TY - JOUR
T1 - The influence of a heat and moisture exchanger on tracheal climate in a cold environment
AU - Zuur, J. Karel
AU - Muller, Sara H.
AU - Vincent, Andrew
AU - Sinaasappel, Michiel
AU - de Jongh, Frans H.C.
AU - Hilgers, Frans J.M.
N1 - Funding Information:
This study is part of a project funded by the Michel Keijzer Foundation of the Dutch Laryngectomee Society. Furthermore, the Department of Head and Neck Oncology and Surgery of the Netherlands Cancer Institute receives an unrestricted research grant from Atos Medical AB, Hörby, Sweden, and part of this study was carried out under this research grant.
Funding Information:
We are greatly indebted to the Michel Keijzer Foundation, under auspices of the Dutch Laryngectomee Society (NSVG), for their financial support of the pulmonary rehabilitation project. Part of the research has been conducted under the unrestricted research grant of Atos Medical, Sweden. We gratefully acknowledge Ruud Voorn, Frits de Vries and Iwan Dobbe of the Medical Technological Development department of the Academic Medical Center, University of Amsterdam, for helpful technical discussions. Tom Leenhoven of Viasys Healthcare is acknowledged for placing the Respitrace QDC at our disposal.
PY - 2009/9
Y1 - 2009/9
N2 - Objective: The incidence of pulmonary complaints, severe tracheitis and lung function deterioration is increased during wintertime in laryngectomized individuals. We analyzed how a heat and moisture exchanger (HME) performs in cold and dry ambient circumstances, and how its efficiency in this environmental climate might be improved. Study design: Randomized crossover. Methods: Intra-tracheal temperature and humidity were measured in 10 laryngectomized patients with and without HME, in a cold (mean, 4.7 °C) and dry (mean, 4.5 mgH2O/L) room. Results: Presence of an HME causes the intra-tracheal mean humidity minima and maxima to increase with 4.2 mgH2O/L (95%CI: 3.3-5.0 mgH2O/L; p < 0.001) and 2.4 mgH2O/L (95%CI: 1.7-3.1 mgH2O/L; p < 0.001), respectively. The intra-tracheal mean temperature minima and maxima increased with 3.9 °C (95%CI: 2.7-5.1 °C; p < 0.001) and 1.2 °C (95%CI: 0.8-1.2 °C; p < 0.001), respectively. In the majority of patients, the calculated relative humidity values appear to reach well above 100% during inspiration. Conclusion: In a cold environment, presence of an HME significantly increases both inspiratory and expiratory temperature and humidity values. Relative humidity calculations suggest the formation of condense droplets during inspiration. To further increase its effectiveness, improvement of the HME's thermal capacity should be aimed for.
AB - Objective: The incidence of pulmonary complaints, severe tracheitis and lung function deterioration is increased during wintertime in laryngectomized individuals. We analyzed how a heat and moisture exchanger (HME) performs in cold and dry ambient circumstances, and how its efficiency in this environmental climate might be improved. Study design: Randomized crossover. Methods: Intra-tracheal temperature and humidity were measured in 10 laryngectomized patients with and without HME, in a cold (mean, 4.7 °C) and dry (mean, 4.5 mgH2O/L) room. Results: Presence of an HME causes the intra-tracheal mean humidity minima and maxima to increase with 4.2 mgH2O/L (95%CI: 3.3-5.0 mgH2O/L; p < 0.001) and 2.4 mgH2O/L (95%CI: 1.7-3.1 mgH2O/L; p < 0.001), respectively. The intra-tracheal mean temperature minima and maxima increased with 3.9 °C (95%CI: 2.7-5.1 °C; p < 0.001) and 1.2 °C (95%CI: 0.8-1.2 °C; p < 0.001), respectively. In the majority of patients, the calculated relative humidity values appear to reach well above 100% during inspiration. Conclusion: In a cold environment, presence of an HME significantly increases both inspiratory and expiratory temperature and humidity values. Relative humidity calculations suggest the formation of condense droplets during inspiration. To further increase its effectiveness, improvement of the HME's thermal capacity should be aimed for.
KW - Airway climate assessment
KW - Cold environment
KW - Heat and moisture exchanger
KW - Humidity
KW - Temperature
UR - https://www.scopus.com/pages/publications/68349086913
U2 - 10.1016/j.medengphy.2009.04.004
DO - 10.1016/j.medengphy.2009.04.004
M3 - Article
C2 - 19481491
AN - SCOPUS:68349086913
SN - 1350-4533
VL - 31
SP - 852
EP - 857
JO - Medical Engineering and Physics
JF - Medical Engineering and Physics
IS - 7
ER -