Now, this is simple yet unthought-of when in the heat of an operation. Now, if you've gotten to the point where Aletheia's eye opens up and reveals the red and white cords, you KNOW what I'm talking about when I say that slashing the right cord - quickly - can be tricky. But if you follow these two tips, you should be fine:
1) When it gets down to a couple of cords, TIME for the one that's red. The second it turns white, stick your scalpel down and don't release it until it's cut. You shouldn't fail if you're fast enough.
2) Don't saw at the cords with the scalpel. Just hold your stylus down over the cord. It'll save you time and potentially your operation.
This operation can be frustrating at times, and although it's a bit easier from the first game, it can still be hard to get a good grade. Here's a good strategy for beating them fast:
1) The first one should be easy to get. Just follow Angie's instructions.
2) When several appear, inject them and cut, but DON'T REMOVE. Zoom around to them all, then start healing the veins.
3) Watch your patient's health! The open veins will still leech hit points away.