Prevention of ventilator-associated pneumonia in intensive care units: an international online survey

Our target group was physicians working in ICUs. An ICU was defined as an unit meeting all the following criteria: provides facilities for invasive mechanical ventilation, and pump-controlled administration of infusion, functions 24 hours a day and 7 days a week, and there is at least one doctor immediately available at all times to deal with emergencies.

We developed a questionnaire with 3 parts: 1) Characteristics of the respondent and her/his ICU, 2) VAP prevention practices (clinical, and measurement). For clinical practices we focused on the top 5 clinical components of the European VAP care bundle [10] and added a commonly recommended practice (head of bed elevation) [5]. For measurement, we included questions on measurement of process (compliance to prevention practices, average duration of intubation) and outcomes (measurement of VAP, definitions used for data collection – European, [18] or American, [19] and the ability to report selected indicators. 3) attitudes as regards the implementation of a data collection system, using a 5 point-Likert scale (1: strongly agree, 5: strongly disagree) [13, 21]. The questionnaire was kept very short to improve participation. It was first developed and pre-tested in English, then translated into German, Italian, Spanish, Portuguese and French by intensive care doctors and/or infection control practitioners, native speakers in the targeted language. Each translation had to be independently checked by at least another native speaker doctor. We used Limesurvey 2.0, an open source web survey application, to collect the data [22]. Participation was anonymous.

The questionnaire was available online from April 1 to September 1, 2012. It was endorsed by the European Society of Intensive Care Medicine (ESICM), posted on their website, and the link e-mailed to all its members. We contacted national ESICM representatives and key opinion leaders and requested their support in disseminating the survey in their country. The survey was endorsed by national ICU societies in Austria, France, Belgium, the Netherlands, Italy, and Greece. It was e-mailed to all subscribers of REMI (Revista Electronica de Medicina Intensiva), [23] an electronic newsletter on intensive care medicine in Spanish distributed in Spain, Portugal, and Latin America.

Descriptive statistics were used to characterize the study sample. Using total country population (2012 United Nations estimates [24]) as the weight, we computed weighted European estimates including all countries which provided at least 10 completed replies. This arbitrary threshold was chosen as a compromise between the number of countries included in the European estimates, and precision of the estimation. Statistical software STATA 10 was used for the analyses (svy command for survey data for weighted estimates). Replies from the remaining countries, both European and non European, were simply pooled together. We choose to present uncommented, detailed country-specific results as Additional file 1, for use by national stakeholders.

This is, to our knowledge, the first international survey assessing VAP prevention practices – (clinical, and measurement) – among ICUs doctors. Participation was large, and almost two thirds of respondents reported the existence of written VAP prevention guidelines in their ICU - pointing out the interest in, and awareness of the problem. If we combine the good clinical practice, AND measuring compliance to this practice at least once a year (a very pragmatic objective), this was reported by 57% (hand hygiene), 29% (daily interruption of sedation) and 26% (oral care with chlorhexidine) of the participants to this survey (European estimates). Interestingly, “head of bed elevation” - a practice ranked very low in the “European care bundle” because it was perceived as difficult to implement - was mentioned by 96% of the respondents; this clinical practice was known by 85% of European nurses participating in a knowledge test about VAP prevention practices [25].

As regards measurement of outcomes, European estimates show that only 54% count and record the number of VAP on a routine basis; and only 20% were able to provide data for their ICU on the main indicator used to monitor VAP - (VAP/1000 intubation-days). In contrast with these low proportions 93% agreed that “monitoring of VAP-related measures stimulates quality improvement” and 84% said they were willing to implement, or support, a VAP data collection system. They expressed some distrust as regards the data (46% agreed with the statement “clinical diagnosis of VAP is difficult; this makes measurement unreliable”), on the other hand, only 50% were aware of a standardized case definition for VAP recording in their ICU; and only 45% understood the difference between a definition of VAP for recording, and a diagnosis of VAP. Overall, 95% of respondents agreed that reliable data would facilitate the implementation of a measurement system.

