The relationship between mechanical power normalized to dynamic lung compliance and weaning outcomes in mechanically ventilated patients.

Background: Prolonged mechanical ventilation is associated with an increased risk of mortality in these patients. However, there exists a significant clinical need for novel indicators that can complement traditional weaning evaluation methods and effectively guide ventilator weaning.

Objectives: To investigate the specific relationship between mechanical power normalized to dynamic lung compliance (Cdyn-MP) and weaning outcomes in patients on mechanical ventilation for more than 24 hours, as well as those who underwent a T-tube weaning strategy.

Methods: A retrospective cohort study was conducted using the Medical Information Mart for Intensive Care-IV v1.0 database (MIMIC-IV v1.0). Patients who received invasive mechanical ventilation for more than 24 hours and underwent a T-tube ventilation strategy for weaning were enrolled. Patients were divided into two groups based on their weaning outcome: weaning success and failure. Ventilation parameter data were collected every 4 hours during the first 24 hours before the first spontaneous breathing trial (SBT).

Results: Of all the 3,695 patients, 1,421 (38.5%) experienced weaning failure. Univariate logistic regression analysis revealed that the risk of weaning failure increased as the Cdyn-MP level rose (OR 1.34, 95% CI 1.31-1.38, P<0.001). After adjusting for age, body mass index, disease severity, and pre-weaning disease status, patients with high Cdyn-MP quartiles in the 4 hours prior to the SBT had a significantly greater risk of weaning failure than those with low Cdyn-MP quartiles (odds ratio 10.37, 95% CI 7.56-14.24). These findings were robust and consistent in both subgroup and sensitivity analyses.

Conclusion: The increased Cdyn-MP before SBT was independently associated with a higher risk of weaning failure in mechanically ventilated patients. Cdyn-MP has the potential to be a useful indicator for guiding the need for ventilator weaning and complementing traditional weaning evaluation methods.