Use of selective decontamination of the digestive tract in United Kingdom intensive care units*

Anti-infectious decontamination strategies in Dutch intensive care units: A survey study on contemporary practice and heterogeneity

PURPOSE

Despite increasing evidence and updated national guidelines, practice of anti-infectious strategies appears to vary in the Netherlands. This study aimed to determine the variation of current practices of anti-infectious strategies in Dutch ICUs.

MATERIALS AND METHODS

In 2018 and 2019 an online survey of all Dutch ICUs was conducted with detailed questions on their anti-infectious strategies.

RESULTS

89% (63 of 71) of the Dutch ICUs responded to the online survey. The remaining ICUs were contacted by telephone. 47 (66%) of the Dutch ICUs used SDD, 14 (20%) used SOD and 10 (14%) used neither SDD nor SOD. Within these strategies considerable heterogeneity was observed in the start criteria of SDD/SOD, the regimen adjustments based on microbiological surveillance and the monitoring of the interventions.

CONCLUSIONS

The proportion of Dutch ICUs applying SDD or SOD increased over time. Considerable heterogeneity in the regimens was reported. The impact of the observed differences within SDD and SOD practices on clinical outcome remains to be explored.

Discrepancies in Control Group Mortality Rates Within Studies Assessing Topical Antibiotic Strategies to Prevent Ventilator-Associated Pneumonia: An Umbrella Review

Supplemental Digital Content is available in the text.

Objectives:

To test the postulate that concurrent control patients within ICUs studying topical oropharyngeal antibiotics to prevent ventilator-associated pneumonia and mortality would experience spillover effects from the intervention.

Data Sources:

Studies cited in 15 systematic reviews of various topical antibiotic and other infection prevention interventions among ICU patients.

Study Selection:

Studies of topical antibiotics, stratified into concurrent control versus nonconcurrent control designs. Studies of nondecontamination-based infection prevention interventions provide additional points of reference. Studies with no infection prevention intervention provide the mortality benchmark. Data from additional studies and data reported as intention to treat were used within sensitivity tests.

Data Extraction:

Mortality incidence proportion data, mortality census, study characteristics, group mean age, ICU type, and study publication year.

Data Synthesis:

Two-hundred six studies were included. The summary effect sizes for ventilator-associated pneumonia and mortality prevention derived in the 15 systematic reviews were replicated. The mean ICU mortality incidence for concurrent control groups of topical antibiotic studies (28.5%; 95% CI, 25.0–32.3; n = 41) is higher versus the benchmark (23.7%; 19.2–28.5%; n = 34), versus nonconcurrent control groups (23.5%; 19.3–28.3; n = 14), and versus intervention groups (24.4%; 22.1–26.9; n = 62) of topical antibiotic studies. In meta-regression models adjusted for group-level characteristics such as group mean age and publication year, concurrent control group membership within a topical antibiotic study remains associated with higher mortality (p = 0.027), whereas other group memberships, including membership within an antiseptic study, are each neutral (p = not significant).

Conclusions:

Within topical antibiotic studies, the concurrent control group mortality incidence proportions are inexplicably high, whereas the intervention group mortality proportions are paradoxically similar to a literature-derived benchmark. The unexplained ventilator-associated pneumonia and mortality excess in the concurrent control groups implicates spillover effects within studies of topical antibiotics. The apparent ventilator-associated pneumonia and mortality prevention effects require cautious interpretation.

Digestive decontamination in burn patients: A systematic review of randomized clinical trials and observational studies

OBJECTIVE

The objective of this systematic review is to assess the effect of selective digestive decontamination (SDD) or non-absorbable enteral antibiotics (EA) on mortality, the incidence of infection and its adverse effects in burn patients.

MATERIAL AND METHODS

Systematic review of randomized clinical trials (RCT) or observational studies enrolling burn patients, and comparing SDD or EA prophylaxis with placebo or no treatment. The search includes Pubmed/Medline, EMBASE, WOS, Cochrane Library (1970-2015). Bibliographic references were also reviewed, as well as communications presented at conferences (2012-2015), without language restrictions. Two reviewers inspected each reference identified by the search independently; the risk of bias was assessed with the Cochrane Collaboration method for RCT and the Newcastle Ottawa Scale for observational studies.

