Prevention aspects

Also a study was performed to investigate whether the use of an HME could prevent the development or reduce the severity of respiratory symptoms by initiating use of the device as soon as possible following total laryngectomy.7 Comparing the pulmonary complaints in a regular user and a non-regular user group at 3 and 6 months postoperatively, statistically significant group differences over time in the frequency of forced expectoration, and stoma cleaning and marginally significant differences in sputum production were observed. A clear trend could be seen, with regular HME users reporting a decline in respiratory symptoms over time as compared with non-regular HME users who reported an increase in these symptoms. These results show that an early start can prevent the development of respiratory symptoms considerably.From these and other studies, it can be concluded that, at present, the only effective non-pharmaceutical treatment of pulmonary problems in laryngectomized patients is the regular use of an HME.

This has been substantiated by McRae and Jones, who demonstrated that the application of an HME results in an objective improvement of several important physical parameters.8 In the normal situation the temperature is 36°C and the relative humidity 98% at the subglottic level (see figure right).

This situation is significantly changed after total laryngectomy. Under room temperature and humidity conditions, they observed an increase of the tracheal temperature from 20º to almost 29ºC, and of the relative humidity from 42% to 65% after applying an HME (figure right).

The figures show this schematically. Furthermore, they could demonstrate a significant increase in the tissue oxygenation after reinstalling the breathing resistance by means of a HME, confirming the improvements of the pulmonary physiology (figure right).