My Dad had a similar problem. We had to take him to ER because of a fever and chills and leaking around the tube (he had the external kind). He was using the largest diameter tube when the whole thing stopped draining. Three weeks after he succumbed.
I believe the internal stents were preferred, but my Dad's tumor did not allow for this. I hope your husband has a caring IR doctor. Our made us feel like we were nots for always taking him to ER to get his drain bag checked. But then again, my Dad had Kaiser.