RESULTS

Five RCT and 5 observational studies were identified enrolling a total of 1680 patients. The overall methodological quality of the studies was poor. The pooled effect of RCT using EA was OR: 0.62 (95% CI: 0.20-1.94). The only RCT using SDD reported OR 0.20 (95% CI: 0.09-0.81). The incidence of Enterobacteriaceae bloodstream was lower in cases treated with SDD or EA. The incidence of pneumonia was only reduced in the studies using SDD. None of the studies reported an increase in antibiotic resistance but in one RCT SDD was associated to an increase in methicillin-resistant Staphylococcus aureus infections, that was controlled with enteral vancomycin.

CONCLUSIONS

SDD and EA have shown a beneficial effect in burn patients. Both practices are safe. Higher quality RCTs should be conducted to properly assess the efficacy and safety of SDD in this population.

A systematic review and meta-analysis of perioperative oral decontamination in patients undergoing major elective surgery

Background

Oral antiseptics reduce nosocomial infections and ventilator-associated pneumonia in critically ill medical and surgical patients intubated for prolonged periods. However, the role of oral antiseptics given before and after planned surgery is not clear. The aim of this systematic review and meta-analysis is to determine the effect of oral antiseptics (chlorhexidine or povidone–iodine) when administered before and after major elective surgery.

Methods

Searches were conducted of the MEDLINE, EMBASE and Cochrane databases. The analysis was performed using the random-effects method and the risk ratio (RR) with 95 % confidence interval (CI).

Results

Of 1114 unique identified articles, perioperative chlorhexidine was administered to patients undergoing elective surgery in four studies. This identified 2265 patients undergoing elective cardiac surgery, of whom 1093 (48.3 %) received perioperative chlorhexidine. Postoperative pneumonia and nosocomial infections were observed in 5.3 and 20.2 % who received chlorhexidine compared to 10.4 and 31.3 % who received a control preparation, respectively. Oral perioperative chlorhexidine significantly reduced the risk of postoperative pneumonia (RR = 0.52; 95 % CI 0.39–0.71; p < 0.01) and overall nosocomial infections (RR = 0.65; 95 % CI 0.52–0.81; p < 0.01), with no effect on in-hospital mortality (RR = 1.01; 95 % CI 0.49–2.09; p = 0.98).

Conclusions

Perioperative oral chlorhexidine significantly decreases the incidence of nosocomial infection and postoperative pneumonia in patients undergoing elective cardiac surgery. There are no randomised controlled studies of this simple and cheap intervention in patients undergoing elective non-cardiac surgery.

Trial Registration

This systematic review was registered with the International prospective register of systematic reviews (PROSPERO). The registration number is CRD42015016063.

Antibiotic-Induced Within-Host Resistance Development of Gram-Negative Bacteria in Patients Receiving Selective Decontamination or Standard Care

OBJECTIVE

To quantify antibiotic-associated within-host antibiotic resistance acquisition rates in Pseudomonas aeruginosa, Klebsiella species, and Enterobacter species from lower respiratory tract samples of ICU patients receiving selective digestive decontamination, selective oropharyngeal decontamination, or standard care.

DESIGN

Prospective cohort.

SETTING

This study was nested within a cluster-randomized crossover study of selective digestive decontamination and selective oropharyngeal decontamination in 16 ICUs in The Netherlands.

PATIENTS

Eligible patients were those colonized in the respiratory tract with P. aeruginosa, Klebsiella species, or Enterobacter species susceptible to one of the marker antibiotics and with at least two subsequent microbiological culture results from respiratory tract samples available.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Antibiotic resistance acquisition rates were defined as the number of conversions from susceptible to resistant for a specific antibiotic per 100 patient-days or 100 days of antibiotic exposure within an individual patient. The hazard of antibiotic use for resistance development in P. aeruginosa was based on time-dependent Cox regression analysis. Findings of this study cohort were compared with those of a previous cohort of patients not receiving selective digestive decontamination/selective oropharyngeal decontamination. Numbers of eligible patients were 277 for P. aeruginosa, 174 for Klebsiella species, and 106 for Enterobacter species. Resistance acquisition rates per 100 patient-days ranged from 0.2 (for colistin and ceftazidime in P. aeruginosa and for carbapenems in Klebsiella species) to 3.0 (for piperacillin-tazobactam in P. aeruginosa and Enterobacter species). For P. aeruginosa, the acquisition rates per 100 days of antibiotic exposure ranged from 1.4 for colistin to 4.9 for piperacillin-tazobactam. Acquisition rates were comparable for patients receiving selective digestive decontamination/selective oropharyngeal decontamination and those receiving standard care. Carbapenem exposure had the strongest association with resistance development (adjusted hazard ratio, 4.2; 95% CI, 1.1-15.6).

