Selective Digestive Decontamination Research Articles

Proof‑of‑concept study to quantify changes in intestinal loads of KPC-producing Klebsiella pneumoniae in colonised patients following selective digestive decontamination with oral gentamicin

To monitor quantitatively the extent of intestinal colonisation by KPC-producing Klebsiella pneumoniae (KPC-Kp) in colonised patients who receive selective digestive decontamination (SDD) with oral gentamicin. We developed a real-time quantitative PCR(qPCR) method for determination of the relative load of blaKPC (RLKPC) within the gut microbiota. Clinical validation was performed using a culture method as the gold standard and receiver operating curve (ROC) analysis. Fifteen patients were observationally and prospectively followed for one year. Clinical, microbiological variables and rectal swab samples were collected at 0 (baseline), 14 and 30 days and monthly thereafter. Clinical validation performed on 111 rectal swab samples demonstrated that the PCR method detected 17% more positives than theculture method. ROC curve analysis documented excellent agreement between both methods (area under the curve, 0.96; 95% confidence interval 0.93-0.99). The RLKPC decreased in 6/15 (40%) and 7/12 (58.3%) patients on days 14 and 30, respectively. Persistent eradication was observed in 2/12 (16.7%), 3/9 (33.3%), 4/8 (50%) and 7/8 (87.5%) patients at 1, 3, 6 and 12 months, respectively, with a median time of 150 days (range 30-270) to persistent eradication. Gentamicin-resistant KPC-Kp isolates were identified in 4/15 (26.7%) patients. The rates of infections (57.1% vs. 12.5%, P=0.119) and deaths (71.4% vs. 0%, P=0.007) were higher among patients with high baseline RLKPC. Following SDD, a rapid reduction on intestinal load is observed when the colonising KPC-Kp isolate is susceptible to gentamicin; however, persistent eradication at the end of SDD is low. Intestinal carriage of KPC-Kp persists after three months in about one third of patients.

Absence of candidemia in critically ill patients with COVID-19 receiving selective digestive decontamination

Absence of candidemia in critically ill patients with COVID-19 receiving selective digestive decontamination

Role of the environment in transmission of Gram-negative bacteria in two consecutive outbreaks in a haematology-oncology department

SummaryIn 2019–2020, two subsequent outbreaks caused by phenotypically identical ESBL-producing Enterobacter cloacae and multi-drug-resistant (MDR) Pseudomonas putida were detected in respectively 15 and 9 patients of the haematology-oncology department. Both bacterial species were resistant to piperacillin-tazobactam, used empirically in (neutropenic) sepsis in our hospital, and ciprofloxacin, used prophylactically in selective digestive decontamination for haematology patients. The E. cloacae outbreak was identified in clinical cultures of blood and urine. Despite intensified infection control measures, new cases were found in weekly point-prevalence screening cultures. Environmental samples of sinks and shower drains appeared positive in 18.1%. To diminish the environmental contamination burden, all siphons of sinks were replaced, and disinfection of sinks and shower drains was intensified using chlorine and soda on a daily basis. Replacement of shower drains was not possible. The outbreak of P. putida remained limited to rectal cultures only, and disappeared spontaneously without interventions. During both outbreaks, multiple strains of the incriminated bacterium were found simultaneously (demonstrated by Amplified-Fragment Length Polymorphism and/or Whole-Genome Multi-locus Sequencing Typing) in patients as well as the environment. It was experimentally shown that a biofilm on the toilet edge may act as a source for nosocomial transmission of Gram-negative bacteria. In conclusion, the drainage system of the hospital is an important reservoir of MDR bacteria, threatening the admitted patients. In existing hospitals, biofilms in the drainage systems cannot be removed. Therefore, it is important that in (re)building plans for hospitals a plan for prevention of nosocomial transmission from environment to patients is incorporated.

Enteral Vancomycin to Eliminate MRSA Carriership of the Digestive Tract in Critically Ill Patients.

