‘You’re going to put that into me? But it’s huge!’ His eyes dart across to the long metal device I’m holding, then he winces involuntarily and shifts away from where I’m perched on the edge of his bed. I see a white flash of his exposed buttocks. They look even more frightened than he does. Or I am.

We both glance down at the 18-gauge cannula gripped in my sweaty right hand. My mental picture of a virgin high-class escort and her nervous virgin client dissolves into reality. For a moment, I almost wish I was an escort. Better that than, on my first day as a doctor, inserting an enormous metal needle into a patient’s skinny-looking vein—a feat I’ve never yet managed to accomplish, though as a medical student I had plenty of opportunity to master it. ‘We’ll learn on the actual job,’ Estelle and I used to tell each other with the confidence of people who could put off any unpleasant tasks into a distant future. Well, this is the job, and that distant future is suddenly the present.

‘Yes, I’ve done this before,’ I lie, trying to smile but knowing it’s coming out more like a demented grimace. If I told him the truth we’d probably both pass out with fear, further delaying the inevitable.

He doesn’t respond, but he grants me implied consent by extending his arm in front of me. I have a mental image of Jesus on the cross, arms outstretched, the stigmata of crucifixion mirroring the icon on the wall above the bed. I’m meant to be his angel saving him from his fate, but instead all that happens is I stare at his juicy, bulging vein, slightly purple underneath the translucent skin, and swallow.

Lord, grant me the serenity to accept the things I cannot change …

I pull the tourniquet on his upper arm tight. I see him tense slightly, but to his credit my virgin cannula client says nothing. He surrenders to his unexpected angel, and waits.

Courage to change the things I can …

I unsheath the cannula, stare at the end of the sharp needle, and take a breath. With my free hand, I tap along the vein, hoping desperately it will get bigger and more obvious. Tap tap tap. Tap tap tap tap tap. I’m merely delaying the inevitable, though. At some point I will have to attempt to pierce his skin and insert the needle.

‘Just do it, please,’ he says through gritted teeth.

I stare at the vein, now so enlarged by the tourniquet I feel certain I won’t miss. Just push it through the skin, I tell myself. One quick movement.

‘Sharp scratch!’ I bellow enthusiastically and, trying not to think too much, I plunge the needle directly into the vein (I hope).

And wisdom to know the difference …