CONCLUSION

Within-host antibiotic resistance acquisition rates for systemically administered antibiotics were comparable between patients receiving selective decontamination and those receiving standard care and were highest during carbapenem use.

Fighting antibiotic resistance in the intensive care unit using antibiotics

Antibiotic resistance is a global and increasing problem that is not counterbalanced by the development of new therapeutic agents. The prevalence of antibiotic resistance is especially high in intensive care units with frequently reported outbreaks of multidrug-resistant organisms. In addition to classical infection prevention protocols and surveillance programs, counterintuitive interventions, such as selective decontamination with antibiotics and antibiotic rotation have been applied and investigated to control the emergence of antibiotic resistance. This review provides an overview of selective oropharyngeal and digestive tract decontamination, decolonization of methicillin-resistant Staphylococcus aureus and antibiotic rotation as strategies to modulate antibiotic resistance in the intensive care unit.

Colistin and tobramycin resistance during long- term use of selective decontamination strategies in the intensive care unit: a post hoc analysis

Introduction

Selective decontamination of the digestive tract (SDD) and selective oropharyngeal decontamination (SOD) have been shown to improve intensive care unit (ICU) patients’ outcomes. The aim of this study was to determine the effects of long-term use of SDD and SOD on colistin and tobramycin resistance among gram-negative bacteria.

Methods

We performed a post hoc analysis of two consecutive multicentre cluster-randomised trials with crossover of interventions. SDD and SOD were alternately but continuously used during 7 years in five Dutch ICUs participating in two consecutive cluster-randomised trials. In both trials, to measure colistin and tobramycin resistance among gram-negative bacteria, rectal and respiratory samples were obtained monthly from all patients present in the ICU.

Results

The prevalence of tobramycin resistance in respiratory and rectal samples decreased significantly during long-term use of SOD and SDD. (rectal samples risk ratio (RR) 0.35 (0.23 to 0.53); respiratory samples RR 0.48 (0.32 to 0.73), SDD compared to standard care). Colistin resistance in rectal and respiratory samples did not change (rectal samples RR 0.63 (0.29 to 1.38); respiratory samples RR 1.26 (0.35 to 4.57), SDD compared to standard care).

Conclusions

In this study, in a setting with low antimicrobial resistance rates, the prevalence of resistance against colistin and tobramycin among gram-negative isolates did not increase during a mean of 7 years of SDD or SOD use.

Electronic supplementary material

The online version of this article (doi:10.1186/s13054-015-0838-4) contains supplementary material, which is available to authorized users.

Observational study of current use of selective decontamination of the digestive tract in UK critical care units

BACKGROUND

Evidence supporting selective decontamination of the digestive tract (SDD) is reasonably strong. We set out to determine use in UK critical care units and to compare patient outcomes between units that do and those that do not use SDD.

METHODS

A total of 250 UK general critical care units were surveyed. Case mix, outcomes, and lengths of stay for admissions to SDD units (with and without an i.v. component) and non-SDD units were compared using data from the Intensive Care National Audit & Research Centre Case Mix Programme database.

RESULTS

A response was received from all the 250 critical care units surveyed. Of these, 13 (5.2%) reported using SDD on some or all admissions, and of these, 3 reported using an i.v. component. Data on 284,690 admissions (April 2008-March 2011) from units reporting to the ICNARC Case Mix Programme (CMP) were included in the analyses. Admissions to SDD (n=196) and non-SDD (n=9) units were a similar case mix with similar infection rates and average lengths of stay in the unit and hospital. There was no difference in risk-adjusted unit or hospital mortality. The rate of unit-acquired infections in blood was significantly lower in SDD units using an i.v. component.

CONCLUSIONS

Use of SDD in UK critical care is very low. The rate of unit-acquired infections in blood was significantly lower in SDD units using an i.v. component, but did not translate into a difference in acute hospital mortality or length of stay. There is a need to better understand the barriers to adoption of SDD into clinical practice and such work is underway.

