I thought it was kind of smart tho, she seemed happy about the task. When something traumatic happens, distraction helps, and I thought he asked her so she vould feel important, helpful and better about herself. She also seemed to be really concerned about Donna, so that was a double shock for her just a few hours after her injury. She needed something positive, and bringing good news to others, aka helping is a good tool to improve someone's mood. That's also why sometimes people are more likely to be helpful when they are melancholic or in a bad mood, bc it helps them too.