The predictive validity for mortality of driving pressure and mechanical power of ventilation

Background: Outcome prediction in invasively ventilated ICU patients remains challenging. Driving pressure (ΔP) and mechanical power of ventilation (MP) are associated with outcomes like mortality. The objective of this study was to assess the predictive validity for mortality of ΔP and MP at 24h after start of invasive ventilation. Methods: Posthoc analysis of MARS, a large observational study in two Dutch ICUs. Patients having received invasive ventilation >24h were selected. The primary outcome was 90–day mortality. The predictive validity of ΔP and MP was measured as incremental 90–day mortality beyond that predicted by the Acute Physiology, Age and Chronic Health Evaluation (APACHE) IV score or the Simplified Acute Physiology Score (SAPS) II. Results: A total of 839 patients were included; 90–day mortality was 42%. ΔP (OR for 1 cm H2O increase in ΔP, 1.05 [CI 1.03–1.08] p Conclusions: In this cohort of invasively ventilated ICU patients, ΔP and MP at 24h were associated with 90–day mortality. However, they have no predictive validity beyond that of the APACHE IV score and the SAPS II.