The move brings the total number of lockouts to 89, including three workers in Bendigo who were shut out of the company’s three sites in the city after staff across the state walked off the job on Monday.

In response, the union has called on all workers to continue the strike action until Tuesday.

One of the locked out Bendigo workers, Deanne Lynch, said staff were “optimistic” about achieving a resolution to the impasse but were “not going to back down”.

“We’re all just banding together,” she said.

“We’re supporting each other, we’re regularly meeting, we’re completely united and we’re going to give it a good fight.”

A Dorevitch spokeswoman said the company was experiencing “minimal disruption to services” as a result of the strike and there had been “no impact to the services we provide public and private hospitals”.

“A number of contingencies have been implemented to limit the impact to patients and GPs,” she said.

“Our laboratories are continuing to process tests and work with GPs to deliver results as per usual.”