Impact of the “Zero Resistance” program on acquisition of multidrug-resistant bacteria in patients admitted to Intensive Care Units in Spain. A prospective, intervention, multimodal, multicenter study / Impacto del Proyecto “Resistencia Zero” en la adquisición de bacterias multirresistentes en pacientes ingresados en Unidades de Cuidados Intensivos en España. Estudio de intervención, multimodal y multicéntrico

Objective To assess the impact of a multimodal interventional project (“Zero Resistance”) on the acquisition of multidrug-resistant bacteria (MDR-B) during the patient’s ICU stay. Design Prospective, open-label, interventional, multicenter study. Setting 103 ICUs. Patients Critically ill patients admitted to the ICUs over a 27-month period. Interventions Implementation of a bundle of 10 recommendations to prevent emergence and spread of MDR-B in the ICU. Main variable of interest Rate of patients acquiring MDR-B during their ICU stay, with differentiation between colonization and infection. Results A total of 139,505 patients were included. In 5409 (3.9%) patients, 6020 MDR-B on ICU admission were identified, and in 3648 (2.6%) patients, 4269 new MDR-B during ICU stay were isolated. The rate of patients with MDR-B detected on admission increased significantly (IRR 1.43, 95% CI 1.31–1.56) (p<0.001) during the study period, with an increase of 32.2% between the initial and final monthly rates. On the contrary, the rate of patients with MDR-B during ICU stay decreased non-significantly (IRR 0.93, 95% CI 0.83–1.03) (p=0.174), with a 24.9% decrease between initial and final monthly rates. According to the classification into colonization or infection, there was a highly significant increase of MDR-B colonizations detected on admission (IRR 1.69, 95% CI 1.52–1.83; p<0.0001) and a very significant decrease of MDR-B-infections during ICU stay (IRR 0.67, 95% CI 0.57–0.80, p<0.0001). Conclusions The implementation of ZR project-recommendations was associated with a significantly reduction an infection produced by MDR-B acquired during the patient’s ICU stay (AU)

Objetivo Evaluar el impacto de un proyecto de intervención multimodal (“Resistencia Zero”, RZ) en la adquisición de bacterias multirresistentes (BMR) durante la estancia en UCI. Diseño Estudio prospectivo, abierto, intervencionista, multicéntrico. Ámbito 103 UCI. Pacientes Pacientes críticos ingresados en UCI, durante un período de 27 meses. Intervenciones Implementación de un paquete de 10 recomendaciones para prevenir la aparición y propagación de BMR en UCI. Principal variable de interés Tasa de pacientes que adquieren BMR durante su estancia en UCI, diferenciando entre colonización e infección. Resultados Se incluyeron 139.505 pacientes. En 5.409(3,9%), se identificaron 6.020 BMR al ingreso y en 3.648(2,6%), se aislaron 4.269 nuevas BMR durante la estancia en UCI. La tasa de pacientes con BMR detectadas al ingreso aumentó significativamente (IRR 1,43, IC 95% 1,31–1,56) (p<0,001) durante el periodo de estudio, con un incremento del 32,2% entre las tasas mensuales inicial y final. Por el contrario, la tasa de pacientes con BMR detectadas durante la estancia en UCI disminuyó, no significativamente (IRR 0,93, IC 95% 0,83–1,03) (p=0,174), con una disminución del 24,9% entre las tasas mensuales iniciales y finales. Según la clasificación en colonización o infección, hubo un aumento significativo de colonizaciones por BMR detectadas al ingreso (IR 1,69, IC 95% 1,52–1,83; p<0,0001) y una disminución significativa de infecciones producidas por BMR adquiridas durante la estancia en UCI (IR 0,67, IC 95% 0,57–0,80, p<0,0001). Conclusiones La implementación de las recomendaciones del proyecto RZ se asoció con una reducción significativa de pacientes con infecciones por BMR adquiridas en UCI (AU)

Severe community-acquired Streptococcus pneumoniae bacterial meningitis: clinical and prognostic picture from the intensive care unit.

