Rebound Inverts the Staphylococcus aureus Bacteremia Prevention Effect of Antibiotic Based Decontamination Interventions in ICU Cohorts with Prolonged Length of Stay

Could rebound explain the paradoxical lack of prevention effect against Staphylococcus aureus blood stream infections (BSIs) with antibiotic-based decontamination intervention (BDI) methods among studies of ICU patients within the literature? Two meta-regression models were applied, each versus the group mean length of stay (LOS). Firstly, the prevention effects against S. aureus BSI [and S. aureus VAP] among 136 studies of antibiotic-BDI versus other interventions were analyzed. Secondly, the S. aureus BSI [and S. aureus VAP] incidence in 268 control and intervention cohorts from studies of antibiotic-BDI versus that among 165 observational cohorts as a benchmark was modelled. In model one, the meta-regression line versus group mean LOS crossed the null, with the antibiotic-BDI prevention effect against S. aureus BSI at mean LOS day 7 (OR 0.45; 0.30 to 0.68) inverted at mean LOS day 20 (OR 1.7; 1.1 to 2.6). In model two, the meta-regression line versus group mean LOS crossed the benchmark line, and the predicted S. aureus BSI incidence for antibiotic-BDI groups was 0.47; 0.09-0.84 percentage points below versus 3.0; 0.12-5.9 above the benchmark in studies with 7 versus 20 days mean LOS, respectively. Rebound within the intervention groups attenuated and inverted the prevention effect of antibiotic-BDI against S. aureus VAP and BSI, respectively. This explains the paradoxical findings.

Rifaximin in gut microbiota modification in acute pancreatitis: 15 years of retrospective clinical study

BACKGROUND

Gut decontamination could have some benefits in preventing infectious complications in acute pancreatitis (AP).

OBJECTIVES

To investigate whether the administration of rifaximin could have an impact on the outcomes of AP.

MATERIAL AND METHODS

We conducted a retrospective study on 373 patients with a median age of 50 years that were admitted to our Department of Gastroenterology in the years 2001-2016 with a diagnosis of AP. Patients were subclassified according to the revised Atlanta criteria: mild acute pancreatitis (MAP), moderately severe acute pancreatitis (MSAP) and severe acute pancreatitis (SAP). Thereafter, all the patients were divided into 2 groups: in the 1st group (R0) with MSAP and SAP, patients did not receive rifaximin, and in the 2nd group (R1), in the cases of MSAP and SAP, rifaximin was administered to patients at a dose of 3 × 400 mg (for at least 5 days and up to 7 days). There was no other difference in the treatment between the groups. The median duration of hospital stay, the number of infectious complications and the mortality rate were recorded for both groups.

RESULTS

A significant difference was observed between median durations of hospitalization between the groups with (R1) and without (R0) rifaximin treatment (14 days compared to 24 days, p = 0.001) and in the number of patients infected with pancreatic necrosis (7 compared to 1, p = 0.0487). However, there was no statistically significant difference between the R1 and R0 group in terms of mortality rate.

CONCLUSIONS

The results indicate that rifaximin seems to be a promising novel therapeutic option in MSAP and SAP.

Risk Factors for Renal Impairment in Adult Patients With Short Bowel Syndrome

Renal impairment is a common complication in patients with intestinal failure that is mostly caused by short bowel syndrome (SBS) and is associated with adverse outcomes that severely affect the quality of life or even survival. The prevalence and risk factors for renal impairment in patients with SBS remain unclarified. Therefore, we aimed to determine the prevalence of renal impairment and identify potential risk factors for renal impairment in adult patients with SBS. We retrospectively identified 199 patients diagnosed with SBS admitted to the Department of General Surgery between January 1, 2012 and January 1, 2019, from a prospectively maintained database. Overall, 56 patients (28.1%) with decreased renal function (eGFR < 90 mL/min/1.73 m²). The median duration of SBS was 7 months (IQR, 3-31 months) and the mean eGFR was 103.1 ± 39.4 mL/min/1.73 m². Logistic regression modeling indicated that older age [odds ratio (OR), 1.074; 95% CI, 1.037-1.112, P < 0.001], kidney stones (OR, 4.887; 95% CI, 1.753-13.626; P = 0.002), decreased length of the small intestine (OR, 0.988; 95% CI, 0.979-0.998; P = 0.019), and prolonged duration of SBS (OR, 1.007; 95% CI, 1.001-1.013; P = 0.046) were significant risk factors for renal impairment. This is the largest study that has specifically explored the risk factors for renal impairment in a large cohort of adults with SBS. The present study showed that renal function should be closely monitored during treatment, and patients should be given prophylactic interventions if necessary. This retrospective study is a part of clinical study NCT03277014, registered in ClinicalTrials.gov PRS. And the PRS URL is http://register.clinicaltrials.gov.