These European estimates mask large difference between countries. For example oral care with chlorhexidine was reported by 55% (139/251) of the respondents in France, and by 94% (276/293) in Spain. Respondents saying yes to the question “in my ICU, we count and record VAP on a routine basis” were 50% (57/115) in the UK, and 74% (218/293) in Spain. Daily sedation vacation and weaning protocol were reported by 81% (93/115) in the UK, and by 35% (66/187) in Italy (see country-specific data, as Additional file 1).

Results from the 449 respondents not included in the European estimates are surprisingly similar to those of the European estimates.

This survey has several limitations. First, we cannot claim that participants represent a random sample of ICU clinicians in Europe nor in their own country. Some categories of ICU doctors are likely to be overrepresented, such as members of ICU national, or international societies. These might be better informed, and apply VAP prevention guidelines more than the average clinician. The list of VAP prevention measures we used as a reference for good practices guidelines [10] could be criticized on several grounds, e.g. it does not include subglottic secretions drainage [26]. Our dissemination strategy obviously worked better in some countries than others. Another limitation is that some questions in the questionnaire apply to the individual physician and others to the ICU (“in my ICU, care for intubated patients includes…) but the online questionnaire did not include questions allowing for the identification of the ICU, in order to preserve the anonymity of the respondents.

Respondents not included in the European estimates represent a very heterogeneous population with no clear geographical basis. We nevertheless considered it worthwhile to pool these results, because together these doctors are responsible for a large number of patients, and these data have identified weaknesses broadly similar to those observed in the European estimates.

Clearly, it cannot be concluded from a doctor’s reporting of a clinical practice in her/his setting, that this practice is used all the time for every patient who needs it: self-reports mainly provide information regarding clinicians’ knowledge of guideline recommendations, but they are subject to bias – overestimation – and should not be used as the sole measure of guideline adherence [27]. Measuring compliance to guidelines at local level once a year appears as an absolute minimum. We did not ask details on the methods used to measure compliance. This is not necessarily easy, for instance detailed guidelines exist for measuring compliance to hand hygiene recommendations; [28] and oral care in ventilated patients is a complex procedure that might require a check list [29].

It was not among the objectives of this survey to collect data on VAP incidence rate in ICUs – there are much better sources for this – e.g. surveillance data for Europe [1]. Rather we wanted to investigate the knowledge doctors had of the rates in their units. However data provided on VAP rates (not shown) are in the expected range as reported in surveillance networks [1], giving some validity to our results.

The large participation to this survey reflects the interest of the ICU community in the issue of VAP prevention. To the extent that the selection bias, and the reporting bias in our results lead to overestimating VAP prevention practices in ICUs, weaknesses identified appear robust enough as to support targeted interventions for improvement. The priority for improving care of intubated patients is promoting the clinical practices with the lowest reported use (daily sedation vacation, and weaning protocols, oral care with chlorhexidine, and no ventilatory circuit change unless specifically indicated). Improving knowledge of clinical guidelines is far from sufficient to improve practices [25, 30] but it is a prerequisite. ICUs doctors overwhelmingly agree that monitoring of VAP-related measures stimulates quality improvement but very few do it, although most are willing to do it. They could be helped to do so by learning how to produce reliable data (standardized case-definitions, methods for measuring compliance) with real-time feed-back at the ICU level; so that clinical staff could monitor their own trends over time. A compromise needs to be found between time-consuming data collection, and usefulness of data. Additional resources (human resources, information technology) might help, but some very simple measures can be implemented with minimal input, e.g. in some ICUs a panel with the number of days since last ICU-acquired infection (including VAP) is displayed on the board and updated daily (personal observations in Scotland, MLL). This study did not consider the issue of surveillance and reporting of outcome indicators at regional or national level, nor the merits (or otherwise) of evaluation of performance and feed-back, based on benchmarking (e.g. comparisons between units). Specific priorities might differ between countries.