Sorry that your husband is having difficulties. I would agree that the most likely etiology of your husband's sensory changes is the positioning on his elbows. He might have put too much pressure on the ulnar nerve that travels near the elbow. However, one never knows what might be going on and the positioning is just a red herring. I would see a neurologist and have him/her evaluate the sensory changes. Likely it is the positioning but a good evaluation will ease your minds and also a better prognostication can be given. A medication such as neurontin might help with the paresthesias.
CCF Neuro MD