How the Cluster-randomized Trial "Works"

Cluster-randomized trials (CRTs) are able to address research questions that randomized controlled trials (RCTs) of individual patients cannot answer. Of great interest for infectious disease physicians and infection control practitioners are research questions relating to the impact of interventions on infectious disease dynamics at the whole-of-population level. However, there are important conceptual differences between CRTs and RCTs relating to design, analysis, and inference. These differences can be illustrated by the adage "peas in a pod." Does the question of interest relate to the "peas" (the individual patients) or the "pods" (the clusters)? Several examples of recent CRTs of community and intensive care unit infection prevention interventions are used to illustrate these key concepts. Examples of differences between the results of RCTs and CRTs on the same topic are given.

Cost-effectiveness of selective digestive decontamination (SDD) versus selective oropharyngeal decontamination (SOD) in intensive care units with low levels of antimicrobial resistance: an individual patient data meta-analysis

OBJECTIVE

To determine the cost-effectiveness of selective digestive decontamination (SDD) as compared to selective oropharyngeal decontamination (SOD) in intensive care units (ICUs) with low levels of antimicrobial resistance.

DESIGN

Post-hoc analysis of a previously performed individual patient data meta-analysis of two cluster-randomised cross-over trials.

SETTING

24 ICUs in the Netherlands.

PARTICIPANTS

12 952 ICU patients who were treated with ≥1 dose of SDD (n=6720) or SOD (n=6232).

INTERVENTIONS

SDD versus SOD.

PRIMARY AND SECONDARY OUTCOME MEASURES

The incremental cost-effectiveness ratio (ICER; ie, costs to prevent one in-hospital death) was calculated by comparing differences in direct healthcare costs and in-hospital mortality of patients treated with SDD versus SOD. A willingness-to-pay curve was plotted to reflect the probability of cost-effectiveness of SDD for a range of different values of maximum costs per prevented in-hospital death.

RESULTS

The ICER resulting from the fixed-effect meta-analysis, adjusted for clustering and differences in baseline characteristics, showed that SDD significantly reduced in-hospital mortality (adjusted absolute risk reduction 0.0195, 95% CI 0.0050 to 0.0338) with no difference in costs (adjusted cost difference €62 in favour of SDD, 95% CI -€1079 to €935). Thus, SDD yielded significantly lower in-hospital mortality and comparable costs as compared with SOD. At a willingness-to-pay value of €33 633 per one prevented in-hospital death, SDD had a probability of 90.0% to be cost-effective as compared with SOD.

CONCLUSION

In Dutch ICUs, SDD has a very high probability of cost-effectiveness as compared to SOD. These data support the implementation of SDD in settings with low levels of antimicrobial resistance.

Comprehensive preoperative regime of selective gut decontamination in combination with probiotics, and smectite for reducing endotoxemia and cytokine activation during cardiopulmonary bypass: A pilot randomized, controlled trial

BACKGROUND

Both selective digestive decontamination (SDD) and probiotics have been reported to reduce endotoxemia. However, the available results are conflicting and few studies have investigated the combined effect of SDD and probiotics. This study aimed to examine the effectiveness of a comprehensive preoperative regimen of SDD in combination with probiotics and smectite on perioperative endotoxemia and cytokine activation in patients who underwent elective cardiac surgery with cardiopulmonary bypass (CPB) in a pilot, prospective, randomized, controlled trial.

METHODS

Patients who underwent elective Aortic Valve Replacement or Mitral Valve Replacement surgery from July 2010 to March 2015 were included. In total, 30 eligible patients were randomly assigned to receive either the comprehensive preoperative regimen (n = 15) (a combination of preoperative SDD, probiotics, and smectite) or the control group (n = 15) who did not receive this treatment. The levels of endotoxin, IL-6, and procalcitonin were measured at the time before anesthesia induction, immediately after cardiopulmonary bypass (CPB), 24 hours after CPB, and 48 hours after CPB. The primary outcomes were changes in endotoxin, IL-6, and procalcitonin concentrations after CPB.

