Doctors are planning to use special software to score coronavirus patients and help decide who gets an intensive-care bed if there aren't enough.
The New Zealand-developed "1000minds" tool is already used to guide clinicians dealing with a surge in cases in Italy, and will be rolled out across intensive-care units here within a week.
Dr Andrew Stapleton of the Australian and New Zealand Intensive Care Society stressed the software would help guide a group of doctors, who would ultimately make medical decisions themselves.
It would be used only if there aren't enough intensive-care beds for the number of Covid-19 patients needing one.
"It is a diagnostic aid. It is absolutely not a computer making the decision between life and death," he told the Herald. "You have one bed and four patients - who are you going to give the bed to? The tool will aid that decision, it will not make that decision."
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It would be "extraordinary" if New Zealand didn't face a situation where there aren't enough intensive-care beds needed for Covid-19 patients, he said.
"We have many advantages - we have a good head start, we are far away so it's been slow to get here, the Government has listened to the scientific advice it has had, and some of it is from us, and we are very pleased with their response."
The Intensive Care Society chaired a working group to consider how to triage Covid-19 patients, with members including an ethicist, Māori health leader, a paediatrician and infectious disease specialist.
Their work includes use of the "1000minds" software, which arose from research at the University of Otago and is already used in New Zealand to decide the most needy patients for some elective procedures. Other countries are considering using the software to help prioritise coronavirus patients.
The software works by first presenting patient vignettes to clinicians. In deciding who should be treated next a set of criteria is worked out, and then weighted according to importance. This information is used by the software to create a score for real-life patients.
That score would then help a group of intensive care doctors decide who should get a bed, when there aren't enough to go around (it would only be used for Covid-19 patients). Stapleton declined to go into detail about what factors helped score patients, but said some were obvious.
"Extremes of age, extremes of weight, extremes of chronic disease - clearly they are all factored into that."
The Covid-19 triage work is currently with the Ministry of Health for review, Stapleton said, and ideally would be ready for use within about a week.
Intensive-care doctors in some parts of Italy have faced the horror of deciding who to treat and who to let die as the health system is overrun. Stapleton said that, in New Zealand, if there wasn't an ICU bed for somebody it wouldn't necessarily be a death sentence.
"There are lots of work-arounds happening in hospitals all over New Zealand right now ... there will be access to hospital care and advanced hospital care, even if there isn't access to intensive care."
Putting someone on life support wouldn't guarantee their survival, Stapleton said, and must be carefully considered, given what a gruelling experience it is for patients.
"When you are critically ill you lose 7 per cent of your muscle mass for every day that you are on a ventilator - it becomes clear why, if you are 85 and weigh 45 kilos, we are not keen to put those people on ventilators, irrespective of Covid.
"It is not a decision we take lightly at the best of times, and it's slightly unfortunate the way it is being portrayed - 'Only ventilators will save you and if there aren't enough you are all going to die'. I think that's an unsophisticated way of looking at it."
Figures put before Cabinet ministers show New Zealand could treble its current number of ICU or ventilated beds – which stood at fewer than 180. Hospitals are racing to triple the number of staff trained to use ICU equipment like ventilators.
Health workers have pleaded with New Zealanders to take the new restrictions seriously, including Dr Paul Young, a doctor at the intensive care unit at Wellington Regional Hospital, who wrote on Twitter: "I have never felt as scared as I do now ... Hospitals being completely overwhelmed means that people die of heart attacks, strokes, accidents, etc. They die of everything because the kind of healthcare we take for granted will not be available if our hospitals are full."
Six patients with coronavirus are currently in hospital. All are stable and none need ICU treatment. Stapleton said New Zealand's ICU beds run at about 80 to 90 per cent capacity all year, without any Covid-19 patients.
"Please stay at home, please don't go out. Most of us are going to get Covid and be fine ... but we mustn't all get it at once, because the few resources we've got will be overwhelmed. And then people who could have been saved, won't be saved. I think the Prime Minister specifically said - it could cost tens of thousands of lives in that circumstance. And that's exactly right."