Brain Monitoring During PEEP-Based Respiratory Therapy in Critically Ill Patients

Condition(s) studied

Investigational drug(s) / intervention(s)

Recruitment Maneuver: A standardized lung recruitment maneuver performed during mechanical ventilation to transiently increase airway pressure and reopen collapsed alveoli. Physiological responses are continuously monitored using multimodal neuromonitoring and hemodynamic monitoring systems.

Positive End-Expiratory Pressure Adjustment: Positive end-expiratory pressure (PEEP) levels are adjusted according to the study protocol during mechanical ventilation. Cerebral electrophysiological activity, cerebral blood flow, systemic hemodynamics, and respiratory parameters are continuously recorded during PEEP modifications.

Study summary

Mechanical ventilation is commonly used in critically ill patients with acute brain injury. Positive end-expiratory pressure (PEEP) and lung recruitment maneuvers are important ventilator strategies for improving oxygenation, but they may also influence cerebral blood flow, systemic hemodynamics, carbon dioxide levels, and brain electrical activity. The effects of PEEP-related ventilator changes on cortical function in neurocritical care patients remain insufficiently understood.

This prospective observational physiological study will evaluate changes in brain electrical activity and cerebral blood flow during clinically indicated lung recruitment maneuvers and PEEP adjustments in mechanically ventilated neurocritical care patients. Multimodal monitoring will include electroencephalography (EEG), transcranial Doppler ultrasound, invasive arterial blood pressure, end-tidal carbon dioxide, and routine clinical variables.

EEG-derived measures, including delta power ratio and related frequency-domain indicators, will be used to describe cortical activity. Cerebral blood flow velocity and low-frequency neurovascular coupling measures will be explored as secondary physiological outcomes. The study will examine whether PEEP-related changes are associated with alterations in EEG activity, cerebral blood flow, and neurovascular coupling, and whether these responses differ according to clinical status.

The results may help improve understanding of brain-lung interactions during mechanical ventilation and inform future studies on individualized ventilation strategies in neurocritical care.

Eligibility

Primary outcome measure(s)

• Change in EEG Delta Power Ratio During PEEP-Based Respiratory Interventions — During ventilator interventions (baseline, intervention, and recovery periods; approximately 30 minutes)
  Change in electroencephalography (EEG)-derived delta power ratio (DPR) measured before, during, and after recruitment maneuvers and positive end-expiratory pressure (PEEP) adjustments. DPR is calculated as the proportion of delta-band power relative to total EEG power and is used as an indicator of cortical electrophysiological activity.

Trial sites (1)

Other trials for the same condition