NO-ONE will ever know for sure why a student went to sleep and never woke up.

Ciaran Smith, 21, was visiting a friend in Southampton and was found dead sitting in a chair after an evening spent drinking.

But the inquest heard that Mr Smith’s alcohol level was less than twice the drink-driving limit and far below what is normally associated with alcohol poisoning.

Mr Smith, a student from Ruislip, west London, was visiting schoolfriend Laurence Jones at his house in Wilton Avenue, Polygon, last November.

They went to a party with friends, where Mr Smith, and returned at around 3am on November 4.

In a statement, Mr Jones said they had gone to sleep and he had woken at around 9am to see Mr Smith motionless and with his head on his chest, seemingly asleep.

Later at noon Mr Jones got up and, seeing his friend in the same position, approached him. “I shook him, he was pale, stiff and cold; his lips were blue.”

The emergency services were called and Mr Jones carried out CPR on his friend but paramedics could do nothing to save him.

PC Guilia Puccini, based at Portswood station, was first officer on the scene. Police said there were no suspicious circumstances.

Consultant histopathologist Adrian Bateman conducted a post-mortem. He said there was no evidence that Mr Smith had choked on vomit, nor were there any illegal drugs or injuries.

He said the way Mr Smith was sitting, leaning forward, may have obstructed his airway and affected his breathing but he could not be sure.

Senior coroner Grahame Short recorded an open verdict. “I cannot be satisfied he died of natural causes, as a result of alcohol or any other unnatural cause. We never will know why Ciaran died.”