Invasive ventilator exhaust in critical care: aerosol transmission risks and management strategies-a narrative review

Invasive mechanical ventilation (IMV) is essential in intensive care, yet aerosols released with ventilator exhaust remain an under-recognized source of airborne transmission and occupational exposure. This review outlines how exhaust-borne aerosols are generated and dispersed in clinical workflows, with amplification during airway suctioning, therapeutic nebulization, and inhaled volatile sedation. We compare principal mitigation options-including heat-and-moisture exchanger (HME) devices and high-efficiency particulate air filtration (HEPA), directed discharge, and chemical inactivation-across effectiveness, operational complexity, adaptability, and strength of evidence. Building on a patient-device-environment framework, we propose a scenario-based, three-tier prevention strategy that aligns patient-side filtration, circuit and exhaust-end control, and ICU room-level airflow engineering with context-appropriate monitoring.Conclusion: Ventilator-exhaust management is feasible with current technologies, but standardized performance indicators and multicenter studies are needed to quantify reductions in cross-infection and occupational exposure and to inform harmonized technical standards and guidance.