Ecological effects of selective oral decontamination on multidrug-resistance bacteria acquired in the intensive care unit: a case-control study over 5 years

Does selective digestive decontamination (SDD) increase antibiotic resistance? Long-term comparison of two intensive care units (with and without SDD) of the same tertiary hospital

PURPOSE

The aim of this study was to to compare the antimicrobial resistance rate and its relationship with the antibiotic consumption in two separate Intensive Care Units (ICUs) of the same hospital, one with and other without selective decontamination of the digestive tract (SDD).

METHODS

We performed a retrospective study in the two ICUs of the Araba University Hospital. Trauma and neurosurgical patients are admitted to the SDD-ICU, and general digestive surgery patients go to the no SDD-ICU. From 2014 to 2018 we analyzed the number of isolates, and the bacterial resistance trends of 47 antimicrobial-microorganism combinations. Additionally, antimicrobial consumption was estimated in both ICUs. Resistance rates were also compared with those reported in ENVIN-HELICS Spanish national registry.

RESULTS

In the ICU with SDD protocol, there was a significant decrease in the resistance of E. coli to amoxicillin/clavulanic acid and in the resistance of E. faecalis to high concentration of gentamycin and high concentration of streptomycin. A significant increase of resistance of Staphylococcus coagulasa negative (CoNS) to linezolid in the no SDD-ICU was also detected. Overall, the level of resistance in the SDD-ICU was lower or of the same order than in the ICU without SDD and that reported in the Spanish national registry.

CONCLUSIONS

SDD had neither a clinically relevant impact on emergence and spread of resistance, nor in the overall systemic antimicrobial use. The patient type rather than the SDD protocol showed to condition the ecology and therefore, the resistance rate in the ICUs.

Surveillance and prevention of healthcare-associated infections: best practices to prevent ventilator-associated events

INTRODUCTION

Ventilator associated pneumonia (VAP) leads to an increase in morbidity, mortality, and healthcare costs. In addition to increased evidence from the latest European and American guidelines (published in 2017 and 2022, respectively), in the last two years, several important clinical experiences have added new prevention tools to be included to improve the management of VAP.

AREAS COVERED

This paper is a narrative review of new evidence on VAP prevention. We divided VAP prevention measures into pharmacological, non-pharmacological, and ventilator care bundles.

EXPERT OPINION

Most of the effective strategies that have been shown to decrease the incidence of complications are easy to implement and inexpensive. The implementation of care bundles, accompanied by educational measures and a multidisciplinary team should be part of optimal management. In addition to ventilator care bundles for the prevention of VAP, it could possibly be beneficial to use ventilator care bundles for the prevention of noninfectious ventilator associated events.

ICU-acquired infections in immunocompromised patients

Immunocompromised patients account for an increasing proportion of the typical intensive care unit (ICU) case-mix. Because of the increased availability of new drugs for cancer and auto-immune diseases, and improvement in the care of the most severely immunocompromised ICU patients (including those with hematologic malignancies), critically ill immunocompromised patients form a highly heterogeneous patient population. Furthermore, a large number of ICU patients with no apparent immunosuppression also harbor underlying conditions altering their immune response, or develop ICU-acquired immune deficiencies as a result of sepsis, trauma or major surgery. While infections are associated with significant morbidity and mortality in immunocompromised critically ill patients, little specific data are available on the incidence, microbiology, management and outcomes of ICU-acquired infections in this population. As a result, immunocompromised patients are usually excluded from trials and guidelines on the management of ICU-acquired infections. The most common ICU-acquired infections in immunocompromised patients are ventilator-associated lower respiratory tract infections (which include ventilator-associated pneumonia and tracheobronchitis) and bloodstream infections. Recently, several large observational studies have shed light on some of the epidemiological specificities of these infections-as well as on the dynamics of colonization and infection with multidrug-resistant bacteria-in these patients, and these will be discussed in this review. Immunocompromised patients are also at higher risk than non-immunocompromised hosts of fungal and viral infections, and the diagnostic and therapeutic management of these infections will be covered. Finally, we will suggest some important areas of future investigation.

Gut Microbiome in Sepsis

Abstract The gut has been hypothesized to be the "motor" of multiple organ dysfunction in sepsis. Although there are multiple ways in which the gut can drive systemic inflammation, increasing evidence suggests that the intestinal microbiome plays a more substantial role than previously appreciated. An English language literature review was performed to summarize the current knowledge of sepsis-induced gut microbiome dysbiosis. Conversion of a normal microbiome to a pathobiome in the setting of sepsis is associated with worsened mortality. Changes in microbiome composition and diversity signal the intestinal epithelium and immune system resulting in increased intestinal permeability and a dysregulated immune response to sepsis. Clinical approaches to return to microbiome homeostasis may be theoretically possible through a variety of methods including probiotics, prebiotics, fecal microbial transplant, and selective decontamination of the digestive tract. However, more research is required to determine the efficacy (if any) of targeting the microbiome for therapeutic gain. The gut microbiome rapidly loses diversity with emergence of virulent bacteria in sepsis. Restoring normal commensal bacterial diversity through various therapies may be an avenue to improve sepsis mortality.

Role of Selective Digestive Decontamination in the Prevention of Ventilator-Associated Pneumonia in COVID-19 Patients: A Pre-Post Observational Study

The aim of our study was to evaluate whether the introduction of SDD in a structured protocol for VAP prevention was effective in reducing the occurrence of ventilator-associated pneumonia (VAP) in COVID-19 patients without changes in the microbiological pattern of antibiotic resistance. This observational pre-post study included adult patients requiring invasive mechanical ventilation (IMV) for severe respiratory failure related to SARS-CoV-2 admitted in three COVID-19 intensive care units (ICUs) in an Italian hospital from 22 February 2020 to 8 March 2022. Selective digestive decontamination (SDD) was introduced from the end of April 2021 in the structured protocol for VAP prevention. The SDD consisted of a tobramycin sulfate, colistin sulfate, and amphotericin B suspension applied in the patient's oropharynx and the stomach via a nasogastric tube. Three-hundred-and-forty-eight patients were included in the study. In the 86 patients (32.9%) who received SDD, the occurrence of VAP decreased by 7.7% (p = 0.192) compared to the patients who did not receive SDD. The onset time of VAP, the occurrence of multidrug-resistant microorganisms AP, the length of invasive mechanical ventilation, and hospital mortality were similar in the patients who received and who did not receive SDD. The multivariate analysis adjusted for confounders showed that the use of SDD reduces the occurrence of VAP (HR 0.536, CI 0.338-0.851; p = 0.017). Our pre-post observational study indicates that the use of SDD in a structured protocol for VAP prevention seems to reduce the occurrence of VAP without changes in the incidence of multidrug-resistant bacteria in COVID-19 patients.