A new heat and moisture exchanger for laryngectomized patients: endotracheal temperature and humidity

Objective: To assess the endotracheal temperature and humidity and clinical effects of 2 models
of a new heat and moisture exchanger (HME): Rplus, which has regular breathing resistance, and
Lplus, which has lower breathing resistance.
Methods: We measured endotracheal temperature and humidity in 10 laryngectomized patients, for 10 min each, with and without the HMEs. We sequentially tested 4 HME models (all Atos Medical, Ho¨rby, Sweden), in randomized order: Rplus, Lplus, Provox Normal (the HME we regularly use and which we considered the reference HME), and Stomvent (an older HME model). We also assessed the short-term clinical and practical effects of the Rplus and Lplus in a prospective 3-week trial with 13 laryngectomized patients.
Results: Rplus and Lplus had better humidification than Provox Normal (6.8 mg H2O/L, 4.3 mg H2O/L, and 3.7 mg H2O/L, respectively, P < .001), and no significant temperature difference. During the 3-week
study period, 7 of the 13 patients reported noticeably lower mucus production with Rplus and Lplus.
Conclusions: Rplus and Lplus had better heating and humidification than Provox Normal. Although Stomvent also performed well, its design is less convenient for laryngectomized patients. Further HME improvement is still warranted and should focus on improving the HME’s heating capacity.