Tonight’s episode of the award-winning medical documentary “24 Hours in A&E” is on at 9pm on Channel 4. Follow @StGeorgesTrust and #24HrsAE as we tweet during the live show.

75-year-old Gerry is rushed to A&E with a dangerously high heart rate of over 250 bpm. “A heart rate of 200-250 is a genuine medical emergency,” says consultant Will. “That’s an unsustainable rate for your heart to beat at. If the heart is beating really quickly it can lead you to have a cardiac arrest.”

Doctors aren’t able to slow Gerry’s heart rate down with drugs and their only option is to try to return his heart to a normal rhythm with an electric shock. They suspect the problem has been caused by an underlying chest infection that will need to be brought under control.

Gerry’s wife Julie talks about meeting Gerry through the construction company where they both worked. Julie’s first husband died from cancer and meeting Gerry gave her a second chance for happiness. “It does make you treasure things,” says Julie. “Life passes you by so quickly and you should make the most of everything that you have.”

92-year-old Margaret has come to St George’s after falling over and hitting her head. The cut may be small, but doctor Tom wants to carry out a series of tests to make sure there’s no underlying cause for her falling. They discover that she too has a dangerously high heart rate.

Margaret is not your average 92-year-old. She lives alone and looks after herself as well as spending time with younger friend Yvette. “We go out to lunch, we go to exhibitions sometimes,” says Margaret. “It’s lovely having somebody younger too, it’s what I need…she’s not going to die before me!”

Margaret talks about losing her husband to Alzheimer’s and her daughter to cancer. “At the time I thought it should have been me. It wasn’t unfortunately,” she says. “It was a great upset. I miss her terribly.”

Meanwhile 6-year-old Daniel has an infected blister on his foot and has come to A&E to get it sorted out, accompanied by his mum and three siblings. But Daniel needs some reassurance and distraction, as well as gas and air, so that the medics can make him better.