Background: Carriership with methicillin resistant Staphylococcus aureus (MRSA) is a risk for the development of secondary infections in critically ill patients. Previous studies suggest that enteral vancomycin is able to eliminate enteral carriership with MRSA. Data on individual effects of this treatment are lacking. Methods: Retrospective analysis of a database containing 15 year data of consecutive patients from a mixed medical-(cardio)surgical 18 bedded intensive care unit was conducted. All consecutive critically ill patients with enteral MRSA carriership detected in throat and/or rectal samples were collected. We analyzed those with follow-up cultures to determine the success rate of enteral vancomycin. Topical application of 2% vancomycin in a sticky oral paste was performed combined with a vancomycin solution of 500 mg four times daily in the nasogastric tube. This treatment was added to a regimen of selective digestive tract decontamination (SDD) to prevent ICU acquired infection. Results: Thirteen patients were included. The mean age was 65 years and the median APACHE II score was 21. MRSA was present in the throat in 8 patients and in both throat and rectum in 5 patients. In all patients MRSA was successfully eliminated from both throat and rectum, which took 2–11 days with a median duration until decontamination of 4 days. Secondary infections with MRSA did not occur. Conclusions: Topical treatment with vancomycin in a 2% sticky oral paste four times daily in the nasogastric tube was effective in all patients in the elimination of MRSA and prevented secondary MRSA infections.

Structural equation modelling the relationship between anti-fungal prophylaxis and Pseudomonas bacteremia in ICU patients

PurposeAnimal models implicate candida colonization facilitating invasive bacterial infections. The clinical relevance of this microbial interaction remains undefined and difficult to study directly. Observations from studies of anti-septic, antibiotic, anti-fungal, and non-decontamination-based interventions to prevent ICU acquired infection collectively serve as a natural experiment.MethodsThree candidate generalized structural equation models (GSEM), with Candida and Pseudomonas colonization as latent variables, were confronted with blood culture and respiratory tract isolate data derived from 464 groups from 279 studies including studies of combined antibiotic and antifungal exposures within selective digestive decontamination (SDD) interventions.ResultsIntroducing an interaction term between Candida colonization and Pseudomonas colonization substantially improved GSEM model fit. Model derived coefficients for singular exposure to anti-septic agents (− 1.23; − 2.1 to − 0.32), amphotericin (− 1.78; − 2.79 to − 0.78) and topical antibiotic prophylaxis (TAP; + 1.02; + 0.11 to + 1.93) versus Candida colonization were similar in magnitude but contrary in direction. By contrast, the model-derived coefficients for singular exposure to TAP, as with anti-septic agents, versus Pseudomonas colonization were weaker or non-significant. Singular exposure to amphotericin would be predicted to more than halve candidemia and Pseudomonas bacteremia incidences versus literature benchmarks for absolute differences of approximately one percentage point or less.ConclusionGSEM modelling of published data supports the postulated interaction between Candida and Pseudomonas colonization towards promoting bacteremia among ICU patients. This would be difficult to detect without GSEM modelling. The model indicates that anti-fungal agents have greater impact in preventing Pseudomonas bacteremia than TAP, which has no impact.

772. Effect of Selective Digestive Decontamination Using Oral Colistin on HAI Rates and All-Cause Mortality Among Cardiovascular Surgery Patients - A Single Centre Experience from India

