title: Comparison of jet and ultrasonic nebulizer pulmonary aerosol deposition during mechanical ventilation.
abstract: Increased delivery of aerosol to a model lung (attached to a mechanical ventilator) has been demonstrated with an ultrasonic nebulizer as compared to a jet nebulizer. This study examined whether the increased aerosol deposition with an ultrasonic nebulizer could also be demonstrated in vivo. Seven patients (6 male and 1 female) were studied during mechanical ventilalion (Siemens Servo 900C, Middlesex, UK) after open heart surgery. Two studies were performed in each patient. In the first study, aerosol was delivered via a Siemens Servo 945 nebulizer system (high setting) driving a System 22 Acorn jet nebulizer (Medic-Aid, Sussex, UK) containing 3 mL (99m)technetium-labelled human serum albumin (99mTc-HSA) (50 microg; activity 74 MBq). In the second study, a DP100 ultrasonic nebulizer (DP Medical, Meylan, France) containing 12 mL 99mTc-HSA (50 microg; activity 185 MBq) was used. Pulmonary deposition was quantified using a gamma camera. The humidification of the circuit and the ventilator settings were kept constant according to the patient's clinical requirements. The total lung aerosol deposition (mean+/-SD), as a percentage of initial nebulizer activity, was greater using the ultrasonic nebulizer than using the jet nebulizer (53+/-1.4 vs 2.3+/-0.9%; p<0.002). The ultrasonic nebulizer was also associated with a reduction in the time required to complete nebulization (9 vs 21 min, respectively) (p<0.0001). Use of the DP100 ultrasonic nebulizer more than doubled lung deposition compared with the System 22 jet nebulizers in mechanically-ventilated patients. Their efficiency, speed of drug delivery, and compatibility with mechanical ventilator circuits make ultrasonic nebulizers potentially attractive for use during mechanical ventilation.
authors.affiliation: Intensive Therapy Unit, St Thomas' Hospital, UMDS, London, UK.
authors.forename: C J
authors.initials: CJ
authors.lastname: Harvey
authors.forename: M J
authors.initials: MJ
authors.lastname: O'Doherty
authors.forename: C J
authors.initials: CJ
authors.lastname: Page
authors.forename: S H
authors.initials: SH
authors.lastname: Thomas
authors.forename: T O
authors.initials: TO
authors.lastname: Nunan
authors.forename: D F
authors.initials: DF
authors.lastname: Treacher
mesh_terms: D000280:Administration, Inhalation; D000336:Aerosols / Q000008:administration & dosage* / Q000493:pharmacokinetics; D000368:Aged; D006348:Cardiac Surgical Procedures; D004867:Equipment Design; D005260:Female; D006801:Humans; D007442:Intubation, Intratracheal; D008297:Male; D008875:Middle Aged; D009330:Nebulizers and Vaporizers; D011182:Postoperative Care / Q000379:methods; D012121:Respiration, Artificial / Q000295:instrumentation* / Q000379:methods; D014465:Ultrasonics
chemical_list: D000336:Aerosols