Last October, David Lee, a retired engineer from Hampshire, went into the Royal Brompton Hospital for a heart bypass operation. It was a striking success. Normally bypass patients take six to eight weeks to recuperate: within a fortnight, the 63-year-old had resumed his regular three-mile morning walk.
It wasn't just Lee's rapid recovery that was exceptional. The surgeon in charge of the operation, Anthony De Souza, sat several feet away from him during the procedure. The arms that delved into the patient's body were not his. Instead, they were made of metal, and bolted to the table.
Lee was one of the first people in Britain to be operated on by a robot that is capable of carrying out the most delicate aspects of the surgeon's art in the confined space of the chest cavity, and with the minimum of damage to the chest itself.
The robots are expensive - around three-quarters of a million pounds each - and rare. There are just two in Britain, and only a few dozen in the whole world. But for heart bypass patients, they offer a huge advantage.
About 30,000 bypass operations take place in Britain each year, a number the government wants doubled. The procedure is actually a series of operations: first, veins or arteries are snipped out from other parts of the patient to replace the failing coronary arteries, blocked by fatty deposits or blood clots.
The surgeon then takes an electric saw, cuts down the middle of the patient's breastbone, and opens up the ribcage like the lid of a box. A cold potassium solution is injected into the heart to stop it, and the business of pumping and oxygenating the patient's blood is taken over by a heart-lung machine while surgeons graft in the good vessels.
When this is finished, the heart is restarted, the inside of the patient cleaned up - anticoagulants administered to keep the blood flowing freely make the inside of the chest a messy place - and the breastbone is wired back together. Given the radical nature of such a procedure, it is extraordinary how routine it has become: it is the most commonly performed heart operation in Britain.
A bypass literally rejuvenates its beneficiaries. But there are drawbacks. The opening and resealing of the chest means a long, often painful recovery period, and in a minority of patients, the use of the heart-lung machine leaves behind tiny bubbles and particles in the bloodstream. These can diminish the person's ability to carry out certain mental tasks, such as maths problems.
So two solutions were needed: a technique to avoid opening up the chest, and a way to avoid using the heart-lung machine. In the 70s, doctors in Latin America solved the second problem. Faced with the impossibly high cost of heart-lung machines, they developed a way of operating on a still beating heart. The device they used, called a stabiliser, immobilised only the small section of the heart being worked on.
And now, with the robot, the first problem has been solved. For a few lucky patients, there is no need to bisect the breastbone. Instead, the two arms of the robot slip in between the ribcage through holes that are smaller than a five-pence piece.
Six holes were made in David Lee - two for the robot arms, one for the camera and light, two for drainage and one for the stabiliser. The word "riddled" comes to mind, but each hole was an easily healed incision.
"I've been left with just small scars," Lee says. "I had very little pain when I woke up, and I'd recommend the operation to anyone. It makes such a difference to your life."
De Souza, who is pioneering the use of surgical robots in Britain with fellow Royal Brompton consultant John Pepper, says: "The fewer holes the better. But they heal so well that you shouldn't think about jeopardising the outcome by using too few of them."
Although the surgeons are as comfortable with the word as the media, "robot" is a misnomer. The machine is really a slave, following the movements made by the surgeon sitting in another part of the operating theatre, and translating movements of centimetres into fractions of millimetres.
Zeus, the make of robot at the Brompton, is an easy workmate. When off-duty, it sits quietly in a small, shabby room. It doesn't draw a salary, never uncorks a bottle of wine, always stays on the hospital premises and, though it has a voice - an American female one - has never been known to criticise a colleague.
The set-up is in three parts: the operating table, with the robot arms and camera attached; the separate computer brain of the system; and the workstation where the surgeon sits. At first the human surgeons watched what they were making the robot do through eyepieces that gave a three-dimensional view, but now they use a conventional flat screen.
Sitting at the workstation, the surgeon holds a control in each hand, tweezer-like instruments that are attached to rods which transmit movement through all axes to the robot.
Staff have set up a practice system for surgeons to hone their robot suturing skills. A cardboard box stands in for the chest cavity; the robot arms and camera plunge inside through holes. For muscle and artery, there is a rubber glove, stretched taut and marked with lines of dots where the stitches are supposed to go.
De Souza pops in a couple of stitches, and invites me to have a go. I sit down and grasp the tweezers. On screen I can see a pair of metal pincers, a needle and thread, and the line of dots. Everything looks huge, but the pincers are only a couple of centimetres long. I engage the system by pushing on a treadle with my foot. Press the tweezers, and the pincers open; move and twist them, and the robot obediently follows. I attempt to stitch. I gouge a hole, then lose the needle. In a real operation, I would be wrestled to the ground and taken into custody, but for a trained surgeon, the system is easy to pick up - as the rows of neat stitching in other practice gloves testify.
The robot surgeon was commissioned by the US department of defence for use in remote field hospitals. However, its use in the US is still restricted by the food and drug administration. Europe has been the test-bed - so far, apparently, with success.
In bypass operations, the robot can only deal with the replacement of a single artery - the critical left anterior descending artery. The average number of arteries replaced is three, and single-artery problems are often dealt with by other, temporary means, such as a balloon inflated at the blockage site - a process known as angioplasty. But De Souza says some surgeons are arguing that single-artery bypasses should be performed more often.
One of the drawbacks of the robot is that the human surgeon cannot feel the yield and texture of the tissues being cut, sewn or probed. The team working with Britain's second surgical robot, at St Mary's hospital and Imperial College in London, are trying to devise just such a feedback mechanism.
St Mary's has been using the robot, known as da Vinci, for bowel operations and plans to carry out its first heart bypass later this year. The lead consultant on the project is Ara Darzi, professor of surgery at Imperial.
"Using the robot is straightforward, natural and intuitive," he says. "It's absolutely wonderful - like doing an open operation but doing it closed. It's probably the most ingenious piece of mechanical engineering I've ever seen."
