Dan - anethetists also try to pump sufficient fluid into them when they're under (more than they would a non-breastfeeding person) so their milk supply isn't affected. For example, a person might have a minor op where no fluids are used or only whilst they are under, the BFing mother usually has that bag up until it has run through. I've yet to meet an anethetist who wasn't BFing friendly and did everything possible to ensure the Mother's supply and the feeding were uninterrupted.

HTH

MG