BACKGROUND: Severe community-acquired pneumococcal meningitis is a medical emergency. The aim of the present investigation was to evaluate the epidemiology, management and outcomes of this condition. METHODS: This was a retrospective, observational and multicenter cohort study. Sixteen Spanish intensive care units (ICUs) were included. Demographic, clinical and microbiological variables from patients with Streptococcus pneumoniae meningitis admitted to ICU were evaluated. Clinical response was evaluated at 72 h after antibiotic treatment initiation, and meningitis complications, length of stay and 30-day mortality were also recorded. RESULTS: In total, 255 patients were included. Cerebrospinal fluid (CSF) culture was positive in 89.7%; 25.7% were non-susceptible to penicillin, and 5.2% were non-susceptible to ceftriaxone or cefotaxime. The most frequent empiric antibiotic regimen was third-generation cephalosporin (47.5%) plus vancomycin (27.8%) or linezolid (12.9%). A steroid treatment regimen was administered to 88.6% of the patients. Clinical response was achieved in 65.8% of patients after 72 h of antibiotic treatment. Multivariate analysis identified two factors associated with early treatment failure: invasive mechanical ventilation (OR 10.74; 95% CI 3.04-37.95, p < 0.001) and septic shock (OR 1.18; 95% CI 1.03-1.36, p = 0.017). The 30-day mortality rate was 13.7%. Only three factors were independently associated with 30-day mortality: delay in start of antibiotic treatment (OR 18.69; 95% CI 2.13-163.97, p = 0.008), Sepsis-related Organ Failure Assessment (SOFA) score (OR 1.36; 95% CI 1.12-1.66, p = 0.002) and early treatment failure (OR 21.75 (3.40-139.18), p = 0.001). Neurological complications appeared in 124 patients (48.63%). CONCLUSIONS: Mortality rate in critically ill patients with pneumococcal meningitis is lower than previously reported. Delay in antibiotic treatment following admission is the only amendable factor associated with mortality.

Impact of the "Zero Resistance" program on acquisition of multidrug-resistant bacteria in patients admitted to Intensive Care Units in Spain. A prospective, intervention, multimodal, multicenter study.

OBJECTIVE: To assess the impact of a multimodal interventional project ("Zero Resistance") on the acquisition of multidrug-resistant bacteria (MDR-B) during the patient's ICU stay. DESIGN: Prospective, open-label, interventional, multicenter study. SETTING: 103 ICUs. PATIENTS: Critically ill patients admitted to the ICUs over a 27-month period. INTERVENTIONS: Implementation of a bundle of 10 recommendations to prevent emergence and spread of MDR-B in the ICU. MAIN VARIABLE OF INTEREST: Rate of patients acquiring MDR-B during their ICU stay, with differentiation between colonization and infection. RESULTS: A total of 139,505 patients were included. In 5409 (3.9%) patients, 6020 MDR-B on ICU admission were identified, and in 3648 (2.6%) patients, 4269 new MDR-B during ICU stay were isolated. The rate of patients with MDR-B detected on admission increased significantly (IRR 1.43, 95% CI 1.31-1.56) (p<0.001) during the study period, with an increase of 32.2% between the initial and final monthly rates. On the contrary, the rate of patients with MDR-B during ICU stay decreased non-significantly (IRR 0.93, 95% CI 0.83-1.03) (p=0.174), with a 24.9% decrease between initial and final monthly rates. According to the classification into colonization or infection, there was a highly significant increase of MDR-B colonizations detected on admission (IRR 1.69, 95% CI 1.52-1.83; p<0.0001) and a very significant decrease of MDR-B-infections during ICU stay (IRR 0.67, 95% CI 0.57-0.80, p<0.0001). CONCLUSIONS: The implementation of ZR project-recommendations was associated with a significantly reduction an infection produced by MDR-B acquired during the patient's ICU stay.

Study of risk factors for healthcare-associated infections in acute cardiac patients using categorical principal component analysis (CATPCA).

