At 7am, in the dark, luggage in hand, it’s like arriving at an international airport. The main concourse is brightly lit with shops and a cafeteria. But it’s not the departure lounge we’re heading for, it’s the hospital operating theatre — although general anaesthesia is a departure of sorts. We are put in a small side room with some other couples to sit and wait. After a while there are drips of conversation: “Knee?” “Same here.” Pause. “Hip?” “Me too.” Outside on the ward, behind one of those curtains that screen doctor and patient from view, I hear: “How old are you?” “Well, now you have me.”

My guts grumble insistently despite a decent breakfast. I entertain the thought that they are in a mood of rebellion. The enteric nervous system, the “brain in the belly” that regulates the functions of the gastrointestinal tract, is built from the same sorts of nerve cells as the brain up top, a hundred million of them, with the same general functions: input, output and inter-neuronal crosstalk. It has complex neural circuits capable of learning and storing knowledge, and a remarkable degree of functional independence. Sever its links with the mainframe in the skull and it will carry on regardless. So, why not a primitive mind of its own? Get on with it, it’s saying, or get us out of here. It’s the same in tedious committee meetings.

At intervals people are plucked out of the room by nurses and anaesthetists for their pre-op routines. They return in hospital gowns, faces a tad more strained. The porter arrives to take my wife away at 9.20am. He looks at her luggage. “Blimey!” he says. “Here for your holidays?”

I’m at my desk by 10am, trying to work while the surgeon slices my wife’s flesh and hacks at the cancerous bone. Orthopaedic surgery is closer to butchery than any other branch of the profession. At 1pm I call the ward. She should be out of theatre by now but isn’t, nor by 2pm. The brain in my belly sends pulses of worry up the information superhighway of the vagus nerve (the so-called “nerve of compassion”) and into my head. But by 3pm all is well. My wife is back on the ward, way up on the 11th floor, with a splinted thigh, a new hip, a morphine drip and a view of the sunlit moors. I sit at her bedside reading the sports pages as she drifts in and out of sleep. Then the surgeon turns up to tell us that he is pleased with his work. He’s cheerful and uplifting, leaving us tearful with relief.

In the evening, back home, I try to settle to work but the brain in my belly fancies a beer and I’m not arguing. That night, the woman who doesn’t know how old she is gets up and looks for her husband. He must be somewhere in the hotel. An amputee screams with night terrors and the nurses go about their business. I have my low-flying aeroplane dream. I’m in a cavernous airliner, seeing trees and rooftops perilously close. We’re losing power, dropping ever lower. One of these days we’re going to crash, but not yet. The thing is to try to enjoy the view.

The author is senior lecturer in psychology (clinical) at the University of Plymouth