Oh this brings back so many memories and makes me .
The same happened to me, except as well as a high nuchal measurement they thought they saw an exomphalos. Consultant who we FINALLY saw 6 hours later said that in all probability our baby had Edwards syndromw and would probably not survive, and started talking about terminations. We were devastated and asked for more test.
We were referred to a specialist unit for more tests and a CVS.
The first imprtant point they raised was our dating. Apparently the exact age of you baby makes a huge difference when measuring nuchal translucency. (and looking for other soft markers like exomphalos...). So that's one thing to bear in mind. Turns out our baby was younger than we thought.
Secondly when they re-measured (with better kit and a more qualified person) they adjusted the measurement - it wasn't as large as the first scan had suggested.
We still ended up with a high-ish ratio - about 1:100 I think although can't really remember. So we went for a CVS, which wasn't fun but not awful.
Got the results bck after a couple of days and it tunred out that DD was fine - and indeed she is, 21 months and a little bundle of laughter and energy.
I'm not saying everything's going to be fine, necessarily, just that you can't know yet. And niether can your sonograper who simply isn't in a position to make those kind of calls at this stage, and IMHO is very very worng to. She could have encoouraged further investigation without upsetting and panicking you like she has.
As you said, these are soft markers only - not a conclusive result even if measured correctly says nothing for definite.
I really am and that you have had to go through this too.
Get all the opinions and further tests you need. Demand to speak to someone more qualified and take back up - partner, mum or best friend.
It's pointless my telling you not to panic when you obviously are going to, but try to hold on to the fact that nothing is conclusive yet ? really it's not.
TBH I'd ask for a referral to a Fetal Medicine Unit, like now. Scrap that, DEMAND that they refer you. You can't be expected to wait a week after news like that. You'll probably have to go down there, but I feel if oyu make enough noise they should sort you out.
Best of luck. Will go and fume on your behalf.
db
xx