Ventilator-associated Events in Children: Controversies and Research Needs.

Copyright © 2020 Wolters Kluwer Health, Inc. Unauthorized reproduction of this article is prohibited. The Pediatric Infectious Disease Journal • Volume 39, Number 4, April 2020 www.pidj. com | e37 H infections (HAIs) constitute a common but highly preventable event during hospitalization. Healthcareassociated pneumonia, including ventilatorassociated pneumonia (VAP), together with healthcare-associated primary bloodstream infection, represents the largest proportion of HAIs. The estimated median disabilityadjusted life years associated with healthcare-associated pneumonia was estimated to be 170 per 100,000 population by the European Center for Disease Control. VAP constitutes one of the most common HAI experienced by critically ill children and has been related to increased morbidity, length of stay, broad-spectrum antibiotic usage and cost. Despite the high burden and complications of VAP, currently, a major impediment in VAP prevention is the lack of a precise, reproducible and clinically meaningful definition. This has a significant impact on VAP surveillance, clinical management and prevention. To improve the quality of surveillance data, essential to drive local improvement and to a benchmark of quality of care, there has been an effort to improve the definition of VAP. An imaging-based VAP definition was used by US Centers for Disease Control and Prevention (CDC) for many years and widely adopted by most HAI surveillance networks, including the International Nosocomial Infection Control Consortium, as well as national databases supported by other developed and developing countries. More recently, however, this imaging-based definition has been abandoned by many HAI surveillance programs due to the subjective nature of key criteria, such as radiologic findings. Radiologic criteria for the original VAP definition included new or worsening infiltrates on a chest radiograph, a nonspecific finding that occurs in other disease processes such as atelectasis, acute respiratory disease syndrome and alveolar hemorrhage. Similarly, clinical signs and symptoms of the original VAP definition, such as fever, purulent bronchial secretions and leukocytosis, are common in critically ill patients who have noninfectious disease processes. Although other definitions have been used for VAP surveillance, such as the Clinical Pulmonary Infection Score, these definitions are also flawed because of the inclusion of criteria related to radiographic abnormalities. Because of shortcomings in the original VAP and other existing definitions, CDC introduced a broader and potentially more objective definition for ventilator-associated events (VAE) in adults. This algorithm is based on objective criteria, including the fraction of inspired oxygen (FiO 2 ), positive end-expiratory pressure (PEEP); no radiographic criteria are included. The VAE algorithm consists of 3 tiers: ventilator-associated complications (VACs), infection-related ventilator-associated complications (IVAC) and possible/probable VAP (Table 1). These categories have been used for surveillance in adult critically ill patients by CDC since 2013. Simultaneous use of VAE and VAP algorithms in critically ill adult patients has confirmed that there is poor agreement between these definitions. Both the original VAP as well as the ventilator-associated tracheitis have been misdiagnosed by VAE definition and vice versa. However, patients identified with VAE have been demonstrated to have worse outcomes than those who do not develop VAE, suggesting a degree of clinical validity. Currently, the impact of this new