The country’s largest operator of free-standing emergency rooms — urgent medical care providers that are not physically connected to any hospital — has been accused of deceiving their patients into paying fees of several thousand dollars.

Texas-based Adeptus Health, through its subsidiaries and partnerships, operates at least 90 free-standing ERs in Texas, Colorado, Arizona, and Ohio.

These emergency care operations are different than the increasingly popular “urgent care” centers that many Americans are familiar with.

Urgent care centers are usually not open 24 hours a day, and they are generally intended to treat patients who need to see a doctor quickly but can’t get in to see their primary care physician.

Free-standing emergency rooms are just what the name implies. Many are open at all hours, ever day, and they are staffed with nurses and doctors who can handle many of the same medical problems you’d go to a hospital ER for.

However, a new lawsuit contends that Adeptus is preying on consumer confusion about these two different types of care centers, with the goal of prying thousands of dollars in “Facilities Fees” from patients.

According to the complaint [PDF] filed last week in a federal court in Texas, Adeptus markets its emergency room locations for non-emergency medical care, but fail to disclose to patients that they will be hit with the same substantial Facilities Fees that you might see by going to an actual hospital emergency room. The complaint claims that these fees can be in excess of $6,000.

The named plaintiff in the lawsuit is a Colorado doctor who visited an Adeptus emergency room in Colorado Springs — operated under the company’s UCHealth banner — after experiencing hip pain resulting from a fall while shoveling snow.

He says he was not notified of any Facilities Fee before receiving treatment, which included a brief visit and physical exam with a doctor, followed by an X-ray. It wasn’t until months later that he received a bill from UCHealth that included a $1,200 fee — accounting for around 60% of the total invoice.

The plaintiff seeks class-action status for his suit, with the goal of representing anyone in Texas or Colorado who has charged a Facility Fee by an Adeptus-run emergency room in the last four years.

It accuses the company of fraud in violation of Colorado state law, violations of the Texas Deceptive Trade Practices Act, and unjust enrichment.

Britt Berrett, head of the Healthcare Management program at University of Texas at Dallas, tells the Dallas Morning News he’s not surprised that operators of these free-standing emergency rooms now find themselves involved in lawsuits.

“It’s a reflection of how chaotic this portion of the industry is right now,” Berrett tells the Morning News. “It’s the billing and economics that are often suspect.”

When reached for comment by Consumerist, a representative for Adeptus said the company does not comment on pending litigation.

Emergency rooms and services have been a growing problem for Americans who find themselves stuck with surprise medical bills.

An increasing number of hospitals are staffing their emergency rooms with freelance physicians and specialists who may not necessarily accept the same insurance as the hospital itself. So even if a patient knows that their local hospital is in their insurance company’s network, they may still end up with a bill if the doctor they see at the ER it out-of-network.

Similarly, we heard from several patients around the country who were slammed with expensive ambulance bills because the hospital outsourced this service or because municipal ambulance services were called. In some cases, the patient faced hundreds of dollars in bills even though they never went anywhere in the ambulance.

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