The emergency led to a temporary halt 12 minutes into the fixture
A medical emergency forced a temporary halt 12 minutes into the fixture, with staff from both teams racing across the pitch to assist the supporter, who was stabilised and then taken to hospital.
It was the second time this season a Premier League game had been halted during play due to a medical emergency. In October a Newcastle fan suffered a cardiac arrest at St James’ Park during the first half of their match against Tottenham and was stabilised inside the stadium before being taken to hospital.
Ranieri praised the way everyone reacted to the incident at Vicarage Road.
“Look, I think now all the medical staff are involved to help players and also the fans,” Ranieri said. “A long time ago there wasn’t a defibrillator and now it is much better.
“Of course I am happy, I am because now if something happens, in two or three minutes the medical staff arrive anywhere in the stadium and that is very, very important and it is important that the people around the man or woman who has something immediately ask the linesman or to somebody and then everyone is ready to help.”
Watford face another of the title favourites on Saturday as they host Manchester City, who have beaten the Hornets in every meeting between the sides since 2007.
But Ranieri insisted he will not approach the game with Pep Guardiola’s team any differently.
He said: “I prepare in the same way. I try to study very well the opponent and I try to tell the players everything they must do to try to win.
“Of course we have two situations on the pitch, when you attack and when you defend and of course we have to improve our attack and we have to improve our defence.
“(City) is a fantastic team. Guardiola is working very well, he has built a fantastic quality team and they can make the difference in every situation and for this reason we must be focused on the match 100 per cent.”