Hello Laura and Bob
The suction machine is called I believe a Yankeur, not sure of spelling. You might want to try keeping his air moist and ask his Doc about something to loosen the phlegm. If I had a brain I would be able to remember the name of the over the counter meds Pete used.
This is a hard time in the treatment , when radiation finishes. His mouth will be sore for a while.
I am sure you will get lots of advice soon,when everyone sees your message.
Please let us know how he progresses and if you need anything we will try to help.

Take care both of you
Love
Marica