RESULTS

The mean levels of change in endotoxin levels after CPB in patients receiving the comprehensive preoperative regimen was marginally significantly lower than those in control group (F = 4.0, P = .0552) but was not significantly different for procalcitonin (F = .14, P = .7134). An interaction between group and time for IL-6 was identified (F = 4.35, P = .0231). The increase in IL-6 concentration immediately after CPB in the comprehensive preoperative group was significantly lower than that in the control group (P = .0112). The changes in IL-6 concentration at 24 hours and 48 hours after CPB were not significant between the comprehensive preoperative group and control group.

CONCLUSION

The present pilot, prospective, randomized, controlled study in patients undergoing cardiac surgery with CPB demonstrated that 3 days of a comprehensive preoperative regime of SDD in combination with probiotics and smectite may reduce the endotoxin and IL-6 levels after CPB compared with the control group.

Unusually High Incidences of Pseudomonas Bacteremias Within Topical Polymyxin-Based Decolonization Studies of Mechanically Ventilated Patients: Benchmarking the Literature

Background

Topical polymyxin (PM)–based regimens to decolonize patients receiving prolonged mechanical ventilation (MV) have been widely studied. However, paradoxical bacteremia incidences remain unexplained.

Methods

The literature was searched for studies of topical PM–based regimens used to decontaminate MV patients reporting incidences of overall and Pseudomonas bacteremia data. In addition, observational groups without any intervention and trials of various interventions other than topical PM (non-PM studies) served to provide external benchmarks and additional points of reference, respectively. The bacteremia incidences were extracted from the control and intervention (component) groups of these studies and compared with metaregression using generalized estimating equation methods.

Results

The summary odds ratio derived from studies of topical PM–based interventions against overall bacteremia was 0.60 (95% confidence interval [CI], 0.53–0.69). Benchmark incidences per 100 MV patients for overall (mean, 8.9%; 95% CI, 6.9% to 10.9%) and Pseudomonas (mean, 0.7%; 95% CI, 0.5% to 1.1%) bacteremia were derived from 16 observational studies. By contrast, among 17 studies of topical PM, the mean incidences among control groups for overall (mean, 15.3%; 95% CI, 11.5% to 20.3%) and Pseudomonas (mean, 1.6%; 95% CI, 0.9% to 3.1%) bacteremia were both higher, whereas these incidences in the intervention groups for both topical PM and non-PM studies were in each case more similar to the respective benchmarks. These paradoxical incidences cannot readily be explained in metaregression models.

Conclusions

Paradoxically, despite an apparent prevention effect of topical PM–based methods against bacteremia overall, the incidences of Pseudomonas bacteremia within the component groups of these studies are unusually high vs literature-derived benchmarks.

Efficacy of selective digestive decontamination in patients with multiple myeloma undergoing high-dose chemotherapy and autologous stem cell transplantation

Selective digestive decontamination (SDD) with the oral, non-absorbable antimicrobial substances gentamicin, vancomycin and amphotericin B was optionally used at our institution to reduce the risk of gastrointestinal tract derived infections in multiple myeloma (MM) patients undergoing high-dose chemotherapy with subsequent autologous stem cell transplantation (HDCT/ASCT). The majority of patients received sulfamethoxazole-trimethoprim as pneumocystis pneumonia prophylaxis. From 203 patients receiving their first HDCT/ASCT between 2009 and 2015, we compared retrospectively 90 patients receiving SDD to 113 patients not receiving SDD. The administration of SDD was associated with a reduction of bacterial infections after HDCT/ASCT (overall: 8% versus 24%, p = .002; gram-negative pathogens: 1% versus 11%, p = .006) and less use of systemic antibiotics (62% versus 77%, p = .022). Omission of SDD was an independent risk factor for developing neutropenic fever and bloodstream infections. SDD could be an option to reduce bacterial infections in patients undergoing HDCT/ASCT that needs to be tested in prospective trials.

