A sat nav fault which delayed an ambulance getting to the home of a nine-year-old boy who died after a severe asthma attack "made no difference whatsoever", a coroner said today.

Corey Seymour went into cardiac arrest on the front lawn of his home in Bromsgrove, Worcestershire, after a "sudden and catastrophic exacerbation" of his asthma, an inquest heard today. An ambulance took 24 minutes to reach the schoolboy and he was pronounced dead shortly after arrival at hospital. It later emerged that the ambulance's satellite navigation system had sent the crew in the wrong direction on the way to the call out, leading Corey's mother, Melanie Carver, to question whether her son could have been saved if he had received hospital treatment sooner.

The inquest, in Stourport-on-Severn, Worcestershire, heard that paramedic Richard Perrins was at the scene in a rapid response car within five minutes of Miss Carver dialling 999 at 8.22am on September 13 last year. The ambulance arrived at 8.46am, having been delayed by around two and a half minutes by the sat nav problem.

Worcestershire Coroner Geraint Williams, who ruled that Corey died from natural causes, said: "Would the outcome have been any different if the ambulance had arrived two and a half minutes earlier to the scene? "In my judgment, no."

The coroner, who described the case as "just ghastly", found Corey had gone into cardiac arrest around seven or eight minutes after his mother's 999 call. He said: "At that point everything was against Corey and he would not have survived." He added: "This was a young lad who had had a very severe exacerbation of his condition at home. "In my judgment, within a very short time he had a cardiac arrest ... he would have had that cardiac arrest before he got to hospital even if Mr Perrins had decided to take him straight there. "In my judgment that two and a half minute delay in getting to the scene made no difference whatsoever."

Miss Carver told the court Corey had woken her at around 4am struggling to breathe, but had gone back to sleep after using his inhaler. He complained again four hours later but asked for some breakfast. "I went into the kitchen to make him some breakfast and he shouted to say he was getting worse so I rang an ambulance," Miss Carver said, adding that she "was in panic mode" as the emergency unfolded.

Mr Perrins, a West Midlands Ambulance Service paramedic with 44 years' experience, told the court that Corey was "obviously a very, very poorly little boy" and was gasping for air when he arrived at the house. He said he immediately put him on a nebuliser and a cardiac monitor but he did not respond to the treatment and "flatlined" within minutes.

The coroner praised the paramedic for his "impeccable handling" of the situation. He said: "I am satisfied that Mr Perrins provided for Corey the spot-on treatment that was required by him. "It could not, in my judgment, have been started any faster than it was." The court heard that the ambulance sent to transfer Corey to hospital came from a station in Kidderminster because those in Redditch and Bromsgrove - which are both closer - were already out on 999 calls. The coroner said: "There can be no criticism of the ambulance coming from Kidderminster ... it is simply a tragic fact of life."

Nick Henry, general manager for the West Mercia area of West Midlands Ambulance Service, said: "This is a very tragic case and our thoughts remain with the family of Corey. "The coroner has made it clear that there was no criticism of the actions of any of the staff of West Midlands Ambulance Service who attended this incident. In fact, quite the opposite. "He highlighted that the care they gave Corey was spot on. A paramedic was on scene within five minutes of the 999 call and the nearest available ambulance was also sent. "It is true that there was a delay in an ambulance attending the scene due to an issue with the satellite navigation system which amounted to two and a half minutes. "However, the coroner has accepted that the ambulance got there with speed and the delay had no effect on the outcome of Corey's death."

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