BackgroundHospital acquired infections affect the morbidity and mortality of ICU patients considerably. Selective digestive decontamination (SDD) is defined as the prophylactic application of topical, non-absorbable antimicrobials in the oropharynx and stomach, with the goal of eradicating potentially pathogenic microorganisms but preserving the protective anaerobic microbiota. SDD has been applied in trials among critically ill patients and found to be effective in reducing HAI. MethodsThis cohort study was conducted in our cardiothoracic vascular surgery ICU of a tertiary care hospital, where patients were given oral colistin syrup (100mg 6th hourly for 5 days) in the immediate post op during the intervention period. We compared the clinical and microbiological outcomes of patients before (5 months, pre-intervention arm) and after (5 months, intervention arm) the implementation of SDD (Oral colistin syrup).ResultsA total of 78 patients were included in the interventional arm with a mean age of 58.7 years whereas the pre-interventional group consisted of 94 study participants with a median age of 57.5 years. 11 out of 94 had positive respiratory sample culture (11.7%) in the preintervention group which mandated antibiotic therapy for HAP compared to one culture positive in the interventional period (OR 0.0980, 95% CI: 0.0124 to 0.777 and P=0.0279). One patient had blood stream infection in the pre-intervention period compared to none in the intervention phase. All-cause mortality in the pre-interventional group was 7.44% (7 in 94) vs 1.28% (1 in 78) in the interventional group (OR 0.1614, 95% CI: 0.0194 to 1.3416, P= 0.0914). Adverse events (nausea, vomiting & loose stools) were observed in a total of 24 study patients, but necessitated withdrawal of regimen only in nine patients.ConclusionAn SDD regimen of Colistin alone in Cardiac Surgery patients resulted in statistically significant reduction in incidence of Hospital Acquired Pneumonia, along with a reduction in all-cause mortality (though not statistically significant). Disclosures All Authors: No reported disclosures

Modelling and Simulation of the Effect of Targeted Decolonisation on Incidence of Extended-Spectrum Beta-Lactamase-Producing Enterobacterales Bloodstream Infections in Haematological Patients.

IntroductionHaematological patients are at higher risk of bloodstream infections (BSI) after chemotherapy. The aim of this study was to develop a simulation model assessing the impact of selective digestive decontamination (SDD) of haematological patients colonised with extended-spectrum beta-lactamase-producing Enterobacterales (ESBL-E) on the incidence of ESBL-E BSI after chemotherapy.MethodsA patient population was created by a stochastic simulation model mimicking the patients’ states of colonisation with ESBL-E during hospitalisation. A systematic literature search was performed to inform the model. All ESBL-E carriers were randomised (1:1) to either the intervention (targeted SDD) or the control group (placebo). ESBL-E BSI incidence was the outcome of the model. Sensitivity analyses were performed by prevalence of ESBL-E carriage at hospital admission (low: < 10%, medium: 10–25%, high: > 25%), duration of neutropenia after receiving chemotherapy, administration of antibiotic prophylaxis with quinolones, and time interval between SDD and chemotherapy.ResultsThe model estimated that the administration of targeted SDD before chemotherapy reduces the incidence of ESBL-E BSI in the hospitalised haematological population up to 27%. The greatest benefit was estimated in high-prevalence settings, regardless of the duration of neutropenia, the time interval before chemotherapy, and the administration of antibiotic prophylaxis with quinolones (p < 0.05). In medium-prevalence settings, SDD was effective in patients receiving quinolone prophylaxis, with either 1-day time interval before chemotherapy and a neutropenia duration > 6 days (p < 0.05) or 7-day time interval before chemotherapy and a neutropenia duration > 9 days (p < 0.05). No benefit was observed in low-prevalence settings.ConclusionsOur model suggests that targeted SDD could decrease the rate of ESBL-E BSI in haematological carriers before chemotherapy in the setting of high ESBL-E prevalence at hospital admission. These estimates require confirmation by well-designed multicentre RCTs, including the assessment of the impact on resistance/disruption patterns of gut microbiome.Supplementary InformationThe online version contains supplementary material available at 10.1007/s40121-021-00550-3.

Oropharyngeal Decontamination for Prevention of VAP in Patients Admitted to Intensive Care Units: A Systematic Review.

