I Have A Mastiff With A Problem--I Fear For My Life

I have a male Cane Corso/English Mastiff who we will call 'Petey' (this could damage his reputation). He will be 2 in March and, at 140 lbs, is still growing. He's the best dog in the world--friendly, energetic (yet will take naps with me, his sleep-deprived mom), and he loves his brother, a Chihuahua. He's never chewed on anything that I own (which is good, because I think he could fit my entire dresser in his mouth. Including the lamp.) But, we do have a serious problem.

Petey is...flatulent. To an extreme degree. Now, I know a lot of you out there are saying, 'Hey, my dog (husband/boyfriend) farts all the time, so what's the problem?' I don't know how to explain it, but the best way to describe Petey's gaseous expulsions is with this word: 'heavy'. Like a dense fog settling on the mountains, Petey's farts will settle in the lower 3' of the room--about the altitude I inhabit while asleep. Thus, I fear that he may kill me (accidentally, I hope) in my sleep. Let me explain how the routine (when you go through this about 100 times a day, you make a routine) works:

-I'm in bed, innocently typing on the computer when I hear it: 'FFFWWWWWPPPPPP'
-I look over at Petey, who was asleep next to my bed, and he is now fixated on his butt, with a look of confusion and wonder ('What was that!? Where did it go?').
-Petey looks up at me (no doubt wondering if I saw the little creature that he thinks ran out of his butt while he wasn't looking), and, after taking in my terrified gaze, thinks that he has done something HORRIFYING and he must move away from me before I yell at him.
-Petey jumps to his feet as I throw my comforter over my head to prevent my eyes from watering due to the noxious gas. In his attempt to slink out of the room unnoticed, he has shaken his intestines, which, in response, proceed to expel gas with his every step. In his mind, lots of little butt-dwelling critters are escaping, foiling his stealthy exit. I have yet to break it to him that he isn't stealthy at all, with or without the butt-dwelling critters.
-Hearing him exit the room, I crack the window behind my bed and shove my head out. 3 minutes later, I am in the clear. I shut the window and continue on with my work--shaken, but alive.

(At times I will get up to find him in another room, intently staring at his butt in hopes of catching one of those pesky critters.)

I live in fear. These are SO BAD that I actually wake up in the middle of the night. Please, does anyone have any sort of home remedy? I've changed his food, stopped giving him rawhide, tried to eliminate tasty treats that I know cause gas in humans (cheese, anyone?)--everything I can think of, but my life is still on the line! I am a student, so money is tight, please keep this in mind!
Thanks!