I had an emergency c section but before the decision was made I was in labour and had had an epidural and they used the cold spray on me.
From what I was told the cold spray was used on me to see whether they had given me the correct dosage or whether they needed to alter it. They sprayed me from my belly button up to my neck and I had to say when I could feel the cold. I could feel it when they were kind of in the middle of my boobs on my breast plate. The midwife said that the dosage was too high and they needed me to regain my sesation back in my chest, so just below where boobs. They lowered the dosage and continued to spray test me until I could feel it in the right place.
When I was in theatre they didnt use the spray, they just asked me whether I could feel a nipping or a scratch feeling, I said scratch and they upped my epidural till it felt like someone nipping me. My husband told me later that they were cutting me open at that point and the scratch I could feel was them actually cutting me. It didnt hurt though, but I definitely felt a scratch on my skin.