Using categorical principal component analysis, we aimed to determine the relationship between health care-associated infections (HAIs) and diagnostic categories (DCs) in patients with acute heart disease using data collected in the Spanish prospective ENVIN-HELICS intensive care registry over a 10-year period (2005-2015). A total of 69,876 admissions were included, of which 5597 developed HAIs. Two 2-component CATPCA models were developed. In the first model, all cases were included; the first component was determined by the duration of the invasive devices, the ICU stay, the APACHE II score and the HAIs; the second component was determined by the type of admission (medical or surgical) and by the DCs. No clear association between DCs and HAIs was found. Cronbach's alpha was 0.899, and the variance accounted for (VAF) was 52.5%. The second model included only admissions that developed HAIs; the first component was determined by the duration of the invasive devices and the ICU stay; the second component was determined by the inflammatory response, the mortality in the ICU and the HAIs. Cronbach's alpha value was 0.855, and VAF was 46.9%. These findings highlight the role of exposure to invasive devices in the development of HAIS in patients with acute heart disease.

Impact of adrenomedullin levels on clinical risk stratification and outcome in subarachnoid haemorrhage.

PURPOSE: To use classification tree analysis to identify risk factors for nonsurvival in a neurological patients with subarachnoid haemorrhage (SAH) and to propose a clinical model for predicting of mortality. METHODS: Prospective study of SAH admitted to a Critical Care Department and Stroke Unit over a 2-year period. Middle region of pro-ADM plasma levels (MR-proADM) was measured in EDTA plasma within the first 24 hours of hospital admission using the automatic immunofluorescence test. A regression tree was made to identify prognostic models for the development of mortality at 90 days. RESULTS: Ninety patients were included. The mean MR-proADM plasma value in the samples analysed was 0.78 ± 0.41 nmol/L. MR-proADM plasma levels were significantly associated with mortality at 90 days (1.05 ± 0.51 nmol/L vs 0.64 ± 0.25 nmol/L; P < .001). Regression tree analysis provided an algorithm based on the combined use of clinical variables and one biomarker allowing accurate mortality discrimination of three distinct subgroups with high risk of 90-day mortality ranged from 75% to 100% (AUC 0.9; 95% CI 0.83-0.98). CONCLUSIONS: The study established a model (APACHE II, MR-proADM and Hunt&Hess) to predict fatal outcomes in patients with SAH. The proposed decision-making algorithm may help identify patients with a high risk of mortality.

Molecular characterization of methicillin-resistant Staphylococcus aureus clinical strains from the endotracheal tubes of patients with nosocomial pneumonia.

BACKGROUND: Among all cases of nosocomial pneumonia, Staphylococcus aureus is the second most prevalent pathogen (17.8%). In Europe, 29.9% of the isolates are oxacillin-resistant. The changing epidemiology of methicillin-resistant Staphylococcus aureus (MRSA) nosocomial infections and the decreasing susceptibility to first-line antibiotics leave clinicians with few therapeutic options. The objective of our study was to determine the antimicrobial susceptibility, the associated molecular mechanisms of resistance and the epidemiological relatedness of MRSA strains isolated from the endotracheal tubes (ETT) of intubated critically ill patients in the intensive care unit (ICU) with nosocomial pneumonia caused by Staphylococcus aureus. METHODS: The antimicrobial susceptibility to vancomycin, linezolid, ciprofloxacin, clindamycin, erythromycin, chloramphenicol, fusidic acid, gentamicin, quinupristin-dalfopristin, rifampicin, sulfamethoxazole/trimethoprim, and tetracycline were measured. Resistance mechanisms were then analyzed by polymerase chain reaction and sequencing. Molecular epidemiology was carried out by multi-locus sequence typing. RESULTS: S. aureus isolates were resistant to ciprofloxacin, erythromycin, gentamicin, tetracycline, clindamycin, and fusidic acid. The most frequent mutations in quinolone-resistant S. aureus strains were S84L in the gyrA gene, V511A in the gyrB gene, S144P in the grlA gene, and K401R/E in the grlB gene. Strains resistant to erythromycin carried the ermC, ermA, and msrA genes; the same ermC and ermA genes were detected in strains resistant to clindamycin. The aac(6')-aph(2″) gene was related to gentamicin resistance, while resistance to tetracycline was related to tetK (efflux pump). The fusB gene was detected in the strain resistant to fusidic acid. The most frequent sequence types were ST22, ST8, and ST217, which were distributed in four clonal complexes (CC5, CC22, CC45, and CC59). CONCLUSIONS: High levels of resistance to second-line antimicrobials threatens the treatment of nosocomial respiratory infections due to methicillin-resistant S. aureus with decreased susceptibility to linezolid and vancomycin. The wide genotypic diversity found reinforces the central role of ICU infection control in preventing nosocomial transmission.

