More than 400 nurse practitioners, physician assistants and other clinicians in northern Minnesota and Wisconsin voted to unionize in an effort to gain leverage over how they practice medicine at their Essentia Health clinics and hospitals.

The Minnesota Nurses Association announced Monday night that the group voted overwhelmingly to join its union. Essentia countered with plans to appeal a federal labor ruling and possibly undercut the entire organizing movement.

"We will and often do have to sacrifice ourselves and our families to care for those that have placed their lives in our hands," said nurse practitioner Eric Griffith, who accused his health system of preying on providers' compassion by forcing them to care for more patients with less time and resources. "It is time to tell Essentia that enough is enough."

The vote follows similar moves over the past year by primary care doctors at Allina Health clinics and staff doctors at Allina's Mercy Hospital campuses in Coon Rapids and Fridley, who are represented by New York-based Doctors Council. But the Essentia vote is unique, nationally, in that it weaves together advanced practice practitioners from International Falls, Minn., to Spooner, Wis., who work in primary care, specialty clinics and hospitals.

Essentia is appealing a decision by the National Labor Relations Board that allowed the vote because it believes this group is too varied to be represented collectively.

"It's a wide variety of settings and it's just different needs for different patients across all those settings and specialties," said Tonya Loken, Essentia's community relations director.

A contract trying to represent all of these providers could end up being too rigid when it comes to scheduling flexibility, she said, which in turn could restrict hours in some facilities and reduce options for patients.

"Anything is possible," she said, "which is the concern."

Unionization in health care has increased following the COVID-19 pandemic, which subjected providers to on-the-job infection risks, demanding hours and other pressures.

The movement also comes at a time of lean operating margins for health care providers. Essentia reported almost $2.8 billion in operating revenue in the 12 months ending July 2023, but a razor-thin operating margin of $100,000 after expenses.