Hillingdon Hospital has only managed to see 77% of Accident and Emergency patients within 4 hours this week, according to figures presented by the BBC.
The Government expects each hospital to see urgent patients within 4 hours, and this is often acheived, including at Hillingdon.
But this week there have been worrying stories across the country of hospital struggling to cope. As well as Hillingdon's performance being reported as 77%, nearby Ealing fared even worse at 63.9%
Lib Dem Activist Pete Dollimore said "Residents will naturally be concerned about this short term blip but the big question is how quickly will things return to normal. With the worst of the winter weather probably ahead of us, we need to know we can rely on our A&E's in case of need."