Health Organization for Pudendal Education

Hi everybody, I'm looking for recent scientific articles about the fact that is safer to have guided pudendal nerve blocks instead of non guided. Could you help me please? I mean if someone does have some recent articles that he or she has already found. I'll be really grateful.
I'm in a hurry and I've already researched on medline but it too laborious and long lasting.

Francesca, in 10 years of following the literature, I don't remember ever seeing any literature on unguided nerve pudendal nerve blocks, or any literature comparing guided with unguided. There are a number of publications on guided PN blocks, including this most recent one: http://www.ncbi.nlm.nih.gov/pubmed/24951215

Violet