Incidences of Pseudomonas aeruginosa-Associated Ventilator-Associated Pneumonia within Studies of Respiratory Tract Applications of Polymyxin: Testing the Stoutenbeek Concurrency Postulates

Regimens containing topical polymyxin appear highly effective at preventing ventilator-associated pneumonia (VAP) overall and, more so, VAP caused by Gram-negative bacteria. However, Stoutenbeek's postulates that VAP incidences within studies of topical antibiotics depend on the context of whether the component (control and intervention) groups of each study were concurrent versus nonconcurrent remain untested. The literature was searched for concurrent control (CC) versus nonconcurrent control (NCC) designed studies of respiratory tract applications of topical polymyxin to mechanically ventilated (MV) patients that reported incidences of Pseudomonas-associated ventilator-associated pneumonia (PsVAP). Studies of various interventions other than topical polymyxin (nonpolymyxin studies) served to provide additional points of reference. The PsVAP incidences within the component groups of all studies were benchmarked against groups from observational studies. This was undertaken by meta-regression using generalized estimating equation methods. Dot plots, caterpillar plots, and funnel plots enable visual benchmarking. The PsVAP benchmark (and 95% confidence interval [CI]) derived from 102 observational groups is 4.6% (4.0 to 5.3%). In contrast, the mean PsVAP within NCC polymyxin intervention groups (1.6%; CI, 1.0 to 4.5%) is lower than that of all other component group categories. The mean PsVAP within CC polymyxin control groups (9.9%; CI, 7.6 to 12.8%) is higher than that of all other component group categories. The PsVAP incidences of control and intervention groups of studies of respiratory tract applications of polymyxin are dependent on whether the groups were within a concurrent versus nonconcurrent study. Stoutenbeek's concurrency postulates are validated.

Impact of selective digestive decontamination without systemic antibiotics in a major heart surgery intensive care unit

PURPOSE

The incidence density of ventilator-associated pneumonia (VAP) is higher in patients undergoing major heart surgery than in other populations, despite the introduction of bundles of preventive measures, because many risk factors are not amenable to intervention. Selective digestive decontamination (SDD) has been shown to be efficacious for decreasing the frequency of VAP, although it has not been incorporated into the routine of most intensive care units. The objective of our study was to evaluate the efficacy of SDD without parenteral antibiotics for preventing VAP in a major heart surgery intensive care unit.

METHODS

We compared the incidence of VAP before the introduction of SDD (17 months) and during the 17 months after the introduction of SDD and examined its ecologic influence.

RESULTS

The rates of VAP in the overall population before and during the intervention were 16.26/1000 days and 6.80 episodes/1000 days of mechanical ventilation, respectively (P = .01). The rates of VAP in the 173 patients remaining under mechanical ventilation > 48 hours after surgery were, respectively, 25.85/1000 days of mechanical ventilation versus 12.06 episodes/1000 days of mechanical ventilation (P = .04). We found a significant reduction in the number of patients with multidrug-resistant microorganisms (P = .01) in the second period of the study.

CONCLUSIONS

Our study shows that SDD without parenteral antibiotics can reduce the incidence of VAP in high-risk patients after major heart surgery, with no significant ecologic influence.

Unusually High Incidences of Staphylococcus aureus Infection within Studies of Ventilator Associated Pneumonia Prevention Using Topical Antibiotics: Benchmarking the Evidence Base

Selective digestive decontamination (SDD, topical antibiotic regimens applied to the respiratory tract) appears effective for preventing ventilator associated pneumonia (VAP) in intensive care unit (ICU) patients. However, potential contextual effects of SDD on Staphylococcus aureus infections in the ICU remain unclear. The S. aureus ventilator associated pneumonia (S. aureus VAP), VAP overall and S. aureus bacteremia incidences within component (control and intervention) groups within 27 SDD studies were benchmarked against 115 observational groups. Component groups from 66 studies of various interventions other than SDD provided additional points of reference. In 27 SDD study control groups, the mean S. aureus VAP incidence is 9.6% (95% CI; 6.9–13.2) versus a benchmark derived from 115 observational groups being 4.8% (95% CI; 4.2–5.6). In nine SDD study control groups the mean S. aureus bacteremia incidence is 3.8% (95% CI; 2.1–5.7) versus a benchmark derived from 10 observational groups being 2.1% (95% CI; 1.1–4.1). The incidences of S. aureus VAP and S. aureus bacteremia within the control groups of SDD studies are each higher than literature derived benchmarks. Paradoxically, within the SDD intervention groups, the incidences of both S. aureus VAP and VAP overall are more similar to the benchmarks.

