Dr. Mark I. Langdorf, director of emergency at UC Irvine Medical Center in Orange, says the shortage means staff members must spend hours on the phone trying to find a specialist for a patient or arrange a transfer to a larger hospital, the Los Angeles Times reports Friday.

Except for county and university hospitals, California law prevents hospitals from directly employing physicians. Instead, they must contract with individual specialists or groups that do their own billing.

The Times says the increase in the number of patients without medical insurance is the most obvious reason for the declining number of specialists willing to serve emergency rooms.

Jim Lott of the Hospital Association of Southern California told the Times additional reasons as patients who are often drunk or on drugs, a higher risk of being sued by patients, and insurance companies that severely limit doctors' payments.