That is a myth about her denying knowing anything about air embolism.
Judith Moritz and Jonathan Coffey, who produced the recent, shambolic episode of Panorama, played a really dirty trick in their book when they described this police interview. They said, like you, that she denied knowing anything about air embolism. Obviously if you've read it there, it's not your fault.
Here is what Lucy Letby actually said at that police interview. They're asking her about training:
Q: And what about air embolisms, Lucy? Did you receive any training in relation to those?
LL: No.
Q: Okay. Were you aware of them or?
LL: Not really, no.
Q: Have you heard of them before?
LL: Yes.
Q: When was that?
LL: I've heard of them more from an adult perspective.
Q: And tell me what that was in relation to.
LL: I don't know specifics. Like sometimes we've had mums on the unit who've been unwell and it's been found they've had AAP, pulmonary embolism. So that's just how I've heard of it via that.
Q: Specifically whilst working on the neonatal unit, have you ever come across it before?
LL: No.
Q: Has the air embolism training ever popped up in respect of dangers with other training that you might have had?
LL: Not that I can think of specifically.
Q: No, or any sort of general nursing training before you qualified?
LL: It's been mentioned in terms of line care. You'd have to be mindful that you don't leave a line open and things like that. But it's not something that's discussed frequently in any detail.
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And here's what Moritz and Coffey say:
When she was questioned by police, Letby said all nursing staff would be aware of the dangers of an air embolus [the air bubble itself], but she claimed she didn’t know much beyond this. She said ‘I don’t know exactly what [an air embolism] is. When we were taught about lines, we were taught about clearing lines because that’s what it would lead to.’ She also told police she was only aware of air embolisms in adults.
...
[The fact that Letby raised the danger of air embolism after Child O's port was left open(1)] also makes it harder to understand why Letby told police that she was only aware of air embolisms in adults when she clearly knew the risk to newborn babies. For the prosecution experts, these details will only give them further confidence in their interpretations. Neither Dewi Evans nor Sandie Bohin had seen Letby’s text messages or knew about the training course she had attended when they first presented their air embolism theory. If their theory was wrong, it was a remarkable coincidence.
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I don't think you need to take a particular view on Lucy Letby's guilt or innocence to see that Moritz and Coffey distorted Lucy Letby's words here. As she said, she knew leaving a line open risked air embolism. So of course it's not sinister that she should report this risk.
Terrible standards from the two BBC journalists here. They've straight-out misrepresented her. They've certainly undermined my trust in the corporation drastically with their melodramatic antics on this case.