I've never liked the idea of anaesthesia: it's something I vowed never to go through after watching my father react badly to three operations. He became agitated and was ranting and raving – it was terrible to see. So when I had to have an hour-long operation for a hernia, I wanted to take another route – stay awake during the procedure.

As a hypnotherapist, I've helped hundreds of people train their minds not to register pain; now I had an opportunity to try it for myself. In fact, part of me had been hoping for a chance to practise what I preach. But another part couldn't help but think, "I hope it works."

I had used self-hypnosis to reduce back pain after an injury, but never for an operation, so this was going to be a first. I knew my main obstacle was fear. The aim of self-hypnosis is to send suggestions or instructions to your subconscious to feel a certain way: confident, relaxed or, in my case, pain-free. Fear acts like a negative instruction, undoing all your hard work and disrupting positive messages.

I knew that being sliced open is painful, but had heard that the real agony is when the scalpel cuts through the peritoneum, the layer of tissue protecting the organs. Could self-hypnosis really control this pain?

I also had to contend with the possibility of the surgeon's fear. Your mind is a powerful thing, but another person's mind is also a big influence: if he was sceptical about my abilities and not 100% sure that he wasn't going to inflict pain on me, the surgery would be compromised. He had to have as much faith in my ability to block out pain as I did.

Luckily, I had worked with the surgeon in a professional capacity, so he was fine to perform the operation on me without chemical anaesthesia.

Before I was wheeled into theatre, I spent 15 minutes preparing myself mentally, programming my brain to turn off the pain responses. When fully awake, your mind is logical and rational, but while hypnotised you become more intuitive, emotional and open to suggestion. It's as if your conscious mind is no longer in the driving seat. Even as an experienced hypnotherapist, I had to be very firm with myself to stop fears creeping in, especially when I saw all the surgical instruments lined up in the theatre.

I told myself that, as the surgery progressed, I would feel more and more relaxed and my groin would feel numb to everything except touch and pressure. I repeated this to myself and felt myself drifting off.

But as I lay on the chilly, plastic-covered mattress of the operating table, my back began to twinge. I was worried the backache might distract me and was about to ask for a cushion when the surgeon made his first incision. This meant I wasn't fully in my hypnotised state, but even so I didn't feel a searing pain, just a minute amount of discomfort that soon disappeared as I re-established my own pain-killing thoughts. As the surgeon opened up my abdomen and stitched together my muscle wall to hold in my intestine, I let my thoughts drift, constantly repeating messages about numbness.

I could hear the surgeon speaking, but kept my eyes closed to focus on my own thoughts. I could feel his hands rummaging around inside me, which wasn't a pleasant feeling, but not painful. It was a legal obligation to have an anaesthetist in the room, in case of emergency, but all he did was monitor my vital signs, which stayed practically normal throughout.

Afterwards, I felt relieved that it was over – I hadn't felt the tiniest twinge of pain. I was offered painkillers, but it would have been strange to need them after what I had been through without them. Instead, I continued sending numbing thoughts to the area. I went home the same day, albeit walking gingerly to avoid tearing the stitches, and by the evening I was back at my desk.

After conventional hernia operations, people can suffer for weeks, in intense agony when moving, coughing, even sneezing, but I felt fine. I did feel a little stiffness the next day, but this was good because it reminded me not to exert myself. All I felt was a light tingling around the scar, which I found pleasing: I knew my body was healing painlessly.

If I need surgery again, even heart surgery, I would definitely opt for self-hypnosis, as long as the surgeon was agreeable to it. I know my mind is powerful enough to prevent any pain, and that's a wonderful feeling.

As told to Emily Cunningham

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