Authors: Uzun Sarıtaş, Pelin et al.
Journal of Cardiothoracic and Vascular Anesthesia Oct 26, 2025
Prospective observational study, 2025 (journal pending publication details).
This study investigated sedation depth using processed electroencephalography (pEEG) in adults with acute respiratory distress syndrome (ARDS) who were receiving continuous neuromuscular blockade (NMBA) in the ICU. Because traditional clinical assessments of sedation are unreliable in paralyzed patients, the researchers used pEEG parameters—Patient State Index (PSI) and Spectral Edge Frequency (SEF)—to characterize sedation adequacy over 24 hours.
Sixty adults with ARDS undergoing at least 24 hours of NMBA were monitored using PSI, SEF-right (SEF-R), and SEF-left (SEF-L) at seven time points (T0–T24). Sedation was maintained with propofol and/or midazolam, and fentanyl was used for analgesia. Sedation depth was categorized by PSI values: deep (<25), adequate (25–50), and potential inadequate (>50).
Results showed a median PSI of 53.3, meaning half of the patients had PSI values suggesting potentially inadequate sedation, and 16.7% had PSI >75—possibly indicating light sedation despite full paralysis. Hemodynamics did not differ between adequately and inadequately sedated patients. Patients receiving combined propofol and midazolam infusions had significantly lower (deeper) PSI values than those receiving single-agent regimens. Across all time points, PSI and SEF values declined significantly after T0, suggesting early deepening of sedation over time.
The authors conclude that a considerable proportion of paralyzed ICU patients may be under-sedated when assessed using pEEG, even under standard sedation protocols. They emphasize that pEEG can provide valuable, real-time neurophysiologic feedback to guide more individualized, brain-based sedation management—particularly in patients for whom clinical signs are unavailable.
What You Should Know
• In ARDS patients under NMBA, 50% had pEEG evidence of possible inadequate sedation.
• Combined propofol and midazolam produced deeper sedation than either drug alone.
• pEEG (using PSI and SEF) can reveal hidden variability in sedation depth that bedside assessment misses.
• pEEG should be used as a supplemental tool, not a replacement, for clinical judgment when managing paralyzed ICU patients.
Thank you for reading this summary of the forthcoming study in Journal of Cardiothoracic and Vascular Anesthesia on processed EEG monitoring and sedation depth in ARDS patients under neuromuscular blockade.