Introduction: Oropharyngeal colonization with pathogenic organisms contributes to the development of ventilator-associated pneumonia (VAP) in intensive care units (ICUs). Oral hygiene care (OHC) is a very effective method for reducing the risk of VAP in these patients. This study aimed to evaluate recent OHC strategies to decrease VAP. Methods: Randomized clinical trials (RCTs) published in the PubMed, Scopus, Embase, Cochrane Library, and Web of Science databases from inception to September 10, 2020 were reviewed to compare the effects of selective oropharyngeal decontamination (SOD) on the incidence of VAP in adult patients requiring mechanical ventilation. Results: Out of a total of 1098 articles reviewed, 17 eligible studies were included for final analysis. The results showed that the use of chlorhexidine for oropharyngeal decontamination reduces the incidence of VAP. However, it had a small effect on gram-negative resistant bacteria. Also, it was observed that the combined use of colistin and chlorhexidine was more effective than chlorhexidine alone in preventing VAP. The results of studies on the use of toothbrushes to reduce the incidence of pneumonia are unclear since they used chlorhexidine at the same time. However, tooth brushing is one of the best ways to maintain oral hygiene. Using povidoneiodine, Nanosil, and non-absorbable topical antibiotics reduced the incidence of VAP, while Iseganan did not show a significant effect in this regard. Conclusion: The prophylactic use of topical bactericidal agents in critically-ill patients is effective in reducing the incidence of VAP. However, the use of non-absorbable topical antibiotics is more effective than other methods in oropharyngeal decontamination.

Extended Lung Ultrasound to Differentiate Between Pneumonia and Atelectasis in Critically Ill Patients: A Diagnostic Accuracy Study.

To determine the diagnostic accuracy of extended lung ultrasonographic assessment, including evaluation of dynamic air bronchograms and color Doppler imaging to differentiate pneumonia and atelectasis in patients with consolidation on chest radiograph. Compare this approach to the Simplified Clinical Pulmonary Infection Score, Lung Ultrasound Clinical Pulmonary Infection Score, and the Bedside Lung Ultrasound in Emergency protocol. Prospective diagnostic accuracy study. Adult ICU applying selective digestive decontamination. Adult patients that underwent a chest radiograph for any indication at any time during admission. Patients with acute respiratory distress syndrome, coronavirus disease 2019, severe thoracic trauma, and infectious isolation measures were excluded. None. Lung ultrasound was performed within 24 hours of chest radiograph. Consolidated tissue was assessed for presence of dynamic air bronchograms and with color Doppler imaging for presence of flow. Clinical data were recorded after ultrasonographic assessment. The primary outcome was diagnostic accuracy of dynamic air bronchogram and color Doppler imaging alone and within a decision tree to differentiate pneumonia from atelectasis. Of 120 patients included, 51 (42.5%) were diagnosed with pneumonia. The dynamic air bronchogram had a 45% (95% CI, 31-60%) sensitivity and 99% (95% CI, 92-100%) specificity. Color Doppler imaging had a 90% (95% CI, 79-97%) sensitivity and 68% (95% CI, 56-79%) specificity. The combined decision tree had an 86% (95% CI, 74-94%) sensitivity and an 86% (95% CI, 75-93%) specificity. The Bedside Lung Ultrasound in Emergency protocol had a 100% (95% CI, 93-100%) sensitivity and 0% (95% CI, 0-5%) specificity, while the Simplified Clinical Pulmonary Infection Score and Lung Ultrasound Clinical Pulmonary Infection Score had a 41% (95% CI, 28-56%) sensitivity, 84% (95% CI, 73-92%) specificity and 68% (95% CI, 54-81%) sensitivity, 81% (95% CI, 70-90%) specificity, respectively. In critically ill patients with pulmonary consolidation on chest radiograph, an extended lung ultrasound protocol is an accurate and directly bedside available tool to differentiate pneumonia from atelectasis. It outperforms standard lung ultrasound and clinical scores.

Selective digestive decontamination, a seemingly effective regimen with individual benefit or a flawed concept with population harm?

Selective digestive decontamination (SDD) regimens, variously constituted with topical antibiotic prophylaxis (TAP) and protocolized parenteral antibiotic prophylaxis (PPAP), appear highly effective for preventing ICU-acquired infections but only within randomized concurrent control trials (RCCT’s). Confusingly, SDD is also a concept which, if true, implies population benefit. The SDD concept can finally be reified in humans using the broad accumulated evidence base, including studies of TAP and PPAP that used non-concurrent controls (NCC), as a natural experiment. However, this test implicates overall population harm with higher event rates associated with SDD use within the ICU context.

