What first inspired you to become a war doctor?

Two things. The first was Roland Joffé’s film The Killing Fields, which had a huge impact on me when I saw it as a trainee surgeon. There is a scene in a hospital in Phnom Penh, overrun with patients, where a surgeon has to deal with a shrapnel injury – I wanted to be that surgeon. The second big spur was watching news footage from Sarajevo back in 1993. There was this man on the television, looking desperately through the rubble for his daughter. Eventually he found her and took her to the hospital but there were no doctors there to help her. I thought, “Right, I’m off”.

What was that first experience of war like?

As a young man, jumping off the aeroplane and running for cover, then hopping into a bulletproof vehicle and being taken at high speed to the hospital was Boy’s Own stuff, just how I wanted it to be. It was perfect. The adrenaline was overpowering and the amount of endorphins in your head – I felt like I was floating on air and could do anything. Then to be able to help people as well, having your own operating theatre, it was wonderful. Of course, then I wanted to replicate it all the time. Once I had tasted that, I couldn’t stop.

Is that adrenaline rush still as strong, 25 years on?

Nowadays, I am driven less by wanting to fix individual patients and more by wanting to impart the knowledge and expertise I have built up over the years to local doctors on the ground. I was in Yemen recently and there were simple medical procedures – life-saving procedures – that the doctors were getting wrong because they had not seen them before. Most doctors rarely see war injuries any more. Everybody has forgotten how blast injuries affect children, what gunshot wounds or the shockwave effects of big bombs dropping do to people. That is why it is important for me to keep doing this and why I set up my foundation [the David Nott Foundation] to provide surgical training for doctors from all over the world in how to work in austere environments [war and disaster zones].

What makes a good war doctor?

You have to know a bit of everything – neurosurgery, maxillofacial surgery, chest surgery, abdominal surgery, orthopaedics, plastics, paediatrics, how to deliver a baby. You need to be able to make decisions about what is right for the patient without recourse to hi-tech investigations such as CT scanners, or x-ray machines, which are few and far between on the frontline.

Play Video 2:31 Confessions from A&E: the day Isis burst into my operating theatre – video

How big a problem is PTSD for war doctors?

Really big. I was never quite right when I came back, especially if I had done a two- or three-month mission. I became more irritable and aggressive for a while as I decompressed and readjusted to London life. But it was after meeting Elly and that last mission to Syria that it all became too much. I still very much want to go to challenging places and help people. I have to, I find it almost a calling. But I am more savvy now, I know what not to do. I know when some places are too dangerous to go to.

Would you say you are an emotional person?

Yes, I am a very emotional person. Early on, working in war zones, I did develop this kind of icy heart. I didn’t want any relationships, I didn’t want anybody to get close to me because then I wouldn’t be able to carry on doing what I was doing, and that was all I wanted to do. That is the thing that has changed most about me since having my two daughters.

Are you comfortable being in the limelight?

No, not at all. And I am aware this book will thrust me into it. But I wrote it to bear witness. [My friend] Ammar and the other doctors in Syria said I had to write it because without it, their voices would never be heard and nobody would ever know really what happened.