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

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.