Smith Medical do them, see:
https://www.smiths-medical.com/prod...ovent-t2-heat-and-moisture-exchanger-hmeIt's called a Swedish Nose because it was invented in Sweden and because it humidifies incoming air like her real nose that she's not using. A Swedish nose/thermovent sits over the end of tracheostomy tube. Such devices are assessed during 2 hourly checks and changed when soiled, or at least every 24 hours. To prevent clogging up the Swedish nose and therefore interfering with respiration.
