The California private equity firm that owns Hahnemann University Hospital and St. Christopher’s Hospital for Children has consolidated leadership of the Philadelphia facilities under one chief executive.

American Academic Health System LLC, which a year ago bought the hospitals for $170 million from Tenet Healthcare Corp., said this week in a memo to staff that Suzanne Richards, an executive with experience running hospitals in Southern California, took over on Monday as chief executive for both facilities.

The previous CEOs of the hospitals, Anthony Rajkumar at Hahnemann, on an interim basis, and George Rizzuto, who was appointed at St. Christopher’s last June, were not mentioned in the memo.

Officials at Hahnemann, St. Christopher’s, and American Academic did not respond to requests for comment.

Paladin Healthcare LLC, an investment firm in El Segundo, Calif., created American Academic to own its Philadelphia facilities. Paladin also owns four hospitals in Southern California and manages Howard University Hospital in Washington.

Since the acquisition, American Academic has made a series of management changes as it attempts to generate a financial turnaround at the money-losing Philadelphia operations.

St. Christopher’s in August laid off 45 people in its physician practices.