Rapid Responses to:
|
|
Rapid Responses: Rapid Responses published:
-
![[Read Rapid Response]](/icons/misc/sectionDOWN.gif)
Antiseptics (rather than antibiotics) should be used for decontamination to prevent ventilator associated pneumonia
- Paula J Whittaker, Marko Petrovic (25 April 2007)
-
Oral chlorhexidine better than oropharyngeal topical antibiotics in the prevention of pneumonia during mechanical ventilation. A message hard to swallow.
- Luciano Silvestri, Hendrick H.K. van Saene, Miguel A. de la Cal (21 November 2007)
-
Considering antiseptic oral decontamination to reduce ventilator-associated pneumonia
- Ee Yuee Chan, Annie Ruest, and Maureen O. Meade (13 December 2007)
|
|
|||
|
Paula J Whittaker, Specialist Registrar Public Health Greater Manchester Health Protection Unit, Peel House, Eccles, Manchester, M30 0NJ, Marko Petrovic
Send response to journal:
|
This review looked at an important and contentious topic in the prevention of ventilator associated pneumonia. An important finding was that the results failed to show any clear benefit for the use of antibiotics rather than antiseptics for oral decontamination to prevent ventilator associated pneumonia. If decontamination is to be performed then antiseptics should be chosen rather than antibiotics. This follows from the principle of first doing no harm, both from the perspective of the individual patient and the wider public health implications of decontamination. When applied to populations with low incidence of antibiotic resistance and hospital-acquired infections such as C. difficile, antibiotic oral decontamination might be justified, but it is less justifiable in the NHS where there are high and increasing levels of antibiotic resistance and hospital-acquired infection, which has led to a focus on restricting the use of antibiotics. A very important implication of the findings was that a reduction in ventilator associated pneumonia might not necessarily lead to reduction in mortality or length of time spent ventilated or in intensive care, and so may not be clinically significant. This suggests the possibility that those cases of ventilator associated pneumonia prevented by decontamination were due to contamination rather than clinically significant pneumonia. The authors understandably call for more evidence for the prevention of ventilation association pneumonia using oral antibiotic decontamination, but we feel that more data will not clarify the issue unless the diagnostic criteria for ventilated association pneumonia is universally agreed. Competing interests: None declared |
|||
|
|
|||
|
Luciano Silvestri, Head, Department of Emergency, Unit of Anaesthesia and Intensive Care Presidio Ospedaliero di Gorizia, 34170 Gorizia, Italy, Hendrick H.K. van Saene, Miguel A. de la Cal
Send response to journal:
|
Dear Editor, We read with interest the systematic review and meta-analysis by Chan et al. on the impact of oral decontamination for the prevention of pneumonia in mechanically ventilated adults patients (1). The analysis demonstrated that oropharyngeal decontamination with disinfectants was superior to that with antibiotics. We believe that this surprising result may be due to an inaccurate selection of trials and data extraction. Firstly, although the authors stated that trials on selective decontamination of the digestive tract (SDD) were excluded, three out of four randomised controlled trials (RCTs) included in the analysis of oropharyngeal antibiotics were actually SDD trials. Therefore, those trials should be deleted from the analysis. Conversely, if those trials should not have been classified as SDD trials, then the authors missed five more trials employing only oropharyngeal topical antibiotics. A meta- analysis of these eight trials of oral decontamination with antibiotics shows a significant pneumonia reduction (common odds ratio 0.16; 95%CI 0.10 - 0.26) (L. Silvestri, personal communication). Additionally, the authors felt uncomfortable with the inclusion of the iseganan study because the use of iseganan in solution instead of paste failed to decontaminate the oropharynx, as there were no differences in reductions in Gram-negative organisms and Staphylococcus aureus between test and control groups (2). Secondly, more than half the population of the chlorhexidine meta- analysis were cardiac surgery patients included in two RCTs (3). However, those studies reported the incidence of nosocomial pneumonia not that of VAP, as the duration of ventilation was 12 hours on average. Therefore, those studies should not be included in a meta-analysis with the end point of VAP. Additionally, both control and test groups in those studies received parenteral cefuroxime or vancomycin as peri-operative prophylaxis; this antibiotic effect may have reduced the incidence of primary endogenous pneumonia due to community microorganisms. Moreover, a methodological flaw of this review is the inclusion of one study comprising episodes of infection instead of patients (3). Hence, an accurate inclusion of chlorhexidine studies would have given a not significant reduction in VAP, confirming the results of two previous meta- analyses on the same topic (4, 5). In conclusion, we believe that the main result of this meta-analysis that oral antiseptics work better than oropharyngeal topical antibiotics in preventing VAP is not valid, as it is not supported by an appropriate trial selection and data extraction. References 1. Chan EY, Ruest A, O Meade M, Cook DJ. Oral decontamination for prevention of pneumonia in mechanically ventilated adults: systematic review and meta-analysis. BMJ 2007;334:889. 