Calcutta, March 22: State CPM secretary Anil Biswas’s blood pressure became unstable for a while last evening. His overall condition continues to be critical.

Biswas suffered a massive brain haemorrhage on Saturday evening and was admitted to a private hospital.

“There has been a slight setback and his blood pressure was unstable for a brief period last evening,” today’s medical bulletin said.

The chief minister went to see Biswas this evening.

The CPM leader is on ventilation and the last CT scan yesterday showed that the clot in the right of his brain persists. “The clot is there and it will take time to go. It might take few weeks,” said Jayanta Basu, one of the doctors treat-ing Biswas. “However, there is no plan for another surgery on his brain at present.”

According to doctors, the pressure also fluctuated this afternoon, but became stable soon. “In such physical conditions, these problems are expected and that is why a patient is kept on ventilator and requires round-the-clock monitoring,” a doctor said.

According to neurosurgeons, in case of a brain haemorrhage, the clot can stay for months. “The problem is, the longer the clot persists the more the damage to the brain and there is no way of taking it out other than by medicine,” a doctor explained.