Maine Medical Center’s new $40 million operating wing gives the state’s largest hospital some 21st century surgery facilities, officials said, supplementing the hospital’s 35-year-old existing operating rooms.

The 41,361-square-foot expansion adds two stories to a section of the hospital, a gleaming glassed-in space that contrasts with the original building’s 1870s-era architecture. Surgeries will begin Oct. 19, and the expansion is being shown off to the public this week.

Construction began in February 2014, with the exterior completed early this year.

The hospital’s five new operating rooms will focus on surgeries needed for the brain and spine, although the space is flexible so the rooms could be used for any surgeries. Typical surgeries would be to remove brain tumors, treat aneurysms, or do spine surgeries and neck fusions.

Dr. Brad Cushing, chairman of Maine Med’s surgery department, said that as technology has improved – and surgeries have become less invasive – more specialists need to be in the operating room. Also, the medical equipment required for the surgeries has expanded, causing a space crunch for some surgeries in the older rooms.

The new operating rooms are 600 square feet, about 50 percent larger than the hospital’s existing 24 surgery rooms in the emergency wing.

The new expansion also includes a waiting room and 20 surgery prep and recovery rooms.

Cushing said the number of surgeries done by Maine Med is steadily increasing – it performs about 30,000 every year. Cushing said he sees two primary reasons for the change – Maine Med is getting more referrals from other parts of the state, and more patients are choosing surgery because many procedures are much less invasive than in years past.

“Why would you take medication for five years if you could have outpatient surgery?” Cushing said. “The complexity of these surgeries has gone up enormously.”

Marty Riehle, vice president of patient care services, said one example is gallbladder removal surgery. Thirty years ago, the incision would have been large, patients would spend a week or more in the hospital and recovery time was six weeks or longer. Now it’s outpatient surgery and patients usually can be back to work within two weeks.

“If you’re out of work any longer than that, you’re malingering,” Riehle said.

Cushing said that with the new operating rooms, patients who were waiting for scheduled surgeries are now less likely to have their surgeries delayed if someone is brought in for an emergency procedure.

Emergency room beds are typically 93 percent full, but the department operates more efficiently and better serves patients if average utilization is lower, Cushing said.

“Patients were getting their surgeries delayed far too often, and they were sometimes getting delayed for a very long time,” he said.

In 2016, one of the older operating rooms will be converted into a “cardiac hybrid operating room” for advanced surgeries. Cushing said that renovation will allow the hospital to potentially increase the number of minimally invasive cardiac surgeries.

About 3 percent of cardiac surgeries are minimally invasive, and Cushing said he expects that percentage will grow over the next 10 years.

“This will improve access to care for patients and improve the patient experience,” Cushing said.