Comparative efficacy of linezolid and vancomycin for endotracheal tube MRSA biofilms from ICU patients.

PURPOSE: To compare the efficacy of systemic treatment with linezolid (LNZ) versus vancomycin (VAN) on methicillin-resistant Staphylococcus aureus (MRSA) burden and eradication in endotracheal tube (ETT) biofilm and ETT cuff from orotracheally intubated patients with MRSA respiratory infection. METHODS: Prospective observational clinical study was carried out at four European tertiary hospitals. Plasma and endotracheal aspirate (ETA) levels of LNZ and VAN were determined 72 h after treatment initiation through high-performance liquid chromatography or bioassay. LNZ or VAN concentration in the ETT biofilm and MRSA burden and eradication was determined upon extubation. The minimum inhibitory concentration (MIC) for LNZ and VAN was assessed by E-test strips (Biomerieux®). Scanning electron microscopy images were obtained, and ETT biofilm thickness was compared between groups. RESULTS: Twenty-five patients, 15 treated with LNZ and 10 with VAN, were included in the study. LNZ presented a significantly higher concentration (µg/mL) than VAN in ETT biofilm (72.8 [1.3-127.1] vs 0.4 [0.4-1.3], p < 0.001), although both drugs achieved therapeutic plasma levels 72 h after treatment initiation. Systemic treatment with LNZ achieved lower ETT cuff MRSA burdens than systemic treatment with VAN. Indeed, LNZ increased the MRSA eradication rate in ETT cuff compared with VAN (LNZ 75%, VAN 20%, p = 0.031). CONCLUSIONS: In ICU patients with MRSA respiratory infection intubated for long periods, systemic treatment with LNZ obtains a greater beneficial effect than VAN in limiting MRSA burden in ETT cuff.

Linezolid Dosing in Patients With Liver Cirrhosis: Standard Dosing Risk Toxicity.

BACKGROUND: Limited data regarding altered linezolid pharmacokinetics in patients with liver cirrhosis are available. The objective of this study was to evaluate the pharmacokinetics, efficacy and safety of linezolid in cirrhotic patients. METHODS: A case-control 1:1 study of patients undergoing linezolid therapeutic drug monitoring was conducted between January 2015 and June 2017. Cases with liver cirrhosis were matched with controls by age, body weight, comorbidities, renal function, and intensive care unit (ICU) admission. RESULTS: Fifty-two patients were included, 26 in each group. Patients with Child-Pugh Scores A, B, and C were 1 (3.8%), 13 (50.0%), and 12 (46.2%), respectively. Cases had higher median linezolid trough plasma concentrations than controls [20.6 (17.4) versus 2.7 (11.3); P < 0.001)] and more frequently achieved an optimal pharmacodynamic index [26 (100%) versus 16 (61.5%); P = 0.002]. In addition, potentially toxic concentrations and treatment discontinuation due to overexposure and hematological toxicity were also more frequently seen in cirrhotic patients. Overall clinical cure rate was high (67.4%), and in-hospital mortality was 28.8%. No differences in clinical outcomes were observed between both groups. CONCLUSIONS: Linezolid showed a high clinical cure rate. Nevertheless, plasma concentrations and treatment discontinuation due to hematological toxicity were higher in cirrhotic patients. Liver cirrhosis may influence linezolid pharmacokinetics and question the use of standard doses. Therapeutic drug monitoring of linezolid would be valuable in these patients.

Invasive fungal infection in crtically ill patients: hurdles and next challenges.

A narrative review from a multidisciplinary task force of experts in critical care medicine and clinical mycology was carried out. The multi drug-resistant species Candida auris has emerged simultaneously on several continents, causing hospital outbreaks, especially in critically ill patients. Although there are not enough data to support the routine use of continuous antibiotic prophylaxis in patients subjected to extracorporeal membrane oxygenator, a clear increase of invasive fungal infection (IFI) has been described with the use of this device. Possible IFI treatment failures could be related with suboptimal antifungal concentrations despite dose adjustment. Invasive aspergillosis has become an important life-threating infection in intensive care unit related with new risk factors described. IFI remain important problem in critical patients due to the appearance of new risk factors, new species, and resistance increase. Multidisciplinary packages of measures designed to reduce IFI incidence and improve diagnostics tools may reduce the high mortality associated.

