Comments
Applying mechanical ventilation and selecting ventilatory strategies in patients with acute brain injuries, especially those with lung damage, is challenging. Static (positive end-expiratory pressure) and dynamic (intratidal) changes in ventilator pressure, via complex pathways, influence cerebral arterial inflow and cerebral venous pressure and thus cerebral blood volume and intracranial pressure. In this process, the relationship between airway pressure and pleural and transalveolar pressures, heavily affected by elastance of the chest wall and lung, respectively, plays a central role. This relationship determines the extent to which a static and dynamic increase in airway pressure affects the cardiac function and venous return curves, which govern the static and dynamic arterial and central venous pressures. The integrity of cerebral autoregulation determines whether static changes in arterial pressure alter cerebral arterial inflow. Conversely, dynamic changes in arterial pressure during the breath are followed by corresponding changes in cerebral arterial inflow because of the inability of autoregulation to control rapid arterial pressure fluctuations. The flow dynamics in the jugular veins and the relationship between intracranial and sagittal sinus pressures determine whether static and dynamic changes in central venous pressure alter cerebral venous pressure. Setting the ventilator and planning strategies should be individualized and guided by the complex, interactive effects among central nervous, respiratory, and cardiovascular systems on cerebral blood volume and cerebral perfusion and intracranial pressures. Following a logical framework, clinicians may anticipate the likely effects of ventilator settings and strategies on cerebral hemodynamics, enabling a more individualized approach in setting the ventilator and planning ventilatory strategies.
Author Contributions: D.G. contributed to the conception of this work. D.G., S.T., M.B., and E.A. drafted and reviewed the manuscript. All authors critically revised the manuscript for intellectually important content and gave final approval of the version to be submitted.
A data supplement for this article is available via the Supplements tab at the top of the online article.
Artificial Intelligence Disclaimer: We used artificial intelligence technologies (free version of ChatGPT; http://chat.openai.com) strictly for grammar correction in some sentences. The brain icon appearing in Figures 2B, 4B, 6, and E3–E5 was generated using OpenArt (http://openart.ai/home).
Originally Published in Press as DOI: 10.1164/rccm.202409-1813SO on February 19, 2025
Author disclosures are available with the text of this article at www.atsjournals.org.
Related
| Comments | Post a Comment |
|---|
New User RegistrationNot Yet Registered?Benefits of Registration Include:
|
