Humidification and secretion volume in mechanically ventilated patients.
OBJECTIVE
To determine potential effects of humidification on the volume of airway secretions in mechanically ventilated patients.


METHODS
Water vapor delivery from devices providing non-heated-wire humidification, heated-wire humidification, and heat and moisture exchanger (HME) were quantified on the bench. Then, patients requiring 24-hour mechanical ventilation were exposed sequentially to each of these humidification devices, and secretions were removed and measured by suctioning every hour during the last 4 hours of the 24-hour study period.


RESULTS
In vitro water vapor delivery was greater using non-heated-wire humidification, compared to heated-wire humidification and HME. In vivo, a total of 9 patients were studied. Secretion volume following humidification by non-heated-wire humidification was significantly greater than for heated-wire humidification and HME (P=.004).


CONCLUSIONS
The volume of secretions appeared to be linked to humidification, as greater water vapor delivery measured in vitro was associated with greater secretion volume in vivo.
Department of Pulmonary and Critical Care Medicine, Stony Brook University Medical Center, State University of New York at Stony Brook, HSC T 17-040, Stony Brook, NY 11794, USA.
Mario
M
Solomita
Lucy B
LB
Palmer
Feroza
F
Daroowalla
Jeffrey
J
Liu
Dori
D
Miller
Deniese S
DS
LeBlanc
Gerald C
GC
Smaldone
D000328:Adult; D000336:Aerosols; D000368:Aged; D005260:Female; D006801:Humans; D006813:Humidity; D008297:Male; D008875:Middle Aged; D009330:Nebulizers and Vaporizers; D012121:Respiration, Artificial / Q000009:adverse effects* / Q000295:instrumentation*; D013183:Sputum / Q000378:metabolism*
D000336:Aerosols