The association of ventilator mechanical power with weaning outcomes in intensive care unit patients: a narrative review

Mechanical power (MP) provides an integrated index of the mechanical properties of the respiratory system during mechanical ventilation. Increased levels of MP may identify patients who will do poorly during weaning and extubation. This literature review investigated the use of MP as a predictor of weaning outcomes in intensive care unit (ICU) patients, including a focused comparison of patients with coronavirus disease 19 (COVID-19) infections and patients with other causes of respiratory failure. A review of the literature using PubMed, Embase, MEDLINE, and Preprint identified 305 possible studies; after removal of duplicates, 219 studies were screened, and five papers were selected for analysis. A search updated in 2024 identified four additional papers to include in this review. These studies demonstrate that higher MP levels are associated with weaning failure in ICU patients and that adjustment of MP for lung-thorax compliance (LTC) improves the prediction of outcomes. One study analyzed outcomes in patients with COVID-19 infections and reported that despite having higher MPs, patients with COVID-19 had lower rates of weaning failures. This result suggests different respiratory mechanics in these patients that could complicate weaning decisions. In summary, MP can predict weaning outcomes in patients with respiratory failure requiring mechanical ventilation. However, some patients with COVID-19 infection may have unusual respiratory mechanics that may influence these associations.