The Memorial Hermann Health System will scale back trauma care at its southwest Houston hospital, three years after its upgrade to treat the most complex cases was trumpeted as a linchpin of an emerging response to the area’s shortage of high-level, around-the-clock emergency departments outside the city’s center.

Leaders at the not-for-profit system said Thursday the decision, which brought statements of concern from others in the trauma care business, was made to accommodate a planned change in focus in the hospital’s service area to community health care. They cited the high rates of chronic disease and uninsured and underinsured individuals in the area.

“We want to redirect resources to keep people out of the hospital,” said Dr. Jamie McCarthy, the Memorial Hermann system’s chief physician executive. “Also, there is now greater trauma capacity across our region, reducing the pressure on the Level I trauma centers in the Texas Medical Center.”

McCarthy added that complex trauma accounts for less than 1 percent of the hospital’s volume from the area. He said he is confident that the trauma-care system in the medical center, just 10 minutes away, will be able to absorb complex cases currently being taken to Memorial Hermann Southwest.

But Dr. David Persse, director of Houston Emergency Medical Services, called Memorial Hermann’s plan “absolutely” a blow. He said the system’s southwest hospital is a frequent destination EMS brings patients and described it as “very busy.”

“We’ll go back to the old days, where we bring most of our most serious trauma cases to the medical center and threaten to overburden them,” said Persse. “So people need to wear their seat belts, don’t drink and drive and stay out of gunfights.”

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The switch will make Memorial Hermann-Southwest a Level IV trauma center, the lowest trauma-care designation and down from its current Level II operating status. Level II centers are considered key components of trauma care because they are also able to treat severe, life-threatening cases and can compensate for a shortage of Level 1 centers.

Ben Taub and Memorial Hermann in the medical center provide Houston’s only two Level I adult trauma centers, though there is a third at the University of Texas Medical Branch at Galveston. The American College of Surgeons recommends an area the size of Houston have at least six Level I trauma centers.

The Houston area will still have three Level II trauma centers, all in suburbs in the south and north — HCA’s Clear Lake Regional Medical Center, Memorial Hermann The Woodlands and Conroe Regional Medical Center. There will be none in the area’s east and west.

In the early 2000s Houston emergency doctors citing similar sobering local statistics, urged the state to create another Level 1 trauma center, to no avail. Among their statistics: 25 percent of patients with severe injuries who required a transfer to a major trauma center died on days when the emergency departments of Ben Taub and Memorial Hermann-Texas Medical Center both diverted ambulances to other facilities.

The plan to scale back Memorial Hermann-Southwest’s trauma care, communicated to employees this week after a period of consideration, will begin immediately and continue until the end of the year, said McCarthy. The hospital is technically designated a Level III trauma center, even though it operates as a Level II. It has stopped operating as a Level II and will transition to a Level IV over the coming months.

Darrell Pile, CEO of SouthEast Texas Regional Advisory Council, a nonprofit that helps coordinate trauma care in the region, said he wished Memorial Hermann-Southwest had decided to stay a Level III center.

“It is concerning that we will no longer have a designated Level II or even Level III trauma center in that area,” said Pile. “It leaves a very large area, including Fort Bend, Wharton and Matagorda, with only one small nearby Level III trauma center.”

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The change must ultimately be approved the state. McCarthy said he envisions no problem with such approval, which requires a state visit after the change is complete.

McCarthy acknowledged that high-level trauma centers are “expensive: and that shifting resources is “a better use of money for a non-profit that doesn’t have unlimited resources.” It upgraded trauma capabilities in 2016, then-President Chuck Stokes said, because “no one else had stepped up to meet the need.”

McCarthy said Thursday the three Level II trauma centers that will remain, all of which came online about the same time, have performed above expectations.

Under the new plan, Memorial Hermann Southwest will emphasize the use of “navigators” to partner with uninsured and underinsured patients in the ER to connect them with appropriate medical homes and needed resources. It recently opened a Community Resource Center, a one-stop shop staffed by system social workers and other local organizations, including two federally qualified health centers and the Houston Food Bank.

Other aspects of the plan include a federal program giving patients in need access to discounted prescription drugs; a pilot program with Meals on Wheels to deliver to patients who face food insecurity or who are unable to cook or shop for themselves; on-site support groups to sustain lifestyle changes; the availability of medical screening exams to ER patients regardless of their insurance status.

The switch nevertheless prompted concern not just from Persse but from the Harris Health System, which operates Ben Taub.

“When closures like this happen in vulnerable communities, the ripple effects extend well beyond this singular location to other area hospitals,” King Hillier, Harris Health’s vice president of public policy and government relations, said in a statement. “Harris Health is concerned this action can spill over into our already busy emergency departments and other area hospitals. Our primary concern is sustaining the safe, prompt access to care that all trauma and emergency patients in the community need.”

Memorial Hermann officials defended the plan.

“While we cannot speak for Ben Taub’s capacity, its ability to care for its patients or how it uses its own resources, we have and will continue to have the resources, capacity and expertise available at Memorial Hermann-Texas Medical Center to provide life-saving care to patients who come through our doors, including those with the highest levels of need,” the system said in a statement.