Analyzing the impact of duration of ventilation, hospitalization, and ventilation episodes on the risk of pneumonia.

OBJECTIVE: To study the impact of duration of mechanical ventilation, hospitalization and multiple ventilation episodes on the development of pneumonia while accounting for extubation as a competing event. DESIGN: A multicenter data base from a Spanish surveillance network was used to conduct a retrospective analysis of prospectively collected intensive care patients followed from admission to discharge. SETTING: Spanish intensive care units (ICUs). PATIENTS: Mechanically ventilated adult patients from 158 ICUs with 45,486 admissions, 48,705 ventilation episodes, and 314,196 ventilator days. METHODS: Competing-risk models were applied to account for extubation plus 48 hours as a competing event for acquiring ventilator-associated pneumonia (VAP). RESULTS: Time in the ICU before mechanical ventilation was associated with an increased VAP hazard rate and with longer intubation time. This indirect prolongation of intubation increased the cumulative risk to eventually acquire VAP. For instance, comparing 3-4 versus 0 days, the adjusted VAP hazard ratio was 1.40 (95% confidence interval [CI], 1.19-1.64) and the adjusted extubation hazard ratio was 0.64 (95% CI, 0.61-0.68), which leads to an adjusted VAP subdistribution hazard ratio (sHR) of 2.13 (95% CI, 1.83-2.50). Similarly, due to prolonged intubation, multiple ventilation episodes increase the risk for VAP; the adjusted sHR is 1.52 (95% CI, 1.35-1.72) for the second episode compared to the first episode, and the adjusted sHR is 1.54 (95% CI, 1.03-2.30) for the third episode compared to the first episode. The Kaplan-Meier method produced an upward biased estimated cumulative risk for VAP. CONCLUSIONS: A competing-risk analysis is necessary to receive unbiased risk estimates and to quantify the indirect effect of intubation time on the cumulative VAP risk. Our findings may guide physicians to improve medical decisions related to the harms and benefits of the duration of ventilation.

"The multimodal approach for ventilator-associated pneumonia prevention"-requirements for nationwide implementation.

The multimodal approach for ventilator-associated pneumonia (VAP) prevention has been shown to be a successful strategy in reducing VAP rates in many intensive care units (ICU) in some countries. The simultaneous application of several measures or "bundles" to reduce VAP rates has achieved a higher impact than the progressive implementation of the individual interventions. The ultimate objective of recommendation bundles is their integration in the culture of routine healthcare of the staff in charge of ventilated patients for accomplished rates to persist over time. The noteworthy elements of this new strategy include the selection of the individual recommendations of the bundle, education of care workers (HCW) in the culture of patient safety, audit of compliance with the recommendations, commitment of the hospital management to support implementation, nomination and empowerment of local leaders of the projects in ICUs, both physicians and nurses, and the continuous collection of VAP episodes. The implementation of this new strategy is not an easy task, as both its inherent strength and important barriers to its application have become evident, which need to be overcome for maximal reduction of VAP rates.

Improving nested case-control studies to conduct a full competing-risks analysis for nosocomial infections.

OBJECTIVE: Competing risks are a necessary consideration when analyzing risk factors for nosocomial infections (NIs). In this article, we identify additional information that a competing risks analysis provides in a hospital setting. Furthermore, we improve on established methods for nested case-control designs to acquire this information. METHODS: Using data from 2 Spanish intensive care units and model simulations, we show how controls selected by time-dynamic sampling for NI can be weighted to perform risk-factor analysis for death or discharge without infection. This extension not only enables hazard rate analysis for the competing risk, it also enables prediction analysis for NI. RESULTS: The estimates acquired from the extension were in good agreement with the results from the full (real and simulated) cohort dataset. The reduced dataset results averted any false interpretation common in a competing-risks setting. CONCLUSIONS: Using additional information that is routinely collected in a hospital setting, a nested case-control design can be successfully adapted to avoid a competing risks bias. Furthermore, this adapted method can be used to reanalyze past nested case-control studies to enhance their findings.