2. van Saene HK, Van Saene J, Silvestri L, de la Cal M, Sarginson R, Zandstra D. Iseganan failure due to the wrong pharmaceutical technology. Chest 2007;132:1412. 3. Silvestri L, van Saene JJ, van Saene HK, Weir I. Topical chlorhexidine and ventilator-associated pneumonia. Crit Care Med 2007;35:2468. 4. Pineda LA, Saliba RG, EL Solh AA. Effect of oral decontamination with chlorhexidine on the incidence of nosocomial pneumonia: a meta- analysis. Crit Care 2006;10:R35. 5. Chelbicki MP, Safdar N. Topical chlorhexidine for prevention of ventilator-associated pneumonia: a meta-analysis. Crit Care Med 2007;35:595-602. Competing interests: None declared |
|||
|
|
|||
|
Ee Yuee Chan, Nurse Educator Department of Nursing Services, Tan Tock Seng Hospital, Singapore 308433, Annie Ruest, and Maureen O. Meade
Send response to journal:
|
Dear Editor, We thank Dr. Silvestri and colleagues for their feedback on our work.1 Our systematic review did not show that "oral chlorhexidine is better than oropharyngeal topical antibiotics in the prevention of pneumonia during mechanical ventilation"; we found no trials directly comparing these two approaches to oropharyngeal decontamination. We conducted two distinct pooled analyses (i.e. antibiotics versus no prophylaxis and antiseptics versus no prophylaxis). Our findings suggested that antiseptic oral decontamination of mechanically ventilated adults is effective at preventing ventilator associated pneumonia. There was insufficient evidence to draw conclusions on the efficacy of oral decontamination with antibiotics due to the small number of trials available for synthesis. Our review defined selective decontamination of the digestive tract (SDD) as involving the administration of non-absorbable antibiotics orally and through a nasogastric tube, while oral decontamination is limited to the topical application of antibiotics or antiseptics.2 Hence, the randomised controlled trials (RCTs) in our review belong to the latter group. Dr. Silvestri and colleagues suggested that we missed five other antibiotic oral decontamination trials, but did not cite them, so we are unsure if they are published, or whether they were omitted because they did not meet our inclusion criteria or fulfilled an exclusion criterion. For instance, we excluded two trials because they were not truly randomised. We refer the authors to the unabridged version of our article for further information on our excluded trials.3 We included a trial using iseganan, a synthetic variant of porcine protegrin (a natural antibiotic peptide) with a broad spectrum of activity against aerobic and anaerobic gram-positive and gram-negative bacteria and yeasts.4 Silvestri et al. are uncomfortable with the inclusion of this trial, since iseganan was ineffective. The scientific foundation of systematic review methodology does not permit the selection of studies based upon their results, rather, studies are selected based upon meeting precise eligibility criteria, as this study did. Silvestri et al. are concerned about trials in which "both control and test groups" received perioperative prophylactic antibiotics. Both active and control groups received similar antibiotic cointerventions within each trial, so each trial's treatment effect reflects the intervention being tested. Finally, since we wrote to authors to confirm data or to obtain unpublished data when necessary, we used the number of patients rather than episodes of VAP as our unit of analysis. Ee Yuee Chan, Nurse Educator, Department of Nursing Services, Tan Tock Seng Hospital, Singapore. Annie Ruest, Infectious Disease Consultant, Centre Hospitalier Universitaire, de Quebec-Hotel-Dieu, Departments of Medicine and Medical Biology, Quebec, Canada. Maureen O. Meade, Associate Professor, Departments of Medicine, Clinical Epidemiology, and Biostatistics, McMaster University, Hamilton, Canada. References 1. Silvestri L, van Saene HHK, de la Cal MA. Oral chlorhexidine better than oropharyngeal topical antibiotics in the prevention of pneumonia during mechanical ventilation. A message hard to swallow. BMJ Comment. Letter (published 21 November 2007). 2. Chan EY, Ruest A, Meade MO, Cook DJ. Oral chlorhexidine for the prevention of pneumonia in mechanically ventilated adults: systematic review and meta-analysis. BMJ 2007, 334: 889-93. 3. Chan EY, Ruest A, Meade MO, Cook DJ. Oral chlorhexidine for the prevention of pneumonia in mechanically ventilated adults: systematic review and meta-analysis. BMJ doi.10.1136/bmj.39136.528160.BE (published 26 March 2007). 4. Kollef M, Pittet D, Sanchez Garcia M, Chastre J et al. A randomized double-blind trial of iseganan in prevention of ventilator- associated pneumonia. Am Respir Crit Care Med 2006,173: 91-7. Competing interests: None declared |
|||