Hyperventilating during sleep

Why does my buddy always breath so rapidly after a night out of drinking? He’s had problems with handling alcohol including being hospitalized for alcohol poisoning 3 times. We had 6 beers tonight and a shot of fire ball and as soon as we get home he drops on the couch and IMMEDIATELY falls asleep and starts to breath rapidly. This used to scare me but it’s something that happens so much I wait up until he is breathing normally and can tell his body is more relaxed and calm before I sleep because he’s literally dropped on the floor after a couple of beers. (We don’t do any drugs whatsoever) If anyone has experienced this please give me some advice or tips. We’ve tried giving him the talk about drinking less and he doesn’t seem to care or want to stop drinking less, we’ve had many hospital trips before and I just don’t get it because I can drink and drink all day but he seems to be drunker than our whole friend group for longer and quicker. Any advice let me know! Hope I’m not being a bad friend I always make sure he’s good and not stopping breathing I’ve waited up hours by his side to make sure he’s okay. But yeah let us know our group needs answers lol. It seems to be the first 30 minutes of his sleep and it calms down but sometimes it will be hyperventilating for HOURS. Thanks