Urostomy Bag Losing Air When Connected to Bedside Drainage

Hello! I am asking for a neighbor: "My urostomy bag loses air/as if air suctioned out at night when I'm attached to bedside drainage." Has anyone else ever had this problem or can think of a solution? He has a parastomal hernia with an ulcer right above the stoma, and the os is on the side of his flush stoma (yup, poor guy!!) if that matters. But the issue here is the suction-like effect at night. I don't think the other stuff has anything to do with this problem, but maybe it does. Is there some kind of lubricant to put in the bag? I know some colostomies use bag lube. Thanks :))

Is he using a bottle system or bedside bag?

I have a Urostomy and use a drainage container attached to my bed frame. I always make sure I have some urine in my pouch prior to going to bed and hooking up the drainage container so that it creates a vacuum/suction effect. My pouch will also be flat/sandwiched together because of the suction effect but I have never had an issue as the urine always finds its way into the drainage container regardless if it appears no air is in the pouch. Hope this helps. 

Yes, mine does that too, but it has never been an issue. The urine always makes it to the bag. 

paul