Effortlessly and silently, Henry's bed slid down the empty, sterile corridors towards the operating centre. There wasn't another living soul in this sector of the building, but still the sensors in the walls and ceiling bleeped quietly as he passed, checking his bacterial levels, ready to trigger the elimination of any organisms he might cough up and leave in his wake.
Henry himself, of course, was unaware of his solitary journey, no sympathetic nurse to hold his hand or flash him a reassuring smile.
The robotic bed in room 119 had received the computerised instruction to take Henry to surgery around 3am, while the patient was in a deep sleep. It had administered a sedative intravenously through the tube in his arm and was monitoring his state of consciousness, as well as the habitual heartbeat, pulse and blood pressure checks. If Henry began to surface, the dosage would increase automatically.
The bed neatly docked in the operating centre, locking itself into the floor in the middle of the room and adjusting its height and angle for the video monitors. Two hundred miles away, Frost, the anaesthetist, swivelled in his chair, took a swig of coffee and a last glance at the bowel operation he had been monitoring and turned his attention to Henry's heart-rate.
Frost put on a pair of glasses which projected Henry's patient notes above the prostrate and unconscious form he could see on his screen. He frowned.
This man was 60 - now regarded as middle age. He had spent a dissolute youth by the standards of the mid-21st century. Had he - and the medical authorities - known from birth that he had a gene predictive of heart disease, he would never have been allowed to gorge himself on a high-fat animal protein diet in his youth. His fridge would have been programmed not to order up the butter he used to lavishly spread on his toast. He would have aerobic machines installed in his home. These days a young man with such genes knew that no employer would look at him without a high-grade daily exercise certificate. And this man used to smoke! Of course, he was forced to give up when cigarettes were finally banned 10 years ago but, to judge from the state of his arteries, he had probably been buying them on the black market.
Similar thoughts were running through the head of the surgeon on the other side of the world, but Jenner was in a happier frame of mind. It was not so often that he had an opportunity to exercise his judgment any more, with the hugely improved health of the western world's population. Surgical skills - the speed and agility that used to be crucial to the success of an operation - were a thing of the past. Surgery had ceased to be hands-on.
At his control screen, he checked that Frost had finished anaesthetising Henry, and began to instruct the robotic arms in the operating centre far away in their task. There would be no opening of the chest - those days were long gone - just a tiny incision to allow in the microscopically small instruments and minute cameras that would do the work. Henry would be up and about again in a few days.
Almost all of the scenario described is possible already. Dr Charles Wilson, from the Institute for the Future and the department of neurosurgery at the University of California in San Francisco - a man, in fact, licensed to work out ways of making the extraordinary happen - says the intelligent bed is already with us and the robotic, sensor-filled hospital is on the drawing board. And it's most likely to happen in California first.
"Entirely because of the seismic regulations in California, many of the hospitals will have to be either substantially changed or replaced, so there's an opportunity in California to look to the future in building hospitals," he says.
So they are thinking in radical terms - where can you do it if not in California, which has good geological reasons for discarding the "social, economic and religious trappings", as he put it, that cause people to put up such a fight against hospital closures? "The hospitals are becoming smaller for the same patient population and the patient population is becoming more acute," says Wilson. "All the rooms can be instantly converted into ICUs [intensive care units]. It makes sense.
"Patients go to ICUs so they can be monitored and have someone constantly looking at their blood pressure and so on. If these things can be done by sensors, they could be put in any bed and there would not be a need for a centralised ICU where patients can get cross-infections."
And so to that bed. The US army has been using it for some time. It was designed for field hospitals - a bed that can be used as a trolley and a stretcher and a life support system, incorporating all kinds of monitors.
The rapid advances in robotics and sensors will allow ever more sophisticated versions to be developed for hospitals. Once the patient is fixed up with drips, masks, suction tubes and whatever else, computers can control and monitor breathing, pulse, blood pressure, drug doses and the rest. There will be no need for a nurse at the bedside. Henry and half a dozen others can be monitored in their private rooms from a central control panel, perhaps within the hospital but equally possibly hundreds of miles away. Telemedicine is already here.
Better health all round will mean fewer people with more serious problems - and those who need treatment outside the home will probably visit a specialist heart, lung or brain hospital. It is now widely accepted that the busiest surgeons, who perform the same operations again and again, are the best at them.
"There's a hernia hospital in the United States that does nothing else, but does it better than anywhere else in the world," says Wilson.
The future of medicine holds amazing developments, such as the growing of human organs. Wilson envisages hospitals with "a whole menu of solid organs and tissues and cells", some of which may come from specially bred animals, like the genetically modified pigs produced in Cambridge in Britain.
One of the reasons we will not need the massive, all-purpose gen eral hospitals of today, where you can get a splint for a broken leg, antibiotics for meningitis or have a brain tumour extracted, is that people are not going to get into so many serious health crises in time to come. Diabetics will be fitted with a smart glucose sensor which can detect glucose levels through the skin without the need to draw blood - the prototypes already exist. People with HIV could be fitted with a viral-load sensor in the same way. Both sensors would be integrated with reservoirs implanted under the skin containing medication, so that any problems can be managed instantly. High blood pressure and irritable bowel syndrome could be treated in a similar way.
But the biggest revolution will flow from the decoding of the human genome. Medical treatment in the next century will move from diagnosis and treatment to prediction and prevention. Each of us will be in possession of a gene chip - our own personal DNA code. Every doctor's surgery will have sophisticated software that can read it. From birth, we will know our inheritance - the likelihood of heart disease or certain cancers. We will know what to do to minimise the risk. The downside is that the information could become available to employers and insurance companies. On the upside, our doctors - or rather their computers - will know what doses of which drugs will be most effective in the event that we do get sick. How well any medicine works on an individual will depend on his or her genes.
It is a brave new world that has such healthy people in it. But how far into the next millennium will we be before the poorest of the world's people get even a taste of any of this? The enormous expense means it will be available for a considerable time only to the rich with private medical insurance in the right parts of the US. As Wilson says: "The future is always among us. It is not well distributed or diffused."
But the doctor predicts that, however slowly in some places, this kind of hi-tech medicine will become the norm. "My guess is that it will come faster than you might think."
The reason for that is public demand. If this futuristic technology will save and prolong lives, it is going to be difficult for the politicians to think of a money-saving argument.
