VAP, VAC, IVAC and Ventilator Associated Events: The Need for Objectivity for Surveillance Streamlining Ventilator Associated Pneumonia Surveillance Methods Surveillance Cultures for Multi Drug Resistant Gram Negative B Pneumonia (Ventilator associated [VAP] and non ventilator associated Pneumonia [PNEU]) Event Ventilator Associated Pneumonia (VAP): Why is it so difficult to define? In real world practice: The diagnosis of VAP remains more an exercise in clinical integration than strict adherence to criteria.