NovaMed Inc., a Chicago-based operator of ambulatory surgery centers, said Friday that it has agreed to be acquired for $214 million by a Florida company called Surgery Center Holdings Inc.

Surgery Center, based in Tampa, is an affiliate of a Miami-based private equity firm, HIG Capital. The price includes assumption of $105 million in debt.

Under the terms of the merger agreement, a release said, NovaMed stockholders would receive $13.25 per share in cash, a premium of 17 percent over the company’s 90-day average closing price.

The company said holders of 10.5 percent of NovaMed stock have approved the deal, but the merger will require additional consent by a majority of the company’s shareholders.

NovaMed, which is run by Chief Executive Thomas Hall, partners with physicians to operate, develop and acquire ambulatory surgery centers. It holds a majority stake in 37 surgery centers in 19 states.

As of last April, the date of the company’s most recent proxy statement, the largest stake in the company, 13.7 percent, was controlled by an investment firm called Wellington Management Co. and another 6 percent was owned by Wellington Trust Co. The biggest individual holders were River Forest ophthalmologists Kent Kirk and Scott Kirk who together owned 10.8 percent of the stock. Hall, the CEO, owned 4.5 percent.