A Simple Bundle to Control an Outbreak of Carbapenem-Resistant Enterobacteriacae in an Onco-Hematological Inpatient Unit: Report from a Single Center

INTRODUCTIONCarbapenem-Resistant Enterobacteriaceae (CRE) are an emerging global healthcare problem given their rising incidence and the elevated morbidity and mortality associated with bloodstream infections (BSI) due to these pathogens. Patients with hematological malignancies are at higher risk of complications, as they frequently require prolonged hospitalization and develop severe neutropenia and mucositis, becoming severely immunocompromised. Therefore, mortality rates of CRE bacteremia in these patients are as high as 60%. Despite their severity and growing incidence, few strategies have been described to effectively control the spread of CREs, particularly in the high-risk and endemic settings. Here we describe an effective and feasible intervention to control an outbreak of CREs in an onco-hematological inpatient unit. METHODSOur onco-hematological inpatient unit is set in a hospital with 350 beds in southeast Brazil. It has 9 beds in double-occupancy rooms with a volume of about 180 patients a year, mainly with acute leukemia and other hematological malignancies. Prior to the outbreak, interventions for the control of CRE spread consisted of: 1) contact precautions in single-bed rooms for CRE carriers and 2) strict room and hand-hygiene measures. Interventions for the CRE outbreak consisted of: 1) use of single-bed rooms for patients with acute leukemia or other hematological diseases with severe and prolonged neutropenia, irrespective of their CRE status; 2) weekly rectal swabs for CRE carrier status assessment; 3) reinforcement of strict room and hand hygiene practices; 4) nursing staff cohorting according to CRE status and for patients with and without acute leukemia; 5) selective digestive tract decontamination (SDD) with gentamycin 60 mg qid and antimicrobial prophylaxis with amoxicillin 500 mg tid. RESULTSThe first case of CRE colonization in our unit was diagnosed in 2013. CRE spread had a stable incidence from 2013 to 2016, with 4.0-5.0 new CRE-carriers (either colonization or BSI)/1000 patients-day. Between September, 1st, 2016 and December, 31st, 2016, this incidence increased to 11.4, peaking in the first trimester of 2017, with 20.8 new CRE-positive/1000 patients-day, despite the control measures already in place (Figure 1). Altogether, from September 1st, 2016 to March 31st, 2017, a total of 29 patients became CRE carriers, 11 (38%) of them developed bacteremia, with a mortality rate of 54.5%. The most frequent underlying malignancies in CRE-positive patients were acute leukemia (16/29, 55.2%) and non-Hodgkin lymphomas (6/29, 20.7%). The underlying malignancy had no impact in mortality rates associated with CRE bacteremia. Table 1 summarizes the characteristics of CRE-positive patients.In the three-month period following the intervention, the incidence of new CRE carriers fell sharply: only 2 patients became CRE-positive in this period, resulting in an incidence of 2.8/1000 patients-day, with no new bacteremia episodes. In total 5 patients (3 colonized prior and 2 after the intervention) received SDD, of which 2/5 (40%) developed bacteremia while receiving gentamycin. We also observed a reduction in the acute leukemia mortality rate in the comparison between the first and second trimester of 2017 (before and after the intervention): 36.4% vs.14.3% (p= 0.6 by Fisher's Exact Test). CONCLUSIONSWe report the successful use of an inexpensive and simple bundle of interventions to control an outbreak of CRE in an onco-hematological inpatient unit, which positively impacted on mortality, with a substantial 2.5-fold reduction in the mortality of acute leukemia patients. Although many of these interventions have already been described in this setting, the cohorting of severely neutropenic patients in single-bed rooms, irrespective of CRE status, as an effective measure has never been reported. Given the rapid and persistent decrease in the incidence of new CRE-positive patients, we believe that this component was crucial for the success of this bundle. A longer follow-up is needed to assess whether SDD for CRE carriers is effective in preventing bacteremia. The increasing number of reports of CRE outbreaks in onco-hematological patients from different parts of the world highlight the importance of these findings. [Display omitted] DisclosuresOzelo:Novo Nordisk: Consultancy, Research Funding, Speakers Bureau; Biogen: Consultancy, Research Funding, Speakers Bureau; Pfizer: Consultancy, Research Funding, Speakers Bureau; Roche: Consultancy, Speakers Bureau; Shire: Consultancy, Research Funding, Speakers Bureau; CSL Behing: Consultancy; Grifols: Speakers Bureau.

