Two thousand kilometres from the scalpel, a surgeon feels the kidney give way

In an operating theatre in Qingyuan, northern Guangdong, a 70-year-old man named Liu Dashu lay under the arms of a surgical robot. The hands guiding those arms belonged to Dr. Hu Hao, sitting at a console in Beijing, more than 2,000 kilometres away. The signal between them took 42 milliseconds to travel, and it never wavered.

The operation was a nephroureterectomy: the removal of a kidney, the entire length of the ureter and a cuff of the bladder wall. It is the standard treatment for upper tract urothelial carcinoma, and it is an awkward candidate for remote work. The surgical field stretches from the flank down into the pelvis, which usually means repositioning the patient partway through and re-docking the robot around him.

It took under two hours. Blood loss was minimal, the vital signs held steady. The next day Liu Dashu drank water and walked.

Hu described the experience afterwards in the flattest possible terms: no perceptible lag, a sense of presence equivalent to standing at the patient's own bedside. That sentence carries the weight of the whole enterprise. Research on telesurgery holds that delays under roughly 100 milliseconds pass unnoticed by an operating surgeon, and that performance falls away past about 300. At 42, the distance had effectively been deleted.

The line from Strasbourg

The ancestor of this operation ran the other way across an ocean. Jacques Marescaux of IRCAD sat at a console in a Manhattan building and removed the gallbladder of a 68-year-old woman lying in a theatre in Strasbourg, over a dedicated fibre-optic line. His team called it Operation Lindbergh, after the first solo Atlantic flight, and they had fixed 330 milliseconds as the delay at which they would stop and hand the patient to the surgeons in the room. The mean round-trip delay came in at 155.

China's version restarted on mobile networks. A neurosurgeon in Sanya implanted a deep brain stimulator in a Parkinson's patient in Beijing; an orthopaedic surgeon in Beijing directed spinal screw placement on patients across several provinces in a single sitting. The robots have since become domestic — MicroPort MedBot's four-armed Toumai system in Shanghai, the Kangduo system out of Suzhou — and the reach has stretched to roughly 12,000 kilometres, from China to Morocco.

Qingyuan is a city of some four million people spread across mountainous country north of Guangzhou, taking in the Yao and Zhuang autonomous counties. Its main referral hospital now has, on certain days, a urologist from Beijing.

There is a symmetry worth holding onto. Peking University People's Hospital, where Hu sat at his console, opened in 1918 as the first hospital in China financed and run by Chinese doctors. Its founder, Wu Lien-teh, had stopped the Manchurian plague with a gauze mask he designed himself.

No perceptible lag; the sense of presence equivalent to operating at the patient's actual bedside.