Characterization of Enterococcus Isolates Colonizing the Intestinal Tract of Intensive Care Unit Patients Receiving Selective Digestive Decontamination

Enterococci have emerged as important opportunistic pathogens in intensive care units (ICUs). In this study, enterococcal population size and Enterococcus isolates colonizing the intestinal tract of ICU patients receiving Selective Digestive Decontamination (SDD) were investigated. All nine patients included in the study showed substantial shifts in the enterococcal 16S rRNA gene copy number in the gut microbiota during the hospitalization period. Furthermore, 41 Enterococcus spp. strains were isolated and characterized from these patients at different time points during and after ICU hospitalization, including E. faecalis (n = 13), E. faecium (n = 23), and five isolates that could not unequivocally assigned to a specific species (E. sp. n = 5) Multi locus sequence typing revealed a high prevalence of ST 6 in E. faecalis isolates (46%) and ST 117 in E. faecium (52%). Furthermore, antibiotic resistance phenotypes, including macrolide and vancomycin resistance, as well as virulence factor-encoding genes [asa1, esp-fm, esp-fs, hyl, and cyl (B)] were investigated in all isolates. Resistance to ampicillin and tetracycline was observed in 25 (61%) and 19 (46%) isolates, respectively. Furthermore, 30 out of 41 isolates harbored the erm (B) gene, mainly present in E. faecium isolates (78%). The most prevalent virulence genes were asa1 in E. faecalis (54%) and esp (esp-fm, 74%; esp-fs, 39%). Six out of nine patients developed nosocomial enterococcal infections, however, corresponding clinical isolates were unfortunately not available for further analysis. Our results show that multiple Enterococcus species, carrying several antibiotic resistance and virulence genes, occurred simultaneously in patients receiving SDD therapy, with varying prevalence dynamics over time. Furthermore, simultaneous presence and/or replacement of E. faecium STs was observed-, reinforcing the importance of screening multiple isolates to comprehensively characterize enterococcal diversity in ICU patients.

Multidrug-resistant bacteria in hematology patients: emerging threats

Multidrug-resistant (MDR) bacteria, particularly Gram negatives, such as Enterobacteriaceae resistant to third-generation cephalosporins or carbapenems and MDR Pseudomonas aeruginosa, are increasingly frequent in hematology patients. The prevalence of different resistant species varies significantly between centers. Thus, the knowledge of local epidemiology is mandatory for deciding the most appr-opriate management protocols. In the era of increasing antibiotic resistance, empirical therapy of febrile neutropenia should be individualized. A de-escalation approach is recommended in case of severe clinical presentation in patients who are at high risk for infection with a resistant strain. Targeted therapy of an MDR Gram negative usually calls for a combination treatment, although no large randomized trials exist in this setting. Infection control measures are the cornerstone of limiting the spread of MDR pathogens in hematology units.

Selective oropharyngeal decontamination versus selective digestive decontamination in critically ill patients: a meta-analysis of randomized controlled trials

BACKGROUND

Selective digestive decontamination (SDD) and selective oropharyngeal decontamination (SOD) are associated with reduced mortality and infection rates among patients in intensive care units (ICUs); however, whether SOD has a superior effect than SDD remains uncertain. Hence, we conducted a meta-analysis of randomized controlled trials (RCTs) to compare SOD with SDD in terms of clinical outcomes and antimicrobial resistance rates in patients who were critically ill.

METHODS

RCTs published in PubMed, Embase, and Web of Science were systematically reviewed to compare the effects of SOD and SDD in patients who were critically ill. Outcomes included day-28 mortality, length of ICU stay, length of hospital stay, duration of mechanical ventilation, ICU-acquired bacteremia, and prevalence of antibiotic-resistant Gram-negative bacteria. Results were expressed as risk ratio (RR) with 95% confidence intervals (CIs), and weighted mean differences (WMDs) with 95% CIs. Pooled estimates were performed using a fixed-effects model or random-effects model, depending on the heterogeneity among studies.

RESULTS

A total of four RCTs involving 23,822 patients met the inclusion criteria and were included in this meta-analysis. Among patients whose admitting specialty was surgery, cardiothoracic surgery (57.3%) and neurosurgery (29.7%) were the two main types of surgery being performed. Pooled results showed that SOD had similar effects as SDD in day-28 mortality (RR = 1.03; 95% CI: 0.98, 1.08; P = 0.253), length of ICU stay (WMD = 0.00 days; 95% CI: -0.2, 0.2; P = 1.00), length of hospital stay (WMD = 0.00 days; 95% CI: -0.65, 0.65; P = 1.00), and duration of mechanical ventilation (WMD =1.01 days; 95% CI: -0.01, 2.02; P = 0.053). On the other hand, compared with SOD, SDD had a lower day-28 mortality in surgical patients (RR =1.11; 95% CI: 1.00, 1.22; P = 0.050), lower incidence of ICU-acquired bacteremia (RR = 1.38; 95% CI: 1.24, 1.54; P = 0.000), and lower rectal carriage of aminoglycosides (RR = 2.08; 95% CI: 1.68, 2.58; P = 0.000), ciprofloxacin-resistant Gram-negative bacteria (RR = 1.84; 95% CI: 1.48, 2.29; P = 0.000), and respiratory carriage of third-generation cephalosporin-resistant Gram-negative bacteria (RR = 2.50; 95% CI: 1.78, 3.5; P = 0.000).