Selective digestive decontamination with oral colistin plus gentamicin for persistent bacteraemia caused by non-carbapenemase-producing carbapenem-resistant Klebsiella pneumoniae in a neutropenic patient.

BackgroundCarbapenem-resistant Klebsiella pneumoniae (CRKp) have become an increasing public health problem worldwide. While most CRKp around the world harbour a carbapenemase enzyme, the clinical relevance of non-carbapenemase-producing CRKp (non-CP-CRKp) is increasingly recognized. Selective digestive decontamination (SDD) has been proven successful as a decolonization strategy for patients colonized with Gram-negatives in the ICU. However, it is not regularly used to treat invasive infections.ObjectivesTo report the use of SDD as a useful strategy for managing recalcitrant CRKp bloodstream infections.Patients and methodsWe present a neutropenic patient with a recalcitrant bloodstream infection with non-CP-CRKp treated with SDD. Besides, genomic analyses of five isolates of non-CP-CRKp was performed.ResultsAfter 11 days of SDD treatment with oral colistin and gentamicin, bacteraemia was successfully eradicated. Genomic analysis indicates a fully carbapenem-resistant phenotype evolved in vivo and suggests that the mechanism of carbapenem resistance in our strains relates to gene amplification of narrow-spectrum β-lactamases.ConclusionsOur report highlights that SDD might be a useful strategy to manage CRKp bloodstream infections, when intestinal translocation is the likely source of the bacteraemia. In addition, the development of a resistant phenotype during therapy is worrisome as therapies directed against these organisms are likely to favour the amplification process.

Reducing the dosing frequency of selective digestive tract decontamination to three times daily provides effective decontamination of Gram-negative bacteria

This study evaluated the effectiveness of selective digestive tract decontamination (SDD) application three times daily (t.i.d.) compared to the standard four times daily (q.i.d.). Retrospective equivalence (combined non-inferiority and non-superiority design) study with a before-and-after design on a tertiary ICU in which the SDD frequency was reduced from q.i.d. to t.i.d. All patients with ICU admissions ≥72h and with ≥2 surveillance cultures collected on different dates were included in this study. We compared successful decontamination of Gram-negative bacteria (GNB). Furthermore, time to decontamination, ICU-acquired GNB bacteraemia and 28-day mortality were compared between the two groups. In total 1958 ICU admissions (1236 q.i.d., 722 t.i.d). Decontamination was achieved during the first week of admission in 77% and 76% of patients receiving SDD q.i.d and t.i.d., respectively. Successful decontamination within 14 days (without consecutive acquisition of Gram-negative bacteria) was achieved in 69.3% of the admissions with q.i.d. versus 66.8% in t.i.d. SDD (p-value = 0.2519). The proportions of successful decontamination of GNB were equivalent in both groups (−0.025, 98% CI: −0.087; 0.037). There was no significant difference in time to decontamination between the two regimens (log-rank test p-value = 0.55). Incidence (episodes/1000 days) of ICU-acquired GNB bacteraemia was 0.9 in both groups, and OR for death at day 28 in the t.i.d. group compared to the q.i.d. group was 0.99 (95% confidence interval, 0.80–1.21). This study shows that a t.i.d. application regimen achieves similar outcomes to the standard q.i.d. regime, for both microbiological and clinical outcome measures.

