A schoolboy shadowing his cardiologist father has devised a way for surgeons to leave an internal “code” to make future operations safer. The system would involve using knots in the wires that hold the sternum back together after the operation.

16-year-old Ben Wald was on a work experience placement, a form of short-term internship that most school pupils in the UK undergo. He’d chosen to follow his father David at Barts Heart Centre.

Ben’s idea was designed to tackle the problem of surgeons not always having access to patient records, increasing the risks of repeat surgeries. At Barts around one in 10 patients have previously had a cardiac graft. That’s a part of heart bypass surgery where a vein or artery is grafted on to the heart to reroute around a blockage. Knowing whether and where grafts are already present makes future operations considerably safer.

The problem is that it’s not always easy to find such grafts through X-rays before opening up the patient, leaving surgeons relying on medical notes. However, with around one in six of the Barts patients who had a graft, the notes weren’t available. This can be because the original operation was overseas, carried out too long ago, or simply that there’s a problem retrieving the notes in a situation where there’s no room for delay.

Heart surgery involves breaking open the sternum to access the heart. After surgery, a series of relatively sturdy wire loops holds the sternum back together so it can fuse back naturally; unlike with stitches, the loops remain in place permanently. Ben’s idea was to use these wires – which do show up easily in X-rays – as a code.

The idea is that the top wire (nearest the clavicle) would be placed pointing upwards – which is not usual practice – to indicate that the code was in use. The wires below would point to the left or right to indicate the number of grafts, with the direction showing if a graft started from the subclavian artery or aorta. A wire pointing straight down would show the code had ended and that any wires further down were not part of the code.

The code itself was something of a joint effort. Ben explained that “I asked a question about whether the wires could be sculpted into letters and was mocked a bit. It was slightly implausible.” David then developed the idea into the finished code.

Some surgeons at Barts have already begun ‘writing’ the code after operations and hope to publicize it so that other surgeons know to look for it.