Efficacy and safety of trimodulin, a novel polyclonal antibody preparation, in patients with severe community-acquired pneumonia: a randomized, placebo-controlled, double-blind, multicenter, phase II trial (CIGMA study).

PURPOSE: The CIGMA study investigated a novel human polyclonal antibody preparation (trimodulin) containing ~ 23% immunoglobulin (Ig) M, ~ 21% IgA, and ~ 56% IgG as add-on therapy for patients with severe community-acquired pneumonia (sCAP). METHODS: In this double-blind, phase II study (NCT01420744), 160 patients with sCAP requiring invasive mechanical ventilation were randomized (1:1) to trimodulin (42 mg IgM/kg/day) or placebo for five consecutive days. Primary endpoint was ventilator-free days (VFDs). Secondary endpoints included 28-day all-cause and pneumonia-related mortality. Safety and tolerability were monitored. Exploratory post hoc analyses were performed in subsets stratified by baseline C-reactive protein (CRP; ≥ 70 mg/L) and/or IgM (≤ 0.8 g/L). RESULTS: Overall, there was no statistically significant difference in VFDs between trimodulin (mean 11.0, median 11 [n = 81]) and placebo (mean 9.6; median 8 [n = 79]; p = 0.173). Twenty-eight-day all-cause mortality was 22.2% vs. 27.8%, respectively (p = 0.465). Time to discharge from intensive care unit and mean duration of hospitalization were comparable between groups. Adverse-event incidences were comparable. Post hoc subset analyses, which included the majority of patients (58-78%), showed significant reductions in all-cause mortality (trimodulin vs. placebo) in patients with high CRP, low IgM, and high CRP/low IgM at baseline. CONCLUSIONS: No significant differences were found in VFDs and mortality between trimodulin and placebo groups. Post hoc analyses supported improved outcome regarding mortality with trimodulin in subsets of patients with elevated CRP, reduced IgM, or both. These findings warrant further investigation. TRIAL REGISTRATION: NCT01420744.

Methodological challenges in using point-prevalence versus cohort data in risk factor analyses of nosocomial infections.

PURPOSE: To explore the impact of length-biased sampling on the evaluation of risk factors of nosocomial infections (NIs) in point-prevalence studies. METHODS: We used cohort data with full information including the exact date of the NI and mimicked an artificial 1-day prevalence study by picking a sample from this cohort study. Based on the cohort data, we studied the underlying multistate model which accounts for NI as an intermediate and discharge/death as competing events. Simple formulas are derived to display relationships between risk, hazard, and prevalence odds ratios. RESULTS: Due to length-biased sampling, long stay and thus sicker patients are more likely to be sampled. In addition, patients with NIs usually stay longer in hospital. We explored mechanisms that are-due to the design-hidden in prevalence data. In our example, we showed that prevalence odds ratios were usually less pronounced than risk odds ratios but more pronounced than hazard ratios. CONCLUSIONS: Thus, to avoid misinterpretation, knowledge of the mechanisms from the underlying multistate model is essential for the interpretation of risk factors derived from point-prevalence data.

Antibiotic selection in the treatment of acute invasive infections by Pseudomonas aeruginosa: Guidelines by the Spanish Society of Chemotherapy / Elección del tratamiento antibiótico en la infección invasiva aguda por Pseudomonas aeruginosa: Guía de la Sociedad Española de Quimioterapia

