‘Listen to me, Jane, an ambulance is coming but I need you to help your father by giving him chest compressions. He’s on the floor already, right? He needs to be on his back, on a flat surface.’

The instructions appear on my computer screen, though I know them by heart. On the map next to them, a little moving dot shows the progress of the ambulance the dispatcher has sent. Six minutes away.

Jane is panting. ‘He’s on his side. I can’t . . . he’s a big man.’

‘Is there anyone there to help you?’

‘No. Oh shit, Dad . . .’

‘All right, get him flat on his back as quickly as you can.’

‘But what if he hits his head?’

This part is hard: how do you tell the caller that the person they love is beyond pain, as far as we know?

‘Please do as I say.’

She groans, her mouth right by the receiver; I picture her, the phone tucked into the crook of her neck. I hear a slap as the patient falls. ‘Is he in the right position now, Jane?’

‘Yeah, I think so. But why isn’t he breathing?’

‘You need to help him. Kneel down next to him and move his clothes out of the way so you can see his chest properly.’

A flashback: the sight of Joel’s perfect torso as I pulled up his T-shirt to do what I am asking Jane to. I replace the image with one of this older man, with more fragile ribs and looser skin, but so much life still ahead.

My current patient’s collapse was witnessed. Like Joel, but unlike many others, he does have a chance.

‘Now place your palm right in the centre of his chest, below the nipples. OK so far?’

‘I think so.’

On the radio someone says: The rows over parking are splitting us down the middle. Neighbour against neighbour.

‘Now place the other hand over the first one and begin to push down, hard, by at least two inches, at the pace I’m going to give you: one and two and three and four. Keep your arms straight, one and two and three and four . . . Are you doing that now, Jane?’

‘It’s going to hurt him. Dad, wake up!’

I’ve lost count of the number of times I’ve read this script in the past eleven months with the service. It hasn’t worked once. The crews have never been able to restore spontaneous circulation. My first death almost broke me, because saving Joel had convinced me I was invincible.

But I got over it. You just do.

A colleague stands close by, both of us staring at the screen, willing the crew to get there faster.

‘My arms are getting tired . . .’

‘I know, Jane. Help is nearly there but don’t stop. Keep that rhythm going, hard pushes.’