I can certainly understand the concern of using an electric blanket in an area which is exposed to so much potential for water spills... acid, bicarb, dialysate, blood, bleach solution for cleaning the machines, etc., etc., etc.
There are fluids EVERYWHERE in a dialysate unit and I would think this could present a major hazard.
However, that said..several of our patients make up their own little "heat packs".. cloth bags filled with corn which are heated in the microwave, or we heat up outdated saline bags to place on them.. there are many ways to add warmth. The simple act of wearing something on their head helps retain a LOT of their own body heat as well.
Hope you get this resolved for this patient... surely there is something that can be done to help keep him warm.