What were you swarmed by? You do need some sort of AOE type weapon to deal with ticks, and you have to be fast with it if you don't have the root chest piece on. A 2* tick will kill you very fast.

I generally use atgier, but I'm going to try the iron sledge this time.

Go slow and use bonemass power. Sometimes, depending on my gear, I will only go through mines with bonemass enabled. When it wears off I go back out and wait for it to regen. That's what I did when I was wearing Fenris armor and fighting with a knife.