Arthur Haynes character complains of suffering a blood clot in the night which could have lead to a heart coronary. Strangley Haynes died of a heart attack in November 1966.
Dr. Miles Grimsdyke:
There you are, a souvenir of your stay, you'll be right as rain now.
O'Malley: Yes, we watched it on the telly, we thought you were a gonna at one point.
Tarquin Wendover: Look at that. Must be a piece of shrapnel I got in the war.
Sydney: The man on the TV said it was loose filling from...
When Sir Lancelot Spratt draws lines on Tarquin Wendover's chest to indicate where he will cut, they are the width of the pencil. A few seconds later the camera jumps back to his chest and they are about four times as wide.