First, the money rushed into hedge funds. Now, some fear, it could rush out.

Even as Washington reached a tentative agreement on Sunday over what may become the largest financial bailout in American history, new worries were building inside the nearly $2 trillion world of hedge funds. After years of explosive growth, losses are mounting  and so are concerns that some investors will head for the exits.

No one expects a wholesale flight from hedge funds. But even a modest outflow could reverberate through the financial markets. To pay back investors, some funds may be forced to dump investments at a time when the markets are already shaky.

The big worry is that a spate of hurried sales could unleash a vicious circle within the hedge fund industry, with the sales leading to more losses, and those losses leading to more withdrawals, and so on. A big test will come on Tuesday, when many funds are scheduled to accept withdrawal requests for the end of the year.

“Everybody’s watching for redemptions,” said James McKee, director of hedge fund research at Callan Associates, a consulting firm in San Francisco. “And there could be a cascading effect, where redemptions cause other redemptions.”