‘‘This is a once-in-a-lifetime operation that teams would do,’’ Mr Donnan told reporters outside the hospital. ‘‘There really still is a long way to go,’’ Mr Donnan said. ‘‘The girls have a very difficult time ahead of them. ‘‘For the hospital, it is a historic moment and, for the girls, an even more historic moment.’’ The operation went for longer than would have been expected, Mr Donnan said.

He said the staff had taken planned breaks and the twins were well nourished before the operation. The mood inside the operating theatre had changed following the separation, Mr Donnan said. ‘‘It’s been a very nice stage to move into,’’ he said with a smile. Surgery to separate Trishna and Krishna began yesterday morning. Anaesthetist Dr Ian McKenzie told reporters earlier that concerns over problems with Krishna's kidney had eased.

The orphans were given just a 25 per cent chance of making it through the operation without harm. The hospital's experts considered some level of brain damage a 50 per cent chance, and death was also a significant possibility. However, surgeons were quietly confident yesterday afternoon, saying all the signs so far had been positive. ''Everyone was particularly optimistic and excited,'' said plastic surgeon Tony Holmes. Earlier operations to separate blood vessels shared by the twins had been a success with no new major connections appearing. ''If the blood vessels started to reconnect we would end up with pressure problems, but those connections didn't seem to be major,'' Mr Holmes said.



At 8am yesterday the unconscious twins were wheeled into an operating theatre usually used for heart surgery and placed face-down on two connected operating tables. For the first two hours anaesthetists worked to get the twins to the point at which surgery could begin. ''There's a lot of mucking around at the beginning of an operation like this,'' Mr Holmes said. ''[It's] mainly for positioning and getting all the tubes right so there's no pressure on the eyes, no kinks in the tubes. Once they're covered up, the anaesthetists have very little chance of getting in. So that took quite a while, but eventually we got knife to skin at about 10 o'clock." Plastic surgeons then took over, led by Mr Holmes and Andrew Greensmith, stripping back the skin that had grown over plastic extenders in order to fit over the twins' finished heads. The cuts followed a careful curve so that when the skin was folded back over it would match the shape and hairline of the new skulls. Midway through this process, Mr Holmes said the skin was healthy and ready for its eventual closure many hours later. About 1pm the neurosurgeons took over, cutting into the skull to create a three- by 20-centimetre ''window''.

Surgeons Wirginia Maixner and Alison Wray began the intricate work of separating the blood vessels and the brain matter that still linked the twins, while retaining enough of the bony bridge to keep the area stable. ''It's step by step going through it,'' Mr Donnan said. ''You can't speed it up, you can't slow it down." After the neurosurgeons finished, the plastic surgeons would return, closing the brain lining and skulls with artificial caps, then closing the skin.

Mr Donnan said the teams were used to long hours and complex problems - what was new was doing several operations-in-one on two connected patients. Up to 16 surgeons came and went during the operation, although only a couple could work at a time.

The biggest unknown would be when the twins' systems were separated for the first time, and their blood pressures stabilised to a new level and their bodies adjusted to a new ''dynamic'', Mr Donnan said. After the operation, the children will go to intensive care. Brain scans over the following 36 hours will indicate when to make an attempt to wake them. Loading But it could be weeks before it is clear whether the surgery has been a complete success. Atom Rahman, from the Children's First Foundation charity in Bangladesh, was at the hospital to see the culmination of the work that began when he arranged for the twins, who turn three next month, to come to Australia. Atom Rahman, from the Children's First Foundation charity in Bangladesh, was at the hospital to see the culmination of the work that began when he arranged for the twins, who turn three next month, to come to Australia.

- with AAP