Pseudomonas aeruginosa is characterized by a notable intrinsic resistance to antibiotics, mainly mediated by the expression of inducible chromosomic β-lactamases and the production of constitutive or inducible efflux pumps. Apart from this intrinsic resistance, P. aeruginosa possess an extraordinary ability to develop resistance to nearly all available antimicrobials through selection of mutations. The progressive increase in resistance rates in P. aeruginosa has led to the emergence of strains which, based on their degree of resistance to common antibiotics, have been defined as multidrug resistant, extended-resistant and panresistant strains. These strains are increasingly disseminated worldwide, progressively complicating the treatment of P. aeruginosa infections. In this scenario, the objective of the present guidelines was to review and update published evidence for the treatment of patients with acute, invasive and severe infections caused by P. aeruginosa. To this end, mechanisms of intrinsic resistance, factors favoring development of resistance during antibiotic exposure, prevalence of resistance in Spain, classical and recently appeared new antibiotics active against P. aeruginosa, pharmacodynamic principles predicting efficacy, clinical experience with monotherapy and combination therapy, and principles for antibiotic treatment were reviewed to elaborate recommendations by the panel of experts for empirical and directed treatment of P. aeruginosa invasive infections (AU)

Pseudomonas aeruginosa se caracteriza por una notable resistencia intrínseca a los antibióticos mediada fundamentalmente por la expresión de β-lactamasas cromosómicas inducibles y la producción constitutiva o inducible de bombas de expulsión. Además de esta resistencia intrínseca, P. aeruginosa posee una extraordinaria capacidad para desarrollar resistencia a prácticamente todos los antimicrobianos disponibles a través de la selección de mutaciones. El aumento progresivo de la resistencia en P. aeruginosa ha llevado a la aparición de cepas que, de acuerdo con el grado de resistencia frente a los antibióticos habituales, se han definido como multirresistentes, extensamente resistentes y panresistentes. Estas cepas se están diseminando mundialmente, complicando progresivamente el tratamiento de las infecciones por P. aeruginosa. En este escenario, el objetivo de las presentes recomendaciones es la revisión y puesta al día de la evidencia publicada para el tratamiento de pacientes con infección aguda, invasiva y grave por P. aeruginosa. Con este fin, se han revisado los mecanismos de resistencia intrínseca, factores que favorecen el desarrollo de resistencia durante la exposición a antibióticos, prevalencia de la resistencia en España, antibióticos clásicos así como los de reciente introducción activos frente a P. aeruginosa, principios farmacodinámicos predictores de eficacia, experiencia clínica con tratamientos en monoterapia o terapia combinada y principios del tratamiento antibiótico para elaborar por un panel de xpertos recomendaciones para el tratamiento empírico o dirigido de infecciones invasivas por P. aeruginosa (AU)

A Before-and-After Study of the Effectiveness of an Antimicrobial Stewardship Program in Critical Care.

We evaluated the use of antimicrobials expressed as defined daily doses (DDDs) per 1,000 patient days and days of therapy (DOT) per 100 occupied bed-days in a intensive care unit (ICU) of a general hospital in Barcelona, Spain, before and after implementation of an antimicrobial stewardship (AMS) program (2007 to 2010 versus 2011 to 2015). The quarterly costs of antimicrobials used in the ICU and its weight in the overall hospital costs of antimicrobials were calculated. The effect of the applied AMS program on DDDs and DOT time series data was analyzed by means of intervention time series analysis. A total of 5,002 patients were included (1,971 for the first [before] period and 3,031 for the second [after] period). The percentage of patients treated with one or more antimicrobials decreased from 88.6 to 77.2% (P < 0.001). DDDs decreased from 246.8 to 192.3 (mean difference, -54.5; P = 0.001) and DOT from 66.7 to 54.6 (mean difference, -12.1; P = 0.066). The mean cost per trimester decreased from €115,543 to €73,477 (mean difference, -42,065.4 euros; P < 0.001), and the percentage of ICU antimicrobials cost with respect to the total cost of hospital antimicrobials decreased from 28.5 to 22.8% (mean difference, -5.59; P = 0.023). Implementation of an AMS program in the ICU was associated with a marked reduction in the use of antimicrobials, with cost savings close to one million euros since its implementation. An AMS program can have a significant impact on optimizing antimicrobial use in critical care practice.

Prevention of Ventilator-Associated Pneumonia: The Multimodal Approach of the Spanish ICU "Pneumonia Zero" Program.

