Ventilator-Associated Pneumonia (VAP) is a bacterial respiratory infection that patients in the Intensive Care Unit (ICU) often get when they cannot breathe for themselves and require mechanical ventilation. It is linked to higher chances of death, a longer stay in the hospital, higher costs, and the use of more antibiotics.

Options to help prevent or treat this disease are in development and will require evaluation in future clinical trials.

The goal of POS-VAP is to build and continuously train a network of ICUs to be prepared for doing these trials, to facilitate their execution.

Ventilator associated pneumonia (VAP) is one of the most frequent healthcare associated infections in the Intensive Care Unit (ICU) and a significant burden among ICU patients under invasive mechanical ventilation (IMV).

Several preventive and therapeutic treatment options are being developed in the field of VAP that will require evaluation in future randomized controlled trials (RCTs).

RCTs are the gold standard for evaluating medical interventions but are difficult to perform in a population at risk of, or with, VAP.

These trials are challenging since it is difficult to recruit a large enough volume of high-quality centers to achieve the required number of recruited patients, especially if the focus is on specific patient groups (e.g., VAP due to a specific pathogen), for which site selection can be even more challenging and time consuming. There is a need for a well-organized and well-trained international network of ICUs focusing on VAP research that enables efficient execution of RCTs on diagnostic, preventive and curative interventions in this population.

Through a Perpetual Observational Study (POS) we can provide quick access to a network of sites that fulfill pre-specified criteria. Additionally, the structured network of POS sites within ECRAID will maintain continuous activity to carry out observational studies in this specific field, implementing informed consent (where required), increasing quality and efficiency, and facilitating contracting.

Inclusion criteria:

• Age≥18 years
• At risk of acquiring VAP during ICU stay, defined as:
• Requiring admission or being admitted to the ICU.
• Expected or documented to be under IMV for more than 48 hours.
• Consent, either a written informed consent given by the study patient in full medical, psychological, cognitive, social or legal capacity to give an informed consent, or, if not possible, by a Legally Authorized Representative of the study patient OR any applicable locally accepted form of consent OR consent waiver allowing data collection and sharing of data according to ECRAID's principles

Exclusion Criteria:

• Death is deemed to be imminent or inevitable during this hospital admission AND one or more of the patient, substitute decision maker or attending physician are not committed to full active treatment.

All patients admitted to an ICU, who are under IMV and documented or expected to be under IMV for more than 48 hours are eligible to participate in the study

Data from this study will be used to inform future observational studies and RCTs about expected frequencies of exposures and clinical outcomes and expected recruitment rates for specific patient populations. Furthermore, the data will be used to support simulations to gain insight in the optimal design and required sample size of future RCTs as required for future embedded studies, which will be described in the appendices.