Selective digestive or oropharyngeal decontamination and topical oropharyngeal chlorhexidine for prevention of death in general intensive care: systematic review and network meta-analysis

OBJECTIVES

To determine the effect on mortality of selective digestive decontamination, selective oropharyngeal decontamination, and topical oropharyngeal chlorhexidine in adult patients in general intensive care units and to compare these interventions with each other in a network meta-analysis.

DESIGN

Systematic review, conventional meta-analysis, and network meta-analysis. Medline, Embase, and CENTRAL were searched to December 2012. Previous meta-analyses, conference abstracts, and key journals were also searched. We used pairwise meta-analyses to estimate direct evidence from intervention-control trials and a network meta-analysis within a Bayesian framework to combine direct and indirect evidence.

INCLUSION CRITERIA

Prospective randomised controlled trials that recruited adult patients in general intensive care units and studied selective digestive decontamination, selective oropharyngeal decontamination, or oropharyngeal chlorhexidine compared with standard care or placebo.

RESULTS

Selective digestive decontamination had a favourable effect on mortality, with a direct evidence odds ratio of 0.73 (95% confidence interval 0.64 to 0.84). The direct evidence odds ratio for selective oropharyngeal decontamination was 0.85 (0.74 to 0.97). Chlorhexidine was associated with increased mortality (odds ratio 1.25, 1.05 to 1.50). When each intervention was compared with the other, both selective digestive decontamination and selective oropharyngeal decontamination were superior to chlorhexidine. The difference between selective digestive decontamination and selective oropharyngeal decontamination was uncertain.

CONCLUSION

Selective digestive decontamination has a favourable effect on mortality in adult patients in general intensive care units. In these patients, the effect of selective oropharyngeal decontamination is less certain. Both selective digestive decontamination and selective oropharyngeal decontamination are superior to chlorhexidine, and there is a possibility that chlorhexidine is associated with increased mortality.

The views of health care professionals about selective decontamination of the digestive tract: an international, theoretically informed interview study

PURPOSE

Selective decontamination of the digestive tract (SDD) as a prophylactic intervention improves hospital-acquired infection and survival rates. Uptake of SDD is low and remains controversial. This study applied the theoretical domains framework to assess intensive care unit clinicians' views about SDD in regions with limited or no adoption of SDD.

MATERIALS AND METHODS

Participants were health professionals with "decisional authority" for the adoption of SDD. Semistructured interviews were conducted as the first round of a Delphi study. Views about SDD adoption, delivery, and further SDD research were explored. Directed content analysis of interview data identified subthemes, which informed item development for subsequent Delphi rounds. Linguistic features of interview data were also explored.

RESULTS

One hundred forty-one participants provided interview data. Fifty-six subthemes were identified; 46 were common across regions. Beliefs about consequences were the most widely elaborated theme. Linguistic features of how participants discussed SDD included caution expressed when discussing the risks and benefits and words such as "worry," "anxiety," and "fear" when discussing potential antibiotic resistance associated with SDD.

CONCLUSIONS

We identified salient beliefs, barriers, and facilitators to SDD adoption and delivery. What participants said about SDD and the way in which they said it demonstrated the degree of clinical caution, uncertainty, and concern that SDD evokes.

Implementing selective digestive tract decontamination in the intensive care unit: A qualitative analysis of nurse-identified considerations

OBJECTIVE

To describe factors senior critical care nurses identify as being important to address when introducing selective digestive tract decontamination (SDD) in the clinical setting.

BACKGROUND

Critically ill patients are at risk of developing ventilator-associated pneumonia (VAP). SDD is one strategy shown to prevent VAP and possibly improve survival in the critically ill.

METHODS

We performed a secondary analysis of qualitative data obtained from 20 interviews. An inductive thematic analysis approach was applied to data obtained from senior critical care nurses during phase two of a multi-methods study.

RESULTS

There were four primary considerations identified that should be addressed or considered prior to implementation of SDD. These considerations included education of health care professionals, patient comfort, compatibility of SDD with existing practices, and cost.

CONCLUSIONS

Despite a lack of experience with, or knowledge of SDD, nurses were able to articulate factors that may influence its implementation and delivery. Organizations or researchers considering implementation of SDD should include nurses as key members of the implementation team.