CONCLUSION

SOD has similar effects as SDD in clinical outcomes, but has higher incidence of ICU-acquired bacteremia, and higher carriage of antibiotic-resistant Gram-negative bacteria. However, due to the high cost of SDD and the increased risk of development of antibiotic resistance with the widespread use of cephalosporins in SDD, we would recommend SOD as prophylactic antibiotic regimens in patients in the ICU. More well-designed, large-scale RCTs are needed to confirm our findings.

A comparative study of the use of selective digestive decontamination prophylaxis in living-donor liver transplant recipients

INTRODUCTION

Bacterial infections are major causes of early morbidity and mortality after liver transplantation. Selective digestive decontamination (SDD) can be used pre-operatively for living-donor liver transplant (LD-LT), but its role in this setting remains controversial.

METHODS

To evaluate this strategy, we retrospectively analyzed a cohort of consecutive LD-LTs performed in our center from March 2007 to February 2011 and compared the incidence and nature of early infectious complications, length of intensive care unit stay and hospitalization, antibiotic use, and emergence of resistant bacteria in patients with or without SDD prophylaxis.

RESULTS

Of 148 LD-LTs in the study period, 111 received SDD prophylaxis while 37 did not. In a multivariate model, the independent factors associated with an increased risk of early post-transplant infections were length of postoperative mechanical ventilation (for every additional day odds ratio [OR] = 2.37, 95% confidence interval [CI] 1.4-4.0; P = 0.002), and choledochojejunostomy (OR = 4.5, 95% CI 1.95-10.5; P < 0.001). Use of SDD did not affect the rate or distribution of infectious complications, duration of hospitalization, antibiotic use, or acquisition of resistant bacteria (OR = 3.52, 95% CI 0.43-15.17; P = 0.376).

CONCLUSION

In conclusion, the use of SDD prophylaxis in LD-LT was not beneficial and should be avoided, as it offers no advantage and could potentiate the emergence of multidrug-resistant organisms.

Probiotic/synbiotic therapy for treating critically ill patients from a gut microbiota perspective

The gut is an important target organ for stress caused by severe insults such as sepsis, trauma, burn, shock, bleeding and infection. Severe insult to the gut is considered to have an important role in promoting infectious complications and multiple organ dysfunction syndrome. These are sequelae of interactions between deteriorated intestinal epithelium, the immune system and commensal bacteria. The gut is the "motor" of multiple organ failure, and now it is recognized that gut dysfunction is a causative factor in disease progression. The gut flora and environment are significantly altered in critically ill patients, and the number of obligate anaerobes is associated with prognosis. Synbiotic therapy is a combination of probiotics and prebiotics. Probiotic, prebiotic and synbiotic treatment has been shown to be a promising therapy to maintain and repair the gut microbiota and gut environment. In the critically ill, such as major abdominal surgery, trauma and ICU patients, synbiotic therapy has been shown to significantly reduce septic complications. Further basic and clinical research would clarify the underlying mechanisms of the therapeutic effect of probiotic/synbiotic treatment and define the appropriate conditions for use.

Opinion: the clinical use of selective digestive decontamination

Several recent meta-analyses have shown that the use of SDD can reduce the occurrence of nosocomial pneumonia among ventilated patients in the intensive care unit (ICU) setting. However, the use of SDD has also been demonstrated to increase subsequent patient colonization and infection with antibiotic-resistant bacteria, particularly Gram-positive cocci. Therefore, the routine use of SDD cannot be advocated at the present time. The mortality benefit of SDD appears to occur in surgical/trauma patients, and to be associated primarily with the administration of parenteral antibiotics. This is already an accepted practice in most patients during the perioperative period (eg prophylactic parenteral antibiotics for 24 h). Prolonged decontamination of the aerodigestive tract with topical antimicrobials does not appear to influence outcome, and should not be routinely employed.