Martin Leck, 34, wasn’t breathing when detention officer Jacqueline Corner made a check on his wellbeing following his arrest for being drunk and disorderly, an inquest heard.
Despite frantic attempts by police staff and paramedics to revive him, his life could not be saved.
Mr Leck, who was a chronic alcoholic and also suffered from epilepsy, had been placed in a police cell at 8.25pm on the night of his death on Friday, March 22, 2013, with a decision made that observations should be made every 15 minutes.
When the detention officer carried out her observations at 10.02pm - 22 minutes after the last check - she couldn’t wake Mr Leck.
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The dad-of-two, of Imeary Street, South Shields, was the equivalent off seven times over the drink-drive limit when he died.
Home Office pathologist, Dr Jennifer Bolton, had earlier told the inquest that Mr Leck’s cause of death was acute alcoholic poisoning.
He was transported to South Tyneside Hospital but was sadly pronounced dead at 11.44pm.
Denention officer Corner said there was a degree of flexibility in observation to checks in order that each detained was visited on the hour - such as fifteen minutes or haldf past a certain hour.
She said: “When Martin came in he didn’t present any incapabilities at all. He just wanted to go to sleep.
“I carried out my first check at 8.50pm and had no concerns at all. I got a good response.”
The officer said she shouted out for help when she couldn’t wake mr Leck little more than an hour later.
She added; “I went in the cell and shook him, but he was not responsive. I shouted for the custody sergeant. He asked me to see if I could get a pulse on Martin’s neck, but I couldn’t.”
The inquest continues.