It didn't say he was SNOWED IN did it? He isn't burried alive or anything.
So, have the storm stop alittle bit AFTER he passes out, that way he doesn't get covered up and frozen to death.
THEN make Venra and such looking for Delia, she see's them coming, and She throws snow on Deccus to hide him from sight. Then, much like with an igloo, the insulation would keep him warm abit. THEN he digs his way out, and see's Vahal on the horizon, and makes it to the gate, passes out again from exhuation, and the guards pick him up and bring him in to the hospital.
Also, I have an idea. You know how I'm in there? (How could you NOT?) Well if something happens storywise, and I do something in it, you can ask me what I'd do. XD that way it would be more..."Authentic". :D