Hi,
TJack is right. You could either schedule an appointment with a pulmonologist or a sleep specialist.
It would depend on which one of the specialist doctor's would be available in your area or nearby hospital.
A pulmonary function test and sleep study would be done to determine the cause of his symptoms and he would be evaluated for relief in his symptoms when using a machine called the CPAP.
This type of sleep study is called the split night study - where one half of the night is used for diagnosis and the other half of the night for therapeutic CPAP application and titration of the CPAP pressures.
Do get back to us if you have any more doubts.
Hope this helps.
Good luck.
A pulmonary dr. is who he needs to see. That dr will order a sleep test and he will spend the night and be wired up. That will determine how bad his apnea is and if indeed he has it he will get a cpap machine and be in business. He will probably hate it in the beginning but will love it before long and won't leave home without it. His sleep will be so much better. Good wishes. TJack