A hospital consultant who helped to hasten the deaths of two dying premature babies was cleared of misconduct by the General Medical Council yesterday.

Michael Munro, 41, a consultant neonatologist at Aberdeen maternity hospital, injected a large dose of a muscle relaxant into the babies moments before their deaths in 2005 to ease their distress.

In an act which the GMC said was tantamount to euthanasia, he injected 23 times the recommended dose of pancuronium. However, a disciplinary panel in Manchester found his fitness to practise was not impaired by his actions. The hearing was told that both infants, Baby X and Baby Y, suffered violent spasms in the final throes of death and both appeared to be very distressed. The condition, known as agonal gasping, often occurs when treatment has been withdrawn from the terminally ill.

The babies' parents knew what he was doing and that the injection would relieve their suffering and hasten their deaths.

Dr Munro administered a huge 2,000mg dose of the muscle relaxant, which stopped the babies breathing, and they died a short time later. The fitness to practise panel decided the doctor had administered the drug to relieve the children's suffering rather than hasten their death, although this had been an expected consequence.

The panel rejected claims that his actions were inappropriate and fell below standard, as there were no specific professional guidelines.

After the hearing, Dr Munro said: "I very much regret any distress that has been caused to the parents by these proceedings. I hope that today's decision will promote further consideration of the treatment of neonates and end of life decision-making and that this, in turn, will lead to clearer professional guidance."

Roelf Dijkhuizen, medical director at NHS Grampian, said: "The treatment was not part of accepted practice and therefore, following a thorough investigation, the decision was taken to refer Dr Munro to the GMC. We note the findings of the panel and agree with their view that Dr Munro's actions were taken with the best interests of the babies in mind."

Dr Dijkhuizen said that following the incidents, a protocol for all end of life decisions had been put in place to comply with guidelines. He believed the measures would avoid similar incidents in future.

The chair, Jacqueline Mitton, said the panel accepted that Dr Munro had administered pancuronium believing that the babies' distress could not be relieved by morphine. "Having regard to the lack of clear, specific professional guidance and that it is undisputed that your intention was to relieve suffering rather than to hasten death, the panel is satisfied that at all times you sought to act in the best interests of each baby."

The parents did not wish to comment.