Intra-abdominal hypertension and hypoxic respiratory failure together predict adverse outcome - A sub-analysis of a prospective cohort

Purpose: To assess whether the combination of intra-abdominal hypertension (IAH, intra-abdominal pressure >_ 12 mmHg) and hypoxic respiratory failure (HRF, PaO2/FiO2 ratio < 300 mmHg) in patients receiving invasive ventilation is an independent risk factor for 90-and 28-day mortality as well as ICU-and ventilation-free days. Methods: Mechanically ventilated patients who had blood gas analyses performed and intra-abdominal pressure measured, were included from a prospective cohort. Subgroups were defined by the absence (Group 1) or the presence of either IAH (Group 2) or HRF (Group 3) or both (Group 4). Mixed-effects regression analysis was performed. Results: Ninety-day mortality increased from 16% (Group 1, n = 50) to 30% (Group 2, n = 20) and 27% (Group 3, n = 100) to 49% (Group 4, n = 142), log-rank test p < 0.001. The combination of IAH and HRF was associated with increased 90-and 28-day mortality as well as with fewer ICU-and ventilation-free days. The association with 90-day mortality was no longer present after adjustment for independent variables. However, the association with 28-day mortality, ICU-and ventilation-free days persisted after adjusting for independent variables. Conclusions: In our sub-analysis, the combination of IAH and HRF was not independently associated with 90-day mortality but independently increased the odds of 28-day mortality, and reduced the number of ICU-and ventilation-free days. (c) 2021 Elsevier Inc. All rights reserved.