation injury (local immunosuppression and tissue injury) create an ideal environment for development of VAP. Thus, strategies directed at preventing and treating VAP in burn patients must address not only rapid extubation and VAP prevention bundles known to work in other intensive care unit populations, but therapies directed to more rapid wound healing and restoration of pulmonary patency.

Advances in the management of sepsis and the understanding of key immunologic defects

Anesthesiologists are increasingly confronting the difficult problem of caring for patients with sepsis in the operating room and in the intensive care unit. Sepsis occurs in more than 750,000 patients in the United States annually and is responsible for more than 210,000 deaths. Approximately 40% of all intensive care unit patients have sepsis on admission to the intensive care unit or experience sepsis during their stay in the intensive care unit. There have been significant advances in the understanding of the pathophysiology of the disorder and its treatment. Although deaths attributable to sepsis remain stubbornly high, new treatment algorithms have led to a reduction in overall mortality. Thus, it is important for anesthesiologists and critical care practitioners to be aware of these new therapeutic regimens. The goal of this review is to include practical points on important advances in the treatment of sepsis and provide a vision of future immunotherapeutic approaches.

Appraising contemporary strategies to combat multidrug resistant gram-negative bacterial infections--proceedings and data from the Gram-Negative Resistance Summit

The emerging problem of antibiotic resistance, especially among Gram-negative bacteria (GNB), has become a serious threat to global public health. Very few new antibacterial classes with activity against antibiotic-resistant GNB have been brought to market. Renewed and growing attention to the development of novel compounds targeting antibiotic-resistant GNB, as well as a better understanding of strategies aimed at preventing the spread of resistant bacterial strains and preserving the efficacy of existing antibiotic agents, has occurred. The Gram-Negative Resistance Summit convened national opinion leaders for the purpose of analyzing current literature, epidemiologic trends, clinical trial data, therapeutic options, and treatment guidelines related to the management of antibiotic-resistant GNB infections. After an in-depth analysis, the Summit investigators were surveyed with regard to 4 clinical practice statements. The results then were compared with the same survey completed by 138 infectious disease and critical care physicians and are the basis of this article.