In comes as new figures from Public Health Scotland show weekly A&E waiting times have hit another worst performance on record, with the percentage of patients seen within four hours dropping below 70 for the first time.
Separate figures also published on Tuesday showed a deterioration in performance for the fifth consecutive month.
Dr John Thomson, Vice President of the Royal College of Emergency Medicine Scotland, labelled this “seriously worrying”.
"What we are seeing: ambulance handover delays; dangerous crowding; long stays... put patient safety at risk and can lead to harm or avoidable deaths,” he said.
"Data show that for every 67 patients waiting 8-12 hours, one of them will come to avoidable harm – in Scotland between January and August 2021 there have been 231 excess deaths directly caused by a long wait due to a crowded Emergency Department.
“These are unconscionable practices and both ambulance crews and Emergency Medicine staff are under pressure to resolve the problem.”
A Scottish Government spokesperson said they will engage with the RCEM about their analysis.
Dr Thomson’s comments came as a weekly report from Public Health Scotland showed that in the week to October, 24, just 69.6 per cent of patients were seen and admitted, transferred or discharged within four hours.
The Scottish Government target is 95 per cent.
Some 1948 people waited for more than eight hours, the highest number since records began in 2015.
The number of people waiting over 12 hours was also a record high, at 630.
Opposition politicians said the figures were symptomatic of the current crisis in the NHS.
Scottish Conservative Shadow Health Secretary Dr Sandesh Gulhane called them a “devastating” indictment of Humza Yousaf’s stewardship of the health service.
"It’s disgraceful that fewer than 70 per cent of patients are being seen within four hours,” he said.
Liberal Democrat leader Alex Cole-Hamilton warned the waiting times are “not safe”, and would “prove deadly”.
“If people hold off asking for help, small problems will become much worse. The ripple effects of this emergency care crisis will roll on for years to come,” he said.
He added: “This is the worst it’s been in over a decade. The Health Secretary must commit to a full independent inquiry into the unnecessary deaths arising of this emergency care crisis. There needs to be accountability from the top.”
Scottish Labour health spokesperson Jackie Baillie said: “A&E services are in crisis, with the situation rapidly deteriorating with every passing week.
“Hard-pressed frontline staff have been sounding the alarm for months, but the Health Secretary has spectacularly failed to take action.”
Mr Yousaf apologised on Tuesday for any suffering caused by longer A&E waits.
The health secretary has also pledged £10 million in funding to help “ease pressures” on A&E, including placing physiotherapists and occupational therapists in emergency departments to reduce unnecessary admissions.
A Scottish Government spokesperson said: “A&E units across Britain have been hit by the direct and indirect impacts of Covid – and every day our incredible A&E staff are treating thousands of people, ensuring those most in need get seen quickest.
“Scotland’s core A&E departments continue to outperform those in the rest of the UK, and have done so for more than six years. However, we recognise some people aren’t getting the service they, or we, would expect and we apologise to anyone who has suffered as a result.”