Influence of passive humidification on respiratory heat loss in tracheotomized patients.
BACKGROUND
The aim of this study was to evaluate changes in total respiratory heat loss during use of a heat and moisture exchanger (HME) in tracheotomized patients.


METHODS
Tracheal humidity and temperature were measured before the application and during use of the HME (plastic foam impregnated with CaCl2), and total respiratory heat loss was calculated.


RESULTS
No significant difference was found between the convective heat exchange before and after use of the HME for a 10-minute period. When the HME was placed on the tracheal opening, the evaporative heat exchange and the total respiratory heat loss decreased significantly.


CONCLUSIONS
The results indicate that passive airway humidification is effective in tracheotomized patients even after a 10-minute period. However, the positive effect on the energy balance of the tracheal mucosa after prolonged use of the HME remains to be proven.
Department of Otorhinolaryngology, University of Ulm, Frauensteige 12, 89075 Ulm, Germany. ajnirozsasi@aol.com
Ajnacska
A
Rozsasi
Richard
R
Leiacker
Yvonne
Y
Fischer
Tilman
T
Keck
D001831:Body Temperature; D001833:Body Temperature Regulation / Q000502:physiology; D006801:Humans; D006813:Humidity; D008875:Middle Aged; D011446:Prospective Studies; D014132:Trachea / Q000502:physiology*; D014140:Tracheotomy