ONE in ten patients arriving at hospitals by ambulance in the final week of December waited over three hours to be offloaded into A&E departments, new figures reveal.

The latest deterioration in performance comes as the Herald also understands that investigations have been launched in the past week into cases where patients have died in the back of ambulances while waiting for treatment in packed emergency departments.

The Scottish Ambulance Service (SAS) said it was unable to comment, but sources told the Herald that a number of serious adverse event reviews have been initiated since the end of December into incidents where handover delays had resulted in patients deteriorating to the point where they suffered major harm and, in some instances, passed away.

First Minister Nicola Sturgeon yesterday chaired a meeting of the Scottish Government's resilience committee to discuss the "ongoing winter pressures" in health and social care.

A spokeswoman said the Government is monitoring the situation "extremely closely".

READ MORE: Short-term, the focus has to be on staff retention and fixing social care 

SAS statistics for the week beginning December 26 show that 90% of patients brought to hospital by ambulance were handed over within three hours and eight minutes - meaning one in 10 spent even longer in the back of vehicles.

Some areas fared worse. In Grampian, 10% of patients were in ambulances outside A&E for more than five hours and 20 minutes.

In Ayrshire the figure was four hours and 43 minutes; in Fife, four hours; and in Lanarkshire, 10% of patients waited over three hours and 22 minutes.

Sandra Macleod, lead for medicine & unscheduled care at NHS Grampian, said it was facing an "extreme level of pressure" due to the number of acutely ill patients arriving at its hospitals and difficulties in discharging patients to free up beds.

She added: “At all times, cases are triaged, with those facing life-threatening situations being seen rapidly for life-saving treatment, as an absolute priority.”

Joanne Edwards, acute director for NHS Ayrshire and Arran said it was "working closely" with SAS to reduce all avoidable waits, adding: "Despite our staff working hard to assess and treat patients as quickly as possible, some patients have had a longer waiting time than we would wish, and we unreservedly apologise for that."

It comes after figures earlier this week showed that a record 1,925 people spent over 12 hours in Scotland's emergency departments in the run up to Christmas, with the A&E logjam leaving ambulances stranded at the front door.

GMB convener Robert Pollock - a clinical advisor and paramedic based at the Cardonald ambulance control room - said the situation was "horrific" for patients and staff.

He said: "A lot of these patients have dementia on top of their health conditions, and you're trying to sit in the back of an ambulance with them for six seven hours when there's no facilities for them - no toilets - it's undignified.

"They are people, and you can't treat them as people - that's the worst thing.

"No one wants to sit there for hours with a very sick patient when you've done all you can for a patient. It's horrible. The system is collapsing."

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Mr Pollock said paramedics were "lucky" to respond to two or three callouts now in an 11-hour shift where they might previously have attended eight, due to ambulances being stuck or covering a larger geographical area.

He added that even the patients he prioritises as urgent can face lengthy delays.

"People who are very ill with ongoing heart attacks can wait now an hour or more depending where they are in the country because the ambulances are stuck outside A&E. I can't give you what we don't have - all I can do is highlight it and escalate it and hope that someone gets there before it's too late.

"We've got hundreds of jobs on the screen almost every minute of every day."

Median response times for 999 callouts show that, on average, ambulances were reaching 'purple' emergencies - cardiac arrests and severe breathing difficulties - within the target eight minutes at the end of December, although one in 10 cases took over 20 minutes.

One in 10 amber callouts - which include severe chest pain and strokes and have a target time of 19 minutes - took more than one hour and 17 minutes for crews to reach, with 10% of 'yellow' calls taking nearly seven hours.

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Jamie MacNamee, a paramedic in Glasgow and Unite Convener for the Scottish Ambulance Service, said: "Amber are considered immediately life threatening calls, and make no mistake - there's some seriously unwell people in the yellow category as well.

"Without more capacity in hospitals, this will go on and on, but the hospitals just come back to us and say they don't have the estate to create the extra capacity and - even if they did - they don't have the staff to service it.

"We're really in a quagmire here."

A Scottish Government spokeswoman said: “Health Boards are seeing delayed discharges continue to drive up A&E waits, which is why we are working with them to ensure people who do not need to be in hospital leave without delay, freeing up vital beds for those who need them most.

“We are clear that there should be no unnecessary delays for ambulance crews handing over patients at hospitals. NHS staff are working hard to ensure quick and safe handover of patients, releasing ambulance crews back into the community.”