Descontaminación selectiva del tubo digestivo: efecto sobre la incidencia de la infección nosocomial y de los microorganismos multirresistentes en enfermos ingresados en unidades de cuidados intensivos

Colonization With Extensively Drug-Resistant Acinetobacter baumannii and Prognosis in Critically Ill Patients: An Observational Cohort Study

Background: Acinetobacter baumannii is one of the most frequently isolated opportunistic pathogens in intensive care units (ICUs). Extensively drug-resistant A. baumannii (XDR-AB) strains lack susceptibility to almost all antibiotics and pose a heavy burden on healthcare institutions. In this study, we evaluated the impact of XDR-AB colonization on both the short-term and long-term survival of critically ill patients. Methods: We prospectively enrolled patients from two adult ICUs in Qilu Hospital of Shandong University from March 2018 through December 2018. Using nasopharyngeal and perirectal swabs, we evaluated the presence of XDR-AB colonization. Participants were followed up for 6 months. The primary endpoints were 28-day and 6-month mortality after ICU admission. The overall survival rate was estimated by the Kaplan-Meier method. We identified risk factors associated with 28-day and 6-month mortality using the logistic regression model and a time-dependent Cox regression model, respectively. Results: Out of 431 patients, 77 were colonized with XDR-AB. Based on the Kaplan-Meier curve results, the overall survival before 28 days did not differ by colonization status; however, a significantly lower overall survival rate was obtained at 6 months in colonized patients. Univariate and multivariate analysis results confirmed that XDR-AB colonization was not associated with 28-day mortality, but was an independent risk factor of lower overall survival at 6 months (HR = 1.749, 95% CI = 1.174-2.608). Conclusions: XDR-AB colonization has no effect on short-term overall survival, but is associated with lower long-term overall survival in critically ill patients.

Selective decontamination of the digestive tract reduces pneumonia and mortality

Selective decontamination of the digestive tract (SDD) has been subject of numerous randomized controlled trials in critically ill patients. Almost all clinical trials showed SDD to prevent pneumonia. Nevertheless, SDD has remained a controversial strategy. One reason for why clinicians remained reluctant to implement SDD into daily practice could be that mortality was reduced in only 2 trials. Another reason could be the heterogeneity of trials of SDD. Indeed, many different prophylactic antimicrobial regimes were tested, and dissimilar diagnostic criteria for pneumonia were applied amongst the trials. This heterogeneity impeded interpretation and comparison of trial results. Two other hampering factors for implementation of SDD have been concerns over the risk of antimicrobial resistance and fear for escalation of costs associated with the use of prophylactic antimicrobials. This paper describes the concept of SDD, summarizes the results of published trials of SDD in mixed medical-surgical intensive care units, and rationalizes the risk of antimicrobial resistance and rise of costs associated with this potentially life-saving preventive strategy.

[Selective decontamination of the digestive tract: repercussions on microbiology laboratory workload and costs, and antibiotic resistance trends]

INTRODUCTION

This study determines the workload and cost of implementing selective digestive decontamination in the microbiology laboratory, and reports the impact on microbial flora and bacterial resistance trends in the intensive care unit (ICU).

METHODS

The total microbiological workload and cost were quantified, as well as the part charged to the petitioning service, in the year before and the year after introducing the procedure. Changes in microbial flora were evaluated and bacterial resistance trends were analyzed over 12 years in 21 sentinel antimicrobial/microorganism combinations.

RESULTS

The workload ascribed to the ICU increased by 10% and cost increased by 1.8% in the period after introduction of the procedure (non-significant differences). The increased workload resulting from epidemiological surveillance cultures was compensated by significant reductions in quantitative endotracheal aspirate cultures, blood cultures, exudate cultures, identification tests with antibiograms, and serologies. The procedure has been associated with a significant decrease in Acinetobacter isolates and a significant increase in Enterococcus. Three significant trends of increased resistance were detected, all of them in Pseudomonas aeruginosa (imipenem, tobramycin, and ciprofloxacin).

CONCLUSIONS

In our hospital, implementation of selective digestive decontamination did not cause a significant increase in the workload or costs in the microbiology laboratory. Selective digestive decontamination was associated with a significant decrease in Acinetobacter, an increase in Enterococcus, and higher resistance to imipenem, tobramycin and ciprofloxacin in P. aeruginosa.

[Comparative study of three selective methods for nosocomial pneumonia surveillance in non-critical adult patients]

BACKGROUND AND OBJECTIVE

Among nosocomial infections, pneumonia is one of the most important ones due to the mortality, morbidity and the increase of costs that it causes. The implementation of a cost-effective surveillance system for these infections is a challenge for hospitals. The objective of this work was to evaluate three selective methods of surveillance for nosocomial pneumonias in non-critical adult patients.

PATIENTS AND METHOD

A prospective surveillance of nosocomial pneumonias was carried out during 4 months in an university hospital of the Valencian Community, by means of three methods based on reports of chest x-ray, consumption of several antibiotics and health-care workers' liaison. Subsequently, possible cases were confirmed through revision of patient's charts, comparing each method with the reference one.

RESULTS

Of 541 possible cases of pneumonia, 27 were confirmed. The cumulative incidence was 3.67 cases/1,000 admissions and the incidence density was 5.9 cases/10,000 patient-days. The method with the highest sensitivity was that dealing with the consumption of antibiotics (85.2%), followed by x-rays (70.4%). The method based on the personnel's liaison had 99.4% specificity, while that of x-rays was 75.5%. Negative predictive values were above 95% for the three methods.

CONCLUSIONS

A surveillance system for nosocomial pneumonia based on reports of chest x-rays may be very efficient, providing the necessary information to program and to evaluate the prevention and control activities for these infections in the hospital.