OBJECTIVES: The "Pneumonia Zero" project is a nationwide multimodal intervention based on the simultaneous implementation of a comprehensive evidence-based bundle measures to prevent ventilator-associated pneumonia in critically ill patients admitted to the ICU. DESIGN: Prospective, interventional, and multicenter study. SETTING: A total of 181 ICUs throughout Spain. PATIENTS: All patients admitted for more than 24 hours to the participating ICUs between April 1, 2011, and December 31, 2012. INTERVENTION: Ten ventilator-associated pneumonia prevention measures were implemented (seven were mandatory and three highly recommended). The database of the National ICU-Acquired Infections Surveillance Study (Estudio Nacional de Vigilancia de Infecciones Nosocomiales [ENVIN]) was used for data collection. Ventilator-associated pneumonia rate was expressed as incidence density per 1,000 ventilator days. Ventilator-associated pneumonia rates from the incorporation of the ICUs to the project, every 3 months, were compared with data of the ENVIN registry (April-June 2010) as the baseline period. Ventilator-associated pneumonia rates were adjusted by characteristics of the hospital, including size, type (public or private), and teaching (postgraduate) or university-affiliated (undergraduate) status. MEASUREMENTS AND MAIN RESULTS: The 181 participating ICUs accounted for 75% of all ICUs in Spain. In a total of 171,237 ICU admissions, an artificial airway was present on 505,802 days (50.0% of days of stay in the ICU). A total of 3,474 ventilator-associated pneumonia episodes were diagnosed in 3,186 patients. The adjusted ventilator-associated pneumonia incidence density rate decreased from 9.83 (95% CI, 8.42-11.48) per 1,000 ventilator days in the baseline period to 4.34 (95% CI, 3.22-5.84) after 19-21 months of participation. CONCLUSIONS: Implementation of the bundle measures included in the "Pneumonia Zero" project resulted in a significant reduction of more than 50% of the incidence of ventilator-associated pneumonia in Spanish ICUs. This reduction was sustained 21 months after implementation.

Intensive care unit patients with lower respiratory tract nosocomial infections: the ENIRRIs project.

The clinical course of intensive care unit (ICU) patients may be complicated by a large spectrum of lower respiratory tract infections (LRTI), defined by specific epidemiological, clinical and microbiological aspects. A European network for ICU-related respiratory infections (ENIRRIs), supported by the European Respiratory Society, has been recently established, with the aim at studying all respiratory tract infective episodes except community-acquired ones. A multicentre, observational study is in progress, enrolling more than 1000 patients fulfilling the clinical, biochemical and radiological findings consistent with a LRTI. This article describes the methodology of this study. A specific interest is the clinical impact of non-ICU-acquired nosocomial pneumonia requiring ICU admission, non-ventilator-associated LRTIs occurring in the ICU, and ventilator-associated tracheobronchitis. The clinical meaning of microbiologically negative infectious episodes and specific details on antibiotic administration modalities, dosages and duration are also highlighted. Recently released guidelines address many unresolved questions which might be answered by such large-scale observational investigations. In light of the paucity of data regarding such topics, new interesting information is expected to be obtained from our network research activities, contributing to optimisation of care for critically ill patients in the ICU.

Ceftolozane-tazobactam for the treatment of ventilator-associated infections by colistin-resistant Pseudomonas aeruginosa / Ceftolozano-tazobactam en el tratamiento de infecciones respiratorias asociadas a ventilación mecánica por Pseudomonas aeruginosa resistente a colistina

The use of colistin for the treatment of multiresistant bacteria has led to the emergence of colistin-resistant strains of Gram-negative bacilli. Treatment of infections caused by these pan-drug-resistant bacteria is difficult owing to the paucity of effective antibiotics. We report two cases of ventilator-associated respiratory infection caused by pan-drug-resistant, colistin-resistant Pseudomonas aeruginosa that were successfully treated with ceftolozane-tazobactam (AU)

La utilización de colistina para el tratamiento de bacterias multirresistentes ha favorecido la aparición de cepas de bacilos gramnegativos resistentes a dicho antibiótico. El tratamiento de las infecciones producidas por estas bacterias panresistentes es difícil dada la escasez de antibióticos que se pueden emplear en esta situación. Se presentan dos pacientes con infecciones respiratorias relacionadas con ventilación mecánica producidas por una Pseudomonas aeruginosa panresistente y resistente a colistina que fueron tratadas con ceftolozano/tazobactam con buenos resultados (AU)