Vibrating Mesh Nebulizers (Aerogen) Are Superior to Manual Jet Nebulizers in Intubated Patients
For mechanically ventilated patients, vibrating mesh nebulizers (VMN) such as Aerogen should be strongly preferred over manual jet nebulizers (JN) due to superior drug delivery efficiency, reduced fugitive aerosol emissions, and better integration with ventilator circuits. 1, 2
Key Evidence Supporting Vibrating Mesh Nebulizers
Drug Delivery Efficiency
VMN devices deliver significantly more medication to the lungs compared to jet nebulizers in mechanically ventilated patients. 2 The consensus from the European Society of Clinical Microbiology and Infectious Diseases explicitly recommends vibrating-mesh nebulizers over jet or ultrasonic nebulizers for intubated patients. 2
Aerosol deposition from jet nebulizers in mechanically ventilated adults has been measured at only 1.2-3.0% of the nominal dose, whereas VMN technology achieves higher lung deposition rates. 1
Safety and Environmental Considerations
VMN devices produce substantially lower fugitive aerosol concentrations in the room compared to jet nebulizers, which is critical for healthcare worker safety and infection control. 1 Studies comparing the two technologies found higher aerosol concentrations dispersed into the environment with jet nebulizers versus VMN across all patient interfaces tested. 1
The reduced environmental contamination with VMN is particularly important given concerns about aerosol-generating procedures, though current evidence remains insufficient to definitively classify nebulization as an AGP. 1
Optimal Technical Setup for VMN in Intubated Patients
Circuit Placement and Configuration
Place the VMN in-line with the ventilator circuit in the inspiratory limb, ideally positioned between the humidifier and the patient Y-piece to maximize drug delivery. 1, 2
Use respiratory circuits specifically designed with smooth inner surfaces and minimal sharp angles to decrease turbulence and limit circuit deposition. 2
Ventilator Settings During Nebulization
Apply these specific ventilator parameters during nebulization to optimize drug delivery: 2
- Volume-controlled mode with constant inspiratory flow
- Tidal volume: 8 mL/kg
- Respiratory rate: 12-15 breaths per minute
- Inspiratory:expiratory ratio: 50%
- Inspiratory pause: 20%
- PEEP: 5-10 cm H₂O
Critical Equipment Modifications
Disconnect heat and moisture exchangers (HME) and turn off heated humidifiers during nebulization to prevent massive aerosol particle loss through trapping and condensation. 1, 2 This is essential—failure to do so results in treatment failure.
Insert an expiratory filter on the expiratory limb to protect the ventilator and change it between each nebulization to prevent flow obstruction. 2
If patient-ventilator dyssynchrony occurs, administer short-acting sedation to ensure coordination and avoid peak decelerating inspiratory flow that reduces drug delivery. 2
Common Pitfalls to Avoid
Technical Errors Leading to Treatment Failure
Never leave humidification systems running during nebulization—this single error can cause up to 90% loss of aerosolized medication. 2
Avoid placing the nebulizer too far upstream in the circuit (near the humidifier), as this increases circuit deposition and reduces lung delivery. 3
Do not use jet nebulizers that require high gas flow rates (6-8 L/min) in ventilated patients, as this disrupts ventilator settings and increases environmental contamination. 1
Infection Control Considerations
Between treatments on the same patient, VMN devices should be cleaned, disinfected, and air-dried according to manufacturer instructions. 1
Use only sterile fluid for nebulization and dispense aseptically to prevent nosocomial infections. 1, 4
When Manual Jet Nebulizers Might Still Be Used
While VMN is superior, jet nebulizers may be acceptable in resource-limited settings if: 1
- VMN technology is unavailable
- The patient is spontaneously breathing (not mechanically ventilated)
- Proper infection control measures including filters and appropriate PPE are employed 1
However, for mechanically ventilated patients specifically, the evidence strongly favors VMN technology, and jet nebulizers should be considered suboptimal. 2