Clinical stakeholders' opinions on the use of selective decontamination of the digestive tract in critically ill patients in intensive care units: an international Delphi study

Introduction

Selective decontamination of the digestive tract (SDD) is a prophylactic antibiotic regimen that is not widely used in practice. We aimed to describe the opinions of key ‘stakeholders’ about the validity of the existing evidence base, likely consequences of implementation, relative importance of their opinions in influencing overall practice, likely barriers to implementation and perceptions of the requirement for further research to inform the decision about whether to embark on a further large randomised controlled trial.

Methods

This was a Delphi study informed by comprehensive framework of possible determinants of health professionals’ behaviour to study Critical Care practice in four countries. There were four key stakeholder participant groups including ICU physicians, pharmacists, clinical leads, and clinical microbiologists/ infectious disease physicians. Round one comprised participant interviews and Rounds two and three were online questionnaires using Delphi method.

Results

In this study, 141 participants were recruited of whom 82% were retained. Participants rated themselves as knowledgeable about SDD. Antibiotic resistance was identified as the most important issue. SDD was seen as a low clinical priority but few participants reported strong opposition. There was moderate agreement that research to date has not adequately addressed concerns about antibiotic resistance and lacks generalizability. Participants indicated equipoise with regard to benefits and harms of SDD, and indicated strong support for a further randomised trial.

Conclusions

Clinicians have clinical equipoise about the effectiveness of SDD. Future research requires longer follow up to assess antibiotic resistance as well as greater validity/generalizability to provide definitive answers on the effectiveness of decontamination and effects on antibiotic resistance. SDD was regarded as not being a high clinical priority, which may limit future trial participation. These results have identified that further large randomised controlled trial of SDD in critical care is both warranted and appropriate.

Clinical components and associated behavioural aspects of a complex healthcare intervention: multi-methods study of selective decontamination of the digestive tract in critical care

BACKGROUND

This study sought to identify and describe the clinical and behavioural components (e.g. the what, how, when, where and by whom) of 'selective decontamination of the digestive tract' (SDD) as routinely implemented in the care of critically ill patients.

METHODS

Multi-methods study, consisting of semi-structured observations of SDD delivery, interviews with clinicians and documentary analysis, conducted in two ICUs in the UK that routinely deliver SDD. Data were analysed within-site to describe clinical and behavioural SDD components and synthesised across-sites to describe SDD in context.

RESULTS

SDD delivery involved multiple behaviours extending beyond administration of its clinical components. Not all behaviours were specified in relevant clinical documentation. Overall, SDD implementation and delivery included: adoption (i.e. whether to implement SDD), operationalisation (i.e. implementing SDD into practice), provision (i.e. delivery of SDD) and surveillance (i.e. monitoring the ecological effects). Implementation involved organisational, team and individual-level behaviours. Delivery was perceived as easy by individual staff, but displayed features of complexity (including multiple interrelated behaviours, staff and contexts).

CONCLUSIONS

This study is the first to formally outline the full spectrum of clinical and behavioural aspects of SDD. It identified points in the delivery process where complex behaviours occur and outlined how SDD can be interpreted and applied variably in practice. This comprehensive specification allows greater understanding of how this intervention could be implemented in units not currently using it, or replicated in research studies. It also identified strategies required to adopt SDD and to standardise its implementation.

Effect of selective decontamination on antimicrobial resistance in intensive care units: a systematic review and meta-analysis

BACKGROUND

Many meta-analyses have shown reductions in infection rates and mortality associated with the use of selective digestive decontamination (SDD) or selective oropharyngeal decontamination (SOD) in intensive care units (ICUs). These interventions have not been widely implemented because of concerns that their use could lead to the development of antimicrobial resistance in pathogens. We aimed to assess the effect of SDD and SOD on antimicrobial resistance rates in patients in ICUs.

METHODS

We did a systematic review of the effect of SDD and SOD on the rates of colonisation or infection with antimicrobial-resistant pathogens in patients who were critically ill. We searched for studies using Medline, Embase, and Cochrane databases, with no limits by language, date of publication, study design, or study quality. We included all studies of selective decontamination that involved prophylactic application of topical non-absorbable antimicrobials to the stomach or oropharynx of patients in ICUs, with or without additional systemic antimicrobials. We excluded studies of interventions that used only antiseptic or biocide agents such as chlorhexidine, unless antimicrobials were also included in the regimen. We used the Mantel-Haenszel model with random effects to calculate pooled odds ratios.

