Optimising mechanical ventilation: integrating clinical needs with mechanical power reduction strategies

The study by Buiteman-Kruizinga et al. provides valuable insights into the determinants of mechanical power during mechanical ventilation [1]. The authors highlight the importance of limiting respiratory rate and peak pressures to reduce mechanical power and, potentially, ventilator-induced lung injury. We would like to discuss some aspects that merit further exploration.

First, the study suggests that reducing respiratory rate may be a viable strategy to lower mechanical power. However, the potential trade-off between reduced mechanical power and increased carbon dioxide retention remains underexplored [2]. In patients with impaired carbon dioxide clearance, such as those with chronic obstructive pulmonary disease or a metabolic acidosis, a lower respiratory rate might exacerbate hypercapnia, leading to respiratory acidosis and haemodynamic instability [3]. Future studies could investigate optimal mechanical power thresholds that balance lung protection with adequate carbon dioxide elimination.

Second, while mechanical power is linked to lung injury, its direct contribution to alveolar stress and strain was not assessed explicitly. In addition to pressure- and volume-related parameters, lung compliance plays a crucial role in determining the actual stress imposed on the lung parenchyma [4]. A stratified analysis based on compliance levels could provide a more granular understanding of how mechanical power interacts with lung mechanics, particularly in heterogeneous conditions such as acute respiratory distress syndrome.

Lastly, the study focuses primarily on short-term ICU outcomes. However, the impact of mechanical power modulation on long-term respiratory function and weaning success is unknown. Given that prolonged exposure to high mechanical power may contribute to persistent lung fibrosis or impaired ventilatory mechanics, follow-up studies assessing post-ICU pulmonary function could enhance our understanding of its clinical consequences [5].

In conclusion, while this study is an important step toward optimising mechanical ventilation strategies, addressing the interplay between mechanical power, gas exchange and long-term respiratory outcomes could further refine lung-protective ventilation strategies.