Clinical application of volatile sedation in adult intensive care units: pharmacological mechanisms, delivery systems, and safety.

Sedation is essential in critically ill mechanically ventilated patients, yet conventional intravenous agents carry risks of accumulation, organ-dependent clearance, and adverse effects. Volatile anesthetics offer several pharmacokinetic advantages, but their adoption in the intensive care unit has historically been limited by technical constraints. This review offers an updated, clinically focused overview of volatile- based sedation in adult intensive care units, covering pharmacological mechanisms, delivery systems, clinical outcomes, safety, and practical application. This review was conducted through systematic searching of PubMed, Scopus, and Web of Science for studies published between January 2016 and December 2025. Sevoflurane and isoflurane achieve sedation primarily via γ-aminobutyric acid type A receptor modulation and offer organ-independent clearance, rapid onset/offset, and real-time end-tidal monitoring. Modern delivery systems, including reflection devices (Sedaconda-ACD) and automated platforms (MIRUS), have improved intensive care unit feasibility. Clinical evidence suggests volatile sedation may reduce awakening times and duration of mechanical ventilation compared with intravenous agents; however, results across randomized trials and meta-analyses are heterogeneous. Potential benefits have been reported in acute respiratory distress syndrome, post-cardiac arrest care, neurocritical illness, extracorporeal membrane oxygenation, and refractory agitation, but robust evidence is lacking across all settings. Limitations include hemodynamic effects, increased circuit dead space, renal safety concerns with sevoflurane, infrastructure requirements, occupational exposure, environmental impact, and cost. Volatile sedation is a feasible and pharmacologically rational option for selected mechanically ventilated intensive care unit patients, particularly those requiring prolonged sedation or with organ dysfunction limiting conventional agents. Current evidence does not support universal superiority over intravenous sedation. Inhaled anesthetics should be incorporated into individualized, multimodal sedation strategies within structured institutional frameworks. Large multicenter trials are needed to clarify effects on mortality, long-term neurological outcomes, and quality of life.