Nebulization associated with bi-level noninvasive ventilation: analysis of pulmonary radioaerosol deposition.
Nebulization associated with noninvasive ventilation is used in emergency services and intensive care units.


OBJECTIVE
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.


METHODS
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).


CONCLUSIONS
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.
França
Eduardo E T
EE
Departamento de Fisioterapia, Universidade Federal de Pernambuco, Campus da UFPE, Av. Pro. Moraes Rego, Cidade Universitária Recife, Pernambuco, CEP 50670-901, Brazil.
Dornelas de Andrade
Armele F
AF
Cabral
Geovanna
G
Almeida Filho
Paulo
P
Silva
Kamary C
KC
Galindo Filho
Valdecir C
VC
Marinho
Patrícia E M
PE
Lemos
Andrea
A
Parreira
Verônica F
VF
D000280:Administration, Inhalation; D000328:Adult; D000336:Aerosols; D005260:Female; D006801:Humans; D008168:Lung / Q000000981:diagnostic imaging / Q000378:metabolism*; D008297:Male; D009330:Nebulizers and Vaporizers; D011877:Radionuclide Imaging; D012129:Respiratory Function Tests; D012138:Respiratory Therapy / Q000379:methods*; D016284:Technetium Tc 99m Pentetate / Q000008:administration & dosage / Q000493:pharmacokinetics*
D000336:Aerosols; D016284:Technetium Tc 99m Pentetate