Separating conjoined twins is a stressful, high-risk operation. It's why I went into medicine

I’ve been involved in thousands of operations as an anaesthetist, but none like the one that started on a seemingly ordinary Monday morning back in February. I was part of the team at Great Ormond Street hospital that separated very rare craniopagus (joined at the head) conjoined twins.

I first heard about the case around a year ago. A pair of twins from Chārsadda, Pakistan had been born fused at the head, which is an incredibly rare condition. We got funding for the operation and the girls, Safa and Marwa Ullah, came over to London for treatment when they were 19 months old.

It was a six-month process, with three major operations, to separate them. Conjoined twins are always rare, and ones who are joined at the head even more so. They’re really challenging cases and it’s a good opportunity for us at the hospital to work as a team.

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We were dealing with two patients rather than one, and it was a massive undertaking. More than 100 people were involved – from the nursing staff on the ward to those in the theatre, anaesthetic staff, healthcare assistants, radiographers, radiologists, the people who make the 3D models, medical physicists and more.

The operation to separate conjoined twins is very high-risk. If they’re joined at the head, one twin has most blood vessels going into the head, while the other one has a lot of drainage. All the connections have to be divided separately and over a period of time, so the twins can develop a circulation for themselves.

Before the last operation I felt a massive sense of anticipation and got an early night. I knew it was going to be a long, busy day and I wasn’t sure what time I’d be back home. We start work at 7.30am, and not one of those operations finished before 1.30am the next morning. One of them lasted for 24 hours.

People who have never worked for 24 hours can’t understand how you concentrate for that long, but the human body is amazing. Your natural adrenalin keeps you going: it’s not sustainable for any longer and you can’t do mundanity for that amount of time, but this was a one-off occasion. A couple of nurses and I shared a cab home and we were monosyllabic; the next day I was absolutely exhausted.

When the twins arrived in the theatre for the final operation they each had their own team looking after them. Everything from the outfits to equipment was colour coordinated, with red for one twin and blue for the other. Their mother said her farewells knowing that when she next saw them it would be 10pm and she would hopefully have two healthy, completely separate children.

When you do an operation that you’ve done many times before you know what’s going on. This, though, was a new experience for most of us and the tension in the operating theatre was high.

During the very long operation, there was one point in the middle of the night where one of the twins became very unstable and had a really strange heartbeat for about 45 minutes. That was stressful. If they went on to have a cardiac arrest and died, the other one would also die. That was very hairy and we sent the surgeons away until we reached a period of stability. I was thinking: ‘I really, really, really hope we get through this. I hope we’re not going to lose them. That would be devastating, just awful.’ Luckily they became stable again and we got the surgical team back in.

When the last connection between the twins was separated there were two individual patients, and each twin was no longer dependent on the other for their survival. It was a momentous, amazing moment and the whole room felt it. It was a very weird feeling when I saw these children who came as a unit now as two individual people.

As soon as they were separate, the surgeon put a swab on the open wound and they were transferred to another operating theatre. Everyone had this feeling of real excitement, awe and amazement. The twins’ day was done and they wouldn’t wake up until the next morning, but there was one important thing left for me to do.

I walked into the family room to tell the mother everything was fine. She cried, which is understandable – we were all emotional. Her husband died when she was pregnant and it must be very difficult to be the parent of any sick child, let alone in another country where you don’t speak the language.

This type of operation is not something you do every day. The NHS is quite a hard place to work at the moment and being able to do this was such a wonderful thing. This is what I came into medicine for and I’m so lucky to do this as a job.

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