Nebulization associated with bi-level noninvasive ventilation: analysis of pulmonary radioaerosol deposition

Respir Med. 2006 Apr;100(4):721-8. doi: 10.1016/j.rmed.2005.07.012. Epub 2005 Aug 31.


Nebulization associated with noninvasive ventilation is used in emergency services and intensive care units.

Purposes: To compare pulmonary radioaerosol deposition during jet nebulization associated to noninvasive ventilation versus spontaneous breathing nebulization; to measure the rate of lung depuration and the correlation between lung deposition, inspiratory flow and tidal volume (V(t)) using scintigraphy.

Subjects: Thirteen healthy volunteers (with normal spirometry), mean age (23.3+/-1.49) years, body mass index 21.2+/-2.3 kg/m(2).

Methods: Nebulization was performed in spontaneous breathing and associated with bi-level noninvasive ventilation (inspiratory pressure=12 cm H(2)O, expiratory pressure=5 cm H(2)O). The radioaerosol used in the nebulization was technetium (Tc99m) with diethylene triamine penta acetic acid, generated over a period of 9 min in a jet nebulizer. Analysis was performed through scintigraphy. Statistical analysis was performed by analysis of variance (for repeated measures), Bonferroni method, Student's t-test and Person's correlation.

Results: There was a decrease in radioaerosol lung deposition with nebulization associated to noninvasive ventilation (mean counts in spontaneous breathing 200,510+11,012 and mean counts in noninvasive ventilation 106,093+2811 (P<0.001). During spontaneous breathing nebulization there was a significant correlation between V(t) and radioaerosol deposition (r=0.565, P<0.05), also between inspiratory flow and radioaerosol deposition in the lungs (r=0.141, P<0.05). However, there was no correlation between V(t) and pulmonary deposition of radioaerosol in bi-level noninvasive ventilation nebulization (r=0.082).

Conclusion: During nebulization with noninvasive ventilation in healthy volunteers, there was an increase in V(t) associated to a higher inspiratory flow rate, without resulting in a significant increase in pulmonary radioaerosol deposition.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Administration, Inhalation
  • Adult
  • Aerosols
  • Female
  • Humans
  • Lung / diagnostic imaging
  • Lung / metabolism*
  • Male
  • Nebulizers and Vaporizers*
  • Radionuclide Imaging
  • Respiratory Function Tests
  • Respiratory Therapy / methods*
  • Technetium Tc 99m Pentetate / administration & dosage
  • Technetium Tc 99m Pentetate / pharmacokinetics*


  • Aerosols
  • Technetium Tc 99m Pentetate