Not sure if anyone has been affected taking their pet to the vets, but there's a national shortage of one of the veterinary anaesthetic gases at the moment due to a manufacturing problem preventing its manufacture. It's likely to last through until March.
There are alternatives, but each anaesthetic installation will be locked into one type or another - the gases have different characteristics and can't be swapped about.
www.bva.co.uk/news-campaigns-and-policy/newsroom/news-releases/shortage-of-isoflurane/