A symbolic circle of support will be formed by those taking part in the lunchtime protest.
"The quiet format is a demonstration of the heartfelt and reasoned messages from clinicians and ordinary people who share a concern for the health and well-being of our community," New Zealand Nurses Organisation (NZNO) representatives Glenda Alexander and Lorraine Lobb said.
The 12.15pm protest is being organised by NZNO and organisers of the Keep Neurosurgery in Dunedin Facebook page, Associate Prof Samuel Mann and Southern District Health Board member Richard Thomson.
Ms Alexander said she hoped as many people as possible would take part in the protest to show the Ministry of Health its centralised health strategy was not supported and did not meet regional needs and access, put patients at risk, was not productive or economic and made "no sense at all".
The Facebook page has more than 5400 members. Prof Mann said he had expected about 300 people to join the site.
The site had been inundated with thousands of messages of encouragement, exhortations to keep the service in Dunedin, and personal examples of how neurosurgery in Dunedin had saved lives.
Site members were more than 80% female, with 69% aged 35 or over.
Prof Mann, a professor of information technology at Otago Polytechnic, said he wanted to increase the membership among Otago's student population, particularly medical students.
The website complemented the Otago Daily Times' more "in-depth" coverage.
Prof Mann said he and Mr Thomson had received an assurance people's views on the Facebook page and other forums would be heeded by the panel set up to review neurosurgery in the South Island.
Panel member David Russell told the Otago Daily Times he was uncomfortable commenting about his role on the panel, which is yet to meet or release its terms of reference.
However, he said he was on the panel to represent the interests of the people.
