A consensus of European experts on the definition of ventilator-associated pneumonia recurrences obtained by the Delphi method: the RECUVAP study.

Background: There are recognized diagnostic criteria for a first ventilator-associated pneumonia (VAP) episode, but not for recurrences. Many randomized clinical trials (RCTs) have used the recurrence of VAP as a criterion for efficacy evaluation. Still, the different definitions used in RCTs make it difficult to compare studies. We aimed to develop a consensual definition of VAP recurrences and of the various types of VAP recurrences.

Methods: Thirty-six European experts constituting a multidisciplinary group of physicians (critical care, infectious diseases, microbiology) with special interest in the management of VAP were polled using the Delphi methodology.

Results: After the completion of four iterations of the DELPHI method, 94% of experts agreed that the diagnostic criteria for a first VAP episode could also be used for recurrences, except for the radiological criterion, which not all the experts considered to be mandatory. Consensus was also reached regarding the definition of four distinct entities: relapse, persistent VAP, superinfection, and new-pathogen VAP. For relapse and persistent VAP, bacteriological findings were identical for different VAP episodes, whereas they differed for superinfection and new-pathogen VAP. The distinction between relapse and persistent VAP, and between superinfection and new-pathogen VAP depended on the timing of antibiotic treatment (before or after 48-72 h after the end of antibiotic therapy) and the clinical course. Microbiological criteria were proposed to facilitate the diagnosis of persistent VAP.

Conclusion: This consensus by European experts proposes four different VAP recurrence entities which should facilitate the harmonization of recurrence criteria for clinical practice and future studies.