Heard about this from @Aller_MD but his twitter link wasn't working for me.
"Life-threatening intraoperative anaphylaxis to gelatin in Floseal during pediatric spinal surgery"
http://www.jaci-inpractice.org/article/S2213-2198(14)00197-4/abstract (http://www.jaci-inpractice.org/article/S2213-2198(14)00197-4/abstract)