The case for replacing Protamine is dramatically stronger than replacing Thrombin
I use protamine everyday. I have never experienced a significant reaction nor have I heard of one. That includes 25 years of morbidity and mortality conferences.
If you give it IV push it can casue transient hypotension but no one with half a brain gives it IV push.
I don't buy the medicolegal aspect of the arguement. We deal with that 24/7 already.
FWIW I have had several significant reactions (transient 1-2 minutes) with bovine thrombin which no one can explain. I exclusively use recothrom now.