Topical antibiotic prophylaxis to reduce respiratory tract infections and mortality in adults receiving mechanical ventilation.

Topical antibiotic prophylaxis to reduce respiratory tract infections and mortality in adults receiving mechanical ventilation.

Current progress of research on intestinal bacterial translocation

Under normal conditions, the intestinal flora and the body are in dynamic equilibrium. When the barrier function of the intestinal tract is damaged due to various reasons, changes in the number and proportion of bacteria or spatial displacement result in bacterial translocation (BT), which ultimately leads to multiple organ dysfunction syndrome (MODS). Endogenous infections and endotoxemia caused by intestinal flora and endotoxin translocation are the origins of inflammatory responses, and the intestinal tract is the organ in which MODS both initiates and targets. Only by ensuring the integrity of the intestinal mucosal barrier can intestinal BT be effectively prevented. Elimination of the primary disease and maintaining blood and oxygen supply to the intestine is the most basic treatment. Early initiation of the intestinal tract, establishment of enteral nutrition, and selective digestive decontamination are also highly effective treatments. Early diagnosis, intervention, or prevention of BT may be a new avenue or important connection in the treatment of various diseases. The mechanism of BT, detection techniques, prevention and treatment, and its interaction with parenteral diseases were reviewed.

Prevention of Ventilator-Associated Pneumonia in the Intensive Care Unit: A Review of the Clinically Relevant Recent Advancements

Ventilator-associated pneumonia (VAP) is one of the most commonly encountered hospital-acquired infections in intensive care units and is associated with significant morbidity and high costs of care. The pathophysiology, epidemiology, treatment and prevention of VAP have been extensively studied for decades, but a clear prevention strategy has not yet emerged. In this article we will review recent literature pertaining to evidence-based VAP-prevention strategies that have resulted in clinically relevant outcomes. A multidisciplinary strategy for prevention of VAP is recommended. Those interventions that have been shown to have a clinical impact include the following: (i) Non-invasive positive pressure ventilation for able patients, especially in immunocompromised patients, with acute exacerbation of chronic obstructive pulmonary disease or pulmonary oedema, (ii) Sedation and weaning protocols for those patients who do require mechanical ventilation, (iii) Mechanical ventilation protocols including head of bed elevation above 30 degrees and oral care, and (iv) Removal of subglottic secretions. Other interventions, such as selective digestive tract decontamination, selective oropharyngeal decontamination and antimicrobial-coated endotracheal tubes, have been tested in different studies. However, the evidence for the efficacy of these measures to reduce VAP rates is not strong enough to recommend their use in clinical practice. In numerous studies, the implementation of VAP prevention bundles to clinical practice was associated with a significant reduction in VAP rates. Future research that considers clinical outcomes as primary endpoints will hopefully result in more detailed prevention strategies.

Selective digestive decontamination solution used as \u201clock therapy\u201d prevents and eradicates bacterial biofilm in an in vitro bench-top model

BackgroundMost preventing measures for reducing ventilator-associated pneumonia (VAP) are based mainly on the decolonization of the internal surface of the endotracheal tubes (ETTs). However, it has been demonstrated that bacterial biofilm can also be formed on the external surface of ETTs. Our objective was to test in vitro the efficacy of selective digestive decontamination solution (SDDs) onto ETT to prevent biofilm formation and eradicate preformed biofilms of three different microorganisms of VAP.MethodsWe used an in vitro model in which we applied, at the subglottic space of ETT, biofilms of either P. aeruginosa ATCC 15442, or E. coli ATCC 25922, or S. aureus ATCC 29213, and the SDDs at the same time (prophylaxis) or after 72 h of biofilm forming (treatment). ETT were incubated during 5 days with a regimen of 2 h-locks. ETT fragments were analyzed by sonication and confocal laser scanning microscopy to calculate the percentage reduction of cfu and viable cells, respectively.ResultsMedian (IQR) percentage reduction of live cells and cfu/ml counts after treatment were, respectively, 53.2% (39.4%—64.1%) and 100% (100%–100.0%) for P. aeruginosa, and 67.9% (46.7%–78.7%) and 100% (100%–100.0%) for E. coli. S. aureus presented a complete eradication by both methods. After prophylaxis, there were absence of live cells and cfu/ml counts for all microorganisms.ConclusionsSDDs used as “lock therapy” in the subglottic space is a promising prophylactic approach that could be used in combination with the oro-digestive decontamination procedure in the prevention of VAP.