FINDINGS

We analysed 64 unique studies of SDD and SOD in ICUs, of which 47 were randomised controlled trials and 35 included data for the detection of antimicrobial resistance. When comparing data for patients in intervention groups (those who received SDD or SOD) versus data for those in control groups (who received no intervention), we identified no difference in the prevalence of colonisation or infection with Gram-positive antimicrobial-resistant pathogens of interest, including meticillin-resistant Staphylococcus aureus (odds ratio 1·46, 95% CI 0·90-2·37) and vancomycin-resistant enterococci (0·63, 0·39-1·02). Among Gram-negative bacilli, we detected no difference in aminoglycoside-resistance (0·73, 0·51-1·05) or fluoroquinolone-resistance (0·52, 0·16-1·68), but we did detect a reduction in polymyxin-resistant Gram-negative bacilli (0·58, 0·46-0·72) and third-generation cephalosporin-resistant Gram-negative bacilli (0·33, 0·20-0·52) in recipients of selective decontamination compared with those who received no intervention.

INTERPRETATION

We detected no relation between the use of SDD or SOD and the development of antimicrobial-resistance in pathogens in patients in the ICU, suggesting that the perceived risk of long-term harm related to selective decontamination cannot be justified by available data. However, our study indicates that the effect of decontamination on ICU-level antimicrobial resistance rates is understudied. We recommend that future research includes a non-crossover, cluster randomised controlled trial to assess long-term ICU-level changes in resistance rates.

FUNDING

None.

Prevention of ventilator-associated pneumonia through aspiration of subglottic secretions: a systematic review and meta-analysis

Ventilator-associated pneumonia (VAP) is a subset of hospital-acquired pneumonias and is a serious, sometimes fatal, complication in patients who need mechanical ventilation. In addition, pay-for-performance initiative has placed increased emphasis on preventing nosocomial infections including VAP. Facilities may not be reimbursed for costs associated with prevalence infections. This article presents a review and meta-analysis of the prevention of VAP through the aspiration of subglottic secretion.

Antibiotics or probiotics as preventive measures against ventilator-associated pneumonia: a literature review

Introduction

Mechanically ventilated critically ill patients frequently develop ventilator-associated pneumonia (VAP), a life-threatening complication. Proposed preventive measures against VAP include, but are not restricted to, selective decontamination of the digestive tract (SDD), selective oropharyngeal decontamination (SOD) and the use of probiotics. Probiotics are live bacteria that could have beneficial effects on the host by altering gastrointestinal flora. Similar to SDD and SOD, a prescription of probiotics aims at the prevention of secondary colonization of the upper and/or lower digestive tract.

Methods

We performed a literature review to describe the differences and similarities between SDD/SOD and probiotic preventive strategies, focusing on (a) efficacy, (b) risks, and (c) the routing of these strategies.

Results

Reductions in the incidence of VAP have been achieved with SDD and SOD. Two large randomized controlled trials even showed reduced mortality with these preventive strategies. Randomized controlled trials of probiotic strategies also showed a reduction of the incidence of VAP, but trials were too small to draw firm conclusions. Preventive strategies with antibiotics and probiotics may be limited due to the risk of emerging resistance to the locally applied antibiotics and the risk of probiotic-related infections, respectively. The majority of trials of SDD and SOD did not exhaustively address the issue of emerging resistance. Likewise, trials of probiotic strategies did not adequately address the risk of colonization with probiotics and probiotic-related infection. In studies of SDD and SOD the preventive strategy aimed at decontamination of the oral cavity, throat, stomach and intestines, and the oral cavity and throat, respectively. In the vast majority of studies of probiotic therapy the preventive strategy aimed at decontamination of the stomach and intestines.

Conclusions

Prophylactic use of antibiotics in critically ill patients is effective in reducing the incidence of VAP. Probiotic strategies deserve consideration in future well-powered trials. Future studies are needed to determine if preventive antibiotic and probiotic strategies are safe with regard to development of antibiotic resistance and probiotic infections. It should be determined whether the efficacy of probiotics improves when these agents are provided to the mouth and the intestines simultaneously.

