If you have a vented TB patient, what filter needs to be used?

• A. A standard bacterial/viral filter on the expiratory limb
• B. A HEPA filter on the expiratory limb (and preferably on the inspiratory limb)
• C. No special filter is required
• D. Humidification filter is sufficient

Answer: (B)

Filtration of airborne pathogens within a ventilator circuit is essential when a patient with active TB is vented, to prevent spreading the infection into the environment. TB travels in tiny aerosol particles that can linger in the air, so you need a filter with high efficiency. A HEPA filter on the expiratory limb effectively traps these aerosols before the air leaves the ventilator circuit, protecting staff and other patients. If feasible, adding a HEPA filter on the inspiratory limb provides an extra barrier to keep the circuit itself clean. Standard bacterial/viral filters may not remove TB aerosols as reliably, and humidification filters alone do not offer adequate protection. Maintaining airborne precautions in addition to using a HEPA filter on both limbs, when possible, helps minimize transmission risk.