I don't usually bother. In fact, I don't get the opportunity. I've only ever had one other chick die from unknown causes since the incubator went in the bin. I believe that chick died due to head trauma.
The last chick that died here died from pasty butt. There were some problems during hatching and it looked as if there may have been some internal organ damage. I did do a bit of a necropsy but the organs aren't well enough developed to see any problems is what I found. I expect someone who does...