Renowned cardiovascular and cardiothoracic surgeon, and chairman and managing director of the Medanta Medicity Hospital in Gurgaon Dr Naresh Trehan on Tuesday said that senior Congress leader Vidya Charan Shukla continued to be in a critical state medically, though he has shown slight improvements in the past 24 hours.

"He seems to have showed some improvement with respect to kidney function etc. However, given his age and the trauma that he has gone through, we have to be very cautious," Dr Trehan said.

He also expressed hope that Shukla will show some definite improvements in next 24 to 48 hours. "Hope that there is more improvement in his condition in the next 24 hours. But it is too early to say he is out of danger," he said.

The 84-year-old former union minister sustained three bullet wounds after he was caught in the middle of an ambush by Maoists on a Congress convoy in Chhattisgarh's Bastar District on Saturday.