Controlling thermals under a blanket

No.12421525 ViewReplyOriginalReport
I sleep under two big blankets during the winter. I don't like heating my room so it is usually 10C (50F) degrees.
How can I keep the space under my blanket at a comfortable temperature? Every night I wake up from it overheating or from not being warm enough.
I was thinking of just having a simple tube (say a short garden hose) going from under the blanket to outside the blanket. That way, cool air will keep flowing in at a steady rate, with hot air slowly escaping from all directions.
Thoughts?