Efficacy of a hospital policy of selective digestive decontamination for carbapenem-resistant Enterobacterales carriers: prospective before–after study

A single-centre interrupted time series quasi-experimental study was undertaken to assess whether a hospital policy of selective digestive decontamination (SDD, gentamicin/amikacin with neomycin) administered to carbapenem-resistant Enterobacterales (CRE) carriers would reduce the duration of carriage and contain the spread of CRE. No significant difference in time to CRE eradication was observed between the observation (12 months, 120 patients) and intervention (12 months, 101 patients) periods. No change in the trend of new in-hospital CRE acquisitions or bacteraemia during the intervention was detected. As such, administration of SDD to CRE carriers was not effective for the eradication of carriage or controlling in-hospital CRE transmissions.

Gut Microbiota Modulation: Implications for Infection Control and Antimicrobial Stewardship.

The human microbiome comprises a complex ecosystem of microbial communities that exist within the human body, the largest and most diverse of which are found within the human intestine. It has been increasingly implicated in human health and diseases, demonstrably playing a critical role in influencing host immune response, protection against pathogen overgrowth, biosynthesis, and metabolism. As our understanding of the links between the gut microbiota with host immunity and infectious diseases deepens, there is a greater need to incorporate methods of modulating it as a means of therapy or infection prevention in daily clinical practice. Traditional antimicrobial stewardship principles have been evaluated to assess their impact on the gut microbiota diversity and the consequent repercussions, taking into consideration antibiotic pharmacokinetic and pharmacodynamic properties. Novel strategies of selective digestive decontamination and fecal microbiota transplantation to regulate the gut microbiota have also been tested in different conditions with variable results. This review seeks to provide an overview of the available literature on the modulation of the gut microbiota and its implications for infection control and antimicrobial stewardship. With increased understanding, gut microbiota profiling through metataxonomic analysis may provide further insight into modulating microbial communities in the context of infection prevention and control.

Decreased duration of intravenous cephalosporins in intensive care unit patients with selective digestive decontamination: a retrospective before-and-after study.

Selective digestive decontamination (SDD) reduces the rate of infection and improves the outcomes of patients admitted to an intensive care unit (ICU). A risk associated with its use is the development of multi-drug-resistant organisms. We hypothesized that a 1-day reduction in systemic antimicrobial exposure in the SDD regimen would not affect the outcomes of our patients. In this before-and-after study design, 199 patients and 248 patients were included in a 3-day SDD group and a 2-day SDD group, respectively. The rates of hospital-acquired pneumonia and ICU infections were similar in both groups. The rates of bloodstream infection and bacteriuria were significantly lower in the 2-day SDD group than in the 3-day SDD group. Compared with the patients in the 3-day group, the patients in the 2-day SDD group received fewer antibiotics and less exposure to mechanical ventilation, and they used fewer ICU resources. The rates of ICU mortality and 28-day mortality were similar in both groups. The incidence of multi-drug-resistant organisms was similar in both groups. Within the limitations inherent to our study design, reducing the exposure of prophylactic systemic antibiotics in the SDD setting from 3 days to 2 days was not associated with impaired outcomes. Future randomized controlled trials should be conducted to test this hypothesis and investigate the effects on the development of multi-drug resistant organisms.Electronic supplementary materialThe online version of this article (10.1007/s10096-020-03966-w) contains supplementary material, which is available to authorized users.