A study of the perceived risks, benefits and barriers to the use of SDD in adult critical care units (the SuDDICU study)

BACKGROUND

Hospital acquired infections are a major cause of morbidity and mortality and markedly increased health care costs. Critically ill patients who require management in an Intensive Care Unit are particularly susceptible to these infections which are associated with a very high mortality. Selective decontamination of the digestive tract (SDD) may reduce these infections and improve mortality but it has not been widely adopted into practice. We aim to 1. Clarify reasons why clinicians have avoided implementing SDD into clinical practice despite the current best-evidence 2. Describe barriers to SDD implementation and 3. Identify what further evidence is required before full scale clinical implementation would be considered appropriate and feasible.

METHODS

We have developed an international 'multi-lens' approach to investigate SDD from several perspectives. In case studies we will identify accounts of implementation of SDD in practice, in terms of the behaviours performed by the full range of individual clinicians, accounts of how SDD was first introduced into the Unit and specific content that may be used to populate the content of behaviour change techniques to be used in an implementation intervention and procedures to consider in order to deliver an implementation trial. In a 4 round Delphi study we will identify the range of stakeholders' beliefs, views and perceived barriers relating to the use of SDD. We will generate hypotheses about key beliefs about SDD and will inform the feasibility of any future randomised controlled trial. In large-scale nationwide postal questionnaire surveys of the state of current practice we will identify the factors predicting acceptability of an effectiveness or implementation trial using, and informed by, the theoretical domains structure. In semi-structured interviews with active international clinical trialists we will assess the feasibility of a randomised controlled trial and identify challenges and barriers to undertaking research in the field of SDD research.

DISCUSSION

We believe these methods will allow us to determine whether clinical implementation trials or further large effectiveness trials are required before full scale implementation into clinical practice.

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.

Physicians' and nurses' opinions on selective decontamination of the digestive tract and selective oropharyngeal decontamination: a survey

Introduction

Use of selective decontamination of the digestive tract (SDD) and selective oropharyngeal decontamination (SOD) in intensive care patients has been controversial for years. Through regular questionnaires we determined expectations concerning SDD (effectiveness) and experience with SDD and SOD (workload and patient friendliness), as perceived by nurses and physicians.

Methods

A survey was embedded in a group-randomized, controlled, cross-over multicenter study in the Netherlands in which, during three 6-month periods, SDD, SOD or standard care was used in random order. At the end of each study period, all nurses and physicians from participating intensive care units received study questionnaires.

Results

In all, 1024 (71%) of 1450 questionnaires were returned by nurses and 253 (82%) of 307 by physicians. Expectations that SDD improved patient outcome increased from 71% and 77% of respondents after the first two study periods to 82% at the end of the study (P = 0.004), with comparable trends among nurses and physicians. Nurses considered SDD to impose a higher workload (median 5.0, on a scale from 1 (low) to 10 (high)) than SOD (median 4.0) and standard care (median 2.0). Both SDD and SOD were considered less patient friendly than standard care (medians 4.0, 4.0 and 6.0, respectively). According to physicians, SDD had a higher workload (median 5.5) than SOD (median 5.0), which in turn was higher than standard care (median 2.5). Furthermore, physicians graded patient friendliness of standard care (median 8.0) higher than that of SDD and SOD (both median 6.0).

Conclusions

Although perceived effectiveness of SDD increased as the trial proceeded, both among physicians and nurses, SOD and SDD were, as compared to standard care, considered to increase workload and to reduce patient friendliness. Therefore, education about the importance of oral care and on the effects of SDD and SOD on patient outcomes will be important when implementing these strategies.

Trial registration

ISRCTN35176830.

[Decontamination. A treatment without indications]

The prevention of ventilator-associated pneumonia (VAP) is a priority in the Intensive Care Unit (ICU). To achieve this goal, clinical practice guidelines recommend the simultaneous application of a heterogeneous group of preventive measures of proven effectiveness. That is why we are presently seeing a reduction in VAP incidence to values previously considered unreachable. Better compliance with clinical practice guidelines has resulted in VAP rates approaching zero in multiple studies. Faced with the measures recommended in these guidelines, selective digestive decontamination (SDD), used together with other infection control practices, has shown efficacy in hospitals with high baseline incidence of pneumonia. However, its effectiveness in hospitals with good compliance of clinical practice guidelines and lower rates of VAP is highly unlikely. A serious drawback of DDS is the risk of favoring the selection of resistant microorganisms that can spread easily through the ICU and the hospital. With current standards of infection prevention, DDS is an unnecessary and risky measure, which should not be used on a widespread basis. Those situations in which the DDS may increase the effectiveness of properly implemented standard measures are still unknown.