For all my issues with historical fiction, this is not horrible. I still like the medical history background best, and I am beginning to wonder when/whether the "author" is going to introduce Dr. Simpson's trialling chloroform instead of ether as the story is set, I believe, in the year that Simpson started promoting chloroform. I would expect there be a period of Simpson experimenting with the substance throughout the year, but so far there is not a whiff of this. (Sorry, I had to.)
Also, I've learned that the author is actually a team of writers: Chris Brookmyre and anaesthetist Dr Marisa Haetzman. This may account for the medical element being quite well-written.
Overall, tho, this is not ground-breaking literature. It's an easy read to work away to, which is exactly what I was hoping for.