In the past five years, more and more businesses have been investing in their own in-house medical centers, hoping to save on employer-provided health insurance by keeping their workers out of emergency rooms.

One such company is Maryland Live Casino, which has made free medical services available to employees and their families since the Anne Arundel County gaming hall opened in 2012.

“From the very beginning, before they even knew it was going to be financially successful, they bought off on [the in-house clinic] before they even had a strong revenue stream. They said. ‘This is the right thing to do for our employees,’ ” said Randy Hart, a benefits consultant at Cleveland-based CBIZ who advised Maryland Live on its benefits package.

With a staff of just two people — an office administrator and a nurse-practitioner — the clinic serves several hundred patients each month, and the company says employees rarely spend more than five minutes in the waiting room.

The company recognizes that many of their employees don’t have access to primary-care networks and instead rely on costly emergency room visits for the smallest of check-ups. A nurse practitioner can’t take on the same duties as a doctor, so the clinic focuses on preventive care and basic treatment. Clinic staff can’t set broken bones, they don’t draw blood and they don’t conduct any diagnostic testing. But they can treat such issues as flu symptoms, upper-respiratory problems, migraines, high blood pressure, dizziness, back pain, and eye and ear infections — which if treated in the emergency room could cost 10 times as much.