Short-term endotracheal climate changes and clinical effects of a heat and moisture exchanger with an integrated electrostatic virus and bacterial filter developed for laryngectomized individuals

Abstract

Conclusion: Both the regularly used heat and moisture exchanger (R-HME) and the HME with both an antimicrobial and hygroscopic element (F-HME) are effective moisture exchangers. The antimicrobial filter of the F-HME acts as a heat exchanger. The external features of the F-HME were experienced as inconvenient, but decreased sputum production was reported as well. Objectives: Recently an HME with an integrated antimicrobial filter has become available for use in laryngectomized patients. The purpose of this study was to assess its short-term endotracheal climate changes and feasibility in daily practice. Methods: Endotracheal temperature and humidity were successfully measured in 13 laryngectomized patients (2652 analysed full breaths), during 10 min rest-breathing with the R-HME, with an F-HME and without HME in a randomized sequence. Additionally, a 3 week prospective clinical feasibility trial was conducted in 17 laryngectomized patients. Results: Both R-HME and F-HME increase endotracheal minimum humidity values (5.8 and 4.7 mgH₂O/L, respectively; p < 0.0001). Compared with open stoma breathing, in contrast to the R-HME, the F-HME increases both end-inspiratory and end-expiratory temperature values (1.1°C, and 0.6°C, respectively). After the 3-week clinical feasibility trial, one patient dropped out; 11 patients (11/16 = 69%) disliked the larger design of the F-HME and all patients reported less optimal airtight occlusion. Five patients (5/16 = 31%) reported remarkably decreased sputum production.

Keywords::

• Total laryngectomy
• heat and moisture exchanger
• tracheal climate
• temperature and humidity
• virus and bacterial filter
• filtration
• patient compliance
• heat capacity
• short-term clinical effects

Acknowledgments

Marcel van der Horst and Morgan Shehata, formerly Department of Medical Technology Development of the AMC, University of Amsterdam, are acknowledged for their continued technical support. This study was conducted (in part) under an unrestricted research grant from Atos Medical AB, Hörby, Sweden.