User blog comment:FairyRaven/Fairy Tail Chapter 324: The One Who Closes The Door, Review and Commentary/@comment-112.198.77.251-20130322214110/@comment-84.113.52.218-20130322220626

Actually if you look at the picture with Kagura being stabbed, she wasn't even stabbed through the stomach. She was stabbed through the side. Unless I misremember the picture (or biology classes) there should only be muscles there. At worst the intestines got nicked a bit, but there are no vital organs or major arteries there that would kill someone immediately.

With that cloak she's wearing it's hard to tell were exactly the sword hit, but future Lucy was bleeding from the mouth, which means that either the airpipe and/or a lung (considering the width of the blade maybe even both lungs) were pierced, not to mention there are plenty of major arteries going through that area.