Health officials believe some patients will end up dying because of last week's industrial action by nurses, citing several "critical incidents" that occurred because of delays in treatment.
Royal Perth Hospital executive director Frank Daly said there was indisputable evidence that overcrowding and delays in hospital emergency departments caused deaths, even if they did not occur immediately.
"I predict there are people who will die this week because of delays in their care last week," Professor Daly said.
"At RPH alone we had 78 beds closed at one time and all these elderly and vulnerable patients on trolleys for 30 or 40 hours, creating circumstances that were intolerable.
"There were a couple of critical incidents where a lady waited too long to get a bed, became delirious and fell out of bed and hit her head.
"And another patient whose care was delayed and they deteriorated and ended up on a ventilator."
Nurses voted at a mass meeting on Monday to accept an in-principle pay offer from Premier Colin Barnett for a 14 per cent increase over three years, an offer matched by Labor.
It came after a week of work bans that forced the closure of one in five beds in most hospital wards and on the eve of a threatened 24-hour strike.
The Australian Nursing Federation ran an advertisement in _The West Australian _yesterday, thanking the public for "thousands of messages of support" in the dispute.
"Contrary to some reports, no lives were ever put at risk and the care of our patients was never compromised," it said.
Director-general of health Kim Snowball said he did not want to criticise individual nurses but it was important the public understood the inevitable risk to patients. He had warned Mr Barnett and his department last Sunday that hospitals could not cope with any escalation in industrial action, and he had even considered closing some hospitals to consolidate bed numbers.
"I had St John Ambulance on the phone saying they simply had no capacity to respond to call-outs because so much of their fleet was ramped outside hospitals, and at one stage there was one ambulance for the whole northern suburbs," he said.
Mr Snowball said 170 cases of elective surgery were cancelled at Royal Perth, Sir Charles Gairdner and Fremantle hospitals, which had started cancelling another 125, including category one "urgent" patients, under the threat of a strike.
He said it would take weeks, if not months, to clear the backlog and get hospitals back to normal.