Christopher Biggins, Matt Lucas and David Walliams were among the guests.
"She was properly sick and then she turned it on – that's the pro she was."
The former EastEnders star renamed himself "Wasp Kemp" as he shared a series of videos on Twitter.
The former EastEnders actor recently completed a documentary about dementia, which starred Dame Barbara and her husband Scott Mitchell.
Scott Mitchell has said a specialist told him to "prepare himself" that the EastEnders legend may need to move out of their home.
The former EastEnders star was diagnosed with Alzheimer’s in 2014.
Many were unimpressed that the former EastEnders star could film in a hospital where patients' families are not allowed to visit.
The former EastEnders star spent six months visiting HMP Belmarsh prison for his new ITV show.
Lorraine Kelly, Piers Morgan and Eamonn Holmes have also sent Barbara their best wishes.
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