Queen’s Medical Center is putting the final touches on its $100 million West Oahu hospital opening on May 20.

Queen’s unveiled the 80-bed hospital to media Tuesday after completing testing of its information technology systems and medical scenarios in anticipation of opening day.

The facility, then known as Hawaii Medical Center-West, closed in December 2011 as part of a lengthy and contentious bankruptcy. That left West Oahu residents with Pali Momi Medical Center in Aiea as the closest acute-care hospital and put an immediate strain on the island’s emergency medical services. Ambulances were forced to drive farther, overloading the island’s remaining emergency rooms.

As part of the bankruptcy, the Ewa hospital was returned to St. Francis Healthcare System of Hawaii. Queen’s acquired the facility in December 2012, and said at the time that it planned to invest more than $70 million in the land and hospital acquisition.

Queen’s has more than doubled emergency room capacity to 23 beds from 10 and expanded clinical areas. It has 450 workers on staff, about half from the surrounding community.

Services will include emergency room, inpatient and outpatient surgery, imaging, cardiology and specialty clinics. Queen’s said it will increase the number of beds to more than 130 as volume increases.