The Federal Reserve Board said Wednesday that it would provide up to $37.8 billion to the embattled insurer the American International Group to help it deal with a rapidly dwindling supply of cash.

The additional assistance is on top of $85 billion in a bridge loan that the Federal Reserve extended to A.I.G. in September, but it will take a different form. A spokesman for A.I.G., Nicholas Ashooh, said the new assistance was intended to keep the company from having to draw down the Fed loan so quickly.

The Fed threw A.I.G. the $85 billion lifeline shortly after the collapse of Lehman Brothers, when the financial markets were reeling and there were doubts the system could weather the demise of another big financial services company. At the time, the Fed’s loan was the most radical intervention ever by the central bank in a company’s affairs.

Even as A.I.G. now works through a major overhaul, the rest of the insurance industry is still struggling with the continuing turmoil in the financial markets. Shares of MetLife, the nation’s largest life insurer, fell 27 percent on Wednesday to close at $27 a share after the company said its third-quarter earnings would be down significantly from a year ago and that it had to raise new capital.