Mechanical power (MP) could serve as a valuable parameter in clinical practice to estimate the likelihood of adverse outcomes. However, the safety thresholds for MP in mechanical ventilation remain underexplored and contentious. This study aims to investigate the association between MP and hospital mortality across varying degrees of lung disease severity, classified by Pao2/Fio2 ratios. This is a retrospective cohort study using automatically extracted data. Patients admitted to the ICU of a tertiary referral hospital in The Netherlands between 2018 and 2024 and ventilated in pressure-controlled mode were included. Logistic regression, adjusted for age, sex, Acute Physiology and Chronic Health Evaluation-IV score, and Pao2/Fio2 ratio, was used to calculate the odds ratio (OR) for all-cause in-hospital mortality. A total of 2184 patients were analyzed, with a mean age of 62.5 ± 13.8 years, of whom 1508 (70.2%) were male. The mean MP was highest in patients with the lowest Pao2/Fio2 ratios (21.5 ± 6.5 J/min) compared with those with the highest ratios (12.0 ± 3.8 J/min; p < 0.001). Adjusted analyses revealed that increased MP was associated with higher mortality (OR, 1.06; 95% CI, 1.03-1.09 per J/min increase). Similarly, MP normalized for body weight showed a stronger association with mortality (OR, 1.004; 95% CI, 1.002-1.006 per J/min/kg increase). An increase in mortality was seen when MP exceeded 16-18 J/min. Our findings demonstrate a significant association between MP and hospital mortality, even after adjusting for key confounders. Mortality increases notably when MP exceeds 16-18 J/min. Normalized MP presents an even stronger association with mortality. These results underscore the need for further research into ventilation strategies that consider MP adjustments.
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