Humidification and secretion volume in mechanically ventilated patients
Solomita, M.; Palmer, L.B.; Daroowalla, F.; Liu, J.; Miller, D.; LeBlanc, D.S.; Smaldone, G.C.
Respiratory Care 54(10): 1329-1335
2009
ISSN/ISBN: 0020-1324 PMID: 19796412 Document Number: 637506
To determine potential effects of humidification on the volume of airway secretions in mechanically ventilated patients. 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. 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). 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.